Isolation and identification of a bacteriophage capable of infecting Streptococcus suis type 2 strains

Ma, Ye; Chen, Lu

doi:10.1016/j.vetmic.2008.05.013

Cited by 37 publications

(33 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Lysin, encoded by most double-stranded DNA (dsDNA) bacteriophages, is essential for bacterial host cell lysis. Phage SMP has been identified as a dsDNA phage (23), and its putative lysin, designated LySMP, was expressed and purified as previously described, with some modification (35). Briefly, E. coli BL21 harboring the plasmid pET-lys, coding for LySMP, was inoculated into LB containing 50 g/ml kanamycin and grown at 27°C with vigorous shaking, followed by 0.5 mM isopropyl-␤-D-thiogalactopyranoside (IPTG) induction for 4 h when the OD 600 reached 0.5.…”

Section: Methodsmentioning

confidence: 99%

mentioning

confidence: 99%

“…Phage SMP is an S. suis serotype 2 lytic bacteriophage isolated from nasal swabs of healthy Bama minipigs (23). Although SMP can lyse planktonic S. suis cultures efficiently (23), its efficacy against S. suis biofilms is unknown. Bacteriophage-encoded lysins (cell wall hydrolases) are important for the release of lytic phages from the infected bacterial host cell (35).…”

mentioning

confidence: 99%

See 2 more Smart Citations

Application of a Bacteriophage Lysin To Disrupt Biofilms Formed by the Animal Pathogen Streptococcus suis

Meng

Shi

et al. 2011

Appl Environ Microbiol

View full text Add to dashboard Cite

Bacterial biofilms are crucial to the pathogenesis of many important infections and are difficult to eradicate. Streptococcus suis is an important pathogen of pigs, and here the biofilm-forming ability of 32 strains of this species was determined. Significant biofilms were completely formed by 10 of the strains after 60 h of incubation, with exopolysaccharide production in the biofilm significantly higher than that in the corresponding planktonic cultures. S. suis strain SS2-4 formed a dense biofilm, as revealed by scanning electron microscopy, and in this state exhibited increased resistance to a number of antibiotics (ampicillin, amoxicillin, ciprofloxacin, kanamycin, and rifampin) compared to that of planktonic cultures. A bacteriophage lysin, designated LySMP, was used to attack biofilms alone and in combination with antibiotics and bacteriophage. The results demonstrated that the biofilms formed by S. suis, especially strains SS2-4 and SS2-H, could be dispersed by LySMP and with >80% removal compared to a biofilm reduction by treatment with either antibiotics or bacteriophage alone of less than 20%; in addition to disruption of the biofilm structure, the S. suis cells themselves were inactivated by LySMP. The efficacy of LySMP was not dose dependent, and in combination with antibiotics, it acted synergistically to maximize dispersal of the S. suis biofilm and inactivate the released cells. These data suggest that bacteriophage lysin could form part of an effective strategy to treat S. suis infections and represents a new class of antibiofilm agents.

show abstract

Section: Methodsmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Application of a Bacteriophage Lysin To Disrupt Biofilms Formed by the Animal Pathogen Streptococcus suis

Meng

Shi

et al. 2011

Appl Environ Microbiol

View full text Add to dashboard Cite

show abstract

“…⌽SsUD.1 appears to be a novel genetic element. In S. suis, no resistance genes have previously been detected in sequenced phage genomes (16,21). The chromosome integration of ⌽SsUD.1 into the S. suis rum gene, at the same site where ⌽m46.1 is integrated into the S. pyogenes rum gene, suggests that this site, known to be an insertional hot spot for mobile elements in S. pyogenes (4,6), may play a similar role in S. suis.…”

Section: Vol 55 2011 Tet(w)-carrying Genetic Elements In Human S Smentioning

confidence: 99%

Different Genetic Elements Carrying the tet (W) Gene in Two Human Clinical Isolates of Streptococcus suis

Palmieri

Princivalli

Brenciani

et al. 2011

Antimicrob Agents Chemother

View full text Add to dashboard Cite

The genetic support for tet(W), an emerging tetracycline resistance determinant, was studied in two strains of Streptococcus suis, SsCA and SsUD, both isolated in Italy from patients with meningitis. Two completely different tet(W)-carrying genetic elements, sharing only a tet(W)-containing segment barely larger than the gene, were found in the two strains. The one from strain SsCA was nontransferable, and aside from an erm(B)-containing insertion, it closely resembled a genomic island recently described in an S. suis Chinese human isolate in sequence, organization, and chromosomal location. The tet(W)-carrying genetic element from strain SsUD was transferable (at a low frequency) and, though apparently noninducible following mitomycin C treatment, displayed a typical phage organization and was named ⌽SsUD.1. Its full sequence was determined (60,711 bp), the highest BLASTN score being Streptococcus pyogenes ⌽m46.1. ⌽SsUD.1 exhibited a unique combination of antibiotic and heavy metal resistance genes. Besides tet(W), it contained a MAS (macrolide-aminoglycoside-streptothricin) fragment with an erm(B) gene having a deleted leader peptide and a cadC/cadA cadmium efflux cassette. The MAS fragment closely resembled the one recently described in pneumococcal transposons Tn6003 and Tn1545. These resistance genes found in the ⌽SsUD.1 phage scaffold differed from, but were in the same position as, cargo genes carried by other streptococcal phages. The chromosome integration site of ⌽SsUD.1 was at the 3 end of a conserved tRNA uracil methyltransferase (rum) gene. This site, known to be an insertional hot spot for mobile elements in S. pyogenes, might play a similar role in S. suis. tet(W)is an emerging tetracycline resistance determinant whose host range, including Gram-positive, Gram-negative, aerobic, and anaerobic bacteria, is second only to that of tet(M) among ribosomal protection tet genes (26). tet(W) was first identified in the rumen anaerobe Butyrivibrio fibrisolvens (3), where it was associated with a transposable chromosomal element. It was subsequently detected in several other bacteria of the animal and human gastrointestinal tract, associated with either conjugative or nonconjugative elements (1, 5, 13, 14, 19, 29-31, 33, 37).In 2008 we first described tet(W) in Streptococcus suis, in a human isolate from a sporadic case of meningitis in Italy (23). S. suis, a major swine pathogen worldwide, is emerging as a zoonotic agent, the most common human clinical manifestations being meningitis and sepsis (20,39). Most cases of human S. suis infection have originated in Southeast Asia, where pig rearing is widespread, and large outbreaks have occurred in China (20). In industrialized countries human infections are rare, albeit probably underdiagnosed, and usually arise as sporadic cases. The growing interest in this emerging pathogen is reflected by recent whole-genome sequencing studies of selected isolates directed at elucidating the occurrence and evolution of the genetic determinants of its pathogenicity and dru...

