Retention of virulence in viable but non-culturable halophilic Vibrio spp.

Baffone, Wally; Citterio, Barbara; Vittoria, Emanuela; Casaroli, A.; Campana, Raffaella; Falzano, Loredana; Donelli, Gianfranco

doi:10.1016/s0168-1605(03)00102-8

Cited by 123 publications

(85 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…A decline in culturability after long periods of incubation in sterilized water may be due either to cell death or to entry into a VBNC or an ANC state (6,30,41,77). Rahman et al (60) reported that A. hydrophila cultured in a 0.35% NaCl solution at pH 7.5 and 25°C for 50 days showed a VBNC state characterized by the presence of viable but nonculturable bacteria.…”

Section: Discussionmentioning

confidence: 99%

Behavior of an Aeromonas hydrophila aroA Live Vaccine in Water Microcosms

Vivas¹,

Carracedo²,

Riaño³

et al. 2004

Appl Environ Microbiol

View full text Add to dashboard Cite

Genetically modified auxotrophic mutants of different fish pathogens have been used as live vaccines in laboratory experiments, but the behavior of the strains after release into aquatic ecosystems has not been characterized. We previously constructed and characterized an aroA mutant of Aeromonas hydrophila and studied the protection afforded by this mutant as a live vaccine in rainbow trout. In this work, we describe the survival of this strain in aquatic microcosms prepared from fish water tanks. The aroA mutant disappeared rapidly in nonfiltered, nonautoclaved fish tank water, declining below detection levels after 15 days, suggesting an inhibitory effect of the autochthonous microflora of the water. When the aroA strain was used to inoculate sterilized water, its culturability was lower than that of wild-type strain A. hydrophila AG2; after long periods of incubation, aroA cells were able to enter a viable but nonculturable state. Entry into this nonculturable state was accompanied by changes in the cell morphology from rods to spheres, but the cells appeared to remain potentially viable, as assessed by the preservation of cell membrane integrity. Supplementation of the culture medium with sodium pyruvate favored the culturability and resuscitation of the two A. hydrophila strains at low temperatures (6 and 16°C). These results contribute to a better understanding of the behavior of the aroA strain in natural environments and suggest that the inactivation of the aroA gene may be beneficial for the safety of this live vaccine for aquacultures.

show abstract

Section: Discussionmentioning

confidence: 99%

Behavior of an Aeromonas hydrophila aroA Live Vaccine in Water Microcosms

Vivas¹,

Carracedo²,

Riaño³

et al. 2004

Appl Environ Microbiol

View full text Add to dashboard Cite

show abstract

“…In this state, although still expressing various degrees of metabolic activity and possibly being able to cause infection (6,8,9), the bacterial cells cannot be cultured on conventional laboratory media that normally support their growth. During entry into the VBNC state, bacteria acquire a coccal morphology, become smaller in size (10,11), and show changes in their protein (12,13) and fatty acid profiles (14).…”

mentioning

confidence: 99%

State transitions of Vibrio parahaemolyticus VBNC cells evaluated by flow cytometry

Falcioni

Papa

Campana

et al. 2008

Cytometry Part B Clinical

View full text Add to dashboard Cite

Background: Vibrio parahaemolyticus, in response to environmental conditions, may be present in a viable but nonculturable state (VBNC), which can still be responsible for cases of infectious diseases in humans.Methods: The characterization of the cellular states of V. parahaemolyticus during entry into, persistence in, and resuscitation from the VBNC state, was assessed through plate culture method and epifluorescence microscope evaluation of actively respiring cells. Flow cytometry (FCM) in combination with SYBR Green I (SG) and propidium iodide allowed us to distinguish between viable, dead, and damagedcells. Immunofluorescence labeling detected by FCM was used to study changes in antibody affinity.Results: Two groups of bacteria, one with High Nucleic Acid (HNA) and one having Low Nucleic Acid (LNA) content, were differentiated using SG and FCM and each was correlated with cell viability. With the aging of the microcosm, the LNA bacteria population increased while the HNA population gradually disappeared. Cytofluorimetric immunofluorescence analyses showed that the bacterial cell levels dropped from 95% at day 0 to 40% at day 26 and by day 29, antibody affinity was virtually lost. FCM analyses of light scatter signals expressed by cell population highlighted morphological changes indicating a reduction in cell size, as also shown by scanning electron microscopy images and variations in cell structure.Conclusions: The methodology used has provided useful data in relation to the state transitions of V. parahaemolyticus regarding cell viability, antigenic surface components, and the quantification of morphological variations during its entry into the VBNC state. q

show abstract

“…VBNC cells have also been shown to regain virulence after resuscitation in the human gastrointestinal tract (Sun et al, 2008;Oliver and Bockian, 1995). Baffone et al (2003) confirmed the resuscitation of VBNC V. parahaemolyticus cells in rat ileal loop assays.…”

Section: Scenario 2: Residual Rnasupporting

confidence: 60%

“…VBNC, known as "conditionally viable environmental cells (CVEC)" in some literature for V. cholerae, do not form colonies in common laboratory growth media since they are incapable of undergoing sustained cellular division, and hence, cannot be propagated using routine laboratory practices employing culturing techniques (Baffone et al, 2003;Jones et al, 2012a;Jones et al, 2012b;Oliver and Bockian, 1995;Vora et al, 2005). Under unfavorable conditions such as low temperature and low nutrients, Gram-negative bacteria were found to persist in the VBNC state, possibly as a survival mechanism (Colwell et al, 1996).…”

Section: Viable But Nonculturable (Vbnc)mentioning

confidence: 99%

“…Oliver and Bockian (1995) demonstrated that VBNC V. vulnificus retained its pathogenicity after resuscitation within 24 hours in the peritoneal cavity of mice resulting in lethality. VBNC V. parahaemolyticus and V. alginolyticus cells were inoculated intragastrically and resuscitated in rat ileal loop assays, where the cells were able to reactivate their pathogenic potential within 48 hours and to cause disease (Baffone et al, 2003). With much of the focus on virulence gene expression after resuscitation, V.…”

Section: Virulence Gene Expression In Vbnc Statementioning

confidence: 99%

See 1 more Smart Citation

Virulence gene expression of Vibrio parahaemolyticus in the viable but nonculturable state

Tse¹

View full text Add to dashboard Cite

Retention of virulence in viable but non-culturable halophilic Vibrio spp.

Cited by 123 publications

References 48 publications

Behavior of an Aeromonas hydrophila aroA Live Vaccine in Water Microcosms

Behavior of an Aeromonas hydrophila aroA Live Vaccine in Water Microcosms

State transitions of Vibrio parahaemolyticus VBNC cells evaluated by flow cytometry

Virulence gene expression of Vibrio parahaemolyticus in the viable but nonculturable state

Contact Info

Product

Resources

About