A simple, quantitative assay for the detection of viable but non-culturable (VBNC) bacteria.
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ABSTRACT:
SUBMITTER: Arvizu IS
PROVIDER: S-EPMC8365524 | biostudies-literature | 2021 Sep
REPOSITORIES: biostudies-literature
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A simple, quantitative assay for the detection of viable but non-culturable (VBNC) bacteria.
Arvizu Ignacio Servando IS Murray Sean Richard SR
STAR protocols 20210812 3
This protocol determines the fraction of a bacterial population that is viable and culturable, viable and non-culturable, or non-viable (dead). Each population is detected by isolating colonies on agar plates, performing direct counts, and staining for live or dead cells. Its application is limited to bacteria that are stainable and when permissible growth conditions are known. The quantitative data extracted allow for the detection of a viable but non-culturable (alive and non-dividing) populat ...[more]
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Project description:The phenomenon of viable but non-culturable (VBNC) referred as a dormant state of non-sporulating bacteria enhancing the survival in adverse environments. To our knowledge, only few studies have been performed on whole genomic expression of V. parahaemolyticus in VBNC state compared with cells in exponential and early stationary phases. Since many VBNC state studies found DNA, RNA and protein degradation, we hypothesise that gene regulation of VBNC cells is highly reduced, down-regulation of gene expression is dominant and only metabolic functions crucial for survival are kept on a sustained basis. In the VBNC state we found 509 significantly induced genes and 309 significantly repressed by more than twofold compared with unstressed phases among 4820 investigated genes (adjusted P-value < 0.05). Furthermore, up-regulation was dominant in most of the non-metabolism functional categories, while five metabolism-related functional categories revealed down-regulation in the VBNC state. To our knowledge, this is the first study of comprehensive transcriptomic analyses of three phases of V. parahaemolyticus RIMD2210633. Although the mechanism of VBNC state is not yet clear, massive regulation of gene expression occurs in the VBNC state compared with expression in unstressed phases and thus, VBNC cells are active cells.
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