AUTHOR=Sun Hua-Run , Cui Xiao-Die , Liu Xiao-Kang , Li Shuai-Hua , Yi Kai-Fang , Pan Yu-Shan , Wu Hua , Yuan Li , Hu Gong-Zheng , He Dan-Dan 

TITLE=Molecular Characterization of a Novel Integrative Conjugative Element ICEHpa1 in Haemophilus parasuis

JOURNAL=Frontiers in Microbiology

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2020.01884

DOI=10.3389/fmicb.2020.01884

ISSN=1664-302X

ABSTRACT=<p>ICE<italic>Hpa1</italic> was identified in the genome of a serovar 8 <italic>Haemophilus parasuis</italic> ST288 isolate YHP170504 from a case of swine lower respiratory tract infection. The aim of the present study was to characterize the integrative conjugative element ICE<italic>Hpa1</italic> and its multiresistance region. Susceptibility testing was determined by broth microdilution and the complete ICE<italic>Hpa1</italic> was identified by WGS analysis. The full sequence of ICE<italic>Hpa1</italic> was analyzed with bioinformatic tools. The presence of ICE<italic>Hpa1</italic>, its circular intermediate and integration site were confirmed by PCR and sequence analysis. Transfer of ICE<italic>Hpa1</italic> was confirmed by conjugation. ICE<italic>Hpa1</italic> has a size of 68,922 bp with 37.42% GC content and harbors 81 genes responsible for replication and stabilization, transfer, integration, and accessory functions, as well as seven different resistance genes [<italic>bla</italic><sub>Rob–</sub><sub>3</sub>, <italic>tet</italic>(B), <italic>aphA1</italic>, <italic>strA</italic>, <italic>strB</italic>, <italic>aac(6)′-Ie-aph(2′)-Ia</italic>, and <italic>sul2</italic>]. Conjugation experiments showed that ICE<italic>Hpa1</italic> could be transferred to <italic>H. parasuis</italic> V43 with frequencies of 6.1 × 10<sup>–6</sup>. This is the first time a multidrug-resistance ICE has been reported in <italic>H. parasuis</italic>. Seven different resistance genes were located on a novel integrative conjugative element ICE<italic>Hpa1</italic>, which suggests that the ICE<italic>Hpa1</italic> is capable of acquiring foreign genes and serving as a carrier for various resistance genes.</p>