The effect of compounds which degrade hydrogen peroxide on the enumeration of heat-stressed cells of <i>Salmonella senftenberg</i>

Rayman, M. K.; Aris, B.; Derea, H. B. El

doi:10.1139/m78-146

Cited by 51 publications

(41 citation statements)

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“…Catalase addition did not affect the culturability of untreated cells. Furthermore, the addition of sodium pyruvate, a compound that degrades H 2 O 2 (28,30,38), to the surfaces of LB agar plates also increased the number of CFU obtained from TCE-treated cells (data not shown).…”

Section: Resultsmentioning

confidence: 96%

“…From studies performed primarily within the context of food microbiology and public health, it is known that catalase and pyruvate can increase the enumeration of physically or chemically injured bacteria on agar plates (5,28,30). It is thought that catalase and pyruvate act by preventing the accumulation of H 2 O 2 in and/or around injured cells, which, in contrast to healthy cells, are apparently unable to tolerate even low levels of this reactive oxygen species (28,38). In this study, we found that the addition of catalase or sodium pyruvate to the surfaces of the LB agar plates increased the culturability of TCE-treated cells of B. cepacia G4 by as much as 100-fold.…”

Section: Discussionmentioning

confidence: 99%

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Cytotoxicity Associated with Trichloroethylene Oxidation in Burkholderia cepacia G4

Yeager¹,

Bottomley

Arp

2001

Appl Environ Microbiol

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The effects of trichloroethylene (TCE) oxidation on toluene 2-monooxygenase activity, general respiratory activity, and cell culturability were examined in the toluene-oxidizing bacterium Burkholderia cepacia G4. Nonspecific damage outpaced inactivation of toluene 2-monooxygenase in B. cepacia G4 cells. Cells that had degraded approximately 0.5 mol of TCE (mg of cells ؊1 ) lost 95% of their acetate-dependent O 2 uptake activity (a measure of general respiratory activity), yet toluene-dependent O 2 uptake activity decreased only 35%. Cell culturability also decreased upon TCE oxidation; however, the extent of loss varied greatly (up to 3 orders of magnitude) with the method of assessment. Addition of catalase or sodium pyruvate to the surfaces of agar plates increased enumeration of TCE-injured cells by as much as 100-fold, indicating that the TCE-injured cells were ultrasensitive to oxidative stress. Cell suspensions that had oxidized TCE recovered the ability to grow in liquid minimal medium containing lactate or phenol, but recovery was delayed substantially when TCE degradation approached 0.5 mol (mg of cells ), up to 90% were Tol ؊ variants, no longer capable of TCE degradation. These results indicate that a toxicity threshold for TCE oxidation exists in B. cepacia G4 and that once a cell suspension has exceeded this toxicity threshold, the likelihood of reestablishing an active, TCE-degrading biomass from the cells will decrease significantly.Trichloroethylene (TCE), a suspected human carcinogen, is one of the most widespread groundwater contaminants. Although TCE can be reductively dehalogenated under anaerobic conditions, a common end product of this reaction is vinyl chloride, which is more water soluble than TCE and is a known human carcinogen (4, 21, 48). Removal of TCE from polluted sites or industrial discharge is therefore of great concern. Although TCE has not been shown to support microbial growth under aerobic conditions, a number of bacteria are capable of degrading this compound via aerobic cometabolism. In each case examined to date, a nonspecific oxygenase catalyzes TCE transformation. Bacterial strains that use oxygenases to grow on methane, butane, propene, ethylene, ammonia, toluene, phenol, isoprene, and dichlorophenoxyacetic acid have been characterized as TCE degraders (3,8,10,11,17,18,39,45,54). Although some of these bacteria exhibit high initial rates of TCE conversion, the process is invariably nonsustainable in the absence of a growth-supporting substrate (2,19,35,49).From the biological standpoint, aerobic cometabolism of TCE by microorganisms is largely dependent on two factors: (i) cellular energy requirements and (ii) the toxicity often associated with TCE oxidation. Energy problems can be overcome by carefully controlling the concentrations of the cometabolite and growth substrate (6, 9) or by selecting or designing microorganisms that are capable of expressing the TCE-degrading oxygenase while growing on a noncompetitive substrate (29,32,41). Perhaps more problematic is the t...

