The Streptococcus suis transcriptional landscape reveals adaptation mechanisms in pig blood and cerebrospinal fluid.
Streptococcus suis (SS) is an important pathogen of pigs, and it is also recognized as a zoonotic agent for humans. SS infection may result in septicemia or meningitis in the host. However, little is known about genes that contribute to the virulence process and survival within host blood or cerebrospinal fluid (CSF). Small RNAs (sRNA) have emerged as key regulators of virulence in several bacteria, but they have not been investigated in SS. Here, using a differential RNA-sequencing approach and RNAs from SS strain P1/7 grown in rich medium, pig blood, or CSF, we present the SS genome-wide map of 793 transcriptional start sites and 370 operons. In addition to identifying 29 sRNAs, we show that five sRNA deletion mutants attenuate SS virulence in a zebrafish infection model. Homology searches revealed that 10 sRNAs were predicted to be present in other pathogenic Streptococcus species. Compared with wild-type strain P1/7, sRNAs rss03, rss05, and rss06 deletion mutants were significantly more sensitive to killing by pig blood. It is possible that rss06 contributes to SS virulence by indirectly activating expression of SSU0308, a virulence gene encoding a zinc-binding lipoprotein. In blood, genes involved in the synthesis of capsular polysaccharide (CPS) and subversion of host defenses were up-regulated. In contrast, in CSF, genes for CPS synthesis were down-regulated. Our study is the first analysis of SS sRNAs involved in virulence and has both improved our understanding of SS pathogenesis and increased the number of sRNAs known to play definitive roles in bacterial virulence.
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China OIE Reference Laboratory for Swine Streptococcosis, Nanjing 210095, China.
Zongfu
Z
Wu
BGI-Shenzhen, Shenzhen 518083, China.
Chunyan
C
Wu
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China OIE Reference Laboratory for Swine Streptococcosis, Nanjing 210095, China.
Jing
J
Shao
BGI-Shenzhen, Shenzhen 518083, China.
Zhenzhen
Z
Zhu
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China OIE Reference Laboratory for Swine Streptococcosis, Nanjing 210095, China.
Weixue
W
Wang
BGI-Shenzhen, Shenzhen 518083, China.
Wenwei
W
Zhang
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China OIE Reference Laboratory for Swine Streptococcosis, Nanjing 210095, China.
Min
M
Tang
BGI-Shenzhen, Shenzhen 518083, China.
Na
N
Pei
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China OIE Reference Laboratory for Swine Streptococcosis, Nanjing 210095, China Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China.
Hongjie
H
Fan
BGI-Shenzhen, Shenzhen 518083, China.
Jiguang
J
Li
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China OIE Reference Laboratory for Swine Streptococcosis, Nanjing 210095, China.
Huochun
H
Yao
Jiangsu Engineering Research Center for microRNA Biology and Biotechnology, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210093, China.
Hongwei
H
Gu
BGI-Shenzhen, Shenzhen 518083, China.
Xun
X
Xu
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China OIE Reference Laboratory for Swine Streptococcosis, Nanjing 210095, China.
Chengping
C
Lu
D000818:Animals; D001769:Blood / Q000382:microbiology*; D002555:Cerebrospinal Fluid / Q000382:microbiology*; D055106:Genome-Wide Association Study / Q000379:methods; D009876:Operon / Q000235:genetics; D012329:RNA, Bacterial / Q000235:genetics*; D017384:Sequence Deletion / Q000235:genetics; D013290:Streptococcal Infections / Q000235:genetics* / Q000382:microbiology; D017011:Streptococcus suis / Q000235:genetics*; D013552:Swine; D014158:Transcription, Genetic / Q000235:genetics*; D015854:Up-Regulation / Q000235:genetics; D014774:Virulence / Q000235:genetics*; D015027:Zebrafish / Q000235:genetics / Q000382:microbiology
D012329:RNA, Bacterial
Streptococcus suis; TSS map; differential RNA-seq; small RNAs; virulence