1株血液分离的油葫芦苍白杆菌的鉴定及系统发育分析  

Identification and phylogenetic analysis of one clinical isolate of Ochrobactrum teleogrylli from human blood

作　　者：刘健龙[1] 韩德兴 李顺光 刘雅 宋春荣[1] 陈晓慰 付敏 胡琼[1] 屈平华 Liu Jianlong;Han Dexing;Li Shunguang;Liu Ya;Song Chunrong;Chen Xiaowei;Fu Min;Hu Qiong;Qu Pinghua(Laboratory Center of Hunan Children′s Hospital,Changsha 410007,China;The Second Clinic Medical College,Guangzhou University of Chinese Medicine,Guangzhou 510006,China;The Second Clinic Medical College,Guangzhou University of Chinese Medicine/Department of Laboratory Medicine,Guangdong Provincial Hospital of Chinese Medicine,Guangzhou 510006,China)

机构地区：[1]湖南省儿童医院检验中心,长沙410007 [2]广州中医药大学第二临床医学院,广州510006 [3]广州中医药大学第二临床医学院/广东省中医院检验医学部,广州510006

出　　处：《中华微生物学和免疫学杂志》2024年第8期680-688,共9页Chinese Journal of Microbiology and Immunology

基　　金：湖南省自然科学基金-科卫联合项目(2023JJ60011)。

摘　　要：目的对临床血液标本分离的细菌7712(=CGMCC 1.17031=NBRC 113783=KCTC 15766)进行生物学特性和系统进化分析,明确其分类学地位。方法观察菌株的培养特性并进行形态学、生理生化鉴定、基质辅助激光解吸电离子飞行时间质谱鉴定和基因组测序鉴定,并构建基因组发育树以分析其分类学位置。采用在线毒力基因数据库和抗生素抗性数据库,分别对分离株及近缘菌株进行基于全基因组的毒力基因和耐药基因的比较分析。结果分离株7712为脲酶阳性的需氧革兰阴性非发酵菌,VITEK GN鉴定为人苍白杆菌。16S rRNA基因序列分析显示,分离株7712与苍白杆菌属及布鲁菌属均具有较高的序列一致性;而基于全基因系统发育分析显示,分离株7712与油葫芦苍白杆菌LCB8T和嗜血苍白杆菌CCUG 38531T聚类成一个分支,并与其他苍白杆菌属细菌和布鲁菌属聚类成一个大的分支。基因组亲缘性指数分析显示,分离株7712和油葫芦苍白杆菌LCB8T的平均核苷酸一致性为98.22%,高于原核生物物种的鉴定阈值95%。分离株7712携带多种毒力基因和耐药基因,其中OCH基因可能与头孢菌素耐药有关。结论确定了1例由油葫芦苍白杆菌引起的临床感染,丰富了苍白杆菌属生物多样性信息。ObjectiveTo analyze the biological characteristics,phylogeny and the taxonomic status of strain 7712(=CGMCC 1.17031=NBRC 113783=KCTC 15766)isolated from a clinical blood sample.MethodsStrain 7712 was identified by the cultural properties,cellular and colonial morphology,physiological and biochemical reactions,matrix-assisted laser desorption ionization time-of-flight mass spectrometry system,and genome correlation index analysis.The genomic phylogenetic tree was construct to analyze the taxonomic position.The virulence factors and resistance genes of strain 7712 and related strains were then compared by the online virulence factor database and online comprehensive antibiotic research database respectively.ResultsStrain 7712 was urease negative,gram-negative nonfermenters,which was identified as Ochrobactrum anthropi by VITEK GN card.The 16S rRNA gene analysis showed that the strain was closely related to the members of genera Ochrobactrum and Brucella.The phylogenetic tree showed that strain 7712 was clustered together with Ochrobactrum teleogrylli LCB8 T and Ochrobactrum haematophilum CCUG 38531 T,along with genus Brucella and other Ochrobactrum species.The genome relatedness indexes analysis showed that the average nucleotide identity between strain 7712 and Ochrobactrum teleogrylli LCB8 T was 98.16%,which was higher than the threshold for prokaryotic species.Genetic prediction showed that strain 7712 carried several virulence-related genes and resistance-related genes,of which the existence of OCH gene might be responsible to the resistance to cephalosporin.ConclusionsA case of human infection caused by Ochrobactrum teleogrylli is identified,which would help promote the understanding of biodiversity of genus Ochrobactrum.

关 键 词：苍白杆菌 16S rRNA 全基因组测序 系统发育树 

分 类 号：R446.5[医药卫生—诊断学]