AUTHOR=Feng Chunlin , Gao Mengdi , Jiang Weiyan , Shi Weina , Li Anqi , Liu Shuang , Zhang Lei , Zhang Xueya , Li Qiaoling , Lin Hailong , Lu Junwan , Li Kewei , Zhang Hailin , Hu Yunliang , Bao Qiyu , Lin Xi 

TITLE=Identification of a novel aminoglycoside O-nucleotidyltransferase AadA33 in Providencia vermicola

JOURNAL=Frontiers in Microbiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.990739

DOI=10.3389/fmicb.2022.990739

ISSN=1664-302X

ABSTRACT=<p>A novel chromosome-encoded aminoglycoside <italic>O</italic>-nucleotidyltransferase AadA33 was identified in <italic>Providencia vermicola</italic> strain P13. The AadA33 shares the highest amino acid identity of 51.28% with the function characterized AadA31. Antibiotic susceptibility testing and enzyme kinetics analysis revealed that the function of AadA33 is to mediate spectinomycin and streptomycin resistance. The recombinant strain harboring <italic>aadA33</italic> (pUCP20-<italic>aadA33</italic>/<italic>Escherichia coli</italic> DH5α) displayed &gt;256- and 128-fold increases in the minimum inhibitory concentration levels to spectinomycin and streptomycin, respectively, compared with the control strains pUCP20/DH5α. Enzyme kinetic parameters manifested the substrate of AadA33 including spectinomycin and streptomycin, with <italic>k</italic><sub>cat</sub>/<italic>K</italic><sub>m</sub> of 3.28 × 10<sup>4</sup> (M<sup>−1</sup> s<sup>−1</sup>) and 3.37 × 10<sup>4</sup> (M<sup>−1</sup> s<sup>−1</sup>), respectively. Bioinformatics analysis revealed its structural mechanism of antimicrobial resistance, genetic context, and phylogenetic relationship with other aminoglycoside <italic>O</italic>-nucleotidyltransferases. This study of AadA33 contributed to understanding the function and resistance mechanism of aminoglycoside <italic>O</italic>-nucleotidyltransferase.</p>