Proposal for a method to estimate nutrient shock effects in bacteria

• Type: Article in International Scientific Journal
• Date: 2012

Authors

Nuno F. Azevedo (Author) FEUP; Sofia M. Bragança (Author) Other; Lúcia C. Simões (Author) Other; Laura Cerqueira (Author) Other; Carina Almeida (Author) FEUP; Charles W. Keevil (Author) Other; Maria J. Vieira (Author) Other

Journal

Title: BMC Research Notes

Vol. 5

Final page: 422

ISSN: 1756-0500

Publisher: Springer Nature

Indexing

ISI Web of Knowledge

Scopus - 9 Citations

Associated Projects

PEst-C/EQB/UI0511/2011 - PROJECTO ESTRATÉGICO - UI 511 - 2011-2012

Other information

Authenticus ID: P-008-5AQ

DOI: 10.1186/1756-0500-5-422

Abstract (EN): 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. © 2012 Azevedo et al.; licensee BioMed Central Ltd.

Language: English

Type (Professor's evaluation): Scientific