Expression of toxic shock syndrome toxin-1 gene of Staphylococcus aureus in milk: Proof of concept

The aim of this study was to assess the expression of a toxic shock syndrome toxin-1 (TSST-1) gene of Staphylococcus aureus in different types of milk, depending on inadequate temperature and storage conditions. Pasteurized and UHT milk were inoculated with monotoxic TSST-1 strain of S. aureus and g...

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Main Authors: Milijana Babić, Marija Pajić, Aleksandra Nikolić, Vlado Teodorović, Milorad Mirilović, Lazar Milojević, Branko Velebit
Format: Article
Language:English
Published: Croatian Dairy Union 2018-01-01
Series:Mljekarstvo
Subjects:
Online Access:https://hrcak.srce.hr/file/283663
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author Milijana Babić
Marija Pajić
Aleksandra Nikolić
Vlado Teodorović
Milorad Mirilović
Lazar Milojević
Branko Velebit
author_facet Milijana Babić
Marija Pajić
Aleksandra Nikolić
Vlado Teodorović
Milorad Mirilović
Lazar Milojević
Branko Velebit
author_sort Milijana Babić
collection DOAJ
description The aim of this study was to assess the expression of a toxic shock syndrome toxin-1 (TSST-1) gene of Staphylococcus aureus in different types of milk, depending on inadequate temperature and storage conditions. Pasteurized and UHT milk were inoculated with monotoxic TSST-1 strain of S. aureus and growth kinetics was determined by the drop plate method using Baird-Parker agar medium in accordance with EN ISO 6888-1. The patterns of gene regulation were detected by quantitative reverse transcriptase PCR. Relative quantification method for statistical significance testing was used to detect significant gene expression responses. The results of experiments showed the dependence of the growth rate and consequent up-regulation of TSST-1 encoding gene on storage time-temperature and type of milk. In contaminated pasteurized and UHT milk kept at both 15 °C and 22 °C S. aureus significantly increased its virulent potential over time. This effect was a bit more emphasized in UHT milk serving as a “proof of concept”. Possible explanation could be a presence of lactic acid bacteria in pasteurized milk which is known to have down-regulatory effect on TSST-1 gene. Maintenance of the milk storage temperature below 8 °C and employment of microbiological control measures in hygienic practices, from milk producer through retailer and on to the consumer is of utmost importance to decrease risk of non-emetic staphylococcal poisoning.
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spelling doaj-art-a5cb2b42e07d473290b3b61dbc80c48f2025-08-20T03:20:00ZengCroatian Dairy UnionMljekarstvo0026-704X1846-40252018-01-01681122010.15567/mljekarstvo.2018.0102Expression of toxic shock syndrome toxin-1 gene of Staphylococcus aureus in milk: Proof of conceptMilijana Babić0Marija Pajić1Aleksandra Nikolić2Vlado Teodorović3Milorad Mirilović4Lazar Milojević5Branko VelebitFaculty of Veterinary Medicine, University of Belgrade, Bul. Oslobođenja 18, 11000 Belgrade, SerbiaFaculty of Agriculture, University of Novi Sad, Trg Dositeja Obradovića 8, 21000 Novi Sad, SerbiaInstitute of Meat Hygiene and Technology, Kaćanskog 13, 11040 Belgrade, SerbiaFaculty of Veterinary Medicine, University of Belgrade, Bul. Oslobođenja 18, 11000 Belgrade, SerbiaFaculty of Veterinary Medicine, University of Belgrade, Bul. Oslobođenja 18, 11000 Belgrade, SerbiaInstitute of Meat Hygiene and Technology, Kaćanskog 13, 11040 Belgrade, SerbiaThe aim of this study was to assess the expression of a toxic shock syndrome toxin-1 (TSST-1) gene of Staphylococcus aureus in different types of milk, depending on inadequate temperature and storage conditions. Pasteurized and UHT milk were inoculated with monotoxic TSST-1 strain of S. aureus and growth kinetics was determined by the drop plate method using Baird-Parker agar medium in accordance with EN ISO 6888-1. The patterns of gene regulation were detected by quantitative reverse transcriptase PCR. Relative quantification method for statistical significance testing was used to detect significant gene expression responses. The results of experiments showed the dependence of the growth rate and consequent up-regulation of TSST-1 encoding gene on storage time-temperature and type of milk. In contaminated pasteurized and UHT milk kept at both 15 °C and 22 °C S. aureus significantly increased its virulent potential over time. This effect was a bit more emphasized in UHT milk serving as a “proof of concept”. Possible explanation could be a presence of lactic acid bacteria in pasteurized milk which is known to have down-regulatory effect on TSST-1 gene. Maintenance of the milk storage temperature below 8 °C and employment of microbiological control measures in hygienic practices, from milk producer through retailer and on to the consumer is of utmost importance to decrease risk of non-emetic staphylococcal poisoning.https://hrcak.srce.hr/file/283663S. aureustoxic shock syndrome toxin-1milk
spellingShingle Milijana Babić
Marija Pajić
Aleksandra Nikolić
Vlado Teodorović
Milorad Mirilović
Lazar Milojević
Branko Velebit
Expression of toxic shock syndrome toxin-1 gene of Staphylococcus aureus in milk: Proof of concept
Mljekarstvo
S. aureus
toxic shock syndrome toxin-1
milk
title Expression of toxic shock syndrome toxin-1 gene of Staphylococcus aureus in milk: Proof of concept
title_full Expression of toxic shock syndrome toxin-1 gene of Staphylococcus aureus in milk: Proof of concept
title_fullStr Expression of toxic shock syndrome toxin-1 gene of Staphylococcus aureus in milk: Proof of concept
title_full_unstemmed Expression of toxic shock syndrome toxin-1 gene of Staphylococcus aureus in milk: Proof of concept
title_short Expression of toxic shock syndrome toxin-1 gene of Staphylococcus aureus in milk: Proof of concept
title_sort expression of toxic shock syndrome toxin 1 gene of staphylococcus aureus in milk proof of concept
topic S. aureus
toxic shock syndrome toxin-1
milk
url https://hrcak.srce.hr/file/283663
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