Viable but nonculturable (VBNC) bacteria refers as to bacteria that are in a state of very low metabolic activity and do not divide, but are alive and have the ability to become culturable once resuscitated.[1]
Bacteria in a VBNC state cannot grow on standard growth media, though flow cytometry can measure the viability of the bacteria.[1] Bacteria can enter the VBNC state as a response to stress, due to adverse nutrient, temperature, osmotic, oxygen, and light conditions.[1] The cells that are in the VBNC state are morphologically smaller, and demonstrate reduced nutrient transport, rate of respiration, and synthesis of macromolecules.[1] Sometimes, VBNC bacteria can remain in that state for over a year.[1] It has been shown that numerous pathogens and non-pathogens can enter the VBNC state, and therefore it has significant implications in pathogenesis, bioremediation, and other branches of microbiology.[1]
The existence of the VBNC state is controversial. The validity and interpretation of the assays to determine the VBNC state have been questioned.[2]
Species known to enter a VBNC state:[3]
- E.M.S
- Aeromonas salmonicida
- Agrobacterium tumefaciens
- Burkholderia cepacia
- Burkholderia pseudomallei
- Brettanomyces bruxellensis[4]
- Campylobacter coli
- Campylobacter jejuni
- Campylobacter lari
- Cytophaga allerginae
- Enterobacter aerogenes
- Enterobacter cloacae
- Enterococcus faecalis
- Enterococcus hirae
- Enterococcus faecium
- Erwinia amylovora
- Escherichia coli (including EHEC)
- Francisella tularensis
- Helicobacter pylori
- Klebsiella aerogenes
- Klebsiella pneumoniae
- Klebsiella planticola
- Legionella pneumophila
- Listeria monocytogenes
- Micrococcus luteus
- Mycobacterium tuberculosis
- Mycobacterium smegmatis
- Pasteurella piscicida
- Pseudomonas aeruginosa
- Pseudomonas syringae
- Ralstonia solanacearum
- Rhizobium leguminosarum
- Rhizobium meliloti
- Salmonella enterica
- Salmonella Typhi
- Salmonella Typhimurium
- Serratia marcescens
- Shigella dysenteriae
- Shigella flexneri
- Shigella sonnei
- Streptococcus faecalis
- Vibrio anguillarum
- Vibrio campbellii
- Vibrio cholerae
- Vibrio harveyi
- Vibrio mimicus
- Vibrio parahaemolyticus
- Vibrio shiloi
- Vibrio vulnificus (types 1 and 2)
- Xanthomonas campestris
- Xanthomonas axonopodis pv. citri
- Yersinia pestis[5]
https://en.wikipedia.org/wiki/Viable_but_nonculturable
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