AUTHOR=Tian Chongmei , Song Jianqin , Ren Lingzhi , Huang Delian , Wang Siwei , Fu Liping , Zhao Yaping , Bai Yongfeng , Fan Xueyu , Ma Tianhong , Ying Junjie 

TITLE=Complete genetic characterization of carbapenem-resistant Acinetobacter johnsonii, co-producing NDM-1, OXA-58, and PER-1 in a patient source

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=13

YEAR=2023

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2023.1227063

DOI=10.3389/fcimb.2023.1227063

ISSN=2235-2988

ABSTRACT=<p>The emergence of carbapenemase-producing <italic>Acinetobacter</italic> spp. has been widely reported and become a global threat. However, carbapenem-resistant <italic>A. johnsonii</italic> strains are relatively rare and without comprehensive genetic structure analysis, especially for isolates collected from human specimen. Here, one <italic>A. johnsonii</italic> AYTCM strain, co-producing NDM-1, OXA-58, and PER-1 enzymes, was isolated from sputum in China in 2018. Antimicrobial susceptibility testing showed that it was resistant to meropenem, imipenem, ceftazidime, ciprofloxacin, and cefoperazone/sulbactam. Whole-genome sequencing and bioinformatic analysis revealed that it possessed 11 plasmids. <italic>bla</italic><sub>OXA-58</sub> and <italic>bla</italic><sub>PER-1</sub> genes were located in the pAYTCM-1 plasmid. Especially, a complex class 1 integron consisted of a 5′ conserved segment (5′ CS) and 3′ CS, which was found to carry sul1, arr-3, qnrVC6<italic>, and bla</italic><sub>PER-1</sub> cassettes. Moreover, the <italic>bla</italic><sub>NDM-1</sub> gene was located in 41,087 conjugative plasmids and was quite stable even after 70 passages under antibiotics-free conditions. In addition, six prophage regions were identified. Tracking of closely related plasmids in the public database showed that pAYTCM-1 was similar to pXBB1-9, pOXA23_010062, pOXA58_010030, and pAcsw19-2 plasmids, which were collected from the strains of sewage in China. Concerning the pAYTCM-3 plasmids, results showed that strains were collected from different sources and their hosts were isolated from various countries, such as China, USA, Japan, Brazil, and Mexico, suggesting that a wide spread occurred all over the world. In conclusion, early surveillance is warranted to avoid the extensive spread of this high-risk clone in the healthcare setting.</p>