Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0009443 (cold)
 92,137 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The activities of isocitrate lyase, esterase, and lipase by the psychrotrophic Acinetobacter sp. strain HH1-1 were monitored during incubation at 25 degreesC, 5 degreesC, and after a 25 degreesC to 5 degreesC down shift in growth temperature. During growth at 25 degreesC, isocitrate lyase activity was detected in cell-free extracts, but at 5 degreesC and after cold shock, activity was measured primarily in the cell culture supernatant. Strain HH1-1 produced two cell-associated esterases and an extracellular esterase and lipase. Activities of the extracellular esterase and lipase were reduced when cells were grown at 5 degreesC and after cold shock. In contrast, an increased synthesis of a 53-kDa cell-associated esterase was observed 50 h after cold shock. An extracellular polysaccharide was also produced, indicated by a decrease in surface tension in cell culture supernatant when cells were incubated at 25 degreesC; but like extracellular enzyme activity, production of the exopolymer was reduced when cells were subjected to low temperatures. These results indicated that the intracellular enzyme, isocitrate lyase, leaked out of the cell after cold shock and during growth at 5 degreesC. The increased activity of a cell-associated esterase suggested this enzyme is required for growth at low temperatures. In contrast, activities of extracellular lipolytic enzymes and production of an extracellular polysaccharide were negatively affected at the lower temperatures.
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PMID:Effects of low temperature, cold shock, and various carbon sources on esterase and lipase activities and exopolysaccharide production by a psychrotrophic Acinetobacter sp. 1131 10

An Antarctic marine bacterium (strain 116) excreting an extracellular cold-adapted metalloprotease was subjected to a detailed polyphasic taxonomic investigation. Strain 116 was previously isolated from the stomach of a specimen of the Antarctic krill Euphasia superba Dana and tentatively characterized as Sphingomonas paucimobilis 116. The 16S rDNA sequence analysis showed that the strain is in fact related to species of the genus Psychrobacter, next to Psychrobacter glacincola (97.4% similarity). Sequence similarities between strain 116 and other Psychrobacter species ranged from 96.9% (with P. urativorans) to 95.4% (with P. immobilis). Key phenotypic characteristics as well as chemotaxonomic features of the bacterium were congruent with the description of the genus Psychrobacter i.e. cells were strictly aerobic, strongly oxidase-positive, psychrotrophic, halotolerant, gram-negative non-motile coccobacilli, with ubiquinone-8 as the main respiratory lipoquinone and 18:1 cis 9, 16:1 cis and 17:1 (omega8c being the predominant cellular fatty acids. The G+C content of the DNA was 43.6 mol%. DNA-DNA hybridization studies showed that the relatedness between strain 116 and Psychrobacter glacinola is only 62.2%. Further differences were apparent in whole-cell SDS-PAGE protein pattern, cellular fatty acid profile and in a number of physiological and biochemical characteristics as well as in enzymatic activities. Tolerance to 5% bile salts, nitrate reduction, citrate utilization, acid production from carbohydrates, alkaline phosphatase, acid phosphatase, C4 esterase, C14 lipase and valine arylamidase were found to differentiate strain 116 from Psychrobacter glacincola. On the basis of this phenotypic and molecular evidences, strain 116, previously known as Sphingomonas paucimobilis 116, was recognized as a new species of the genus Psychrobacter for which the name Psychrobacter proteolyticus is proposed. Strain 116 has been deposited in the Collection de l'Institut Pasteur, France, as CIP106830T and in the Deutsche Sammlung von Mikroorganismen and Zellkulturen, as DSM13887.
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PMID:Psychrobacter proteolyticus sp. nov., a psychrotrophic, halotolerant bacterium isolated from the Antarctic krill Euphausia superba Dana, excreting a cold-adapted metalloprotease. 1140 98

We have previously reported that a psychrotrophic bacterium, Pseudomonas sp. strain KB700A, which displays sigmoidal growth even at -5 degrees C, produced a lipase. A genomic DNA library of strain KB700A was introduced into Escherichia coli TG1, and screening on tributyrin-containing agar plates led to the isolation of the lipase gene. Sequence analysis revealed an open reading frame (KB-lip) consisting of 1,422 nucleotides that encoded a protein (KB-Lip) of 474 amino acids with a molecular mass of 49,924 Da. KB-Lip showed 90% identity with the lipase from Pseudomonas fluorescens and was found to be a member of Subfamily I.3 lipase. Gene expression and purification of the recombinant protein were performed. KB-Lip displayed high lipase activity in the presence of Ca2+. Addition of EDTA completely abolished lipase activity, indicating that KB-Lip was a Ca2+-dependent lipase. Addition of Mn2+ and Sr2+ also led to enhancement of lipase activity but to a much lower extent than that produced by Ca2+. The optimal pH of KB-Lip was 8 to 8.5. The addition of detergents enhanced the enzyme activity. When p-nitrophenyl esters and triglyceride substrates of various chain-lengths were examined, the lipase displayed highest activity towards C10 acyl groups. We also determined the positional specificity and found that the activity was 20-fold higher toward the 1(3) position than toward the 2 position. The optimal temperature for KB-Lip was 35 degrees C, lower than that for any previously reported Subfamily I.3 lipase. The enzyme was also thermolabile compared to these lipases. Furthermore, KB-Lip displayed higher levels of activity at low temperatures than did other enzymes from Subfamily I.3, indicating that KB-Lip has evolved to function in cold environments, in accordance with the temperature range for growth of its psychrotrophic host, strain KB700A.
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PMID:Low-temperature lipase from psychrotrophic Pseudomonas sp. strain KB700A. 1152 6

