Towards molecularly imprinted polymers selective to peptides and
proteins.The epitope approach
Alexandre Rachkov a,Norihiko Minoura b Y*
a Institute of Molecular Biology and Genetics,National Academy of Sciences of Ukraine,Kiev252143,Ukraine
b Department of Organi
c Materials,National Institute of Materials an
d Chemical Research,Higashi1-1,Tsukuba,Ibaraki305-8565,Japan
Received8February2000;received in revised form5September2000;accepted19September2000
Abstract
In this paper,we describe the epitope approach to molecular imprinting.The applicability of molecular imprinting,a method that allows the preparation of biomimetic compounds(artificial receptors and antibodies),is extended by this approach.Our approach makes it possible to obtain imprinted polymers selective to peptides and proteins whereas,to date, molecular imprinting has been used primarily for the preparation of polymers that selectively bind to relatively low molecular weight substances.The epitope approach is based on using(as a template)a short peptide that represents only part of a larger peptide or protein(as an epitope represents an antigen),which in turn can be recognized by the synthesized polymer.It is demonstrated that although other parts of peptides can influence the process of molecular recognition,the polymers imprinted with a short peptide efficiently recognize both the template and larger peptides(for example,oxytocin)that possess the same C-terminal part of the structure.?2001Elsevier Science B.V.All rights reserved.
Keywords:Molecular recognition;Imprinted polymer;Epitope approach;Oxytocin;Circular dichroism;Peptide conformation
1.Introduction
Molecular imprinting is a method for preparing polymers of predetermined selectivity for the separa-tion and analysis of a vast variety of biologically active or harmful substances[1^4].The technique involves the formation of complexes between a print molecule(template)and a functional monomer based on relatively weak,noncovalent interactions(hydro-gen bonding,ionic,hydrophobic,etc.).These com-plexes appear spontaneously in the liquid phase and are then￠xed sterically by polymerization with a high degree of cross-linking.After extracting the print molecules from the synthesized polymer,free recognition sites,which are able to recognize the template during subsequent rebinding procedures,re-main in the polymer matrix.Chemically and mechan-ically stable molecularly imprinted polymers(MIPs) able to recognize speci￠c substances may successfully serve as substitutes for antibodies,enzymes or other native biological structures in fundamental investiga-tions of molecular recognition and may have numer-ous other applications in biotechnology,medicine, environmental control,etc.
Usually,only relatively low molecular weight com-pounds(sugars,steroids,amino acid derivatives,cer-tain drugs and pesticides)are used as templates.To date,at least two e?ects have been reported to hinder
0167-4838/01/$^see front matter?2001Elsevier Science B.V.All rights reserved. PII:S0167-4838(00)00226-0
the synthesis of MIPs selective to macromolecules such as proteins:steric and thermodynamic.The steric e?ect is based on the notion that bulky protein templates cannot slip in and out of a polymer net-work[5].Therefore,attempts to synthesize protein selective MIPs have been mainly associated with the so-called surface imprinting procedure.Unfortu-nately,this procedure,using metal(Cu 2)chelating monomers,can be applied only to proteins contain-ing exposed histidine residues[6,7].However,the physical structure of macroporous MIPs provides another means of overcoming this problem.It is well known that the diameters of globular proteins having one polypeptide chain and proteins possessing a more complex structure(for example,hemoglobin) do not usually exceed5^10nm.Macroporous MIPs have been shown to possess a signi￠cant internal sur-face area(250^500m2g31)and a broad distribution of large pores(s50nm)[3],which ensures that not only solvents and low molecular weight substances, but also peptides and proteins have access to an es-sential fraction of the polymer mass.According to Wul?[1],the speci￠c microcavities formed by the imprinting process(about0.5^1.5nm in diameter) are located on the surfaces of the above-mentioned large pores.
Thermodynamic considerations[8]indicate that the use of non-rigid templates,such as polypeptides
or proteins,yield less well-de￠ned recognition sites in MIPs.Indeed,attempts to involve the protein itself in the polymerization process by entrapping it in polysiloxane or in polyacrylamide polymers[9^12] have been characterized by low speci￠city and unsat-isfactory reproducibility.On the other hand,Mos-bach et al.[13^15]have demonstrated the e¤cient recognition of short oligopeptides(3^5amino acid residues)by MIPs imprinted with these oligopepti-des.
These considerations suggest a general method for the preparation of MIPs speci￠c to polypeptides and proteins:if a short peptide representing only a small exposed fragment of a protein structure is used as a template,then the resultant macroporous MIP rec-ognizing the imprinted peptide will also be able to recognize the whole protein molecule(Fig.1).We have termed this method the`epitope approach', from the fact that a similar means is employed by nature;in recognizing an antigen,an antibody inter-acts with only a small part of it,the epitope(the antigenic site of macromolecule).
2.Materials and methods
2.1.Materials
Methacrylic acid(MAA),ethylene glycol dimetha-crylate(EGDMA),and2,2P-azobis(2,4-dimethylva-leronitrile)were obtained from Wako(Osaka,Ja-pan).Tyr-Pro-Leu-Gly amide(YPLG),oxytocin, tocinoic acid,N-benzyloxycarbonyl-Pro-Leu-Gly amide(Z-PLG)and Gly-Leu-Tyr(GLY)were ob-tained from Sigma(St.Louis,MO,USA),mesotocin or(Ile8)-oxytocin from Bachem(Bubendorf,Switzer-land),and deamino oxytocin(DeAm-Oxy)from Bio-genesis(Poole,UK).[Asu1Y6]-oxytocin(Asu:L-K-aminosuberic acid),acetyl-L-tyrosine amide
(Ac-Fig.1.Schematic representation of the epitope approach.
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Tyr-NH2),acetyl-L-tyrosine ethyl ester(Ac-Tyr-OEt), leucine-enkephalin(YGGPL),L-casomorphin-5 (YPFPG)and Pro-Leu-Gly amide(PLG)were pur-chased from the Peptide Institute(Osaka,Japan). The acetonitrile used was of high performance liquid chromatography(HPLC)grade.Water was of Milli Q grade.
2.2.Polymerization
A bulk radical polymerization was carried out at 403C for16h using2,2P-azobis(2,4-dimethylvaleroni-trile)as the initiator.The polymers obtained were ground in a mortar and sieved to collect the20^45 W m fraction.The polymers were washed several times with acetonitrile and water containing5vol%acetic acid until the template could no longer be detected in the supernatant.Control(non-imprinted)polymers were synthesized under the same conditions,though in the absence of template.
2.3.Chromatographic evaluation
Chromatographic analyses were performed using a Tosoh8010HPLC system(Tosoh,Tokyo,Japan), which included a system controller and UV detector. Polymers were slurry-packed into100U4.6mm stainless steel columns.Samples(20W l,0.05mM) were analyzed at a￡ow rate of1.5or3ml min31 and monitored with the UV detector set at225or 275nm(using acetone or NaNO3as a void marker). The capacity factor(k P)was calculated as(t3t0)/t0, where t is the retention time of the solute and t0is the retention time of the void marker;the separation factor of a given non-template analyte was de￠ned as K=k P t/k P x,where k P t and k P x are the capacity factors of template and other compound,respectively[16].
