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NaCl stress impact on the key enzymes in glycolysis from Lactobacillus bulgaricus during freeze-drying

The viability of Lactobacillus bulgaricus in freeze-drying is of significant commercial interest to dairy industries. In the study, L.bulgaricus demonstrated a significantly improved (p < 0.05) survival rate during freeze-drying when subjected to a pre-stressed period under the conditions of 2% (...

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Detalles Bibliográficos
Autores principales: Li, Chun, Sun, Jinwei, Qi, Xiaoxi, Liu, Libo
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Sociedade Brasileira de Microbiologia 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4704629/
https://www.ncbi.nlm.nih.gov/pubmed/26691481
http://dx.doi.org/10.1590/S1517-838246420140595
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author Li, Chun
Sun, Jinwei
Qi, Xiaoxi
Liu, Libo
author_facet Li, Chun
Sun, Jinwei
Qi, Xiaoxi
Liu, Libo
author_sort Li, Chun
collection PubMed
description The viability of Lactobacillus bulgaricus in freeze-drying is of significant commercial interest to dairy industries. In the study, L.bulgaricus demonstrated a significantly improved (p < 0.05) survival rate during freeze-drying when subjected to a pre-stressed period under the conditions of 2% (w/v) NaCl for 2 h in the late growth phase. The main energy source for the life activity of lactic acid bacteria is related to the glycolytic pathway. To investigate the phenomenon of this stress-related viability improvement in L. bulgaricus, the activities and corresponding genes of key enzymes in glycolysis during 2% NaCl stress were studied. NaCl stress significantly enhanced (p < 0.05) glucose utilization. The activities of glycolytic enzymes (phosphofructokinase, pyruvate kinase, and lactate dehydrogenase) decreased during freeze-drying, and NaCl stress were found to improve activities of these enzymes before and after freeze-drying. However, a transcriptional analysis of the corresponding genes suggested that the effect of NaCl stress on the expression of the pfk2 gene was not obvious. The increased survival of freeze-dried cells of L. bulgaricus under NaCl stress might be due to changes in only the activity or translation level of these enzymes in different environmental conditions but have no relation to their mRNA transcription level.
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spelling pubmed-47046292016-01-14 NaCl stress impact on the key enzymes in glycolysis from Lactobacillus bulgaricus during freeze-drying Li, Chun Sun, Jinwei Qi, Xiaoxi Liu, Libo Braz J Microbiol Food Microbiology The viability of Lactobacillus bulgaricus in freeze-drying is of significant commercial interest to dairy industries. In the study, L.bulgaricus demonstrated a significantly improved (p < 0.05) survival rate during freeze-drying when subjected to a pre-stressed period under the conditions of 2% (w/v) NaCl for 2 h in the late growth phase. The main energy source for the life activity of lactic acid bacteria is related to the glycolytic pathway. To investigate the phenomenon of this stress-related viability improvement in L. bulgaricus, the activities and corresponding genes of key enzymes in glycolysis during 2% NaCl stress were studied. NaCl stress significantly enhanced (p < 0.05) glucose utilization. The activities of glycolytic enzymes (phosphofructokinase, pyruvate kinase, and lactate dehydrogenase) decreased during freeze-drying, and NaCl stress were found to improve activities of these enzymes before and after freeze-drying. However, a transcriptional analysis of the corresponding genes suggested that the effect of NaCl stress on the expression of the pfk2 gene was not obvious. The increased survival of freeze-dried cells of L. bulgaricus under NaCl stress might be due to changes in only the activity or translation level of these enzymes in different environmental conditions but have no relation to their mRNA transcription level. Sociedade Brasileira de Microbiologia 2015-12-01 /pmc/articles/PMC4704629/ /pubmed/26691481 http://dx.doi.org/10.1590/S1517-838246420140595 Text en Copyright © 2015, Sociedade Brasileira de Microbiologia http://creativecommons.org/licenses/by-nc/4.0/ All the content of the journal, except where otherwise noted, is licensed under a Creative Commons License CC-BY.
spellingShingle Food Microbiology
Li, Chun
Sun, Jinwei
Qi, Xiaoxi
Liu, Libo
NaCl stress impact on the key enzymes in glycolysis from Lactobacillus bulgaricus during freeze-drying
title NaCl stress impact on the key enzymes in glycolysis from Lactobacillus bulgaricus during freeze-drying
title_full NaCl stress impact on the key enzymes in glycolysis from Lactobacillus bulgaricus during freeze-drying
title_fullStr NaCl stress impact on the key enzymes in glycolysis from Lactobacillus bulgaricus during freeze-drying
title_full_unstemmed NaCl stress impact on the key enzymes in glycolysis from Lactobacillus bulgaricus during freeze-drying
title_short NaCl stress impact on the key enzymes in glycolysis from Lactobacillus bulgaricus during freeze-drying
title_sort nacl stress impact on the key enzymes in glycolysis from lactobacillus bulgaricus during freeze-drying
topic Food Microbiology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4704629/
https://www.ncbi.nlm.nih.gov/pubmed/26691481
http://dx.doi.org/10.1590/S1517-838246420140595
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