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Section: Resultsmentioning

confidence: 96%

Section: Discussionmentioning

confidence: 99%

Cytotoxicity Associated with Trichloroethylene Oxidation in Burkholderia cepacia G4

Yeager¹,

Bottomley

Arp

2001

Appl Environ Microbiol

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“…Since one known effect of sodium pyruvate on microbiological media is to degrade hydrogen peroxide (3,7,14,16,17,18,29), the possibility that a hydrogen peroxide-sensitive population of culturable cells had formed in the cold ASW was investigated. Catalase, an enzyme which breaks down hydrogen peroxide, was added to HI plates by surface spreading.…”

Section: Resultsmentioning

confidence: 99%

“…A plating assay revealed that the culturable cells from middle time points in the studies were much more sensitive to hydrogen peroxide than fresh HI broth-derived cells. Supplementation of HI plates with either sodium pyruvate or catalase, agents which degrade hydrogen peroxide (3,7,14,16,17,18,29), yielded higher colony counts. However, there was also a continued decline to complete loss of these culturable cells (Fig.…”

Section: Discussionmentioning

confidence: 98%

“…Injury in bacteria has been defined by respected workers in the field, such as Speck and McFeters, as an increased sensitivity to components of growth media which are not normally inhibitory (11,19,20,27,28,30,31); the injured state is transient, resulting from cumulative damage, and death in bacteria has been defined by these workers as the point "where injury extends beyond the ability of a cell to multiply and form a colony" (28,31). Amendment of plate count media with catalase or sodium pyruvate has long been employed as a means to recover injured bacterial cells (3,7,14,16,17,18,29). It could be argued that our results support the VBNC hypothesis, in that the cells have entered a state in which they are viable but nonculturable on HI plates.…”

Section: Discussionmentioning

confidence: 99%

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Recovery of Hydrogen Peroxide-Sensitive Culturable Cells of Vibrio vulnificus Gives the Appearance of Resuscitation from a Viable but Nonculturable State

et al. 2000

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The viabilities of five strains of Vibrio vulnificus were evaluated during the storage of the organisms in sterile seawater at 5°C. The number of CFU was measured by plate count methods on rich media. The total cell numbers were determined by direct microscopic count methods. The titer of CFU declined logarithmically to undetectable levels over a period of 2 to 3 weeks, while the total cell numbers were unchanged. Midway through each study, higher culturable cell counts began to be observed on plates containing catalase or sodium pyruvate; during the latter stages of the study, the plate counts on such media were up to 1,000-fold higher than those on unsupplemented plates. Because autoclaving is known to generate hydrogen peroxide in rich media, and because catalase and sodium pyruvate are known to eliminate hydrogen peroxide, it appears that the conditions of the experiments led to the selection of a hydrogen peroxide-sensitive culturable cell subpopulation. At the time of the final stage of the decline in viability of each culture, hydrogen peroxide-sensitive cells were the only culturable cells present. Warming samples of the cultures to room temperature led to the growth of these residual culturable cells, utilizing nutrients provided by the nonculturable cells. The cells that grew recovered hydrogen peroxide resistance. When mixtures of culturable and nonculturable cells were diluted to the point where only nonculturable cells were present, or when the hydrogen peroxide-sensitive culturable cells had declined to undetectable levels, warming had no effect; no culturable cells were recovered. Warming has been reported to "resuscitate" nonculturable cells. Recognition of the existence of hydrogen peroxide-sensitive culturable cell populations, as well as their ability to grow to high levels in the warmed seawater microcosms, leads instead to the conclusion that while warming permits culturable cells to grow, it has no effect on nonculturable cells.

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Differential Resuscitative Effects of Pyruvate and Its Analogs on VBNC (Viable But Nonculturable) Salmonella

Amano

2016

Stress and Environmental Regulation of Gene Expression and Adaptation in Bacteria

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The effect of compounds which degrade hydrogen peroxide on the enumeration of heat-stressed cells of Salmonella senftenberg

Cited by 51 publications

References 0 publications

Cytotoxicity Associated with Trichloroethylene Oxidation in Burkholderia cepacia G4

Cytotoxicity Associated with Trichloroethylene Oxidation in Burkholderia cepacia G4

Recovery of Hydrogen Peroxide-Sensitive Culturable Cells of Vibrio vulnificus Gives the Appearance of Resuscitation from a Viable but Nonculturable State

Differential Resuscitative Effects of Pyruvate and Its Analogs on VBNC (Viable But Nonculturable) Salmonella

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