Advanced

Effect of sodium nitrite and regulatory mutations Δagr, ΔsarA, and ΔsigB on the mRNA and protein levels of staphylococcal enterotoxin D

Sihto, Henna Maria; Budi Susilo, Yusak LU ; Tasara, Taurai; Rådström, Peter LU ; Stephan, Roger; Schelin, Jenny LU and Johler, Sophia (2016) In Food Control 65. p.37-45
Abstract

Staphylococcal food poisoning results from ingestion of enterotoxins produced by Staphylococcus aureus. Staphylococcal enterotoxin D (SED) is one of the most common toxins detected in S. aureus strains associated with intoxications. The effect of sodium nitrite on enterotoxin production has been only partly investigated, despite its wide usage in meat products. In addition, the factors influencing SED regulation are unclear. The aim of this study was to determine the effect of sodium nitrite on sed transcription and SED production, as well as the effect of regulatory mutations on SED protein levels. Temporal sed mRNA and SED protein levels were compared in LB and LB supplemented with 150 mg/L nitrite, and SED protein levels between wild... (More)

Staphylococcal food poisoning results from ingestion of enterotoxins produced by Staphylococcus aureus. Staphylococcal enterotoxin D (SED) is one of the most common toxins detected in S. aureus strains associated with intoxications. The effect of sodium nitrite on enterotoxin production has been only partly investigated, despite its wide usage in meat products. In addition, the factors influencing SED regulation are unclear. The aim of this study was to determine the effect of sodium nitrite on sed transcription and SED production, as well as the effect of regulatory mutations on SED protein levels. Temporal sed mRNA and SED protein levels were compared in LB and LB supplemented with 150 mg/L nitrite, and SED protein levels between wild type (wt) and isogenic regulatory mutants (Δ. agr, Δ. sarA, Δ. sigB) under control and sodium nitrite conditions. Relative sed mRNA levels of wt strains were higher in late stationary phase in the presence of nitrite compared to control conditions. However, SED protein levels were decreased in the presence of nitrite. In LB, Δ. agr mutants showed SED levels similar to the wt, while Δ. sarA mutants exhibited reduced and Δ. sigB mutants increased SED levels compared to the wt. In LB with sodium nitrite, SED levels of mutant strains were reduced similar to the wt strains, except for two Δ. agr mutants, in which SED levels were increased in the presence of nitrite. Overall, strain-specific variation with regard to the effect of regulatory mutations was observed. In addition, the data suggests that SED regulation may not be as tightly dependent on Agr as previously described.

(Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Enterotoxin D formation, Regulatory response, Sed expression, Sodium nitrite, Staphylococcus aureus
in
Food Control
volume
65
pages
9 pages
publisher
Elsevier
external identifiers
  • Scopus:84955280545
ISSN
0956-7135
DOI
10.1016/j.foodcont.2016.01.007
language
English
LU publication?
yes
id
4ac58eb9-5c1b-4eca-a520-11fc81689eba
date added to LUP
2016-04-26 13:52:43
date last changed
2016-10-13 05:07:01
@misc{4ac58eb9-5c1b-4eca-a520-11fc81689eba,
  abstract     = {<p>Staphylococcal food poisoning results from ingestion of enterotoxins produced by Staphylococcus aureus. Staphylococcal enterotoxin D (SED) is one of the most common toxins detected in S. aureus strains associated with intoxications. The effect of sodium nitrite on enterotoxin production has been only partly investigated, despite its wide usage in meat products. In addition, the factors influencing SED regulation are unclear. The aim of this study was to determine the effect of sodium nitrite on sed transcription and SED production, as well as the effect of regulatory mutations on SED protein levels. Temporal sed mRNA and SED protein levels were compared in LB and LB supplemented with 150 mg/L nitrite, and SED protein levels between wild type (wt) and isogenic regulatory mutants (Δ. agr, Δ. sarA, Δ. sigB) under control and sodium nitrite conditions. Relative sed mRNA levels of wt strains were higher in late stationary phase in the presence of nitrite compared to control conditions. However, SED protein levels were decreased in the presence of nitrite. In LB, Δ. agr mutants showed SED levels similar to the wt, while Δ. sarA mutants exhibited reduced and Δ. sigB mutants increased SED levels compared to the wt. In LB with sodium nitrite, SED levels of mutant strains were reduced similar to the wt strains, except for two Δ. agr mutants, in which SED levels were increased in the presence of nitrite. Overall, strain-specific variation with regard to the effect of regulatory mutations was observed. In addition, the data suggests that SED regulation may not be as tightly dependent on Agr as previously described.</p>},
  author       = {Sihto, Henna Maria and Budi Susilo, Yusak and Tasara, Taurai and Rådström, Peter and Stephan, Roger and Schelin, Jenny and Johler, Sophia},
  issn         = {0956-7135},
  keyword      = {Enterotoxin D formation,Regulatory response,Sed expression,Sodium nitrite,Staphylococcus aureus},
  language     = {eng},
  month        = {07},
  pages        = {37--45},
  publisher    = {ARRAY(0x7d91ab8)},
  series       = {Food Control},
  title        = {Effect of sodium nitrite and regulatory mutations Δagr, ΔsarA, and ΔsigB on the mRNA and protein levels of staphylococcal enterotoxin D},
  url          = {http://dx.doi.org/10.1016/j.foodcont.2016.01.007},
  volume       = {65},
  year         = {2016},
}