Abstract:
:Three common food pathogenic microorganisms were exposed to treatments simulating those used in food processing. Treated cell suspensions were then analyzed for reduction in growth by plate counting. Flow cytometry (FCM) and fluorescence-activated cell sorting (FACS) were carried out on treated cells stained for membrane integrity (Syto 9/propidium iodide) or the presence of membrane potential [DiOC2(3)]. For each microbial species, representative cells from various subpopulations detected by FCM were sorted onto selective and nonselective agar and evaluated for growth and recovery rates. In general, treatments giving rise to the highest reductions in counts also had the greatest effects on cell membrane integrity and membrane potential. Overall, treatments that impacted cell membrane permeability did not necessarily have a comparable effect on membrane potential. In addition, some bacterial species with extensively damaged membranes, as detected by FCM, appeared to be able to replicate and grow after sorting. Growth of sorted cells from various subpopulations was not always reflected in plate counts, and in some cases the staining protocol may have rendered cells unculturable. Optimized FCM protocols generated a greater insight into the extent of the heterogeneous bacterial population responses to food control measures than did plate counts. This study underlined the requirement to use FACS to relate various cytometric profiles generated by various staining protocols with the ability of cells to grow on microbial agar plates. Such information is a prerequisite for more-widespread adoption of FCM as a routine microbiological analytical technique.
journal_name
Appl Environ Microbioljournal_title
Applied and environmental microbiologyauthors
Kennedy D,Cronin UP,Wilkinson MGdoi
10.1128/AEM.00323-11subject
Has Abstractpub_date
2011-07-01 00:00:00pages
4657-68issue
13eissn
0099-2240issn
1098-5336pii
AEM.00323-11journal_volume
77pub_type
杂志文章abstract::The ability of the facultative photoheterotroph Rhodobacter sphaeroides to tolerate and reduce high levels of tellurite in addition to at least 10 other rare earth metal oxides and oxyanions has considerable potential for detoxification and bioremediation of contaminated environments. We report the identification and ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.63.12.4713-4720.1997
更新日期:1997-12-01 00:00:00
abstract::The filter exclusion method was used to isolate Frankia strains from Myrica pennsylvanica (bayberry) root nodules collected at diverse sites in New Jersey. A total of 16 isolates from five locations were cultured. The isolates were characterized by morphological, chemical, physiological, and plant infectivity criteria...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.55.9.2161-2166.1989
更新日期:1989-09-01 00:00:00
abstract::Cryparin is a cell-surface-associated hydrophobin of the filamentous ascomycete Cryphonectria parasitica. This protein contains a signal peptide that directs it to the vesicle-mediated secretory pathway. We detected a glycosylated form of cryparin in a secretory vesicle fraction, but secreted forms of this protein are...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.65.12.5431-5435.1999
更新日期:1999-12-01 00:00:00
abstract::Enumeration of lactic acid streptococci from dairy starter cultures on Elliker agar was improved by the addition of 0.4% (wt/vol) diammonium phosphate. Agar plate counts were up to 7.75 times greater due to improved buffering by the phosphate salt. ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.38.1.173-174.1979
更新日期:1979-07-01 00:00:00
abstract::Several variations in the scintillation mixture and the filter paper arrangements for double-vial radiorespirometry were compared. Improved efficiencies (44%) and shorter response times were found by adding wetting agents and methanolic NaOH to the scintillation mixture in the filter paper. The scintillation chemicals...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.45.1.255-259.1983
更新日期:1983-01-01 00:00:00
abstract::Aldehydes are a class of chemicals with many industrial uses. Several aldehydes are responsible for flavors and fragrances present in plants, but aldehydes are not known to accumulate in most natural microorganisms. In many cases, microbial production of aldehydes presents an attractive alternative to extraction from ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章,评审
doi:10.1128/AEM.03319-14
更新日期:2015-03-01 00:00:00
abstract::We previously reported the isolation of a 21.5-kb genomic DNA fragment from Pseudomonas sp. strain ADP, which contains the atzA gene, encoding the first metabolic step for the degradation of the herbicide atrazine (M. de Souza, L. P. Wackett, K. L. Boundy-Mills, R. T. Mandelbaum, and M. J. Sadowsky, Appl. Environ. Mic...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.63.3.916-923.1997
