Virulence genes spectrum and spermatozoal immobilization phenomenon of Staphylococcus aureus strains from genitourinary infection associated with infertility

Objective To study the effect of Staphylococcus aureus from sperm of infertile male patients with genital urinary infection on spermatozoa,as well as the virulence genes spectrum of these Staphylococcus aureus.Methods A total of 89 strains of Staphylococcus aureus were isolated from infertility males'sperm between December 2009 and January 2011.The ATCC29213 strain of Staphylococcus aureus were considered as negative control.Computer assisted system:Sperm Class Analyzer V.3.2.0 was used to screen the influence of all strain on the robust semen according to the semen analysis method in the WHO (2010) guideline.The antimicrobial susceptibility test of all isolated strains was performed by agar dilution method including the common antibiotics,quinolones,sulfonamides and so on.The methicillin-resistant Staphylococcus aureus (MRSA) were determined by Cefoxitin disk diffusion and Polymerase Chain Reaction (PCR) for mecA gene.SCCmec genotypes were conformed via Multiplex-PCR and DNA sequencing,the virulence genes were also detected by PCR method.Results Twenty-two strains of Staphylococcus aureus could significiantly weaken the mobility of spermatozoahe than the ability in the negative control Staphylococcus aureus ATCC29213 (P＜0.05).The remainning 67 isolates could not inhibit the activity of sperm (P＞ 0.05).All the isolates were sensitive to the vancomycin,linezolid and furadantin.Instead,they displayed high-level antibiotics resistance to fluoroquinolones (Ciprofloxacin,levofloxacin),erythromycin,gentamicin and tetracycline.Among the 51 MRSA isolates,the SCCmec genotypes were shown as follows:SCCmec Ⅰ was indentified in 2 isolates,SCCmec Ⅲ in 12 isolates,SCCmec Ⅳ in 2 isolates,SCCmec Ⅴ in 25 isolates,the remaining ten were undefined genotyping.The putative 14 virulence determinants in the 89 isolates were detected by PCR,results were shown as follows:22 isolates of S.aureus had gene for hlg,3 isolates for see,1 isolate for sea,1 isolate for seg,1 isolate for sei,only 1 isolate had genes for hlg and sea simultaneously and 1 for seg and sei simultaneously.Conclusions The Staphylococcus aureus isolated from urogenital tract of infertile male patients with genitourinary infection could inhibit significantly the mobility of spermatozoa; In our research,the primary virulence determinate was hlg encoding γ-hemolysin,and the gene sea,see,seg and sei,which encoded enterotoxins were also scatteredly distributed in the Staphylococcus aureus. Key words: Infertility;  Urogenital tract infection;  Staphylococcus aureus ;  Staphylococcal Cassette Chromosome mec;  Virulence