2.4.Measurements of circular dichroism(CD)
CD spectra were obtained at room temperature (V253C)on a JASCO model J-720spectropolarim-eter using a cylindrical fused quartz cell with an op-tical path length of1.0cm.Solutions were prepared by weighing lyophilized substances;concentrations were about0.03mM.The solvent baseline was sub-tracted,and spectra were normalized in units of mo-lar ellipticity[a](deg cm2dmol31).3.Results and discussion
To explore the epitope approach,we chose the neurohypophyseal hormone,oxytocin.It plays the role of instigator of the birth process in mammals, enabling a pregnant female to start uterine contrac-tions during labor,to begin lactating,to bond with her newborn and,in general,to behave maternally. Oxytocin is believed to be responsible for initiating sexual receptivity in both males and females and for the bonding behavior between them(called`pair-bonding').Recently,it was reported that an imbal-ance in the production of oxytocin and opioid pep-tides,with a prevalence of opioid peptides,might underlie a condition of sexual impotence[17]. Oxytocin is a nonapeptide(Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Leu-Gly-NH2).The formation of a disul￠de bond between the Cys residues at positions1and6 results in a peptide consisting of a6-amino acid cy-clic portion and a3-amino acid C-terminus.Despite considerable progress in elucidating the structure of the oxytocin receptor,many aspects of the interac-tion between oxytocin and its receptor remain poorly understood[18].However,numerous enzymatic and immunological studies indicate a key importance of the3-amino acid acyclic tail in mediating intermolec-ular interactions.For example,the biological activity of oxytocin(but not vasopressin)is destroyed by chymotrypsin,which acts at the leucine^glycine amide bond.It has also been shown that the anti-genic site(epitope)of oxytocin is located at its C-terminus,since oxytocin antibodies cannot inhibit structurally similar hormones with a substitution at position8[19].It should be also noted that conver-sion of the C-terminal glycinamide group into a di-methylamide leads to a drastic reduction in both af-￠nity to the receptor and the hormone's intrinsic activity[20].
These features of oxytocin make it suitable for our investigation.It should be noted that epitopes on an antigen can usually be described as surface domains composed of three to six amino acid residues with a surface area buried in the process of antigen^anti-body interactions in the order of650^900A?2 [21,22].The area buried during the folding of a pro-tein or in an antigen^antibody interaction is directly related to the hydrophobic energy that helps com-pensate for the loss of conformational entropy.It is
A.Rachkov,N.Minoura/Biochimica et Biophysica Acta1544(2001)255^266257
known[23,24]that for an unfolded polypeptide chain,the total accessible surface area A t in an ex-tended conformation is directly proportional to its molecular weight:
A t 1X45M w
Therefore,this value for the tripeptide tail region of oxytocin is about450A?2,somewhat smaller than is usually needed.Moreover,PLG weakly absorbs UV light,making the control of polymer processing and further binding studies somewhat di¤cult.To over-come this problem,in our experiment we used as a template the tetrapeptide,YPLG.Its total accessible surface area is about650A?2,and the energy of hy-drophobic interactions in combination with the en-ergy of hydrogen bonding with functional monomers should be enough for e¤cient retention(recognition) of the peptides by an imprinted polymer.In addition, YPLG contains a Tyr residue,which can facilitate its UV and￡uorescence detection.It was also expected, that the bulkiness of the Tyr residue would further the formation of the recognition sites,which should recognize not only the template but also other pep-tides,including oxytocin,with a PLG C-terminal tri-peptide.
In view of the fact that a highly cross-linked mac-roporous copolymer of MAA as a functional mono-mer and EGDMA as a cross-linking agent has proved to be a very e¤cient matrix in the molecular recognition process by MIPs[14,25^27],we used these compounds in our investigation.
The usual quantity of relatively low molecular weight template required for MIP preparation is about1mmol;the optimal ratio of the template to functional monomer is reported to be from1:4to 1:18[14,26,27]or about four molecules of functional monomer per functional group of a template.To synthesize an anti-[Leu5]enkephalin MIP,only0.1 mmol of the template was used[14].We performed the polymerization with a smaller quantity(22W mol) of YPLG.YPLG possesses about10potential sites for hydrogen bonding.Therefore,we employed tem-plate to functional monomer ratios of1:10,1:20and 1:40.For all the synthesized polymers,6.6mmol EGDMA was used,and as a consequence,the func-tional monomer to cross-linking agent ratios ranged from1:30to1:7.5.Although the success of molec-ular imprinting is generally associated with the use of inert,nonpolar porogens such as chloroform or tol-uene[1,3,28],it is necessary to consider not only the polarity of the solvent but also the likelihood of it interacting with solute species,e.g.through hydrogen bonding[4,29].Therefore,for this study,acetonitrile was expected to be a more suitable porogen than,for example,chloroform.To ensure complete solubiliza-tion of the YPLG,we added a small quantity of water(about3vol%)to the￠nal polymerization mix-ture,which contained equal volumes of acetonitrile and monomers(MAA+EGDMA).
Elemental analysis of the resultant polymers was in good agreement with the composition described above.For example,for MIP1:10we calculate 60.43%C and7.10%H and found59.15%C and 6.91%H.The analysis of nitrogen content indicated almost complete removal of the template from the imprinted polymers.
Following polymerization and processing,the properties of the synthesized polymers were eval-uated by HPLC.At￠rst,this was done in the aque-ous-poor mobile phase,10vol%H2O/90vol%aceto-nitrile,modi￠ed by1mM acetic acid(without adjustment of pH).The results of the
chromato-
Fig.2.Chromatographic evaluation of the synthesized poly-mers.1:10,1:20and1:40indicate imprinted polymers having these ratios of template to functional monomer(YPLG/MAA). 0:10,0:20and0:40indicate the corresponding control(non-im-printed)polymers.The￡ow rate was3ml min31.The mobile phase consisted of1mM acetic acid/10vol%H2O/90vol%ace-tonitrile.UV detection occurred at275nm.
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graphic evaluation of the synthesized polymers (Fig.2)show successful imprinting with YPLG,since the MIPs retained YPLG much strongly than did the non-imprinted polymers.It is of primary importance that MIPs imprinted with the tetrapeptide (YPLG)also recognized oxytocin,a larger molecule bearing the same 3-amino acid C-terminus as that of the template used.In contrast to YPLG and oxytocin,
Ac-Tyr-NH 2essentially did not interact with any of the synthesized polymers.
In view of the facts that an increase in MAA con-tent led to a longer peptide retention and that non-speci￠c interactions with the non-imprinted polymer 0:40(template to MAA ratio)were higher than those of the two other control polymers,we conclude that the optimal ratio of the template to functional mono-mer lies between 1:10and 1:20.This observation suggests that of all the potential hydrogen bonding sites of YPLG,only some participate simultaneously in intermolecular interactions with MAA to form speci￠c recognition sites within MIPs.
Increasing the water content of the mobile phase,as expected,weakened the hydrogen bonding be-tween polymer and analyte.This resulted in a dra-matic change in the retention of the peptides by both the imprinted and non-imprinted polymers,whereas the level of interaction between both polymers and Ac-Tyr-NH 2remained the same (Fig.3).Ten percent water content in the aqueous-poor mobile phase was used in further experiments because it was a compro-mise between lower water concentrations,which as-sured a higher level of hydrogen bonding but limited solubility of the tested peptides,and higher water concentrations,which assured good peptide solubil-ity but restricted hydrogen bonding.
In the next stage of this investigation,we used a set of template-and oxytocin-related peptides to re-veal selectivity of the MIP (Fig.
4).
Fig.3.In￡uence of the water content of the mobile phase on the degree of interaction between the analytes and MIP 1:10(analyte/i)or the corresponding control polymer (analyte/n).The ￡ow rate was 3ml min 31.The mobile phase consisted of the indicated concentration of water in acetonitrile containing 1mM acetic acid (￠nal concentration).UV detection occurred at 275
nm.
