Molecular Characterization of Staphylococcus aureus Isolated from Human and Food Samples in Northern Algeria.

Rachid Achek,Ibrahim Nabi,Herbert Tomaso,Heinrich Neubauer,Stefan Monecke,Ralf Ehricht,Helmut Hotzel,Taha Mossadak Hamdi,Ashraf Hendam,Hosny El-Adawy

doi:10.3390/pathogens10101276

Abstract

Staphylococcus aureus is a commensal resident of the skin and nasal cavities of humans and can cause various infections. Some toxigenic strains can contaminate food matrices and cause foodborne intoxications. The present study aimed to provide relevant information (clonal complex lineages, agr types, virulence and antimicrobial resistance-associated genes) based on DNA microarray analyses as well as the origins and dissemination of several circulating clones of 60 Staphylococcus aureus isolated from food matrices (n = 24), clinical samples (n = 20), and nasal carriers (n = 16) in northern Algeria. Staphylococcus aureus were genotyped into 14 different clonal complexes. Out of 60 S. aureus, 13 and 10 isolates belonged to CC1-MSSA and CC97-MSSA, respectively. The CC 80-MRSA-IV was the predominant S. aureus strain in clinical isolates. The accessory gene regulator allele agr group III was mainly found among clinical isolates (70.4%). Panton–Valentine leukocidin genes lukF/lukS-PV were detected in 13.3% of isolates that all belonged to CC80-MRSA. The lukF/S-hlg, hlgA, and hla genes encoding for hemolysins and leucocidin components were detected in all Staphylococcus aureus isolates. Clinical and food isolates harbored more often the antibiotic resistance genes markers. Seventeen (28.3%) methicillin-resistant Staphylococcus aureus carrying the mecA gene localized on a SCCmec type IV element were identified. The penicillinase operon (blaZ/I/R) was found in 71.7% (43/60) of isolates. Food isolates belonging to CC97-MSSA carried several antibiotic resistance genes (blaZ, ermB, aphA3, sat, tetM, and tetK). The results of this study showed that all clones were found in their typical host, but interestingly, some nasal carriers had isolates assigned to CC705 thought to be absent in humans. The detection of MRSA strains among food isolates should be considered as a potential public health risk. Therefore, controlling the antibiotics prescription for a rational use in human and animal infections is mandatory.

Highlights

Staphylococcus aureus is a Gram-positive bacterium, considered as a commensal resident of the skin and nasal cavities of humans and animals
Staphylococcus aureus isolated in this study were grouped into 14 different clonal complexes using DNA microarray analysis (Table 1; Figure 1 and Table S1)
The DNA microarray results obtained in this study showed that clonal complexes (CC) 80-methicillin-resistantS. aureus (MRSA)- IV

Summary

Introduction

Staphylococcus aureus is a Gram-positive bacterium, considered as a commensal resident of the skin and nasal cavities of humans and animals. This bacterium can spread from its habitual niches to other parts of the body and cause various clinical infections [1,2] and foodborne intoxications [3]. The study of the clonal diversity among S. aureus using molecular techniques contributed to our understanding of the genetic diversity of S. aureus and provided insights into the origin and spread of MRSA into humans and animals [10,11]

Objectives

Methods

Results

Discussion

Conclusion