Psychrotrophic Strain ofJanthinobacterium lividumfrom a Cold Alaskan Soil Produces Prodigiosin

ABSTRACT The 11-kb sequence encompassing the alkylbenzene upper pathway inPseudomonas putida 01G3, a psychrotrophic strain able to degrade alkylbenzenes at low temperatures, was characterized. Together with a potential regulator (EbdR), six putative enzymes (EbdAaAbAcAdBC) were identified, and they exhibited highly significant similarities with enzymes implicated in the equivalent pathway in P. putida RE204. ebd genes appeared to be preferentially induced by ethylbenzene. Multiple-alignment data and growth rate measurements led us to classify 01G3 and closely related strains in two groups with distinct substrate specificities. Close to identified genes, remnants of IS5-like elements provided insight into the evolution of catabolic sequences through rearrangements from a less complex ancestral cluster.

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Comparative study of 7 fluorescent pseudomonad clinical isolates

Canadian Journal of Microbiology ◽

10.1139/w07-110 ◽

2008 ◽

Vol 54 (1) ◽

pp. 19-27 ◽

Cited By ~ 29

Author(s):

A. Chapalain ◽

G. Rossignol ◽

O. Lesouhaitier ◽

A. Merieau ◽

C. Gruffaz ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Comparative Study ◽

Glial Cells ◽

Potential Range ◽

Cytotoxic Activities ◽

Fluorescent Pseudomonad ◽

Clinical Strains ◽

Infectious Form ◽

Psychrotrophic Strain ◽

Infectious Potential

There is some debate about the potential survival of Pseudomonas fluorescens at temperatures above 37 °C and its consequences for infectious potential, owing to the heterogeneity of clinical strains. Seven clinical strains growing at 37 °C or more were submitted for polyphasic identification; 2 were identified as Pseudomonas mosselii and 4 were precisely characterized as P. fluorescens bv. I or II. The binding indexes on glial cells of the strains identified as P. fluorescens bv. I and P. mosselii were compared with that of a reference psychrotrophic strain, P. fluorescens MF37 (bv. V). Clinical P. fluorescens had a similar adherence potential range than strain MF37. Conversely, the binding indexes for P. mosselii strains were 3 times greater than that for strain MF37. These data, and those obtained by comparing the cytotoxic activities of P. fluorescens clinical strains, suggest the existence of different virulence mechanisms, leading either to a low infectious form or to a microorganism with cytotoxic activity in the same range as that of P. mosselii or even Pseudomonas aeruginosa .

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Growth and Survival of Listeria monocytogenes in Vacuum-Packaged Ground Beef Inoculated with Lactobacillus alimentarius FloraCarn L-2

Journal of Food Protection ◽

10.4315/0362-028x-61.5.551 ◽

1998 ◽

Vol 61 (5) ◽

pp. 551-556 ◽

Cited By ~ 32

Author(s):

BENJAMIN J. JUVEN ◽

SUSAN F. BAREFOOT ◽

MERLE D. PIERSON ◽

LINDA H. McCASKILL ◽

BRIAN SMITH

Keyword(s):

Hydrogen Peroxide ◽

Lactic Acid ◽

Listeria Monocytogenes ◽

Ground Beef ◽

Resistant Mutant ◽

Antibiotic Resistant ◽

Growth And Survival ◽

Ca 50 ◽

Psychrotrophic Strain

A culture of the psychrotrophic strain FloraCarn L-2 of Lactobacillus alimentarius was added to ground beef (pH 5.4) inoculated with two isolates of Listeria monocytogenes able to grow in refrigerated ground beef. The ground beef was vacuum-packaged and stored for 9 weeks at 4°C. Populations of inoculated L. monocytogenes initially were 6.3 to 6.4 log10 CFU/g and increased to 7.4 log10 CFU/g in ground beef with no added lactobacilli. Addition of L. alimentarius L-2 or its antibiotic-resistant mutant SRL-2 reduced the final populations of L. monocytogenes to 4.3 or 4.1 log10 CFU/g, respectively. L. alimentarius L-2 did not produce bacteriocins or hydrogen peroxide in vitro. The antilisterial effect of L. alimentarius observed in laboratory media and ground beef is attiibuted to lactic acid (ca. 50 mM) produced by growing cultures.