Fig.4.Amino acid sequences of the tested peptides.Amino acid substitutions (compared with oxytocin)are designated in outline.[Asu 1Y 6]-oxytocin:cyclic form between Asu g -carboxyl group and Tyr K -amino group.Asu:L -K -aminosuberic acid.
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In the aqueous-poor mobile phase (10%H 2O/90%acetonitrile,modi￠ed by 1mM acetic acid,pH 5.0)the strong retention of the template YPLG,as well as that of PLG,oxytocin and mesotocin,by the MIP corresponds completely to the proposed epitope ap-proach of molecular imprinting.The same holds for the very weak retention of the tyrosine derivatives,Ac-Tyr-NH 2and Ac-Tyr-OEt (Fig.5).However,we did not expect the very weak retention of the pep-tides possessing the C-terminal PLG sequence (de-amino oxytocin and [Asu 1Y 6]-oxytocin)or the rather strong retention of peptides whose structures do not contain this sequence but do contain the N-ter-minal amino group (tocinoic acid,GLY,YPFPG and YGGPL).
To get an insight into the nature of the interac-tions,we investigated the in￡uence of the composi-tion of the mobile phase.It appears that a chromato-graphic mobile phase containing 2^5%acetic acid ensures the protonation of MAA residues within pol-ymers and thereby reduces the role of ionic interac-tions [14,30].Here,by using a much lower concen-tration of acetic acid (from 1to 10mM or from 0.006to 0.06vol%),we tried to approach the initial polymerization conditions and,consequently,the in-itial interactions (Fig.6).The lower the concentra-
tion of acetic acid,the better the recognition of the peptides by the MIP is.Along with increased reten-tion,we also observed a selectivity advantage of the template (YPLG)over the other tested peptides.The only exception was the retention of PLG,which was very similar to that of the template YPLG.The val-ues of the separation factor,K ,gradually increased,for example,from 1.48to 1.85for oxytocin and from 1.80to 2.87for tocinoic acid.
Changing the pH of the aqueous-poor mobile phase from pH 4to 7at all tested concentrations of acetic acid led to a progressive decrease of the retention of all analytes;however,the change in se-lectivity tended to be dependent on the analyte (Ta-ble 1).For example,PLG could not be separated from the template YPLG (with the only exception at pH 7and 2.5mM acetic acid:under these con-ditions,PLG was retained twice as strongly as the template).The highest value of the separation factor for tocinoic acid was achieved at pH 7and 5mM acetic acid;for oxytocin and the tripeptide GLY,the highest values were at pH 6and 2.5mM acetic acid.The di?erences in dependence on pH can be ex-plained,at least partially,by the di?erent p K a values of the N-terminal amino groups belonging to proline,tyrosine,glycine and cysteine.
Our investigations of the MIP^peptide interactions in an aqueous-rich mobile phase [31]also
demon-
Fig.5.Chromatography of peptides structurally related to the template or oxytocin by MIP 1:10and by the corresponding control polymer in the aqueous-poor mobile phase (10vol%H 2O/90vol%acetonitrile,modi￠ed by 1mM acetic acid,pH 5.0).The ￡ow rate was 1.5ml min 31.UV detection occurred at 225
nm.
Fig.6.In￡uence of the acetic acid content of the aqueous-poor mobile phase on the degree of interaction between the analytes and the MIP 1:10.The ￡ow rate was 1.5ml min 31.The mobile phase consisted of the indicated concentration of acetic acid in 10vol%H 2O/90vol%acetonitrile,pH 5.UV detection oc-curred at 225nm.
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260
strated the in￡uence of ionic strength and a clear dependence on the p K a values of the N-terminal ami-no acid.However,the pH values corresponding to the strongest retentions of the tested peptides were observed to be higher than 5.5.This di?erence can be associated with the fact that the pH value for a spe-ci￠c acid^base bu?er varies with the solvent compo-sition.For example,it has been shown that the pH values of a 0.01M acetate bu?er in water and in the mixture of 40%water and 60%acetonitrile di?er by almost two pH units [32].Our titration curves (Fig.7)show that in the mixture of 10%water and 90%acetonitrile,measured values of pH 4and 5corre-sponded not to an approximately half-ionized state of acetic acid but to an almost completely protonat-ed one.The same is probably true for the carboxy groups of MAA residues within the synthesized pol-ymers.It means that ionic interactions do not play a signi￠cant role in retention of the peptides by the MIP in the aqueous-poor mobile phase at pH 4,even at low concentrations (1^10mM)of acetic acid.Moreover,essential deprotonation of carboxy groups at pH 6and 7did not lead to the strengthen-ing of the peptide retention.
It should be noted that the increase of pH weak-ened retention of YPLG much more slowly than that of peptides not possessing the C-terminal PLG se-
quence.Oxytocin,whose structure includes both the speci￠c and nonspeci￠c fragments,is intermedi-ate in behavior.This could mean that the correct localization of the N-terminal amino group and the C-terminal PLG sequence (such as takes place in the structure of the template YPLG)is very important for peptide recognition by the MIP in the aqueous-poor mobile phase.
Unlike the case in the aqueous-poor mobile phase,
Table 1
Dependence of HPLC data for the MIP on concentration of acetic acid and pH a Acetic acid (mM)Analytes pH 4pH 5
pH 6
pH 7
k P i K
k P i K
k P i K
k P i K
2.5
YPLG 19.8714.637.35 1.86oxytocin 16.98 1.178.70 1.68 2.02 3.640.57 3.26PLG
18.35 1.0814.65 1.009.000.82 3.830.49tocinoic acid 12.13 1.64 5.84 2.51 1.81 4.060.40 4.65GLY 14.87 1.34
7.68 1.90
1.98 3.71
0.74 2.51
5
YPLG 12.139.73 4.56 1.80oxytocin 11.78 1.03 5.51 1.77 1.40 3.260.80 2.25PLG
12.05 1.019.51 1.02 5.020.91 2.380.76tocinoic acid 9.63 1.26 3.78 2.57 1.28 3.560.37 4.86GLY 10.72 1.13 4.76 2.04 1.33 3.430.63 2.86
10
YPLG 9.687.15 3.35 1.25oxytocin 9.25 1.05 4.82 1.48 1.19 2.820.60 2.08PLG
8.68 1.12 6.71 1.07 3.510.95 1.440.87tocinoic acid 8.15 1.19 3.98 1.80 1.25 2.680.29 4.31GLY
8.15
1.19 4.05
1.77 1.14
2.940.48
2.60
a
The mobile phase consisted of 10%H 2O/90%acetonitrile.Flow rate was 1.5ml min 31
.
Fig.7.Titration of 5mM acetic acid in di?erent mixtures of water and acetonitrile.
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the study of the MIP in the aqueous-rich mobile phase containing a citrate^phosphate bu?er [31]showed that oxytocin analogs,whose structures con-tain the C-terminal PLG sequence but not the N-terminal amino group,could also be speci￠cally rec-ognized by the MIP.Here,we demonstrate a similar result using an aqueous-rich mobile phase containing an acetate bu?er (Fig.8).It should be noted that under this condition,the peptides without the C-ter-minal PLG sequence (YGGPL,YPFPG,GLY and tocinoic acid)are retained by the MIP much more weakly than deamino oxytocin and [Asu 1Y 6]-oxytocin.Another di?erence from the results obtained in the aqueous-poor mobile phase is the striking retention of Ac-Tyr-OEt by the MIP;its k P i value increased by more than seven times,but it was retained by the control polymer at the close level.Consequently,this phenomenon can be easily explained by nonspe-ci￠c hydrophobic interactions with the polymer ma-trix.In fact,Z-PLG is an example of the strengthen-ing of the interaction of the speci￠c tripeptide segment in the aqueous-rich mobile phase by hydro-phobic substitution of the N-terminal amino group (compare retentions of Z-PLG and PLG).
