Identification and Characterization of a Novel Chromosomal Aminoglycoside 2′-N-Acetyltransferase, AAC(2′)-If, From an Isolate of a Novel Providencia Species, Providencia wenzhouensis R33

作者：Kexin Zhou, Jialei Liang, Xu Dong, Peiyao Zhang, Chunlin Feng, Weina Shi, Mengdi Gao, Qiaoling Li, Xueya Zhang, Junwan Lu, Xi Lin, Kewei Li, Hailin Zhang, Mei Zhu, Qiyu Bao · 发表于：Frontiers in Microbiology · 年份：2021 · DOI：10.3389/fmicb.2021.711037 · 被引用次数：14 · 研究领域：Antibiotic Resistance in Bacteria、Pharmaceutical and Antibiotic Environmental Impacts、Bacteriophages and microbial interactions

Multidrug-resistant bacteria from different sources have been steadily emerging, and an increasing number of resistance mechanisms are being uncovered. In this work, we characterized a novel resistance gene named aac(2′)-If from an isolate of a novel Providencia species, Providencia wenzhouensis R33 (CCTCC AB 2021339). Susceptibility testing and enzyme kinetic parameter analysis were conducted to determine the function of the aminoglycoside 2′- N -acetyltransferase. Whole-genome sequencing and comparative genomic analysis were performed to elucidate the molecular characteristics of the genome and the genetic context of the resistance gene-related sequences. Among the functionally characterized resistance genes, AAC(2′)-If shares the highest amino acid sequence identity of 70.79% with AAC(2′)-Ia. AAC(2′)-If confers resistance to several aminoglycoside antibiotics, showing the highest resistance activity against ribostamycin and neomycin. The recombinant strain harboring aac(2′)-If (pUCP20- aac(2′)-If /DH5α) showed 256- and 128-fold increases in the minimum inhibitory concentration (MIC) levels to ribostamycin and neomycin, respectively, compared with those of the control strains (DH5α and pUCP20/DH5α). The results of the kinetic analysis of AAC(2′)-If were consistent with the MIC results of the cloned aac(2′)-If with the highest catalytic efficiency for ribostamycin ( k cat /K m ratio = [3.72 ± 0.52] × 10 4 M –1 ⋅ s –1 ). Whole-genome sequencing demonstrated that the aac(2′)-I...