[基金项目] 浙江省档案局科研项目(2007-9)[作者简介] 燕勇(1974-),男,学士,主管技师,主要从事微生物检验工作。
=论著>r DNA -I TS 序列分析在真菌鉴定中的应用燕勇,李卫平,高雯洁,沈志英,王恒辉,陈黎霞(浙江省嘉兴市疾病预防控制中心,浙江嘉兴 314050)[摘要] 目的:通过对3株真菌的rDNA -I T S 序列进行分析,以探讨、说明基于核糖体RNA 基因(即rDNA )内转录间隔区(In ternal T ranscribed Spacer ,I T S)的多态性的序列分析(rDNA -I T S 序列分析)在真菌鉴定中的应用。
方法:通过PCR扩增与测序的方法测得待检真菌菌株的rDNA -ITS 序列,从GENBANK 获取相似序列,使用BLA S T 和DNAMAN 工具对r DNA -I TS 序列进行比对分析。
结果:1号真菌菌株与X y l a riales sp 1LM 40(属炭角菌目)同源性高,但尚不能鉴定到具体的属、种;2号真菌菌株可鉴定到种,为草酸青霉Penic illi u m oxa li cu m;3号真菌菌株可鉴定到种内组水平,为近平滑假丝酵母III 组(最新命名为Candida m etaps il o si s)。
结论:相对于传统的真菌形态学鉴定方法,rDNA -ITS 序列分析用于真菌鉴定更客观、省时、简便、快速,但目前也存在一定的应用限制(受基因库的完善程度、高度同源性序列的多少以及具体物种ITS 区的可变程度等影响)并不能鉴定出所有真菌,宜与传统的形态学鉴定方法相结合用于真菌鉴定。
[关键词] r DNA;内转录间隔区(ITS);PCR;测序;真菌;鉴定[中图分类号] R 44615 [文献标识码] A [文章编号] 1004-8685(2008)10-1958-04Application of r DNA I TS sequence analysis in fungus identificationYan Yong,L iW ei -p ing ,Gao W ei -jie ,Shen Zhi -y in g,W ang H eng-hui ,Chen L i -x iao (Jiax ing Cente r for D i sease Contro l and P reventi on ,Ji ax i ng 314050,Chi na)[Abstract] O bjective :T o introduce and illu m i nate t he applicati on o f r DNA I T S sequence ana l ysis i n f ungus i dentifica ti on on basis o f sequence and l eng t h poly m orph i s m s o f i nterna l transcr i bed spacer(I TS)i n ri bosoma l RNA gene(rDNA )1M ethods :T he three pend i ng fungus stra i ns c rDNA I T S sequences tested by PCR a m plifi cati on and sequenc i ng m e t hods were analyzed and co m-pared w ith si m ilar sequences fro m G E N BANK by N CB I BLAST on li ne too l and DNAMAN so ft w are 1Resu lts :N o 11f ungus stra i n had a h i gh hom ology w it h X y l a riales sp 1L M 40,bu t w as no t yet i den tifiab le on genus or spec ies l eve l o f taxonom ic c l assifi ca -ti on 1N o 12strai n w as i den tified as P en icilliu m oxalicu m,a genus l eve l 1N o 13strai n w as i dentified as Cand i da m etapsil os i s ,ne w desi gnati on of Candida parapsilosis group III ,a g roup l eve l i n spec ies re l a ti ve l y 1Conc l u si on :Compared w ith the traditiona lm or -pho l og ical i den tificati on m ethods ,the r DNA ITS sequence ana lysis i s m ore ob j ective ,ti m e-sav ing ,convenient ,and fast for fun -gus identificati on ,butw it h so m e appli ed li m its currently 1D epended on the perfecti on deg ree o f gene database ,the nu m ber o f h i gh-deg ree homo l ogy sequence ,t he var i ability ex tent of ITS reg i on of biolog ical i nd i v i duals and so on it can be app lied 1T hen ,it does not identif y all f ung ,i and shoul d be co m bi ned w ith the trad iti ona lm orpho l og i ca l identificati on m et hods for f ungus identificati on 1[K ey words] r DNA;Inte rnal transcr i bed spacer(ITS);PCR;Sequenc i ng ;F ungus ;Identifi cation 真核生物基因组中编码核糖体的基因包括28S r DNA 、5S r DNA 、18S rDNA 和518S r DNA 4种,它们在染色体上头尾相连、串联排列,相互之间由间隔区分隔。
