Limits...
Identification and characterization of the chromosomal yefM-yoeB toxin-antitoxin system of Streptococcus suis.

Zheng C, Xu J, Ren S, Li J, Xia M, Chen H, Bei W - Sci Rep (2015)

Bottom Line: Overproduction of S. suis YoeB toxin inhibited the growth of E. coli, and the toxicity of S. suis YoeB could be alleviated by the antitoxin YefM from S. suis and Streptococcus pneumoniae, but not by E. coli YefM.In a murine infection model, deletion of the yefM-yoeB locus had no effect on the virulence of S. suis serotype 2.Collectively, our data suggested that the yefM-yoeB locus of S. suis is an active TA system without the involvement of virulence.

View Article: PubMed Central - PubMed

Affiliation: 1] State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, 430070, China [2] Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.

ABSTRACT
Toxin-antitoxin (TA) systems are widely prevalent in the genomes of bacteria and archaea. These modules have been identified in Escherichia coli and various other bacteria. However, their presence in the genome of Streptococcus suis, an important zoonotic pathogen, has received little attention. In this study, we describe the identification and characterization of a type II TA system, comprising the chromosomal yefM-yoeB locus of S. suis. The yefM-yoeB locus is present in the genome of most serotypes of S. suis. Overproduction of S. suis YoeB toxin inhibited the growth of E. coli, and the toxicity of S. suis YoeB could be alleviated by the antitoxin YefM from S. suis and Streptococcus pneumoniae, but not by E. coli YefM. More importantly, introduction of the S. suis yefM-yoeB system into E. coli could affect cell growth. In a murine infection model, deletion of the yefM-yoeB locus had no effect on the virulence of S. suis serotype 2. Collectively, our data suggested that the yefM-yoeB locus of S. suis is an active TA system without the involvement of virulence.

No MeSH data available.


Related in: MedlinePlus

Effect of induction of YoeB, YefM or YefM-YoeB on growth of E. coli.Overnight cultures of E. coli Top10 cells harbouring the plasmid pBADhisA-yefM, pBADhisA-yoeB, pBADhisA-yefM-yoeB and pBADhisA were diluted 1:1000 in LB-ampicillin. Each culture was then divided into two equal volumes. The first half served as the control, to which 0.2% D-glucose was added (a), 0.2% L-arabinose was added to the second half to induce expression of the target gene (b). Culture growth was evaluated by measuring the OD600 every hour. The data shown are averages with standard deviations for the results from three independent experiments.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4536659&req=5

f3: Effect of induction of YoeB, YefM or YefM-YoeB on growth of E. coli.Overnight cultures of E. coli Top10 cells harbouring the plasmid pBADhisA-yefM, pBADhisA-yoeB, pBADhisA-yefM-yoeB and pBADhisA were diluted 1:1000 in LB-ampicillin. Each culture was then divided into two equal volumes. The first half served as the control, to which 0.2% D-glucose was added (a), 0.2% L-arabinose was added to the second half to induce expression of the target gene (b). Culture growth was evaluated by measuring the OD600 every hour. The data shown are averages with standard deviations for the results from three independent experiments.

Mentions: To determine whether the yefM-yoeB locus is indeed an active TA system, the yefM and yoeB genes were cloned separately as well as together into the pBADhisA expression vector. The plasmids were introduced into E. coli Top10 cells, and the transformants were selected in LB agar plates with 0.2% D-glucose (repressed conditions of PBAD). E. coli Top10 cells harbouring the corresponding plasmids were grown in LB medium, and 0.2% D-glucose or L-arabinose was added at time zero. In the presence of 0.2% D-glucose, Top10 cells harbouring the pBADhisA-yefM and pBADhisA plasmids showed no major difference in growth, while cells carrying the pBADhisA-yoeB plasmid showed a moderate growth defect (Fig. 3a). In the case of inductive conditions (0.2% L-arabinose), E. coli Top10 cells harbouring the pBADhisA-yoeB plasmid exhibited drastic growth inhibition, while cells harbouring other two plasmids showed only moderate reductions in their OD600 value (Fig. 3b). Surprisingly, under both repressed and inductive conditions, E. coli Top10 cells harbouring the pBADhisA-yefM-yoeB plasmid exhibited obvious growth inhibition (Fig. 3), Even so, Top10 cells carrying the pBADhisA-yefM-yoeB plasmid showed much better growth than that carrying pBADhisA-yoeB (Fig. 3b), indicating that YoeB-induced growth inhibition could be alleviated by YefM.


