Molecular and phenotypic features for identification of the opportunistic pathogens Ochrobactrum spp.
Molecular and phenotypic features for identification of the opportunistic pathogens Ochrobactrum spp.
复制标题
DOI：
10.1099/jmm.0.46116-0
复制
发表时间：
2005-10-01
影响因子：
3
通讯作者：
Jumas-Bilak, E
中科院分区：
文献类型：
--
作者：
Teyssier, C;Marchandin, H;Jumas-Bilak, E
在Ochrobactrum属的6个种中，人Ochrobactrum和中间Ochrobactrum目前被报道为人类的条件致病菌。由于物种鉴定主要基于16S rDNA分析，因此本研究的目的是寻找其他可用于Ochrobactrum物种鉴别的特征。对35株临床分离株进行了核糖体分型、形态和生化分析以及药敏试验，这些临床分离株首次通过16S rDNA测序鉴定到物种水平。对5种Ochrobactrum的模式菌株和参考菌株进行了比较分析。商业鉴定系统，如API 20NE和VITEK 2，测试了它们鉴定人嗜铬杆菌和检测嗜铬杆菌属其他成员的能力。一种改进的麦曲霉鉴定方法。通过常规医学微生物学方法提出：分离出一株对除亚胺培南以外的所有β-内酰胺类抗生素都耐药的非挑剔非发酵酶阳性革兰氏阴性杆菌，API 20NE系统确认了大多数菌株的属鉴定，而使用ID-GNB卡的VITEK 2系统功能较弱。可将尿素酶活性、菌落粘液性、45℃下在胰酶消化的大豆琼脂上生长以及对粘菌素、妥布霉素和奈替米星的敏感性作为区分人间棘球线虫和中间人间丝虫的鉴别特征。然而，最终的鉴定取决于基因分型方法。
Among the six species characterized within the genus Ochrobactrum, Ochrobactrum anthropi and Ochrobactrum intermedium are currently reported as opportunistic pathogens in humans. Since the species identification is mainly based on 16S rDNA analysis, the aim of this study was to search for other characteristics useful for Ochrobactrum species discrimination. Ribotyping, morphological and biochemical analyses, and antimicrobial susceptibility testing were performed for a panel of 35 clinical isolates, first identified to the species level using 16S rDNA sequencing. Type and reference strains of five Ochrobactrum species were comparatively analysed. Commercial identification systems such as API 20NE and VITEK 2 were tested for their ability to identify Ochrobactrum anthropi and to detect other members of the genus Ochrobactrum. An improved protocol for the identification of Ochrobactrum spp. by routine medical microbiology practices is proposed: isolation of a non-fastidious non-fermenting oxidase-positive Gram-negative rod resistant to all beta-lactams except imipenem indicates the genus Ochrobactrum, and the API 20NE system confirms the genus identification for most strains, whereas the VITEK 2 system using ID-GNB cards was less powerful. Urease activity, the mucoidy of the colonies, growth at 45 degrees C on tryptic soy agar, and susceptibility to colistin, tobramycin and netilmicin should be considered as differential characteristics for identification of O. anthropi and O. intermedium to the species level. However, definitive identification depends on genotyping methods.