Association between the accessory gene regulator (agr) locus and the presence of superantigen genes in clinical isolates of methicillin-resistant Staphylococcus aureus

Abstract

ObjectiveMethicillin-resistant Staphylococcus aureus cause to a variety of hard to cure infections. MRSA isolates also, produce an arsenal of virulence factors contribute to severe infections. The aim of this study was to find out the relationship between agr locus and presence of S. aureus superantigens (SAgs).ResultsClinical isolates in two groups from two different states of Iran were collected. Antibiotic resistance patterns, agr typing, and virulence factor genes prevalence were identified and relationship between them was analyzed using SPSS software version16. Most of the samples were collected from wound 39 isolates in Group 1 and 61 isolates in Group 2. Frequency of MRSA strains was 38.1% in Group 1 and 52.1% in Group 2. Also, the most common resistance among both groups was to penicillin. agr positive isolates were detected in 132 isolates of Group 1 and 104 isolates of Group 2. In Conclusion, a significant relationship between the SAgs frequency and agr locus in both groups has been indicated. The production of superantigens in S. aureus plays an important role in the classification of agr locus, and this locus can affect differently in methicillin-resistant strains.Electronic supplementary materialThe online version of this article (10.1186/s13104-019-4166-7) contains supplementary material, which is available to authorized users.

Accessory gene regulators and virulence genes associated with the pathogenicity of Staphylococcus aureus from clinical and community settings in Lagos, Nigeria

“…7,8 The agr region is crucial in pathogenesis and actively controls the expression of virulence factors, heterogeneous resistance in methicillin-resistant S. aureus (MRSA), and biofilm development. [9][10][11] It co-regulates the expression of several exoproteins including α-, β-, γ-haemolysin as well as lipases, phenol-soluble modulins and TSST-1 while down regulating the synthesis of cell-wall-associated proteins such as protein A, coagulase, and fibronectin binding protein. 12,13 Several studies have been conducted to investigate the association of agr groups with certain biological traits in S. aureus and the outcomes have indicated that some enterotoxin clusters -namely seg, sei, sem, sen, and seo -are linked to agr 4 in a number of strains.…”

Direct Quantitative Immunochemical Analysis of Autoinducer Peptide IV for Diagnosing and Stratifying Staphylococcus aureus Infections

“…However, it has recently been reported that a minor fraction of these Agr-negative mutants can revert their Agr activity upon phagocytosis . Therefore, agr typing could be of great interest to manage infections and distinguish between colonization and infection. − …”