To understand the reason for the di?erence in the recognition of deamino oxytocin and [Asu 1Y 6]-oxyto-cin by the MIP,depending on the composition of the
mobile phase,we should also take into consideration the ￡exibility of conformation of the oxytocin and its analogs.The conformation of oxytocin and its ana-logs has been the subject of intensive investigation using theoretical [33^35],X-ray di?raction [36,37],CD [38^40],Raman [41,42]and nuclear magnetic resonance studies [34,43^45].It was shown that the hormone can adopt conformations that are stabilized by intramolecular hydrogen bonds in the hexapeptide ring moiety and the tripeptide tail region [46].The crystal structure (deamino oxytocin)is characterized by a type II L turn within the ring stabilized by two trans -annular hydrogen bonds between Tyr 2and Asn 5and a weak hydrogen bond between the Cys 6CO and the Gly 9peptide NH,which holds the tri-peptide tail in the type I L turn [37].
The conformation of oxytocin in solution depends on the nature of the solvent.L turns stabilized by hydrogen bonds are maintained in organic solvents (dimethyl sulfoxide and tri￡uoroethanol)[34,44,46];acetonitrile can also promote the formation of or-dered structures [47].However,unlike these solvents,in an aqueous solution,oxytocin molecules are ex-tremely ￡exible and do not appear to participate in intramolecular hydrogen bonding [33,41,43,48].Moreover,it has been shown that there is consider-able intramolecular motion in the tail region of oxy-tocin with respect to the remainder of the molecule [45,49].
CD is a widely used spectroscopic technique val-uable for studying secondary structures of oxytocin and its analogs in solution.Such molecules are not su¤ciently large that their CD spectra can be inter-preted in terms of regular structures such as helical https://www.doczj.com/doc/9a17172355.html,ually,their CD spectra include a strong negative band near 200nm (due to an amide Z ^Z *transition)and a weak positive band near 220nm that corresponds to unordered polypeptide struc-tures [50].On the other hand,electronic transitions of peptide and disul￠de bonds,as well as aromatic chromophores of tyrosine,can produce a number of distinct bands in the CD curves.In spite of some di?erences in interpretation by di?erent authors,it is possible to make assignments for the extremely wide positive band in the 215^230nm range,the positive band at about 250nm,and the negative band near 280nm.The ￠rst band results from the superposition of two bands:the longer
wavelength
Fig.8.Chromatography of peptides structurally related to the template or oxytocin by MIP 1:10and by corresponding con-trol polymer in the aqueous-rich mobile phase (80vol%H 2O/20vol%acetonitrile,modi￠ed by 2mM acetic acid,pH 6.5).The ￡ow rate was 1.5ml min 31.UV detection occurred at 225nm.
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262
band can be assigned to the B1u transition of the tyrosine side chain and the band lying at a shorter wavelength to the n-Z*transition of the amide group (a negative band at230^240nm can also be assigned to this transition).Bands at about250and280nm are due to disul￠de group and tyrosine B2u transi-tion,respectively[38^40,51^53].
We surmised that in the aqueous-rich medium,the tested peptides would manifest CD spectra corre-sponding to less ordered structures than would be found in the aqueous-poor medium.This is especially true in the case of deamino oxytocin.The positive band due to B1u aromatic transition,which is clearly observed in a medium containing only10%water, completely disappeared when80%water was used (Fig.9).The di?erence in disul￠de bands indicates that the￡exibility of the disul￠de group increases when going from the aqueous-poor to the aqueous-rich medium.
CD spectra of[Asu1Y6]-oxytocin also di?ered mark-edly,depending on solvent composition(Fig.10).A moderate positive composite band was seen in the aqueous-rich medium;in the aqueous-poor medium this band clearly dissociates into a strong positive band at about232nm and a negative shoulder at about216nm.The change of sign of the band cor-responding to the amide n-Z*transition was ob-served by Fric et al.for[Cle8]-oxytocin and [Pen1,Cle8]-oxytocin[53].This change was supposed to be explained by the competition for the space over the20-membered ring moiety between the tyrosine side chain and some part of the C-terminal linear tripeptide.Taking into account the much weaker bands of[Asu1Y6]-oxytocin compared to that of [Cle8]-oxytocin and[Pen1,Cle8]-oxytocin,we can state that,in our case,we observed only partial re-striction of mobility of the tail region of[Asu1Y6]-oxy-tocin.
Thus,the CD measurements gave us some grounds for a proposed explanation of the di?erent chroma-tographic behaviors of the peptides,depending on the composition of the mobile phase.Probably,in an aqueous-poor medium the C-terminal linear tri-peptide of deamino oxytocin and[Asu1Y6]-oxytocin interacts quite strongly with the tocin ring;this could occur through the above-mentioned weak hydrogen bond between the Cys6CO and the Gly9peptide NH,a hydrogen bond between the Asn5amide car-bonyl and the Leu8NH[36],or some other interac-tion.In an aqueous-rich medium,the acyclic tail of the peptides tends to form conformations with ex-posed polar groups.In the structure of[Asu1Y6]-oxy-tocin,the presence of the aliphatic portion of amino-suberic acid instead of the disul￠de group favors the strengthening of hydrophobic interactions and there-fore decreases somewhat the￡exibility of the acyclic tail.Therefore,even in the aqueous-rich medium, [Asu1Y6]-oxytocin is retained more weakly by the MIP than is oxytocin or deamino oxytocin. Thus,we showed that it is not only the C-terminal linear tripeptide that can in￡uence the process of molecular recognition of oxytocin and oxytocin ana-logs by the MIP.Due to di?erent intermolecular
(for Fig.9.CD spectra of deamino
oxytocin.
Fig.10.CD spectra of[Asu1Y6]-oxytocin.
A.Rachkov,N.Minoura/Biochimica et Biophysica Acta1544(2001)255^266263
example,the case of nonspeci￠c peptides containing the N-terminal amino group in the aqueous-poor mobile phase)or intramolecular interactions(for ex-ample,the case of conformational￡exibility of de-amino oxytocin and[Asu1Y6]-oxytocin in the aqueous-rich mobile phase)caused by other parts of the mol-ecules,the￠nal retention pattern seems to be rather complicated.Nevertheless,it is possible to adjust the composition of the chromatographic mobile phase for selective recognition.Moreover,the presence of di?erent`excess'parts in the structures of the oxy-tocin and oxytocin analogs allows e¤cient separation of the di?erent peptides bearing the templated N-terminal sequence.
In conclusion,we have presented here a new ap-proach for the synthesis of MIPs selective to peptides or proteins and have demonstrated the successful application of the proposed https://www.doczj.com/doc/9a17172355.html,ing a small tetrapeptide as a template,we synthesized MIPs that were able to recognize oxytocin,a larger peptide pos-sessing the same structural fragment as that of the template.This approach for the development of MIPs selective to proteins is also attractive from an economic viewpoint;a small peptide is usually less expensive,and the quantity necessary for polymer preparation is more readily available than that of the corresponding protein.This investigation is one of the￠rst steps toward the creation of cost-e?ective, highly selective,e¤cient synthetic adsorbents and re-ceptors for a wide variety of proteins.
Acknowledgements
A.R.acknowledges a postdoctoral fellowship from NEDO(New Energy and Industrial Technology De-velopment Organization,Japan).
