Identification of Three Type II Toxin-Antitoxin Systems in <i>Streptococcus suis</i> Serotype 2
Jiali Xu,
Nian Zhang,
Manman Cao,
Sujing Ren,
Ting Zeng,
Minglu Qin,
Xigong Zhao,
Fangyan Yuan,
Huanchun Chen,
Weicheng Bei
Affiliations
Jiali Xu
State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
Nian Zhang
State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
Manman Cao
State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
Sujing Ren
State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
Ting Zeng
State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
Minglu Qin
State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
Xigong Zhao
State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
Fangyan Yuan
Key Laboratory of Prevention and Control Agents for Animal Bacteriosis, Institute of Animal Husbandry and Veterinary Sciences, Hubei Academy of Agricultural Sciences, Wuhan 430064, China
Huanchun Chen
State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
Weicheng Bei
State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
Type II toxin-antitoxin (TA) systems are highly prevalent in bacterial genomes and have been extensively studied. These modules involve in the formation of persistence cells, the biofilm formation, and stress resistance, which might play key roles in pathogen virulence. SezAT and yefM-yoeB TA modules in Streptococcus suis serotype 2 (S. suis 2) have been studied, although the other TA systems have not been identified. In this study, we investigated nine putative type II TA systems in the genome of S. suis 2 strain SC84 by bioinformatics analysis and identified three of them (two relBE loci and one parDE locus) that function as typical type II TA systems. Interestingly, we found that the introduction of the two RelBE TA systems into Escherichia coli or the induction of the ParE toxin led to cell filamentation. Promoter activity assays indicated that RelB1, RelB2, ParD, and ParDE negatively autoregulated the transcriptions of their respective TA operons, while RelBE2 positively autoregulated its TA operon transcription. Collectively, we identified three TA systems in S. suis 2, and our findings have laid an important foundation for further functional studies on these TA systems.
