Safety hazards in bacteriocinogenic Staphylococcus strains isolated from goat and sheep milk. (March 2018)

• Record Type: Journal Article
• Authors: Rahmdel, Samane; Hosseinzadeh, Saeid; Shekarforoush, Seyed Shahram; Torriani, Sandra; Gatto, Veronica; Pashangeh, Safoora
• Is Part Of: Microbial pathogenesis. Volume 116(2018)
• Page Start: 100
• Page End: 108
• Publication Date: 2018-03
• Subjects: Antibiotic resistance -- Biogenic amines -- Bacteriocins -- Enterotoxin -- Staphylococcus -- Safety; Pathogenic microorganisms -- Periodicals; Pathology, Molecular -- Periodicals; Communicable Diseases -- microbiology -- Periodicals; Communicable Diseases -- parasitology -- Periodicals; Micro-organismes pathogènes -- Périodiques; Pathologie moléculaire -- Périodiques; Electronic journals; 616.9041
• DOI: 10.1016/j.micpath.2018.01.016
• Languages: English
• ISSNs: 0882-4010

Abstract

Abstract: In this study, 28 bacteriocinogenic Staphylococcus strains isolated from goat and sheep milk were subjected to the PCR detection of enterotoxin genes ( sea - see ), enterotoxin-like toxin Q gene ( selq ), toxic shock syndrome toxin gene ( tst1 ), and antibiotic resistance genes. They were also evaluated for phenotypic resistance against 10 antibiotics and hemolytic activity. The tyramine and histamine production was investigated using the agar plate assay and capillary zone electrophoretic analysis (CZE). Twenty-five isolates harbored at least one enterotoxin gene. The gene sec was the most frequent (89%). The gene tst1 was found in 84% of sec -positive isolates. The occurrence of antibiotic resistance genes was in the order of blaZ / tetK (100%), mecA / ermB (86%), ermC (50%), and tetM (18%). The genes ermA, aac ( 6 ′) Ie-aph ( 2 ″) Ia, vanA, and vanB were absent in all the isolates. Nineteen isolates were phenotypically susceptible to all the antibiotics. The only isolate with phenotypic resistance to penicillin G and oxacillin was S. epidermidis 4S93 which had a different Sma I-PFGE profile from those of the other S. epidermidis strains. All the S . haemolyticus and S. pseudintermedius isolates were not susceptible to trimethoprim. Twenty-five isolates showed complete or partial hemolytic activity. None of the isolates was able to decarboxylate tyrosine, while CZE analysis revealed histamine formation activity in S . haemolyticus 4S12. The occurrence of safety risks in the isolates reinforces the need for regular monitoring of food-producing animals to mitigate the risks of multidrug resistant and zoonotic pathogens. Moreover, none of the isolates fulfilled the safety criteria to be used as starter cultures or biopreservatives. Highlights: 28 bacteriocinogenic staphylococci from goat and sheep milk were investigated. 25 isolates harbored at least one virulence gene. Capillary zone electrophoretic analysis showed histamine production in one strain. 68% of isolates were phenotypically susceptible to all antibiotics tested. All the isolates harbored more than two antibiotic resistance genes.