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to与for的用法和区别 一般情况下, to后面常接对象; for后面表示原因与目的为多。 Thank you for helping me. Thanks to all of you. to sb.表示对某人有直接影响比如，食物对某人好或者不好就用to; for表示从意义、价值等间接角度来说，例如对某人而言是重要的，就用for. for和to这两个介词，意义丰富，用法复杂。这里仅就它们主要用法进行比较。 1. 表示各种“目的” 1. What do you study English for? 你为什么要学英语？ 2. She went to france for holiday. 她到法国度假去了。 3. These books are written for pupils. 这些书是为学生些的。 4. hope for the best, prepare for the worst. 作最好的打算，作最坏的准备。 2．对于 1．She has a liking for painting. 她爱好绘画。 2．She had a natural gift for teaching. 她对教学有天赋/ 3．表示赞成同情，用for不用to. 1. Are you for the idea or against it? 你是支持还是反对这个想法？ 2. He expresses sympathy for the common people.. 他表现了对普通老百姓的同情。 3. I felt deeply sorry for my friend who was very ill. 4 for表示因为，由于（常有较活译法） 1 Thank you for coming. 谢谢你来。 2. France is famous for its wines. 法国因酒而出名。 5．当事人对某事的主观看法，对于（某人），对…来说（多和形容词连用）用介词to，不用for.. He said that money was not important to him. 他说钱对他并不重要。 To her it was rather unusual. 对她来说这是相当不寻常的。 They are cruel to animals. 他们对动物很残忍。 6．for和fit, good, bad, useful, suitable 等形容词连用，表示适宜，适合。 Some training will make them fit for the job. 经过一段训练，他们会胜任这项工作的。 Exercises are good for health. 锻炼有益于健康。 Smoking and drinking are bad for health. 抽烟喝酒对健康有害。 You are not suited for the kind of work you are doing. 7. for表示不定式逻辑上的主语，可以用在主语、表语、状语、定语中。 1．It would be best for you to write to him. 2．The simple thing is for him to resign at once. 3．There was nowhere else for me to go. 4．He opened a door and stood aside for her to pass.
古漢語通論（三） 單音詞，複音詞，同義詞 我們研究古代漢語的時候，需要了解單音詞和複音詞的關係，複音詞和同義詞的關係，因為這有助於我們更徹底地了解古代漢語。 我們隨便把一篇古文翻譯成為現代漢語，就會發現譯文比原文長了許多。這主要是因為古代漢語的詞彙以單音詞為主，而現代漢語的詞彙以複音詞（主要是雙音詞）為主。例如“蹇叔之子與師”（《左傳》僖公三十二年）這一個句子中，“子”字在現代一般總說成“兒子”，“與師”更非譯成兩個複音詞“參加軍隊”不可。 古代單音詞和現代複音詞的對比，主要有三種情況：第一種情況是換了完全不同的詞，例如“與”變成“參加”，“師”變成“軍隊”；第二種情況是加上詞尾詞頭，如“虎”變成“老虎”，“杯”變成“杯子”，“石”變成“石頭”；第三種情況是利用兩個同義詞作為詞素，構成一個複音詞，例如“兒”和“子”是同義詞，合起來成為複音詞“兒子”。 最值得注意的是第三種情況。有許多古代的單音詞，作為詞來看，可以認為已經死去了；但是作為詞素來看，它們還留存在現代漢語裏。舉例來說，古代漢語有單音詞“慮”字。《論語·衛靈公》：“人無遠慮，必有近憂”；《詩經·小雅·無雨》：“弗慮弗圖”。但是，在現代漢語裏，“慮”字只作為詞素留存在“顧慮”、“考慮”等雙音詞裏，或者只出現在“深謀遠慮”，“深思熟慮”等成語裏，而不能作為單詞自由運用了。 漢語大部分的雙音詞都是經過同義詞臨時組合的階段的。這就是說，在最初的時候，只是兩個同義詞的並列，還沒有凝結成為一個整體，一個單詞。這可以從兩方面證明：第一，最初某些同義詞的組合沒有固定的形式，幾個同義詞可以自由組合，甚至可以顛倒。例如“險”“阻”“隘”（注：“隘”單用時，是狹的意思，同“險”“阻”的區别較大。）是同義詞，在上古常常單用，又可以互相組合。《左傳》僖公二十二年，既有“隘而不列”，“阻而鼓之”，又有“不以阻隘也”，“阻隘可也”。後兩句“阻”和“隘”雖然連在一起，但顯然還是兩個詞。在《史記·孫子吳起列傳》中有：“馬陵道陝（狹），而旁多阻隘”，“阻”和“隘”組合得緊一些。又《史記·淮陰侯列傳》：“恐吾至阻險而還”，是“阻”和“險”相結合。同時我們還可以看到，《左傳》成公十三年有“險阻”（逾越險阻），《離騷》中有“險隘”（路幽昧以險隘）。這說明三個同義詞組合時，各自的獨立性還很強，沒有組成新的單一的詞，還是自由組合的情況。第二，古人對於這一類同義詞，常常加以區别。例如“婚姻”很早就
介词for用法归纳 用法1：(表目的)为了。如： They went out for a walk. 他们出去散步了。 What did you do that for? 你干吗这样做？ That’s what we’re here for. 这正是我们来的目的。 What’s she gone for this time? 她这次去干什么去了？ He was waiting for the bus. 他在等公共汽车。 【用法说明】在通常情况下，英语不用for doing sth 来表示目的。如： 他去那儿看他叔叔。 误：He went there for seeing his uncle. 正：He went there to see his uncle. 但是，若一个动名词已名词化，则可与for 连用表目的。如： He went there for swimming. 他去那儿游泳。(swimming 已名词化) 注意：若不是表目的，而是表原因、用途等，则其后可接动名词。(见下面的有关用法) 用法2：(表利益)为，为了。如： What can I do for you? 你想要我什么？ We study hard for our motherland. 我们为祖国努力学习。 Would you please carry this for me? 请你替我提这个东西好吗？ Do more exercise for the good of your health. 为了健康你要多运动。 【用法说明】(1) 有些后接双宾语的动词(如buy, choose, cook, fetch, find, get, order, prepare, sing, spare 等)，当双宾语易位时，通常用for 来引出间接宾语，表示间接宾语为受益者。如： She made her daughter a dress. / She made a dress for her daughter. 她为她女儿做了件连衣裙。 He cooked us some potatoes. / He cooked some potatoes for us. 他为我们煮了些土豆。 注意，类似下面这样的句子必须用for： He bought a new chair for the office. 他为办公室买了张新办公椅。 (2) 注意不要按汉语字面意思，在一些及物动词后误加介词for： 他们决定在电视上为他们的新产品打广告。 误：They decided to advertise for their new product on TV. 正：They decided to advertise their new product on TV. 注：advertise 可用作及物或不及物动词，但含义不同：advertise sth＝为卖出某物而打广告；advertise for sth＝为寻找某物而打广告。如：advertise for a job=登广告求职。由于受汉语“为”的影响，而此处误加了介词for。类似地，汉语中的“为人民服务”，说成英语是serve the people，而不是serve for the people，“为某人的死报仇”，说成英语是avenge sb’s death，而不是avenge for sb’s death，等等。用法3：(表用途)用于，用来。如： Knives are used for cutting things. 小刀是用来切东西的。 This knife is for cutting bread. 这把小刀是用于切面包的。 It’s a machine for slicing bread. 这是切面包的机器。 The doctor gave her some medicine for her cold. 医生给了她一些感冒药。 用法4：为得到，为拿到，为取得。如： He went home for his book. 他回家拿书。 He went to his friend for advice. 他去向朋友请教。 She often asked her parents for money. 她经常向父母要钱。
For的用法 1. 表示“当作、作为”。如: I like some bread and milk for breakfast. 我喜欢把面包和牛奶作为早餐。 What will we have for supper? 我们晚餐吃什么? 2. 表示理由或原因,意为“因为、由于”。如: Thank you for helping me with my English. 谢谢你帮我学习英语。 3. 表示动作的对象或接受者,意为“给……”、“对…… (而言)”。如: Let me pick it up for you. 让我为你捡起来。 Watching TV too much is bad for your health. 看电视太多有害于你的健康。 4. 表示时间、距离,意为“计、达”。如: I usually do the running for an hour in the morning. 我早晨通常跑步一小时。 We will stay there for two days. 我们将在那里逗留两天。 5. 表示去向、目的,意为“向、往、取、买”等。如: Let’s go for a walk. 我们出去散步吧。 I came here for my schoolbag.我来这儿取书包。 I paid twenty yuan for the dictionary. 我花了20元买这本词典。 6. 表示所属关系或用途,意为“为、适于……的”。如: It’s time for school. 到上学的时间了。 Here is a letter for you. 这儿有你的一封信。 7. 表示“支持、赞成”。如: Are you for this plan or against it? 你是支持还是反对这个计划? 8. 用于一些固定搭配中。如: Who are you waiting for? 你在等谁? For example, Mr Green is a kind teacher. 比如,格林先生是一位心地善良的老师。 尽管for 的用法较多，但记住常用的几个就可以了。 to的用法: 一：表示相对，针对 be strange (common, new, familiar, peculiar) to This injection will make you immune to infection. 二：表示对比，比较 1：以-ior结尾的形容词，后接介词to表示比较，如：superior ,inferior,prior,senior,junior 2: 一些本身就含有比较或比拟意思的形容词，如equal，similar，equivalent，analogous A is similar to B in many ways.
