Genetic relationships amongst Enterococcus faecalis isolates from different sources as revealed by m

来源 :第七届全国微生物资源学术暨国际微生物系统与分类学研讨会 | 被引量 : 0次 | 上传用户:myskyhoney
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
  Enterococcus faecalis is one of the most important species inthe genus Enterococcus.Although some isolates are considered as human pathogens,other isolates are used in food production.It is therefore important to understand the genetic diversity and phylogenetic relationships between E.faecalis isolates from different sources.Multilocus Sequence Typing protocol(MLST)was used to compare 39 E.faecalisisolates from Chinese traditional food products(including dairy products,acidic gruel)and 4 published E.faecalisisolates from other sources including human-derived isolates.Sequences from five selected housekeeping genes(groEL,clpX,recA,rpoB and pepC)were compared and 23 unique sequence types(STs)were obtained by sequencing analysis.The value of standardized index of association of the alleles(IAs =0.1465)and network structure revealed by split-decomposition analysis indicated a high frequency of intraspecies recombination across the population of E.faecalis isolates.Phylogenetic analysis based on the sequences of the five selected MLST loci showed that the isolates belonged to five clonal complexes(CCs)and there were ten singletons.It also indicated that E.faecalis lineages exhibited clearly source-clustered distributions.Moreover,the relationship between isolates from acidic gruel and one isolate from a human-source was close.The results indicated that MLST is a valuable tool for typing E.faecalis isolates from different sources and can be used for further monitoring of evolutionary changes and population genetics.Moreover,it also suggests that more rigorous safety evaluation might be necessary when considering isolates from acidic gruel for further industrial application in food production.
其他文献
  Traditionally,strain types of bacteria are determined by multilocus sequence typing(MLST)of several housekeeping genes.In case of mixed population of noncul
会议
磷脂是一种纯天然的营养保健品,主要存在于动、植物的细胞中,是细胞膜的主要组成成分。大豆磷脂可以维持生物膜正常的结构与功能,与细胞的生长、增殖、分化、癌变紧密联系,其降解产物还参与细胞的信号转导、代谢调控,具有改善记忆、延缓衰老、调节血脂、抗肿瘤、健脑等多种生理作用。因此本实验研究大豆磷脂对学习记忆相关基因及抗氧化能力的影响,并探讨其作用机制,为大豆磷脂更好的应用提供实验依据,进而对神经细胞的保护作
该文利用国内外在无皂乳液聚合方面取得的成就,进行了微皂乳液聚合工艺研究.微皂乳液聚合是通过同时与水溶性羧基单体和非离子性单体共聚,显著降低乳化剂的用量,旨在获得一种
L-抗坏血酸(简称VC)在体内发挥着重要的生理作用,但其还原性强,极不稳定,这使得它在应用上受到了很大的限制.VC的衍生物则大大提高了它的稳定性,而不影响它的生理功能.该课题
  深海锰铁结核含有金属矿产资源和极大的经济潜力.本研究采用可培养和非培养的方法对来自南海蛟龙海山的锰铁结核进行研究.细菌克隆文库和高通量测序结果表明,Gammaproteo
会议
本文通过对荣华二采区10
期刊
第一部分用萃取体系负载有机相预分散法制备ZrO介孔材料.利用TOPO-煤油/盐酸-Zr(Ⅳ)体系的负载有机相为油相,制各出了稳定的胶质液态泡沫.冷冻条件下,利用萃取体系负载有机相
学位
  Microorganism plays a quite important role in the ecosystem of the Antarctica.This place are involved in extreme climate,such as frozen,strong wind,drought,
会议
  草螺菌(Herbaspirillum)是革兰氏阴性菌,属于Betaproteobacteria纲,因呈螺旋状且定殖在草本种子植物而得名.H.seropedicae是Herbaspirillum属的典型种.H.seropedicae,H.r
会议