AUTHOR=Xia Jing , Fang Liang-Xing , Cheng Ke , Xu Guo-Hao , Wang Xi-Ran , Liao Xiao-Ping , Liu Ya-Hong , Sun Jian 

TITLE=Clonal Spread of 16S rRNA Methyltransferase-Producing Klebsiella pneumoniae ST37 with High Prevalence of ESBLs from Companion Animals in China

JOURNAL=Frontiers in Microbiology

VOLUME=8

YEAR=2017

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2017.00529

DOI=10.3389/fmicb.2017.00529

ISSN=1664-302X

ABSTRACT=<p>We screened 30 <italic>Klebsiella pneumoniae</italic> isolates from dogs and cats at a single animal hospital in Guangdong Province, China. Among them, 12 <italic>K. pneumoniae</italic> strains possessed high-level resistance to amikacin and gentamicin and these were screened for 16S rRNA methyltransferase (16S-RMTase) genes. And then the genes positive isolates were detected for ESBLs (extended spectrum β-lactamases) and analyzed by pulsed-field gel electrophoresis, multilocus sequence typing, PCR-based replicon typing and plasmid analysis. The genetic profiles of <italic>rmtB</italic> were also determined by PCR mapping. The twelve 16S-RMTase gene-positive isolates were <italic>rmtB</italic> (11/30) and <italic>armA</italic> (2/30) with one isolate carrying both genes. Extended spectrum β-lactamases genes were represented by <italic>bla</italic><sub>CTX-M-55</sub> (9/12), <italic>bla</italic><sub>CTX-M-27</sub> (2/12) and <italic>bla</italic><sub>CTX-M-14</sub> (1/12). The twelve 16S-RMTase containing strains were grouped into five clonal patterns and ST37 was the most prevalent sequence type. Ten <italic>rmtB</italic>-bearing plasmids conjugated successfully and all belonged to IncN and IncF (F33:A-:B-) incompatibility groups. Nine of the transconjugants carried a 97 kb plasmid and the other harbored both ∼60 and ∼200 kb plasmids. <italic>rmtB</italic> and <italic>bla</italic><sub>CTX-M-55</sub> were present on the same plasmid and indicated the co-transfer of these two genes, with the <italic>rmtB</italic> gene showing highly relevant relationships with IS<italic>26</italic> and Tn<italic>3</italic>. Our findings suggested a high prevalence of 16S-RMTase genes in <italic>K. pneumonia</italic> ST37 from dogs and cats. Additional studies are needed to trace the evolutionary path of this type of resistance among the <italic>K. pneumonia</italic> isolates, and to determine whether they have been transferred to humans.</p>