单音词、复音词和同义词 【教学大纲】古代汉语是以单音词为主，现代汉语是以双音词为主，故不可将古代汉语中的单音词误认为双音词中的一个词素。复音词中要注意偏义复词和单纯联绵词。要注意辨析古汉语中的同义词，可以从含义差别、使用范围、使用条件等方面辨析。要求学生掌握古代汉语单音词、复音词、同义词的特点，以提高阅读古文的水平。 一、字和词的区别。 用现代语言学的观点来看，字是书写符号，是组成词的要素，而 词则是最小的能够独立活动的有意义成分，两者之间不能划等号。 在古汉语中，有些字的本身就是词，如“上” “天”“香”“祸” “山”“牛”“热”“乐”等，因为它们都具有作为一个词的条件：是 最小的成分，都有意义，都能独立活动。有些字本身不能成为词，必须与别的字结合在一起才能构成词，如“葡萄” “苜蓿”“蟋蟀”等连 绵词。有些字在有的情况下是词，有的情况下仅仅是字，如“犹”和“豫”都是词。“犹”有“像 , 一样”的意思，“豫”有事先的意思，它们都能够独立运用，具备词的条件，但在“犹豫”一词里，它们各自不能独立活动，不表示任何意义，仅仅起记录音节的作用。 二、单音词概说 （一）概念
由一个音节构成的词称为单音词，一般是用一个字记录，如“学”“而”“时”“习”等。 （二）古代汉语词汇中，单音词占着绝对的优势 1.古代汉语的词汇以单音词为主，而现代汉语的词汇以复音词为 主。 例一： 韩厥梦子与谓己曰：“旦辟左右。”故中御而从齐侯。邴夏曰：“射其御者，君子也。”公曰：“谓之君子而射之，非礼也。”射其左，越于车下；射其右，毙于车中。綦毋张丧车，从韩厥曰：“请寓乘。”从左右，皆肘之，使立于后。韩厥俛定其右。 《齐晋鞌 之战》（教材 32 页） 这段文字共计83 个字， 73 个词，其中单音词64 个，复音词 9个，分别是韩厥 3 次、子与 1 次、齐侯 1 次、邴夏 1 次、綦毋张 1 次、 君子 2 次，复音词占 88%。 例二： 秦国轻而无礼必败。 这句话译为现代汉语为“秦国军队轻浮而且没有礼节必定失败” ，字数增加 1 倍。 从以上两例可以看出，古代汉语的词汇以单音词为主，而现代汉 语的词汇以复音词为主。 2.古汉语词汇中单音词占绝对的优势，并不是偶然的，而是有着深刻
1.表示各种“目的”，用for （1）What do you study English for 你为什么要学英语？ （2）went to france for holiday. 她到法国度假去了。 （3）These books are written for pupils. 这些书是为学生些的。 （4）hope for the best, prepare for the worst. 作最好的打算，作最坏的准备。 2．“对于”用for （1）She has a liking for painting. 她爱好绘画。 （2）She had a natural gift for teaching. 她对教学有天赋/ 3．表示“赞成、同情”，用for （1）Are you for the idea or against it 你是支持还是反对这个想法？ （2）He expresses sympathy for the common people.. 他表现了对普通老百姓的同情。 （3）I felt deeply sorry for my friend who was very ill. 4. 表示“因为，由于”（常有较活译法），用for （1）Thank you for coming. 谢谢你来。
（2）France is famous for its wines. 法国因酒而出名。 5．当事人对某事的主观看法，“对于（某人），对…来说”，（多和形容词连用），用介词to，不用for. （1）He said that money was not important to him. 他说钱对他并不重要。 （2）To her it was rather unusual. 对她来说这是相当不寻常的。 （3）They are cruel to animals. 他们对动物很残忍。 6．和fit, good, bad, useful, suitable 等形容词连用，表示“适宜，适合”，用for。（1）Some training will make them fit for the job. 经过一段训练，他们会胜任这项工作的。 （2）Exercises are good for health. 锻炼有益于健康。 （3）Smoking and drinking are bad for health. 抽烟喝酒对健康有害。 （4）You are not suited for the kind of work you are doing. 7. 表示不定式逻辑上的主语，可以用在主语、表语、状语、定语中。 （1）It would be best for you to write to him. （2） The simple thing is for him to resign at once.
