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[Biological properties, phage typing and antimicrobial susceptibility of Staphylococcus aureus isolated from
Abstract:
The characteristics of 167 isolates of S. aureus from 106 mice suffering dermatitis were examined. All 167 isolates coagulated both rabbit and human plasmas and 161 of them also coagulated bovine plasma. All the isolates produced heat-stable and heat-labile DNase, phosphatase and yellow pigment, reduced nitrate, hydrolysed egg yolk, Tween 80, and hippurate, and grew on crystal violet agar in colonies of the negative type C and on medium with 10% NaCl. The majority of them produced fibrinolysin, protease and acetoin. Fifty-three percent were gelatinase positive. In hemolysis tests, 25, 57 and 45 isolates showed alpha-, beta-, alpha beta-hemolysis, respectively. Forty isolates did not produce hemolysins in the rabbit and sheep blood agar. All of 75 isolates tested produced acid from fructose, galactose, glucose, glycerol and mannose, but did not from arabinose, dextrin, inulin, raffinose, salicin, sorbitol and xylose. Most of these isolates produced acid from lactose, mannitol, sucrose and trehalose. All of the 75 isolates were highly sensitive to penicillin, methylphenylisoxazolyl penicillin, erythromycin, spiramycin, lincomycin, chloramphenicol, tetracycline, kanamycin, gentamicin and cephaloridine, but were resistant to sulfisoxazole. With phages of human set, all 167 isolates were typable at 100 X RTD. All but one of the typable isolates belonged to mixed lytic groups. These were I + III (35 isolates), I + M (1), I + III + M (124) and I + II + III + M (6), with long phage patterns. When the 167 isolates were biotyped as described by Hájek and Marsálek [7, 8], 5 belonged to biotype A, 1 to biotype B and 60 to biotype C.(ABSTRACT TRUNCATED AT 250 WORDS)
Insights
This study characterized 167 Staphylococcus aureus isolates from mice with dermatitis, revealing consistent biochemical profiles and high sensitivity to multiple antibiotics. Phage typing showed most isolates belonged to mixed lytic groups.
Area of Science:
- Microbiology
- Bacterial Pathogenesis
- Veterinary Dermatology
Context:
- Staphylococcus aureus is a significant pathogen in both human and animal health.
- Dermatitis in mice can be caused by various bacterial agents, including S. aureus.
- Understanding the characteristics of S. aureus isolates is crucial for effective treatment and control.
Purpose:
- To comprehensively characterize 167 Staphylococcus aureus isolates obtained from mice with dermatitis.
- To evaluate the biochemical properties, antibiotic susceptibility, and phage typing patterns of these isolates.
- To determine the biotype distribution of the S. aureus isolates.
Summary:
- All 167 S. aureus isolates exhibited consistent coagulase activity and produced DNase, phosphatase, and pigment. They showed diverse hemolytic patterns and acid production from various carbohydrates.
- Antibiotic susceptibility testing revealed high sensitivity to most tested antibiotics, except sulfisoxazole. Phage typing indicated that most isolates were typable and belonged to mixed lytic groups.
- Biotyping classified the isolates into groups A, B, and C, with a majority belonging to biotype C.
Impact:
- Provides detailed phenotypic and genotypic data on S. aureus isolates from a specific animal model.
- Informs potential therapeutic strategies by highlighting antibiotic sensitivities and resistance patterns.
- Contributes to the epidemiological understanding of S. aureus strains in veterinary contexts.