show abstract

“…S. suis lytic phages are difficult to isolate. Until now, only one S. suis lytic phage, SMP, was reported (23,37). Thus, phage lysins were expected to prevent S. suis infections.…”

Section: Discussionmentioning

confidence: 99%

Prophage Lysin Ply30 Protects Mice from Streptococcus suis and Streptococcus equi subsp. zooepidemicus Infections

Tang

Wang

et al. 2015

Appl Environ Microbiol

View full text Add to dashboard Cite

Streptococcus suis and Streptococcus equi subsp. zooepidemicus are capable of infecting humans and various animals, causing significant problems for the worldwide swine industry. As antibiotic resistance has increased, lysosomal enzymes encoded by phages have shown potential for use against pathogenic bacteria. In this study, a novel bacteriophage lysin, Ply30, encoded by the S. suis prophage phi30c, was recombinantly expressed and purified. Ply30 showed high bacteriolysis activity on S. suis and S. equi subsp. zooepidemicus in vitro. The ratio of the optical density at 600 nm (OD 600 ) with treatment versus the OD 600 with no treatment for most tested S. suis and S. equi subsp. zooepidemicus strains decreased from 1 to <0.3 and <0.5, respectively, within 1 h. The results of plate viability assays showed that treated bacteria suffered a 1-to 2-log decrease in CFU within 1 h. The optimal concentration of Ply30 was 50 g/ml, and the optimal pH was 7. Moreover, Ply30 maintained high activity over a wide pH range (pH 6 to 10). The MICs of Ply30 against Streptococcus strains ranged from 16 to 512 g/ml. In vivo, a 2-mg dose of Ply30 protected 90% (9/10 mice) of mice from infection with S. equi subsp. zooepidemicus and 80% (8/10 mice) of mice from infection with S. suis. Seven days after lysin Ply30 treatment, bacterial loads were significantly decreased in all tested organs and blood compared with those at 1 h postinfection without Ply30 treatment. Ply30 showed in vitro and in vivo antimicrobial efficiency and protected mice against two kinds of bacterial infections, indicating that Ply30 may be an effective therapeutic against streptococci. Streptococcus suis and Streptococcus equi subsp. zooepidemicus are emerging zoonotic, pathogenic, Gram-positive bacteria capable of infecting humans and various animals, such as horses, pigs, ruminants, guinea pigs, monkeys, cats, and dogs (1-3). S. suis can cause septicemia, arthritis, and meningitis in pigs (4). Liu et al. identified 33 serotypes (serotypes 1 to 31, 33, and 1/2) of S. suis according to the variation of capsular antigens (5, 6). Two outbreaks of S. suis have occurred in China. One was in Sichuan Province in July 2005, with 215 humans infected. The other was in Jiangsu Province, in 1998, and 25 humans were involved, 14 of whom died (7-9). By the end of 2012, 1,584 cases had been reported in the literature, most of which were associated with pigs and human infections (10). Besides S. suis, S. equi subsp. zooepidemicus is another important pathogen that can cause upper respiratory tract disease in pigs and rheumatic fever and glomerulonephritis in humans (11, 12). S. equi subsp. zooepidemicus shares Ͼ80% DNA sequence similarity and important virulence factors with Streptococcus pyogenes (13). The sequelae of S. pyogenes infections and the symptoms caused by S. equi subsp. zooepidemicus are also similar (12). In recent years, several outbreaks of S. equi subsp. zooepidemicus infections have been reported in different countries (11,14,15).The main and conventional prev...

show abstract

Isolation and identification of a bacteriophage capable of infecting Streptococcus suis type 2 strains

Cited by 37 publications

References 12 publications

Application of a Bacteriophage Lysin To Disrupt Biofilms Formed by the Animal Pathogen Streptococcus suis

Application of a Bacteriophage Lysin To Disrupt Biofilms Formed by the Animal Pathogen Streptococcus suis

Different Genetic Elements Carrying the tet (W) Gene in Two Human Clinical Isolates of Streptococcus suis

Prophage Lysin Ply30 Protects Mice from Streptococcus suis and Streptococcus equi subsp. zooepidemicus Infections

Contact Info

Product

Resources

About