Heat shock proteins (HSPs) are cytoprotective proteins that are expressed constitutively and/or at elevated levels upon the exposure of cells to stress. The aim of this study was to investigate the potential effects of HSP preinduction by cold- (CWI) or hot-water immersion (HWI) on pro-inflammatory cytokine production (IL-1, IL-6, TNF-alpha) in cholecystokinin-octapeptide(CCK)-induced acute pancreatitis. Rats were injected with 3 x 75 microg/kg CCK subcutaneously at intervals of 2 h at the peak level of HSP synthesis, as determined by Western blot analysis. The animals were killed by exsanguination through the abdominal aorta 2 h after the last CCK injection. The serum IL-1, IL-6, TNF-alpha, and amylase levels, the pancreatic weight/body weight ratio, and the pancreatic contents of DNA, protein, amylase, lipase and trypsinogen were measured; biopsy for histology was taken. HWI significantly elevated the HSP72 expression, while CWI significantly increased the HSP60 expression. HWI pretreatment decreased all of the measured serum cytokine levels in this acute pancreatitis model. CWI and HWI pretreatment ameliorated most of the examined laboratory and morphological parameters of CCK-induced pancreatitis. The findings suggest the possible roles of HSP60 and HSP72 in the protection against CCK-induced pancreatitis. HSP72 might also participate in the reduction of pro-inflammatory cytokine synthesis.
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PMID:Water immersion pretreatment decreases pro-inflammatory cytokine production in cholecystokinin-octapeptide-induced acute pancreatitis in rats: possible role of HSP72. 1171 68

A recombinant lipase cloned from Pseudomonas fragi strain IFO 3458 (PFL) was found to retain significant activity at low temperature. In an attempt to elucidate the structural basis of this behaviour, a model of its three-dimensional structure was built by homology and compared with homologous mesophilic lipases, i.e. the Pseudomonas aeruginosa lipase (45% sequence identity) and Burkholderia cepacia lipase (38%). In this model, features common to all known lipases have been identified, such as the catalytic triad (S83, D238 and H260) and the oxyanion hole (L17, Q84). Structural modifications recurrent in cold-adaptation, i.e. a large amount of charged residues exposed at the protein surface, have been detected. Noteworthy is the lack of a disulphide bridge conserved in homologous Pseudomonas lipases that may contribute to increased conformational flexibility of the cold-active enzyme.
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PMID:The cold-active lipase of Pseudomonas fragi. Heterologous expression, biochemical characterization and molecular modeling. 1208 74

Heat shock proteins (HSPs) are necessary in the synthesis, degradation, folding, transport, and translocation of different proteins. It is well known that the increased expression of HSPs may have a protective effect against cerulein-induced pancreatitis in rats or against choline-deficient ethionine-supplemented diet model pancreatitis in mice. The aim of this study was to investigate the potential effects of HSP preinduction by cold or hot water immersion on trypsin-induced acute pancreatitis in rats. Trypsin was injected into the interlobular tissue of the duodenal part of the pancreas at the peak level of HSP synthesis, as determined by Western blot analysis. The rats were sacrificed by exsanguination through the abdominal aorta 6 h after the trypsin injection. The serum amylase activity, the tumor necrosis factor-alpha, interleukin-1, and interleukin-6 levels, the pancreatic weight/body weight ratio, and the pancreatic contents of DNA, protein, amylase, lipase, and trypsinogen were measured. A biopsy for histology was taken. Hot water immersion significantly elevated the HSP72 expression, while cold water immersion significantly increased the HSP60 expression. Cold water immersion pretreatment ameliorated the pancreatic edema in trypsin-induced pancreatitis, however this was not due to the HSP60. Hot water immersion pretreatment did not have any effect on the measured parameters in trypsin-induced pancreatitis. The findings suggest that the induction of HSP60 or HSP72 are not enough to protect rats against the early phase of this localized necrohemorrhagic pancreatitis model.
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PMID:Induction of heat shock proteins fails to produce protection against trypsin-induced acute pancreatitis in rats. 1214 32

