Ge Yumei, Chen Xuebo, Huang Yanying, Lyu Huoyang, Zhao Zhao, Zhou Yonglie
Center of Clinical Laboratory Medicine, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou 310014, China.
Wenzhou Medical University School of Laboratory Medicine, Wenzhou 325035, China.
Zhejiang Da Xue Xue Bao Yi Xue Ban. 2017 Jul 25;46(4):413-420. doi: 10.3785/j.issn.1008-9292.2017.08.11.
To investigate the drug resistance, β-lactamase-encoding genes and protoporphyrin ferrochelatase-encoding genes of , and to explore its structure and pathogenic function.
The strain was isolated by plate streaking method and identified by automatic bacteria detection system and 16S RNA gene PCR. Microdilution method was applied for drug susceptibility test. β-lactamases, extended spectrum β-lactamases (ESBL) and carbapenemases were detected using nitrocefin-disk, Kirby-Bauer disk, and Hodge test, respectively. Five β-lactamase-encoding genes and protoporphyrin ferrochelatase-encoding gene of the isolate were amplified by PCR for sequencing. Bioinformatic softwares were used to analyze the structure and function of the product of protoporphyrin ferrochelatase-encoding gene.
A strain belonging to was isolated. This isolate was sensitive to cefepime, ciprofloxacin, ofloxacin and tigecycline, but resistant to five penicillins, four cephalosporins and two carbapenems antibiotics. The isolate produced β-lactamases but did not produce ESBL and carbapenemases. The isolate had five distinct β-lactamase-encoding genes and protoporphyrin ferrochelatase-encoding gene. The product of protoporphyrin ferrochelatase-encoding gene contained two functional domains of protoporphyrin ferrochelatase belonging to type Ⅱ chelatase superfamily that presented the most closely genetic relationship with the protoporphyrin ferrochelatase of .
The isolate of has a higher resistance to β-lactam antibiotics and its β-lactamase-encoding genes are different with the common bacterial β-lactamase-encoding genes. Protoporphyrin ferrochelatase may act as an important virulence factor of .
研究[具体菌种名称未给出]的耐药性、β-内酰胺酶编码基因和原卟啉亚铁螯合酶编码基因，并探索其结构和致病功能。
采用平板划线法分离菌株，通过自动细菌检测系统和16S RNA基因PCR进行鉴定。采用微量稀释法进行药敏试验。分别使用硝基头孢菌素纸片法、 Kirby-Bauer纸片法和 Hodge试验检测β-内酰胺酶、超广谱β-内酰胺酶（ESBL）和碳青霉烯酶。通过PCR扩增该分离株的5个β-内酰胺酶编码基因和原卟啉亚铁螯合酶编码基因进行测序。使用生物信息学软件分析原卟啉亚铁螯合酶编码基因产物的结构和功能。
分离出1株属于[具体菌种名称未给出]的菌株。该分离株对头孢吡肟、环丙沙星、氧氟沙星和替加环素敏感，但对5种青霉素、4种头孢菌素和2种碳青霉烯类抗生素耐药。该分离株产生β-内酰胺酶，但不产生ESBL和碳青霉烯酶。该分离株有5个不同的β-内酰胺酶编码基因和原卟啉亚铁螯合酶编码基因。原卟啉亚铁螯合酶编码基因产物包含属于Ⅱ型螯合酶超家族的原卟啉亚铁螯合酶的两个功能结构域，与[具体菌种名称未给出]的原卟啉亚铁螯合酶具有最密切的遗传关系。
[具体菌种名称未给出]分离株对β-内酰胺类抗生素具有较高耐药性，其β-内酰胺酶编码基因与常见细菌的β-内酰胺酶编码基因不同。原卟啉亚铁螯合酶可能是[具体菌种名称未给出]的重要毒力因子。
