College of Veterinary Medicine, Southwest University, Beibei, Chongqing, China.
Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China.
Vet Microbiol. 2022 Jul;270:109456. doi: 10.1016/j.vetmic.2022.109456. Epub 2022 May 12.
A novel chromosomally-located β-lactamase gene, bla, was identified in Riemerella anatipestifer RA-CH-1. The RASA-1, encoded by bla, was a class A extended-spectrum β-lactamase (ESBL), which shared 42.7% and 40.5% identities with the RAA-1 and CGA-1 β-lactamase, respectively. Overexpression of RASA-1 in Escherichia coli confers broad resistance to β-lactams and the purified native RASA-1 revealed ESBL-like hydrolysis activity. Blasting in GenBank showed that bla was exclusively detected in Riemerella anatipestifer. Moreover, sequence analysis revealed that this gene was located within the multi-resistance region of Riemerella anatipestifer genome.
在鸭疫里默氏杆菌 RA-CH-1 中发现了一个新型的位于染色体上的β-内酰胺酶基因 bla。由 bla 编码的 RASA-1 是一种 A 类扩展谱β-内酰胺酶（ESBL），分别与 RAA-1 和 CGA-1 β-内酰胺酶具有 42.7%和 40.5%的同一性。RASA-1 在大肠杆菌中的过表达赋予了对β-内酰胺类抗生素的广泛抗性，并且纯化的天然 RASA-1 显示出 ESBL 样的水解活性。在 GenBank 中的 Blast 显示 bla 仅在鸭疫里默氏杆菌中被检测到。此外，序列分析表明，该基因位于鸭疫里默氏杆菌基因组的多耐药区域内。
