Novel species-specific targets for real-time PCR detection of four common pathogenic Staphylococcus spp.

Staphylococcus aureus, S. epidermidis, S. haemolyticus, and S. hominis are important pathogenic microorganisms that cause food contamination and clinical infections. This study aimed to develop a rapid, accurate, and monitoring technique for simultaneous detection of these Staphylococcus spp. in food. A total of 19 novel candidate species-specific targets for these four Staphylococcus spp. were mined based on pangenome analysis. Four novel targets (comFA for S. aureus, group_14348 for S. epidermidis, group_26190 for S. haemolyticus, and group_26478 for S. hominis) were selected for quantitative polymerase chain reaction (qPCR). The limit of detection in pure culture without pre-enrichment were 102 colony-forming units (CFU)/mL for S. aureus, 103 CFU/mL for S. epidermidis and S. haemolyticus, and 100 CFU/mL for S. hominis, respectively. This method allowed fast, sensitive, and accurate detection of the target Staphylococcus spp. in actual samples and the presence of nontarget bacteria. The feasibility of this method was satisfying in terms of sensitivity, specificity and efficiency after evaluating 100 samples, as well as being consistent with the national standard detection method. Thus, this qPCR assay, based on novel species-specific targets, allows efficient screening for pathogenic Staphylococcus spp., and may help prevent staphylococcal contamination of food.