A seasonal study of the quantitative and qualitative distribution of heterotrophic bacterial community was carried out in the Adriatic Sea between April 1995 and January 1996, in order to evaluate its spatial and temporal variability and metabolic potential in the degradation processes of organic matter. The culturable bacteria (CFU) ranged between 0.1 and 22% of total bacterioplankton with a maximum percentage in surface samples of coastal zones. Their distribution was generally affected by the prevailing hydrological conditions. At the coastal stations about 44-75% of CFU variance could be explained by river runoff. The changes in the composition of heterotrophic bacterial community showed a seasonal succession of main bacterial groups, with a prevalence of Gram negative, non fermenting bacteria in the cold period (April-January) and an increase of Vibrionaccae and pigmented bacteria in summer. The seasonal variations were more important at the stations influenced by rivers than offshore. The bacterial community showed a greater versatility for organic polymers hydrolysis in the offshore station than in the coastal areas. Over 60% of all isolated heterotrophic bacteria expressed peptidase, lipase and phosphatase ectoenzymes activities, in all seasons and showed an increasing trend in warm period (in July October). The alpha- and beta-glucosidase potentials of bacteria were lower (20% on average) and showed different pattern during the year. These results suggest different role of the bacterial community in the decomposition of organic matter in the Adriatic Sea. Since only 20% of bacterial strains expressed glucosidase activity, carbohydrate-rich polymers such as mucilage might accumulate.
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PMID:Heterotrophic bacteria in the northern Adriatic Sea: seasonal changes and ectoenzyme profile. 1214 42

The reason for the reported difference in spoilage behaviour of skim and whole pasteurised milks was investigated. The rates of growth of psychrotrophic bacteria were not significantly different in the two milks and the bacterial types, all pseudomonads, present at spoilage were also similar. However, when representative spoilage organisms were cultured into freshly pasteurised skim and whole milks, skim milks exhibited predominantly bitter flavours while whole milk showed mostly sour flavours. The different spoilage behaviours can be largely explained by greater proteolvsis in skim milk than in whole milk, caused by higher production of protease and greater susceptibility of the protein to protease attack. In addition, lipolysis in whole milk, caused by the substantial quantities of lipase produced by spoilage pseudomonads in this milk, also contributes to the different flavours produced during cold storage of these milk types.
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PMID:Spoilage patterns of skim and whole milks. 1222 1

We cloned a gene coding for a cold-active esterase from a genomic library of Acinetobacter sp. strain No. 6, a psychrotroph isolated from Siberian soil. The gene, aest, encoded a protein of 301 amino acid residues, the deduced sequence of which had less than 17% identity to sequences of known esterases and lipases. However, the esterase seemed to belong to the alpha/beta hydrolase superfamily, because it contained a sequence, Gly-Xaa-Ser-Xaa-Gly (with Xaa an arbitrary amino acid residue), found in most serine hydrolases of this superfamily. Sequence comparison earlier suggested a weak phylogenetic relationship of gene product AEST to the EST group of the esterase-lipase family, which has been found only in eukaryotes. The aest gene was expressed in Escherichia coli BL21(DE3) cells under the control of the T7 promoter, and the expression product was purified to homogeneity and characterized. It catalyzed the hydrolysis of esters with short-chain acyl groups and had lower activation energy and lower thermostability than do mesophilic enzymes, as expected from the cold-adapted nature of this enzyme.
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PMID:Primary structure and catalytic properties of a cold-active esterase from a psychrotroph, Acinetobacter sp. strain No. 6. isolated from Siberian soil. 1235 28

Serratia marcescens isolated from raw milk was found to produce extracellular lipase. The growth of this organism could contribute to flavor defects in milk and dairy products. Serratia marcescens was streaked onto spirit blue agar medium, and lipolytic activity was detected after 6 h at 30 degrees C and after 12 h at 6 degrees C. The extracellular crude lipase was collected after inoculation of the organism into nutrient broth and then into skim milk. The crude lipase was purified to homogeneity by ion-exchange chromatography and gel filtration. The purified lipase had a final recovered activity of 45.42%. Its molecular mass was estimated by SDS-PAGE assay to be 52 kDa. The purified lipase was characterized; the optimum pH was likely between 8 and 9 and showed about 70% of its activity at pH 6.6. The enzyme was very stable at pH 8 and lost about 30% of its activity after holding for 24 h at 4 degrees C in buffer of pH 6.6. The optimum temperature was observed at 37 degrees C and exhibited high activity at 5 degrees C. The thermal inactivation of S. marcescens lipase was more obvious at 80 degrees C; it retained about 15% of its original activity at 80 degrees C and was completely inactivated after heating at 90 degrees C for 5 min. Under optimum conditions, activity of the enzyme was maximum after 6 min. The Michaelis-Menten constant was 1.35 mM on tributyrin. The enzyme was inhibited by a concentration more than 6.25mM. Purified lipase was not as heat-stable as other lipases from psychrotrophs, but it retained high activity at 5 degrees C. At pH 6.6, the pH of milk, purified lipase showed some activity and stability. Also, the organism demonstrated lipolytic activity at 6 degrees C after 12 h. Therefore, S. marcescens and its lipase were considered to cause flavor impairment during cold storage of milk and dairy products.
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PMID:Purification and partial characterization of psychrotrophic Serratia marcescens lipase. 1261 56


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