更新日期:1997-03-01 00:00:00
abstract::Chromohalobacter salexigens DSM 3043 can grow on N,N-dimethylglycine (DMG) as the sole C, N, and energy source and utilize sarcosine as the sole N source under aerobic conditions. However, little is known about the genes and enzymes involved in the conversion of DMG to sarcosine in this strain. In the present study, g...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.01186-20
更新日期:2020-08-18 00:00:00
abstract::A mutant of the peptide antibiotic nisin in which the dehydroalanine residue at position 5 has been replaced by an alanine has been produced and structurally characterized. It is shown to have activity very similar to that of wild-type nisin in inhibiting growth of Lactococcus lactis and Micrococcus luteus but is very...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.62.8.2966-2969.1996
更新日期:1996-08-01 00:00:00
abstract::Previous work has shown that Trametes (Coriolus) versicolor bleaches kraft pulp brownstock with the concomitant release of methanol. In this work, the fungus is shown to produce both laccase and manganese peroxidase (MnP) but not lignin peroxidase during pulp bleaching. MnP production was enhanced by the presence of p...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.59.1.260-265.1993
更新日期:1993-01-01 00:00:00
abstract::AvrPtoB is a type III effector protein from Pseudomonas syringae pv. tomato that physically interacts with the tomato Pto kinase and, depending on the host genotype, either elicits or suppresses programmed cell death associated with plant immunity. We reported previously that avrPtoB-related sequences are present in d...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.72.1.702-712.2006
更新日期:2006-01-01 00:00:00
abstract::Total DNA from 21 collection or industrial Bifidobacterium strains was cleaved with various restriction endonucleases. Following electrophoresis, the fragments were subjected to Southern blot hybridization with a heterologous [alpha-32P]dCTP-labeled rDNA (genes coding for rRNA) 23S gene probe. The ribosomal patterns a...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.60.5.1451-1458.1994
更新日期:1994-05-01 00:00:00
abstract::In this study, a number of Listeria monocytogenes strains of different origins were evaluated for in vitro invasion capacity for various human cell types (monocytic THP-1, enterocytic Caco-2, and hepatocytic HepG2 cells) and for expression levels of specific virulence genes. For THP-1 cells, no differences between cli...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02164-05
更新日期:2006-06-01 00:00:00
abstract::The ability of staphylococcal strains isolated from different anatomical sites in 133 healthy goats to produce toxic shock syndrome toxin 1 (TSST-1) and the presence of antibodies to this toxin in serum and milk were studied. The enzyme-linked immunosorbent assay method was used to detect both the toxin and the presen...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.57.3.889-891.1991
更新日期:1991-03-01 00:00:00
abstract::DNA and peptide nucleic acid (PNA) molecular beacons were successfully used to detect rRNA in solution. In addition, PNA molecular beacon hybridizations were found to be useful for the quantification of rRNA: hybridization signals increased in a linear fashion with the 16S rRNA concentrations used in this experiment (...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/aem.69.9.5673-5678.2003
更新日期:2003-09-01 00:00:00
abstract::The actinomycete Streptomyces setonii 75Vi2 demethylates vanillic acid and guaiacol to protocatechuic acid and catechol, respectively, and then metabolizes the products by the beta-ketoadipate pathway. UV spectroscopy showed that this strain could also metabolize veratrole (1,2-dimethoxybenzene). When grown in veratro...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.52.1.98-100.1986
更新日期:1986-07-01 00:00:00
abstract::A bioassay method was developed to measure the average intensity within a UV disinfection reactor. The survival of spores of Bacillus subtilis was determined as a function of UV dose to prepare a standard curve. Spores were added to unknown systems, and the survival rate was used to determine the average intensity. A ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.45.3.872-877.1983
更新日期:1983-03-01 00:00:00