Identification and characterization of the chromosomal yefM-yoeB toxin-antitoxin system of Streptococcus suis.

Zheng C, Xu J, Ren S, Li J, Xia M, Chen H, Bei W - Sci Rep (2015)

Effect of induction of YoeB, YefM or YefM-YoeB on growth of E. coli.Overnight cultures of E. coli Top10 cells harbouring the plasmid pBADhisA-yefM, pBADhisA-yoeB, pBADhisA-yefM-yoeB and pBADhisA were diluted 1:1000 in LB-ampicillin. Each culture was then divided into two equal volumes. The first half served as the control, to which 0.2% D-glucose was added (a), 0.2% L-arabinose was added to the second half to induce expression of the target gene (b). Culture growth was evaluated by measuring the OD600 every hour. The data shown are averages with standard deviations for the results from three independent experiments.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4536659&req=5

f3: Effect of induction of YoeB, YefM or YefM-YoeB on growth of E. coli.Overnight cultures of E. coli Top10 cells harbouring the plasmid pBADhisA-yefM, pBADhisA-yoeB, pBADhisA-yefM-yoeB and pBADhisA were diluted 1:1000 in LB-ampicillin. Each culture was then divided into two equal volumes. The first half served as the control, to which 0.2% D-glucose was added (a), 0.2% L-arabinose was added to the second half to induce expression of the target gene (b). Culture growth was evaluated by measuring the OD600 every hour. The data shown are averages with standard deviations for the results from three independent experiments.
Mentions: To determine whether the yefM-yoeB locus is indeed an active TA system, the yefM and yoeB genes were cloned separately as well as together into the pBADhisA expression vector. The plasmids were introduced into E. coli Top10 cells, and the transformants were selected in LB agar plates with 0.2% D-glucose (repressed conditions of PBAD). E. coli Top10 cells harbouring the corresponding plasmids were grown in LB medium, and 0.2% D-glucose or L-arabinose was added at time zero. In the presence of 0.2% D-glucose, Top10 cells harbouring the pBADhisA-yefM and pBADhisA plasmids showed no major difference in growth, while cells carrying the pBADhisA-yoeB plasmid showed a moderate growth defect (Fig. 3a). In the case of inductive conditions (0.2% L-arabinose), E. coli Top10 cells harbouring the pBADhisA-yoeB plasmid exhibited drastic growth inhibition, while cells harbouring other two plasmids showed only moderate reductions in their OD600 value (Fig. 3b). Surprisingly, under both repressed and inductive conditions, E. coli Top10 cells harbouring the pBADhisA-yefM-yoeB plasmid exhibited obvious growth inhibition (Fig. 3), Even so, Top10 cells carrying the pBADhisA-yefM-yoeB plasmid showed much better growth than that carrying pBADhisA-yoeB (Fig. 3b), indicating that YoeB-induced growth inhibition could be alleviated by YefM.

Bottom Line: Overproduction of S. suis YoeB toxin inhibited the growth of E. coli, and the toxicity of S. suis YoeB could be alleviated by the antitoxin YefM from S. suis and Streptococcus pneumoniae, but not by E. coli YefM.In a murine infection model, deletion of the yefM-yoeB locus had no effect on the virulence of S. suis serotype 2.Collectively, our data suggested that the yefM-yoeB locus of S. suis is an active TA system without the involvement of virulence.

View Article: PubMed Central - PubMed

Affiliation: 1] State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, 430070, China [2] Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.

ABSTRACT
Toxin-antitoxin (TA) systems are widely prevalent in the genomes of bacteria and archaea. These modules have been identified in Escherichia coli and various other bacteria. However, their presence in the genome of Streptococcus suis, an important zoonotic pathogen, has received little attention. In this study, we describe the identification and characterization of a type II TA system, comprising the chromosomal yefM-yoeB locus of S. suis. The yefM-yoeB locus is present in the genome of most serotypes of S. suis. Overproduction of S. suis YoeB toxin inhibited the growth of E. coli, and the toxicity of S. suis YoeB could be alleviated by the antitoxin YefM from S. suis and Streptococcus pneumoniae, but not by E. coli YefM. More importantly, introduction of the S. suis yefM-yoeB system into E. coli could affect cell growth. In a murine infection model, deletion of the yefM-yoeB locus had no effect on the virulence of S. suis serotype 2. Collectively, our data suggested that the yefM-yoeB locus of S. suis is an active TA system without the involvement of virulence.

No MeSH data available.


Related in: MedlinePlus