Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0519030 (Klebsiella)
 21,988 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The mechanism for the infection-promoting effect of the capsular polysaccharide of Klebsiella pneumoniae (CPS-K) was investigated using the experimental system in which mice were infected intraperitoneally (i.p.) with a virulent strain of Salmonella enteritidis immediately after i.p. injection of CPS-K. In the peritoneal phagocytes of CPS-K-untreated control mice, approximately 70, 3, and 10% of phagocytized bacteria survived 6, 12, and 24 hr after challenge, respectively, when calculated from the ratio of the number of cell-associated viable bacteria, which was estimated by direct plate count, to the number of phagocytized bacteria, which was estimated by microscopic observation of stained smears. In contrast, almost all of the phagocytized bacteria were viable throughout the experimental period in mice treated with CPS-K. The electron microscopical findings of the phagocytes obtained 12 hr after challenge showed that in the cells of mice treated with CPS-K almost all of the phagocytized bacteria were morphologically intact, with some of them in the stages of cell division, whereas in those of untreated control mice, almost all of the phagocytized bacteria underwent digestive changes. When the reaction product of acid phosphatase was examined by electron microscopy in the phagocytes obtained 12 hr after challenge, the enzyme activity in the phagosomes was very low in mice treated with CPS-K in comparison with that in untreated control mice. Enzyme assays of the lysosomal and extralysosomal fractions of peritoneal cells obtained at various times after challenge also showed that release of acid phosphatase from the lysosomal fraction to the extralysosomal fraction after bacterial challenge was inhibited in peritoneal cells of mice treated with CPS-K.
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PMID:Effect of capsular polysaccharide of Klebsiella pneumoniae on host resistance to bacterial infections. III. Further study of its effects on interactions between peritoneal leukocytes and virulent Salmonella enteritidis. 38 55

1. Phosphatase synthesis was studied in Klebsiella aerogenes grown in a wide range of continuous-culture systems. 2. Maximum acid phosphatase synthesis was associated with nutrient-limited, particularly carbohydrate-limited, growth at a relatively low rate, glucose-limited cells exhibiting the highest activity. Compared with glucose as the carbon-limiting growth material, other sugars not only altered the activity but also changed the pH-activity profile of the enzyme(s). 3. The affinity of the acid phosphatase in glucose-limited cells towards p-nitrophenyl phosphate (K(m) 0.25-0.43mm) was similar to that of staphylococcal acid phosphatase but was ten times greater than that of the Escherichia coli enzyme. 4. PO(4) (3-)-limitation derepressed alkaline phosphatase synthesis but the amounts of activity were largely independent of the carbon source used for growth. 5. The enzymes were further differentiated by the effect of adding inhibitors (F(-), PO(4) (3-)) and sugars to the reaction mixture during the assays. In particular, it was shown that adding glucose, but not other sugars, stimulated the rate of hydrolysis of p-nitrophenyl phosphate by the acid phosphatase in carbohydrate-limited cells at low pH values (<4.6) but inhibited it at high pH values (>4.6). Alkaline phosphatase activity was unaffected. 6. The function of phosphatases in general is discussed and possible mechanisms for the glucose effect are outlined.
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PMID:Phosphatase synthesis in Klebsiella (aerobacter) aerogenes growing in continuous culture. 434 13

Physicochemical properties and systemic effects of the enterotoxin of Klebsiella pneumoniae has been studied. The enterotoxin had a molecular weight between 10 000 to 50 000. It was protein in nature, and heat and acid stable, inducing a dilatatory response in the gut. It haemolyzed the erythrocytes of various animals including man. It had a capillary permeability activity. In addition, when administered parenterally it increased the level of blood glucose, serum cholesterol, serum alkaline phosphatase and serum acid phosphatase.
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PMID:Klebsiella pneumoniae enterotoxin. II. Physicochemical properties of enterotoxin. 676 11

