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Proposal for a method to estimate nutrient shock effects in bacteria

BACKGROUND: Plating methods are still the golden standard in microbiology; however, some studies have shown that these techniques can underestimate the microbial concentrations and diversity. A nutrient shock is one of the mechanisms proposed to explain this phenomenon. In this study, a tentative me...

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Autores principales: Azevedo, Nuno F, Bragança, Sofia M, Simões, Lúcia C, Cerqueira, Laura, Almeida, Carina, Keevil, Charles W, Vieira, Maria J
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2012
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3490807/
https://www.ncbi.nlm.nih.gov/pubmed/22873690
http://dx.doi.org/10.1186/1756-0500-5-422
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author Azevedo, Nuno F
Bragança, Sofia M
Simões, Lúcia C
Cerqueira, Laura
Almeida, Carina
Keevil, Charles W
Vieira, Maria J
author_facet Azevedo, Nuno F
Bragança, Sofia M
Simões, Lúcia C
Cerqueira, Laura
Almeida, Carina
Keevil, Charles W
Vieira, Maria J
author_sort Azevedo, Nuno F
collection PubMed
description BACKGROUND: Plating methods are still the golden standard in microbiology; however, some studies have shown that these techniques can underestimate the microbial concentrations and diversity. A nutrient shock is one of the mechanisms proposed to explain this phenomenon. In this study, a tentative method to assess nutrient shock effects was tested. FINDINGS: To estimate the extent of nutrient shock effects, two strains isolated from tap water (Sphingomonas capsulata and Methylobacterium sp.) and two culture collection strains (E. coli CECT 434 and Pseudomonas fluorescens ATCC 13525) were exposed both to low and high nutrient conditions for different times and then placed in low nutrient medium (R2A) and rich nutrient medium (TSA). The average improvement (A.I.) of recovery between R2A and TSA for the different times was calculated to more simply assess the difference obtained in culturability between each medium. As expected, A.I. was higher when cells were plated after the exposition to water than when they were recovered from high-nutrient medium showing the existence of a nutrient shock for the diverse bacteria used. S. capsulata was the species most affected by this phenomenon. CONCLUSIONS: This work provides a method to consistently determine the extent of nutrient shock effects on different microorganisms and hence quantify the ability of each species to deal with sudden increases in substrate concentration.
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spelling pubmed-34908072012-11-08 Proposal for a method to estimate nutrient shock effects in bacteria Azevedo, Nuno F Bragança, Sofia M Simões, Lúcia C Cerqueira, Laura Almeida, Carina Keevil, Charles W Vieira, Maria J BMC Res Notes Technical Note BACKGROUND: Plating methods are still the golden standard in microbiology; however, some studies have shown that these techniques can underestimate the microbial concentrations and diversity. A nutrient shock is one of the mechanisms proposed to explain this phenomenon. In this study, a tentative method to assess nutrient shock effects was tested. FINDINGS: To estimate the extent of nutrient shock effects, two strains isolated from tap water (Sphingomonas capsulata and Methylobacterium sp.) and two culture collection strains (E. coli CECT 434 and Pseudomonas fluorescens ATCC 13525) were exposed both to low and high nutrient conditions for different times and then placed in low nutrient medium (R2A) and rich nutrient medium (TSA). The average improvement (A.I.) of recovery between R2A and TSA for the different times was calculated to more simply assess the difference obtained in culturability between each medium. As expected, A.I. was higher when cells were plated after the exposition to water than when they were recovered from high-nutrient medium showing the existence of a nutrient shock for the diverse bacteria used. S. capsulata was the species most affected by this phenomenon. CONCLUSIONS: This work provides a method to consistently determine the extent of nutrient shock effects on different microorganisms and hence quantify the ability of each species to deal with sudden increases in substrate concentration. BioMed Central 2012-08-08 /pmc/articles/PMC3490807/ /pubmed/22873690 http://dx.doi.org/10.1186/1756-0500-5-422 Text en Copyright ©2012 Azevedo et al.; licensee BioMed Central Ltd. http://creativecommons.org/licenses/by/2.0 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
spellingShingle Technical Note
Azevedo, Nuno F
Bragança, Sofia M
Simões, Lúcia C
Cerqueira, Laura
Almeida, Carina
Keevil, Charles W
Vieira, Maria J
Proposal for a method to estimate nutrient shock effects in bacteria
title Proposal for a method to estimate nutrient shock effects in bacteria
title_full Proposal for a method to estimate nutrient shock effects in bacteria
title_fullStr Proposal for a method to estimate nutrient shock effects in bacteria
title_full_unstemmed Proposal for a method to estimate nutrient shock effects in bacteria
title_short Proposal for a method to estimate nutrient shock effects in bacteria
title_sort proposal for a method to estimate nutrient shock effects in bacteria
topic Technical Note
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3490807/
https://www.ncbi.nlm.nih.gov/pubmed/22873690
http://dx.doi.org/10.1186/1756-0500-5-422
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