1.两者都可以引出间接宾语，但要根据不同的动词分别选用介词to 或for：(1) 在give, pass, hand, lend, send, tell, bring, show, pay, read, return, write, offer, teach, throw 等之后接介词to。 如： 请把那本字典递给我。 正：Please hand me that dictionary. 正：Please hand that dictionary to me. 她去年教我们的音乐。 正：She taught us music last year. 正：She taught music to us last year. (2) 在buy, make, get, order, cook, sing, fetch, play, find, paint, choose,prepare, spare 等之后用介词for 。如： 他为我们唱了首英语歌。 正：He sang us an English song. 正：He sang an English song for us. 请帮我把钥匙找到。 正：Please find me the keys. 正：Please find the keys for me. 能耽搁你几分钟吗(即你能为我抽出几分钟吗)? 正：Can you spare me a few minutes? 正：Can you spare a few minutes for me? 注：有的动词由于搭配和含义的不同，用介词to 或for 都是可能的。如：do sb a favour＝do a favour for sb 帮某人的忙 do sb harm＝do harm to sb 对某人有害
1. 两者都可以引出间接宾语，但要根据不同的动词分别选用介词to 或for： (1) 在give, pass, hand, lend, send, tell, bring, show, pay, read, return, write, offer, teach, throw 等之后接介词to。 如： 请把那本字典递给我。 正：Please hand me that dictionary. 正：Please hand that dictionary to me. 她去年教我们的音乐。 正：She taught us music last year. 正：She taught music to us last year. (2) 在buy, make, get, order, cook, sing, fetch, play, find, paint, choose,prepare, spare 等之后用介词for 。如： 他为我们唱了首英语歌。 正：He sang us an English song. 正：He sang an English song for us. 请帮我把钥匙找到。 正：Please find me the keys. 正：Please find the keys for me. 能耽搁你几分钟吗(即你能为我抽出几分钟吗)? 正：Can you spare me a few minutes? 正：Can you spare a few minutes for me? 注：有的动词由于搭配和含义的不同，用介词to 或for 都是可能的。如： do sb a favou r do a favour for sb 帮某人的忙 do sb harnn= do harm to sb 对某人有害
第27卷第3期唐山师范学院学报2005年5月Vol. 27 No.3 Journal of Tangshan Teachers College May 2005 奈达翻译理论初探 尹训凤1，王丽君2 （1.泰山学院外语系，山东泰安 271000；2.唐山师范学院教务处，河北唐山 063000） 摘要：奈达的翻译理论对于翻译实践有很强的指导作用：从语法分析角度来讲，相同的语法结构可能具有完全不同的含义；词与词之间的关系可以通过逆转换将表层形式转化为相应的核心句结构；翻译含义是翻译成败的关键所在。 关键词：奈达；分析；转换；重组；核心句 中图分类号：H315.9 文献标识码：A 文章编号：1009-9115（2005）03-0034-03 尤金?奈达是美国当代著名翻译理论家，也是西方语言学派翻译理论的主要代表，被誉为西方“现代翻译理论之父”。他与塔伯合著的《翻译理论与实践》对翻译界影响颇深。此书说明了中国与西方译界人士思维方式的巨大差别：前者是静的，崇尚“信、达、雅”，讲究“神似”，追求“化境”；后者是动的，将语言学、符号学、交际理论运用到翻译研究当中，提倡“动态对等”，注重读者反应。中国译论多概括，可操作性不强；西方译论较具体，往往从点出发。他在该书中提到了动态对等，详细地描述了翻译过程的三个阶段：分析、转换和重组，对于翻译实践的作用是不言而喻的。笔者拟结合具体实例，从以下角度来分析其理论独到之处。 一 一般来说，结构相同的词组、句子，其语法意义是相同或相近的。然而奈达提出，同样的语法结构在许多情况下可以有不同的含义。“名词+of+名词”这一语法结构可以对此作最好的阐释。如下例： （1）the plays of Shakespeare/ the city of New York/ the members of the team/ the man of ability/ the lover of music/ the order of obedience/ the arrival of the delegation 在以上各个词组中，假设字母A和B分别代表一个名词或代词，它们之间存在着不同的关系。在the plays of Shakespeare 中，Shakespeare是施事，plays是受事，用公式表示就是“B writes A”；在the city of New York中，city和New York是同位关系，用公式表示就是“A is B”；the members of the team中，members和team是所属关系，即“A is in the B”；在the man of ability中，“B is A’s characteristic”；在the lover of music中，lover表示的是活动，即动作，music是它的受事，因此可以理解为（he/she）loves the music, 用公式表示就是“X does A to B”（X施A于B）或“B is the goal of A”（B为A的受事）；在the order of obedience中，obedience表示的是活动，order是它的受事，因此用公式表示就是“X does B to A”（X施B于A）或“A is the goal of B”（A为B的受事）；在the arrival of the delegation中，arrival表示动作，而delegation是动作的发出者，所以是“B does A”。 因此它们的结构关系如下所示： the plays of Shakespeare——Shakespeare wrote the plays. the city of New York——The city is New York. the members of the team——The members are in the team. the man of ability——The man is able. the lover of music——(He/She) loves the music. the order of obedience——(People) obey the order. the arrival of the delegation——The delegation arrives. ────────── 收稿日期：2004-06-10 作者简介：尹训凤（1976-），女，山东泰安人，泰山学院外语系教师，现为天津外国语学院研究生部2003级研究生，研究方向为翻译理论与实践。 - 34 -
to和for的用法有什么不同（一） 一、引出间接宾语时的区别 两者都可以引出间接宾语，但要根据不同的动词分别选用介词to 或for，具体应注意以下三种情况： 1. 在give, pass, hand, lend, send, tell, bring, show, pay, read, return, write, offer, teach, throw 等之后接介词to。如： 请把那本字典递给我。 正：Please hand me that dictionary. 正：Please hand that dictionary to me. 她去年教我们的音乐。 正：She taught us music last year. 正：She taught music to us last year. 2. 在buy, make, get, order, cook, sing, fetch, play, find, paint, choose, prepare, spare 等之后用介词for 。如： 他为我们唱了首英语歌。 正：He sang us an English song. 正：He sang an English song for us. 请帮我把钥匙找到。 正：Please find me the keys. 正：Please find the keys for me. 能耽搁你几分钟吗(即你能为我抽出几分钟吗)? 正：Can you spare me a few minutes?
正：Can you spare a few minutes for me? 3. 有的动词由于用法和含义不同，用介词to 或for 都是可能的。如： do sb a favor＝do a favor for sb 帮某人的忙 do sb harm＝do harm to sb 对某人有害 在有的情况下，可能既不用for 也不用to，而用其他的介词。如： play sb a trick＝play a trick on sb 作弄某人 请比较： play sb some folk songs＝play some folk songs for sb 给某人演奏民歌 有时同一个动词，由于用法不同，所搭配的介词也可能不同，如leave sbsth 这一结构，若表示一般意义的为某人留下某物，则用介词for 引出间接宾语，即说leave sth for sb；若表示某人死后遗留下某物，则用介词to 引出间接宾语，即说leave sth to sb。如： Would you like to leave him a message? / Would you like to leave a message for him? 你要不要给他留个话？ Her father left her a large fortune. / Her father left a large fortune to her. 她父亲死后给她留下了一大笔财产。 二、表示目标或方向的区别 两者均可表示目标、目的地、方向等，此时也要根据不同动词分别对待。如： 1. 在come, go, walk, move, fly, ride, drive, march, return 等动词之后通常用介词to 表示目标或目的地。如： He has gone to Shanghai. 他到上海去了。 They walked to a river. 他们走到一条河边。