A single intraperitoneal injection of the phenol-treated cells of Propionibacterium acnes into mice showed nonspecific resistance against subsequent lethal doses of an intraperitoneal challenge of Klebsiella pneumoniae, Staphylococcus aureus, and Streptococcus pyogenes. The protection showed a biphasic pattern. The maximum protection, designated as the early phase protection, was seen in mice injected with P. acnes vaccine 1 to 2 days before the challenge, whereas the late phase protection was seen in mice vaccinated 16 to 22 days before the challenge. The activity of the reticuloendothelial system in mice after vaccination also showed a biphasic pattern with the peak on days 4 and 12. The delayed activation of the reticuloendothelial system lasted up to 3 weeks and coincided with the period of the late phase protection. The early phase resistance was markedly impaired by the treatment with hydrocortisone and carrageenan, but not by the treatment with anti-thymocyte serum, actinomycin D, or cyclophosphamide. The number of peritoneal polymorphonuclear leukocytes in vaccinated mice increased on days 1 to 2. The number of macrophages also increased at 2 to 21 days after vaccination and reached its maximum on day 14. Total activities of acid phosphatase, Nitro Blue Tetrazolium reduction, and the phagocytic activities of peritoneal exudate cells were also enhanced on and after day 1 after the injection of P. acnes vaccine.
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PMID:Biphasic protection against bacterial infection in mice induced by vaccination of Propionibacterium acnes. 738 May 36

A Citrobacter sp. was reported previously to accumulate heavy metals as cell-bound heavy metal phosphates. Metal uptake is mediated by the activity of a periplasmic acid-type phosphatase that liberates inorganic phosphate to provide the precipitant ligand for heavy metals presented to the cells. Amino acid sequencing of peptide fragments of the purified enzyme revealed significant homology to the phoN product (acid phosphatase) of some other enterobacteria. These organisms, together with Klebsiella pneumoniae, previously reported to produce acid phosphatase, were tested for their ability to remove uranium and lanthanum from challenge solutions supplemented with phosphatase substrate. The coupling of phosphate liberation to metal bioaccumulation was limited to the metal accumulating Citrobacter sp.; therefore the participation of species-specific additional factors in metal bioaccumulation was suggested.
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PMID:Phosphatase-mediated heavy metal accumulation by a Citrobacter sp. and related enterobacteria. 792 62

We have investigated the enzymatic phosphorylation of nucleosides and found that Morganella morganii phoC acid phosphatase exhibits regioselective pyrophosphate (PP(i))-nucleoside phosphotransferase activity. In this study, we isolated genes encoding an acid phosphatase with regioselective phosphotransferase activity (AP/PTase) from Providencia stuartii, Enterobacter aerogenes, Escherichia blattae and Klebsiella planticola, and compared the primary structures and enzymatic characteristics of these enzymes with those of AP/PTase (PhoC acid phosphatase) from M. morganii. The enzymes were highly homologous in primary structure with M. morganii AP/PTase, and are classified as class A1 acid phosphatases. The synthesis of inosine-5'-monophosphate (5'-IMP) by E. coli overproducing each acid phosphatase was investigated. The P. stuartii enzyme, which is most closely related to the M. morganii enzyme, exhibited high 5'-IMP productivity, similar to the M. morganii enzyme. The 5'-IMP productivities of the E. aerogenes, E. blattae and K. planticola enzymes were inferior to those of the former two enzymes. This result underlines the importance of lower K(m) values for efficient nucleotide production. As these enzymes exhibited a very high degree of homology at the amino acid sequence level, it is likely that local sequence differences in the binding pocket are responsible for the differences in the nucleoside-PP(i) phosphotransferase reaction.
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PMID:Acid phosphatase/phosphotransferases from enteric bacteria. 1623 57

The extracellular phytase of the plant-associated Klebsiella sp. ASR1 is a member of the histidine-acid-phosphatase family and acts primarily as a scavenger of phosphate groups locked in the phytic acid molecule. The Klebsiella enzyme is distinguished from the Escherichia coli phytase AppA by its sequence and phytate degradation pathway. The crystal structure of the phytase from Klebsiella sp. ASR1 has been determined to 1.7 A resolution using single-wavelength anomalous-diffraction phasing. Despite low sequence similarity, the overall structure of Klebsiella phytase bears similarity to other histidine-acid phosphatases, such as E. coli phytase, glucose-1-phosphatase and human prostatic-acid phosphatase. The polypeptide chain is organized into an alpha and an alpha/beta domain, and the active site is located in a positively charged cleft between the domains. Three sulfate ions bound to the catalytic pocket of an inactive mutant suggest a unique binding mode for its substrate phytate. Even in the absence of substrate, the Klebsiella phytase is closer in structure to the E. coli phytase AppA in its substrate-bound form than to phytate-free AppA. This is taken to suggest a preformed substrate-binding site in Klebsiella phytase. Differences in habitat and substrate availability thus gave rise to enzymes with different substrate-binding modes, specificities and kinetics.
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PMID:Crystal structure of Klebsiella sp. ASR1 phytase suggests substrate binding to a preformed active site that meets the requirements of a plant rhizosphere enzyme. 2039 4