Expanding of ST11 Carbapenemase-Producing Klebsiella pneumoniae Subclones in a Chinese Hospital, Shenzhen, China

Min Zhang,1,2 Jia Li,3 Yuemei Lu,4 Weiyuan Wu,4 Jinsong Wu,4 Yanji Xu,1,5 Yuxin Zhong,1,2 Shiyi Liu,1,2 Chuchu Lin,6 Shuye Xu,3 Dandan Chen,1,2 Xuefeng Gao,7 Yutian Luo,8 Huaisheng Chen,8 Xueyan Liu,8 Wei Huang1,2 1Shenzhen People’s Hospital, Shenzhen Institute of Respiratory Diseases, Shenzhen, Guangdong, People’s Republic of China; 2Bacteriology & Antibacterial Resistance Surveillance Laboratory, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, People’s Republic of China; 3Department of Nosocomial Infection Control, Bengbu Third People’s Hospital, Bengbu, People’s Republic of China; 4Department of Clinical Microbiology, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, People’s Republic of China; 5Nanshan District Center of Chronic Disease Control, Shenzhen, People’s Republic of China; 6Department of Nosocomial Infection Control, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, People’s Republic of China; 7Department of Gastroenterology and Hepatology, Shenzhen University General Hospital, Shenzhen, People’s Republic of China; 8Department of Intensive Care Unit, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, People’s Republic of ChinaCorrespondence: Wei HuangBacteriology & Antibacterial Resistance Surveillance Laboratory, Shenzhen Institute of Respiratory Diseases, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University The First Affiliated Hospital, Southern University of Science and Technology), No. 1017 Dongmen North Road, Shenzhen People’s Hospital, Shenzhen, 518020, Guangdong, People’s Republic of ChinaTel +86 7522942513Fax +86 7522942514Email whuang_sz@163.comBackground: ST11 is the most prevalent sequence type of clinical Klebsiella pneumoniae in China.Methods: We investigated the characteristics of the ST11 subclones using core genome multi-locus sequence typing (cgMLST). Ninety-three carbapenemase-producing K. pneumoniae isolates were collected at Shenzhen People’s Hospital. Then, whole-genome sequencing and cgMLST were used to discriminate apparent subclones within the ST11 group.Results: We analyzed the prevalence and genetic relationships of these subclones. ST11 and K. pneumoniae carbapenemase (KPC-2) were the predominant genotype and carbapenemase, respectively, in the clinical carbapenemase-producing K. pneumoniae strains. cgMLST scheme genotyping divided the ST11 group into two clades across seven complex types (CTs). CT1313 was the most prevalent subclone. The deletion of galF and a high frequency of SNPs in genes associated with the stress- and SOS-responses were found in CT1291 and CT2405 over time, respectively.Conclusion: Our results indicated that the subclones of the ST11 group had different patterns of prevalence. Highly discriminatory genotyping techniques, such as cgMLST scheme, should be used in further molecular epidemiology investigations.Keywords: Klebsiella pneumoniae, whole genome sequencing, cgMLST, ST11, carbapenem-resistance