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CspB and CspC are induced upon cold shock in Bacillus cereus strain D2

Canadian Journal of Microbiology ◽

10.1139/cjm-2021-0025 ◽

2021 ◽

Author(s):

Haoyang Li ◽

Rui Yang ◽

Linlin Hao ◽

Chunli Wang ◽

Mingtang Li

Keyword(s):

Bacillus Cereus ◽

Contaminated Soils ◽

Cold Shock ◽

Amino Acid Sequences ◽

Cold Shock Protein ◽

E Coli ◽

Subsequent Transformation ◽

Cold Shock Response ◽

Shock Response ◽

Psychrotrophic Strain

Bacillus cereus D2, a psychrotrophic strain, plays an essential role in the restoration of heavy metal-contaminated soils, especially at low temperatures. However, the cold shock response mechanisms of this strain are unclear. In this study, the cold shock response of B. cereus D2 was characterized; as per the Arrhenius curve, 10 °C was chosen as the cold shock temperature. Six cold shock-like proteins were found and temporarily named cold shock protein (Csp)1-6; the respective genes were cloned and identified. Quantitative real-time PCR results showed that csp1, csp2, csp3, and csp6 were overexpressed under cold shock conditions. Interestingly, after cloning the respective encoding genes into pET-28a (+) vector and their subsequent transformation into E. coli BL21 (DE3), the strains expressing Csp2 and Csp6 grew faster at 10 °C, showing a large number of bacteria. These results suggest that Csp2 and Csp6 are the major cold shock proteins in B. cereus D2. Of note, the comparison of amino acid sequences and structures showed that Csp2 and Csp6 belong to the CspB and CspC families, respectively. Additionally, we show that the number of hydrophobic residues is not a determining feature of major Csps, while, on the other hand, the formation of an α-helix in the context of a leucine residue is the most dominant difference between major, and other Bacillus and E. coli Csps.

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Survival stages of a psychrotrophic Cytophaga johnsonae strain

Canadian Journal of Microbiology ◽

10.1139/m82-126 ◽

1982 ◽

Vol 28 (7) ◽

pp. 841-850 ◽

Cited By ~ 7

Author(s):

Wolfgang Reichardt ◽

Richard Y. Morita

Keyword(s):

Incubation Temperature ◽

Intermediate Stage ◽

Mineral Salts ◽

Protein Ratio ◽

Glucose Incorporation ◽

The Common ◽

Murein Sacculus ◽

Cellular Dna ◽

Psychrotrophic Strain ◽

Substrate Affinities

Cells of a psychrotrophic strain of Cytophaga johnsonae, when exposed to starvation in a mineral salts medium, produced short viable rods, viable coccoids, and moribund elongated cells as a function of the incubation temperature. Starvation for 14 days or longer resulted in an increase of the cellular DNA to protein ratio. While rod-shaped cells possessed an intermediate layer identified as murein sacculus, coccoid cells displayed the common properties of spheroplasts, and their formation was frequently preceded by a pestlelike intermediate stage. During survival, substrate affinities (1/Km) for transport, respiration, and incorporation of glucose increased in both rod and coccoid cells. The rods appeared to possess dual, concentration-dependent metabolic pathways for glucose. Glucose incorporation by starved cells into macromolecular pools had lower Km values (10 to 203 times lower) than the values found for exponentially growing and nonviable rods. Coccoid cells demonstrated a slightly increased resistance to mild heat stress compared with log phase cells but were equally susceptible to ultrasonic vibration and ultraviolet irradiation. The data obtained indicated that unbalanced cellular divisions of multinucleate cells at low temperature and starvation result in coccoid cells. The coccoid cells are probably the survival forms in nature when low temperatures and nutrient deprivation exist.

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Genome Sequence of Oenococcus oeni UNQOe19, the First Fully Assembled Genome Sequence of a Patagonian Psychrotrophic Oenological Strain

Microbiology Resource Announcements ◽

10.1128/mra.00889-18 ◽

2018 ◽

Vol 7 (5) ◽

Cited By ~ 3

Author(s):

Néstor G. Iglesias ◽

Danay Valdés La Hens ◽

Nair T. Olguin ◽

Bárbara M. Bravo-Ferrada ◽

Natalia S. Brizuela ◽

...

Keyword(s):

Genome Sequence ◽

Malolactic Fermentation ◽

Oenococcus Oeni ◽

Pinot Noir ◽

Native Strain ◽

Content Type ◽

Psychrotrophic Strain

Oenococcus oeni UNQOe19 is a native strain isolated from a Patagonian pinot noir wine undergoing spontaneous malolactic fermentation. Here, we present the 1.83-Mb genome sequence of O. oeni UNQOe19, the first fully assembled genome sequence of a psychrotrophic strain from an Argentinean wine.

