Epidemiological study on the relationship between toxin production and psm-mec mutations in MRSA isolates in Thailand

Microbiol Immunol. 2020 Mar;64(3):219-225. doi: 10.1111/1348-0421.12764. Epub 2020 Feb 5.

Abstract

In this present study, we investigated the phenol-soluble modulin (psm-mec) mutations, the staphylococcal cassette chromosome mec (SCCmec) types, and toxin production in 102 methicillin-resistant Staphylococcus aureus (MRSA) isolates from the northeast and central regions of Thailand. The MRSA isolates carrying -7T>C psm-mec in Type II SCCmec (n = 18) and the MRSA isolates carrying no psm-mec in Type IV (n = 8) or Type IX SCCmec (n = 4) had higher hemolytic activity against sheep erythrocytes than MRSA isolates carrying intact psm-mec in Type III SCCmec (n = 34), but MRSA isolates carrying no psm-mec in Type I SCCmec (n = 27) did not.

Keywords: MRSA; SCCmec; psm-mec; toxin; virulence.

MeSH terms

  • Animals
  • Bacterial Toxins* / genetics
  • Bacterial Toxins* / metabolism
  • Erythrocytes / pathology
  • Hemolytic Agents / metabolism
  • Humans
  • Methicillin Resistance / genetics
  • Methicillin-Resistant Staphylococcus aureus* / genetics
  • Methicillin-Resistant Staphylococcus aureus* / metabolism
  • Methicillin-Resistant Staphylococcus aureus* / pathogenicity
  • Mutation
  • Sheep
  • Staphylococcal Infections / drug therapy
  • Staphylococcal Infections / epidemiology*
  • Thailand / epidemiology

Substances

  • Bacterial Toxins
  • Hemolytic Agents
  • staphylococcal delta toxin