奈达翻译理论简介 （一）奈达其人尤金?奈达（EugeneA.Nida）1914年出生于美国俄克勒荷马州，当代著名语言学家、翻译家和翻译理论家。也是西方语言学派翻译理论的主要代表，被誉为西方“现代翻译理论之父”。尤金是当代翻译理论的主要奠基人，其理论核心是功能对等。 尤金先后访问过90个国家和地区，并著书立说，单独或合作出版了40多部书，比较著名的有《翻译科学探索》、《语言与文化———翻译中的语境》等，他还发表论文250余篇，是世界译坛的一位长青学者。他还参与过《圣经》的翻译工作。他与塔伯合著的《翻译理论与实践》对翻译界影响颇深。此书说明了中国与西方译界人士思维方式的巨大差别：前者是静的，崇尚“信、达、雅”，讲究“神似”，追求“化境”；后者是动的，将语言学、符号学、交际理论运用到翻译研究当中，提倡“动态对等”，注重读者反应。中国译论多概括，可操作性不强；西方译论较具体，往往从点出发。他在该书中提到了动态对等，详细地描述了翻译过程的三个阶段：分析、转换和重组，对于翻译实践的作用是不言而喻的。 （二）奈达对翻译的定义 按照奈达的定义：“所谓翻译，是指从语义到文体（风格）在译语中用最切近而又最自然的对等语再现 源语的信息。”其中，“对等”是核心，“最切近”和“最自然”都是为寻找对等语服务的。奈达从社会语言学和语言交际功能的观点出发，认为必须以读者的反应作为衡量译作是否正确的重要标准。翻译要想达到预期的交际目的，必须使译文从信息内容、说话方式、文章风格、语言文化到社会因素等方面尽可能多地反映出原文的面貌。他试图运用乔姆斯基的语言学理论建立起一套新的研究方法。他根据转换生成语法，特别是其中有关核心句的原理，提出在语言的深层结构里进行传译的设想。 奈达提出了词的4种语义单位的概念，即词具有表述事物、事件、抽象概念和关系等功能。这4种语义单位是“核心”，语言的表层结构就是以“核心”为基础构建的，如果能将语法结构归纳到核心层次，翻译过程就可最大限度地避免对源语的曲解。按照4种语义单位的关系，奈达将英语句子归结为7个核心句：（1）Johnranquickly.（2）JohnhitBill.（3）JohngaveBillaball.（4）Johnisinthehouse.（5）Johnissick.（6）Johnisaboy.（7）Johnismyfather. （三）奈达翻译理论的经历阶段 奈达翻译理论的发展经历过三个阶段，分别是描写语言阶段、交际理论阶段和和社会符号学阶段。 第一个阶段始于1943年发表《英语句法概要》，止于1959年发表《从圣经翻译看翻译原则》。这一阶段是奈达翻译思想及学术活动的初期。 第二阶段始于1959年发表的《从圣经翻译看翻译原则》，止于1969年出版的《翻译理论与实践》。主要著作有《翻译科学探索》、《信息与使命》。在这10年中，奈达确立了自己在整个西方翻译理论界的权威地位。1964年出版的《翻译科学探索》标志着其翻译思想发展过程中一个最重要的里程碑。第三阶段始于70年代，奈达通过不断修正和发展自己翻译理论创建了新的理论模式———社会符号学模式。奈达在继承原有理论有用成分的基础上，将语言看成一种符号现象，并结合所在社会环境进行解释。在《从一种语言到另一种语言》一书中，奈达强调了形式的重要性，认为形式也具有意义，指出语言的修辞特征在语言交际及翻译中的重要作用，并且用“功能对等”取代了“动态对等”的提法，是含义更加明确。 三、对奈达翻译理论的评价 （一）贡献 奈达是一位硕果累累的翻译理论家。可以说，在两千年的西方翻译思想发展史上，奈达的研究成果之丰是名列前茅的。他的研究范围从翻译史、翻译原则、翻译过程和翻译方法到翻译教学和翻译的组织工作，从口译到笔译，从人工翻译到机器翻译，从语义学到人类文化学，几乎无所不包，从而丰富并拓展了西方的翻译研究领地。 奈达的理论贡献，主要在于他帮助创造了一种用新姿态对待不同语言和文化的气氛，以增进人类相互之间的语言交流和了解。他坚持认为：任何能用一种语言表达的东西都能够用另一种语言来表达；在语言之间、文化之间能通过寻找翻译对等语，以适当方式重组原文形式和语义结构来进行交际。因此也说明，某
202X中考英语：to和for的区别与用法中考栏目我为考生们整理了“202X中考英语：to和for的区别与用法”，希望能帮到大家，想了解更多考试资讯，本网站的及时更新哦。 202X中考英语：to和for的区别与用法 to和for的区别与用法是什么 一般情况下, to后面常接对象; for后面表示原因与目的为多。 Thank you for helping me. Thanks to all of you. to sb. 表示对某人有直接影响比如，食物对某人好或者不好就用to; for 表示从意义、价值等间接角度来说，例如对某人而言是重要的，就用for. for和to这两个介词，意义丰富，用法复杂。这里仅就它们主要用法进行比较。 1. 表示各种“目的” 1. What do you study English for? 你为什么要学英语? 2. She went to france for holiday. 她到法国度假去了。 3. These books are written for pupils. 这些书是为学生些的。 4. hope for the best, prepare for the worst. 作最好的打算，作最坏的准备。
2.对于 1.She has a liking for painting. 她爱好绘画。 2.She had a natural gift for teaching. 她对教学有天赋。 3.表示赞成同情，用for不用to. 1. Are you for the idea or against it? 你是支持还是反对这个想法? 2. He expresses sympathy for the common people.. 他表现了对普通老百姓的同情。 3. I felt deeply sorry for my friend who was very ill. 4 for表示因为，由于(常有较活译法) 1.Thank you for coming. 谢谢你来。 2. France is famous for its wines. 法国因酒而出名。 5.当事人对某事的主观看法，对于(某人)，对?来说(多和形容词连用)用介词to，不用for.. He said that money was not important to him. 他说钱对他并不重要。 To her it was rather unusual. 对她来说这是相当不寻常的。 They are cruel to animals. 他们对动物很残忍。
to , of 和for的区别 1.to有到的意思，常常和go，come，get连用引出地点。Go to school , go to the shop , go to the cinema. 常见的短语：the way to 去---的路 On one’s way to 在某人去---的路上 以上的用法中，当地点是副词home，here，there等是to 要去掉。如：get home，the way here To后跟动词原形，是不定式的标志 It is +形容词+(for/of +人+)to do sth.(括号内部分可以省略) It is easy for me to learn English. It is very kind of you to lend me your money. 当形容词表示人的行为特征时用of表示to do的性质时用for Want, hope ,decide, plan , try , fail等词后跟to do I want to join the swimming club. Would like to do I’d like to play basketball with them. It is time to have a break. Next to , close to , from ---to--- 2.for 为，表示目的。 Thank you for Buy sth for sb =buy sb sth It is time for bed. Here is a letter for you.
I will study for our country. 3.of表示所属关系意思是：---的 a map of the world a friend of mine
To Equivalence and Beyond: Reflections on the Significance of Eugene A. Nida for Bible Translating1 Kenneth A. Cherney, Jr. It’s been said, and it may be true, that there are two kinds of people—those who divide people into two kinds and those who don’t. Similarly, there are two approaches to Bible translation—approaches that divide translations into two kinds and those that refuse. The parade example of the former is Jerome’s claim that a translator’s options are finally only two: “word-for-word” or “sense-for-sense.”2 Regardless of whether he intended to, Jerome set the entire conversation about Bible translating on a course from which it would not deviate for more than fifteen hundred years; and some observers in the field of translation studies have come to view Jerome’s “either/or” as an unhelpful rut from which the field has begun to extricate itself only recently and with difficulty. Another familiar dichotomy is the distinction between “formal correspondence” translating on one hand and “dynamic equivalence” (more properly “functional equivalence,” on which see below) on the other. The distinction arose via the work of the most influential figure in the modern history of Bible translating: Eugene Albert Nida (1914-2011). It is impossible to imagine the current state of the field of translation studies, and especially Bible translating, without Nida. Not only is he the unquestioned pioneer of modern, so-called “meaning-based” translating;3 he may be more responsible than any other individual for putting Bibles in the hands of people around the world that they can read and understand. 1 This article includes material from the author’s doctoral thesis (still in progress), “Allusion as Translation Problem: Portuguese Versions of Second Isaiah as Test Case” (Stellenbosch University, Drs. Christo Van der Merwe and Hendrik Bosman, promoters). 2 Jerome, “Letter to Pammachius,” in Lawrence Venuti, ed., The Translation Studies Reader, 2nd ed. (NY and London: Routledge, 2004), p. 23. 3 Nigel Statham, "Nida and 'Functional Equivalence': The Evolution of a Concept, Some Problems, and Some Possible Ways Forward," Bible Translator 56, no. 1 (2005), p. 39.