Effect of kpsM on the virulence of porcine extraintestinal pathogenic Escherichia coli

Bingbing Zong; Wugang Liu; Yanyan Zhang; Xiangru Wang; Huanchun Chen; Chen Tan

doi:10.1093/femsle/fnw232

Effect of kpsM on the virulence of porcine extraintestinal pathogenic Escherichia coli

FEMS Microbiol Lett. 2016 Nov 1;363(21):fnw232. doi: 10.1093/femsle/fnw232.

Authors

Bingbing Zong^{1

2

3}, Wugang Liu^{1

2

3}, Yanyan Zhang^{1

2

3}, Xiangru Wang^{1

2

3}, Huanchun Chen^{1

2

3}, Chen Tan^{1

2

3}

Affiliations

¹ State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China.
² The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, Hubei, China.
³ Key Laboratory of development of veterinary diagnostic products of Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, Hubei, China.

PMID: 27737948
DOI: 10.1093/femsle/fnw232

Abstract

In recent years, extraintestinal pathogenic Escherichia coli (ExPEC) has been found to pose a great threat to human and animal health, but its pathogenic mechanism is not fully understood yet. Capsular polysaccharide, an essential virulence factor in these bacteria, can damage the host immune system, and kpsM is a member of the gene cluster responsible for capsular polysaccharide synthesis. In this study, whole sequence alignment of the virulent strain PCN033 and the attenuated strain PCN061 revealed that kpsM exists in PCN033 but not in PCN061. To determine its function and biological characteristics, we deleted kpsM from PCN033 by homologous recombination. The results of adhesion assays, phagocytosis assays and serum bactericidal assays together with the results of colonization assays in mice indicate that the deletion of kpsM decreases the virulence of porcine ExPEC. Our findings about the biological characteristics of kpsM help to elucidate the complex pathogenic mechanism of ExPEC.

Keywords: kpsM; ExPEC; biological characteristics; capsular polysaccharide; gene deletion; virulence.