abstract::The luxS gene of Lactobacillus reuteri 100-23C was amplified by PCR, cloned, and then sequenced. To define a physiological and ecological role for the luxS gene in L. reuteri 100-23C, a luxS mutant was constructed by insertional mutagenesis. The luxS mutant did not produce autoinducers AI-2 or AI-3. Complementation of...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.71.12.8419-8425.2005
更新日期:2005-12-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.54.12.3187-3190.1988
更新日期:1988-12-01 00:00:00
abstract::The oral biofilm community consists of >800 microbial species, among which Streptococcus mutans is considered a primary pathogen for dental caries. The genomic island TnSmu2 of S. mutans comprises >2% of the genome. In this study, we demonstrate that TnSmu2 harbors a gene cluster encoding nonribosomal peptide syntheta...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
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更新日期:2010-09-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.60.7.2637-2642.1994
更新日期:1994-07-01 00:00:00
abstract::A new method for the extraction of bacterial DNA from soil has been developed. Soil samples of 50 g were dispersed, and bacteria were released by use of a cation-exchange resin; subsequently, bacteria were separated from soil particles by low-speed centrifugation and lysed with lysozyme and ionic detergent, and the DN...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.58.8.2458-2462.1992
更新日期:1992-08-01 00:00:00
abstract::In this report, we describe the identification of functions that promote genomic recombination of linear DNA introduced into Pseudomonas cells by electroporation. The genes encoding these functions were identified in Pseudomonas syringae pv. syringae B728a based on similarity to the lambda Red Exo/Beta and RecET prote...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00911-10
更新日期:2010-08-01 00:00:00
abstract::The ability of microorganisms to perform dissimilatory (per)chlorate reduction is, for most species, known to be oxygen sensitive. Consequently, bioremediation processes for the removal of oxochlorates will be disturbed if oxygen is present. We measured the expression of chlorite dismutase and chlorate reductase in th...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.07303-11
更新日期:2012-06-01 00:00:00
abstract::Two methods were used to evaluate bacterial recovery from beef, pork, and lamb adipose tissue. Higher counts were obtained with a tissue removal and fluid agitation technique (shaking) than with surface swabbing, but only when bacterial levels were low. Bacterial recovery by both methods was unaffected by specie origi...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.35.5.978-979.1978
更新日期:1978-05-01 00:00:00
abstract::Freshwater, sewage, and fecal samples from various sources were examined for Rhodococcus coprophilus, associated actinomycetes, Escherichia coli, and fecal streptococci. Rhodococcus coprophilus was isolated consistently from feces of farm animals, poultry reared in proximity to farm animals, freshwater, and wastewater...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.42.6.1037-1042.1981
更新日期:1981-12-01 00:00:00
abstract::We used global transcript analyses and mutant studies to investigate the pathways that impact H(2) production in the photosynthetic bacterium Rhodobacter sphaeroides. We found that H(2) production capacity is related to the levels of expression of the nitrogenase and hydrogenase enzymes and the enzymes of the Calvin-B...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.05273-11
更新日期:2011-10-01 00:00:00
abstract::Trehalose accumulation is a common cell defense strategy against a variety of stressful conditions. In particular, our team detected high levels of trehalose in Propionibacterium freudenreichii in response to acid stress, a result that led to the idea that endowing Lactococcus lactis with the capacity to synthesize tr...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02922-10
更新日期:2011-06-01 00:00:00
abstract::Differences in biological activities (hemagglutination, hemolytic, leukotoxic, and virulence) and ribotypes between the two subspecies of Fusobacterium necrophorum of bovine ruminal and liver abscess origins were investigated. Hemagglutination activity was present in all hepatic, but only some ruminal, strains of Fuso...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.62.2.469-472.1996
更新日期:1996-02-01 00:00:00
abstract::Small-subunit ribosomal DNA (SSU rDNA) from 20 phenotypically distinct strains of 2,4-dichlorophenoxyacetic acid (2,4-D)-degrading bacteria was partially sequenced, yielding 18 unique strains belonging to members of the alpha, beta, and gamma subgroups of the class Proteobacteria. To understand the origin of 2,4-D deg...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.64.10.4089-4092.1998
更新日期:1998-10-01 00:00:00