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

Construction and confirmation of the mutant and complementation strains.(a) Diagram of genetic organization of the WT and ΔyefM-yoeB strains. (b) PCR confirmation of the mutant and complementation strains. The primer pairs used in the PCR analysis are indicated above the lanes. Templates were genomic DNAs from the WT strain (lanes 1 and 5), ΔyefM-yoeB (lanes 2 and 6), CΔyefM-yoeB (lanes 3 and 7), and H2O (lanes 4 and 8). (c) RT-PCR analysis of yefM-yoeB transcripts. Total RNAs were extracted from the WT strain (lane 1), ΔyefM-yoeB (lanes 2), and CΔyefM-yoeB (lane 3). cDNA generated from these RNA samples was subjected to RT-PCR analysis with primer pair ATin1/ATin2. The products were analysed by electrophoresis (lanes 4, the WT strain; lanes 5, ΔyefM-yoeB; lanes 6, CΔyefM-yoeB). The DL 2000 DNA Marker is shown on the left (lane M).
© Copyright Policy - open-access
Related In: Results  -  Collection

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

f6: Construction and confirmation of the mutant and complementation strains.(a) Diagram of genetic organization of the WT and ΔyefM-yoeB strains. (b) PCR confirmation of the mutant and complementation strains. The primer pairs used in the PCR analysis are indicated above the lanes. Templates were genomic DNAs from the WT strain (lanes 1 and 5), ΔyefM-yoeB (lanes 2 and 6), CΔyefM-yoeB (lanes 3 and 7), and H2O (lanes 4 and 8). (c) RT-PCR analysis of yefM-yoeB transcripts. Total RNAs were extracted from the WT strain (lane 1), ΔyefM-yoeB (lanes 2), and CΔyefM-yoeB (lane 3). cDNA generated from these RNA samples was subjected to RT-PCR analysis with primer pair ATin1/ATin2. The products were analysed by electrophoresis (lanes 4, the WT strain; lanes 5, ΔyefM-yoeB; lanes 6, CΔyefM-yoeB). The DL 2000 DNA Marker is shown on the left (lane M).

Mentions: To investigate the functions of the yefM-yoeB locus in S. suis 2, an isogenic yefM-yoeB knockout mutant of S. suis 2 strain SC19, termed ΔyefM-yoeB, was constructed through homologous recombination (Fig. 6a). To rule out the possible polar effect and introduction of a second mutation during the construction of ΔyefM-yoeB, we generated a complementation strain, designated CΔyefM-yoeB using the E. coli-S. suis shuttle vector pSET241. The resulting mutant and complementation strains were confirmed by PCR (Fig. 6b), RT-PCR (Fig. 6c) and direct DNA sequencing (data not shown).


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)

Construction and confirmation of the mutant and complementation strains.(a) Diagram of genetic organization of the WT and ΔyefM-yoeB strains. (b) PCR confirmation of the mutant and complementation strains. The primer pairs used in the PCR analysis are indicated above the lanes. Templates were genomic DNAs from the WT strain (lanes 1 and 5), ΔyefM-yoeB (lanes 2 and 6), CΔyefM-yoeB (lanes 3 and 7), and H2O (lanes 4 and 8). (c) RT-PCR analysis of yefM-yoeB transcripts. Total RNAs were extracted from the WT strain (lane 1), ΔyefM-yoeB (lanes 2), and CΔyefM-yoeB (lane 3). cDNA generated from these RNA samples was subjected to RT-PCR analysis with primer pair ATin1/ATin2. The products were analysed by electrophoresis (lanes 4, the WT strain; lanes 5, ΔyefM-yoeB; lanes 6, CΔyefM-yoeB). The DL 2000 DNA Marker is shown on the left (lane M).
© Copyright Policy - open-access
Related In: Results  -  Collection

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

f6: Construction and confirmation of the mutant and complementation strains.(a) Diagram of genetic organization of the WT and ΔyefM-yoeB strains. (b) PCR confirmation of the mutant and complementation strains. The primer pairs used in the PCR analysis are indicated above the lanes. Templates were genomic DNAs from the WT strain (lanes 1 and 5), ΔyefM-yoeB (lanes 2 and 6), CΔyefM-yoeB (lanes 3 and 7), and H2O (lanes 4 and 8). (c) RT-PCR analysis of yefM-yoeB transcripts. Total RNAs were extracted from the WT strain (lane 1), ΔyefM-yoeB (lanes 2), and CΔyefM-yoeB (lane 3). cDNA generated from these RNA samples was subjected to RT-PCR analysis with primer pair ATin1/ATin2. The products were analysed by electrophoresis (lanes 4, the WT strain; lanes 5, ΔyefM-yoeB; lanes 6, CΔyefM-yoeB). The DL 2000 DNA Marker is shown on the left (lane M).
Mentions: To investigate the functions of the yefM-yoeB locus in S. suis 2, an isogenic yefM-yoeB knockout mutant of S. suis 2 strain SC19, termed ΔyefM-yoeB, was constructed through homologous recombination (Fig. 6a). To rule out the possible polar effect and introduction of a second mutation during the construction of ΔyefM-yoeB, we generated a complementation strain, designated CΔyefM-yoeB using the E. coli-S. suis shuttle vector pSET241. The resulting mutant and complementation strains were confirmed by PCR (Fig. 6b), RT-PCR (Fig. 6c) and direct DNA sequencing (data not shown).

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