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α-Glucosidase and β-glucosidase from psychrotrophic strain arthrobacter sp. C2-2

Czech Journal of Food Sciences ◽

10.17221/3380-cjfs ◽

2011 ◽

Vol 23 (No. 3) ◽

pp. 116-120 ◽

Cited By ~ 9

Author(s):

E. Benešová ◽

M. Marková ◽

B. Králová

Keyword(s):

Exchange Chromatography ◽

Gel Chromatography ◽

Bacterial Strains ◽

Molecular Weights ◽

Ammonium Sulphate Precipitation ◽

Donor And Acceptor ◽

Alpha Galactosidase ◽

Beta Glucosidase ◽

Psychrotrophic Strain ◽

Alpha Glucosidase

In this work six psychophilic and psychrotrophic bacterial strains were screened for the presence of different glycosidase activities (α-galactosidase, α-glucosidase, β-glucosidase, α-mannosidase and β-glucuronidase). Nine enzymes were found and their elementary characteristics were measured (toptimum, pHoptimum, Km, Vlim).Two enzymes with the highest activities at low temperatures were chosen for the next study, i.e. α-glucosidase and β-glucosidase from the psychrotrophic strain Arthrobacter sp. C2-2. These enzymes were purified by ammonium sulphate precipitation, by chromatography with hydrophobic interaction, and by ion-exchange chromatography. Their molecular weights (α-glucosidase – 76 kDa, β-glucosidase – 93 kDa) were determined by gel chromatography. In addition to this, it was verified that both of these enzymes are able to catalyse the transglycosylation reaction with the saccharidic donor and acceptor.

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Predictive Modeling of Psychrotrophic Bacillus cereus

Journal of Food Protection ◽

10.4315/0362-028x-56.8.684 ◽

1993 ◽

Vol 56 (8) ◽

pp. 684-688 ◽

Cited By ~ 28

Author(s):

JANICE M. BAKER ◽

MANSEL W. GRIFFITHS

Keyword(s):

Bacillus Cereus ◽

Response Surface ◽

Water Activity ◽

Brain Heart Infusion ◽

Toxin Production ◽

Plate Counts ◽

Toxin Assay ◽

Predicted Values ◽

Experimental Values ◽

Psychrotrophic Strain

Response surface analysis was used to determine the effects and interactions of water activity (0.965 to 0.995), pH (5.8 to 8.0), temperature (6 to 38°C), glucose concentration (0 to 1.8%), and starch concentration (0 to 0.625%) on the growth of and toxin production by a psychrotrophic strain of Bacillus cereus in brain heart infusion broth. Growth was measured by monitoring optical density and plate counts, toxin production was assayed by an immunological method (BCET-RPLA toxin assay) and cytotoxicity with Vero and HEp-2 cells. Regressions were performed using response surface techniques, on Growth, LnGrowth, RPLA, LnRPLA, Vero, LnVero, and HEp-2; quadratic predictive equations for growth and toxin production were obtained. The results indicate the factors that had the greatest influence on both growth and toxin production were water activity and temperature. Predicted values obtained from the model were in good agreement with experimental values.

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Pore Size Dependence on Growth Temperature Is a Common Characteristic of the Major Outer Membrane Protein OprF in Psychrotrophic and Mesophilic Pseudomonas Species

Applied and Environmental Microbiology ◽

10.1128/aem.70.11.6665-6669.2004 ◽

2004 ◽

Vol 70 (11) ◽

pp. 6665-6669 ◽

Cited By ~ 29

Author(s):

Thomas Jaouen ◽

Emmanuelle DÃ¯Â¿Â½ ◽

Sylvie Chevalier ◽

Nicole Orange

Keyword(s):

Membrane Permeability ◽

Outer Membrane ◽

Lipid Bilayers ◽

Growth Temperature ◽

Outer Membrane Proteins ◽

Ecological Niches ◽

Rich Cluster ◽

Channel Size ◽

Outer Membrane Permeability ◽

Psychrotrophic Strain

ABSTRACT Pseudomonas species adapt well to hostile environments, which are often subjected to rapid variations. In these bacteria, the outer membrane plays an important role in the sensing of environmental conditions such as temperature. In previous studies, it has been shown that in the psychrotrophic strain P. fluorescens MF0, the major porin OprF changes its channel size according to the growth conditions and could affect outer membrane permeability. Studies of the channel-forming properties of OprFs from P. putida 01G3 and P. aeruginosa PAO1 in planar lipid bilayers generated similar results. The presence of a cysteine- or proline-rich cluster in the central linker region is not essential for channel size modulations. These findings suggest that OprF could adopt two alternative conformations in the outer membrane and that folding is thermoregulated. In contrast, no difference according to growth temperature was observed for structurally different outer membrane proteins, such as OprE3 from the Pseudomonas OprD family of specific porins. Our results are consistent with the fact that the decrease in channel size observed at low growth temperature is a particular feature of the OprF porin in various psychrotrophic and mesophilic Pseudomonas species isolated from diverse ecological niches. The ability to reduce outer membrane permeability at low growth temperature could provide these bacteria with adaptive advantages.

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