ABSTRACT
The staphylococci are important pathogenic bacteria causing various infections in animals and human. Hemolysin is one of the virulence factors of coagulase-positive [CPS] and coagulase-negative staphylococci [CNS]. The aims of the study were to characterize hemolysins of Staphylococcus spp. isolated from human and bovine origin, phenotypic- and genotypically. Characterization of hemolysin phenotypically based on hemolysis pattern of Staphylococcus spp. was done on the sheep, horse and rabbit blood agar plates. Genes encoding hemolysin were amplified with specific primers by using polymerase chain reaction [PCR] technique. Hemolytic activities phenotypically were determined in 60 and 90% of the total bovine and human isolates, respectively. All non hemolytic isolates were CNS [P=0.05]. In all isolates, hla and hid genes were determined by PCR amplification. None of the bovine and human isolates showed phenotypically and genotypically gamma hemolysin. The results from this study suggest that, in accordance with what is generally believed, some differences are apparent in hemolysin types among Staphylococcus strains of bovine and human origin. Furthermore, this study showed that CNS can be important as new pathogens
Subject(s)
Animals , Hemolysin Proteins , Polymerase Chain ReactionABSTRACT
The objective of this study was to investigate the genotypic characteristics of Campylobacter isolates in Shiraz, Iran. A total of 40 Campylobacter isolates including 20 C. jejuni and 20 C. coli were recovered from both cattle and sheep faeces by cultivation methods. The isolates were identified on the basis of polymerase chain reaction [PCR] detection of 16SrRNA and multiplex PCR to determine two species. For confirmed isolates, PCR was carried out for the presence of virulence genes using specific primers. Other than verifying the genetic diversity of thermophilic Campylobacter isolates, flaA PCR-RFLP was performed. Results showed the high prevalence [100%] of the cadF gene and three genes associated with cytolethal distending toxin [CDT]. Plasmid virB11 gene was not found in any Campylobacter isolate, and dissimilarities and discrepancies occurred in pldA, iamA, wlaN, waaC and cgtB genes. Among the 40 Campylobacter isolates studied, nine different types were defined by flaA-typing. Results indicated genetic diversity among Campylobacter isolates recovered from cattle and sheep faecal samples. Findings showed the potential ability of C. jejuni and C. coli with cattle and sheep origins to cause infection in humans