一种分离自茶卡盐湖的盐单胞菌Halomonas chakariensis strain CH40^(T)的新种鉴定  

Identification of a new species of Halomonas chakariensis strain CH40^(T) isolated from Chaka Salt Lake

作　　者：崔甜琦 张田田 唐超群[1] 朱德锐[1] 邢江娃 Cui Tianqi;Zhang Tiantian;Tang Chaoqun;Zhu Derui;Xing Jiangwa(Research Center of Basic Medical Sciences,Medical College of Qinghai University,Xining 810001,China)

机构地区：[1]青海大学医学部,基础医学研究中心,西宁810001

出　　处：《中国高原医学与生物学杂志》2023年第3期185-194,共10页Journal of Chinese High Altitude Medicine & Biology

基　　金：国家自然科学基金项目(31860030);国家人社部2021年度高层次留学人才回国资助项目;青海大学青年科研基金项目(2022-QYY-15)。

摘　　要：目的为挖掘青藏高原超盐盐湖中的嗜盐微生物新种资源,对从青海茶卡盐湖水样和底泥混合物中分离到的一株细菌CH40^(T)进行新种鉴定。方法对提取菌株的16S rRNA基因进行扩增测序,并在GenBank、EzBiocloud网站上进行BLAST比对,利用MEGA 7软件构建系统发育树做新种鉴定。利用光学显微镜和扫描电镜观察菌株形态,采用分光光度法测定不同培养条件下的菌株生长情况并判断其最适生长条件,采用试剂盒法测定菌株的生理生化特征。采用Illumina Hiseq、PacBio RS II单分子实时(SMRT)系统对菌株进行全基因组测序,通过ANI、dDDH分析确定CH40^(T)的新种地位。采用16S rRNA和gyrB、rpoD基因序列构建系统发育树,确定CH40^(T)的系统发育地位。结果经16S rRNA测序比对分析表明,菌株CH40^(T)属于盐单胞菌属。菌株为革兰氏染色阴性菌,呈杆状,需氧,含鞭毛。菌落呈乳白色,圆形,光滑湿润,能够在温度为10℃~40℃(30℃~37℃为佳)、酸碱度为6.0~10.0(最适7.0)和盐度为1%~20%(2%~7%为佳,w/v)的条件下生长。基因组不含质粒,全长3.76 Mbp,与系统发育地位相近菌株的全基因组ANI、dDDH分析结果均低于ANI 95%和dDDH 70%的新种鉴定阈值。结论菌株CH40T是Halomonas属的一个新物种,为中度嗜盐菌,命名为茶卡盐单胞菌(Halomonas chakariensis)。Objective A new strain of bacteria CH40^(T) isolated from the mixture of water and sediment of Chaka Salt Lake was identified to explore the new species of halophilic microbial resources in the hypersaline salt lakes of the Qinghai-Tibet Plateau.Methods The 16S rRNA gene of the strain CH40^(T) was extracted for amplification and sequencing.BLAST comparison was performed on the websites GenBank and EzBiocloud.A phylogenetic tree was constructed using software MEGA 7 for new species identification.The morphology of the strain was observed by light microscopy and scanning electron microscopy.The growth of CH40^(T) under diferent culture conditions was determined by spectrophotometry and the most suitable growth conditions were determined.Its physiological and biochemical characteristics were determined using commercially available kits.The whole genome of the strain was sequenced using Ilumina Hiseq and PacBio RSⅡ Single Molecule Real Time(SMRT)systems.The new species status of CH40^(T) was determined by ANI and dDDH analysis.A phylogenetic tree was constructed using 16S rRNA,gyrB and rpoD gene sequences to determine the phylogenetic status of CH40^(T).Results According to 16S rRNA sequencing and comparison analysis,CH40^(T) belongs to the genus Halomonas.The strain was Gram-negative,rod-shaped,aerobic and flagellated.The colonies were creamy white,round,smooth and moist.It was able to grow under the conditions of 10℃~40℃(30℃~37℃ preferred),pH 6.0~10.0(7.0 preferred)and 1%~20% NaCl(2%~7% preferred,w/v).The genome was plasmid-free with a total length of 3.76 Mbp.The whole genome ANI and dDDH analysis results of strains with similar phylogenetic status were lower than the new species identification threshold of 95% ANI and 70% dDDH.Conclusions CH40'is a new species of Halomonas,a moderately halophilic bacterium,named Halomonas chakariensis.

关 键 词：盐单胞菌 新种鉴定 16SrRNA 全基因组测序 系统发育分析 

分 类 号：Q93-331[生物学—微生物学]