AUTHOR=Hu Dakang , Li Yuming , Ren Ping , Tian Dongxing , Chen Wenjie , Fu Pan , Wang Weiwen , Li Xiaobin , Jiang Xiaofei 

TITLE=Molecular Epidemiology of Hypervirulent Carbapenemase-Producing Klebsiella pneumoniae

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=11

YEAR=2021

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2021.661218

DOI=10.3389/fcimb.2021.661218

ISSN=2235-2988

ABSTRACT=<sec><title>Objective</title><p>To investigate the overall distributions of key virulence genes in <italic>Klebsiella pneumoniae</italic>, especially the hypervirulent <italic>bla</italic><sub>KPC</sub>-positive <italic>K. pneumoniae</italic> (Hv-<italic>bla</italic><sub>KPC</sub>(+)-KP).</p></sec><sec><title>Methods</title><p>A total of 521 complete genomes of <italic>K. pneumoniae</italic> from GenBank were collected and analyzed. Multilocus sequence typing, molecular serotyping, antibiotic-resistance, virulence genes and plasmid replicon typing were investigated.</p></sec><sec><title>Results</title><p>Positive rates of virulence genes highly varied, ranging from 2.9 (<italic>c-rmpA/A2</italic>) to 99.6% (<italic>entB</italic>). Totally 207 strains presented positive <italic>fimH</italic>, <italic>mrkD</italic>, <italic>entB</italic> and <italic>wzi</italic> and 190 showed positive <italic>fimH</italic>, <italic>mrkD</italic>, <italic>entB</italic>, <italic>irp2</italic> and <italic>wzi</italic>, which were the two primary modes. A total of 94, 165 and 29 strains were denoted as hypervirulent <italic>K. pneumoniae</italic> (HvKP), <italic>bla</italic><sub>KPC</sub>(+)-KP and Hv-<italic>bla</italic><sub>KPC</sub>(+)-KP. ST11 accounted for 17 among the 29 Hv-<italic>bla</italic><sub>KPC</sub>(+)-KP strains; Genes <italic>iucA</italic>, <italic>p-rmpA2</italic> and <italic>p-rmpA</italic> were positive in 28, 26 and 18 Hv-<italic>bla</italic><sub>KPC</sub>(+)-KP strains respectively. Among the 29 Hv-<italic>bla</italic><sub>KPC</sub>(+)-KP strains exhibiting four super clusters from GenBank, IncHI1B plasmids carrying virulence genes and IncFII ones with <italic>bla</italic><sub>KPC</sub> were responsible for both 23 strains respectively.</p></sec><sec><title>Conclusions</title><p>Positive rates of virulence genes vary remarkably in <italic>K. pneumoniae</italic>. Genes <italic>iucA</italic>, <italic>p-rmpA2</italic> and <italic>p-rmpA</italic> were primary ones inducing Hv-<italic>bla</italic><sub>KPC</sub>(+)-KP. IncHI1B plasmids carrying virulence genes and IncFII ones with <italic>bla</italic><sub>KPC</sub> constitute the primary combination responsible for Hv-<italic>bla</italic><sub>KPC</sub>(+)-KP. The making of Hv-<italic>bla</italic><sub>KPC</sub>(+)-KP is mostly <italic>via bla</italic><sub>KPC</sub>(+)-KP acquiring another plasmid harboring virulence genes.</p></sec>