Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In Pseudomonas aeruginosa, phosphate limitation results in the synthesis of several protein species. We report the cloning of the P. aeruginosa alkaline phosphatase structural gene, phoA, and we show that this gene is regulated normally in Escherichia coli. We have also identified and cloned two P. aeruginosa genes which can complement phoB and phoR mutations in E. coli. This suggests that a pho regulon system similar to that in E. coli may exist in P. aeruginosa, using at least two similar regulatory factors.
Mol Gen Genet 1988 Jun
PMID:Phosphate regulation in Pseudomonas aeruginosa: cloning of the alkaline phosphatase gene and identification of phoB- and phoR-like genes. 313 29

A role for one of many exocellular enzymes produced by Pseudomonas aeruginosa--phospholipase C (PLC)--as a prime candidate virulence factor in fleecerot dermatitis has been examined. The addition of Tween 80 in tryptose minimal medium effectively perturbed the membrane system of a field isolate of P. aeruginosa, resulting in increased production and release of a periplasmic enzyme marker, alkaline phosphatase (AP), and also of PLC. PLC activity levels in the culture supernatant were 10- to 15-fold higher in the presence of Tween than in its absence. Apart from AP, the culture medium contained little or no detectable proteolytic enzyme activity, thereby facilitating the partial purification of a haemolytic form of PLC by anion-exchange chromatography. This enzyme, when injected intradermally into the skin of sheep, elicited histopathological lesions virtually identical to those seen in naturally occurring fleecerot. In addition, serum from each of eight sheep afflicted with fleecerot contained high levels of circulating anti-PLC antibody activity when assayed by ELISA. Since these antibodies did not affect the enzymic function of PLC, it is likely that they do not bind to, or are incapable of conformational modification of, the active site.
J Gen Microbiol 1988 Sep
PMID:Biological properties of phospholipase C purified from a fleecerot isolate of Pseudomonas aeruginosa. 315 Dec 9

Fusion of the alkaline phosphatase gene (phoA) which lacks its own signal peptide sequence to the N-terminal region of hlyA, the structural gene for Escherichia coli haemolysin, leads to active alkaline phosphatase (AP). AP activity depends on the length of the N-terminal region of hlyA. An optimum is reached when 100-200 amino acids of HlyA are fused to PhoA but fusion of as little as 13 amino acids of HlyA to PhoA is sufficient to yield appreciable AP activity. When cells are treated with lysozyme most of the AP activity is found associated with the membrane fraction but a substantial amount is also found in the soluble fraction, most of which may represent a periplasmic pool of AP. The soluble portion of AP activity is significantly increased when the cells are disrupted by ultrasonication, which indicates that the fusion proteins are only loosely associated with the membrane and that large parts are already located on the outside of the cytoplasmic membrane. The expected fusion proteins were identified in the soluble and the membrane fractions and their amounts in these fractions correlated well with AP activity.
Mol Gen Genet 1987 Jun
PMID:Alkaline phosphatase which lacks its own signal sequence becomes enzymatically active when fused to N-terminal sequences of Escherichia coli haemolysin (HlyA). 330 15

Mutants of Escherichia coli K12 carrying exc mutations inducing the release of the plasmid pBR322-encoded beta-lactamase (EC 3.5.2.6) into the extracellular medium were analysed and compared with previously described excretory mutants carrying lky mutations associated with the release of alkaline phosphatase and to tolA and tolB mutants, originally described as tolerant towards various colicins. The exc, lky and tol mutations mapped near the gal operon at min 16.5 of the E. coli linkage map. A genetic analysis presented in this paper showed that some exc and lky mutations belonged to the tolA and tolB complementation groups. Furthermore, we identified a third cistron, excC, involved in the excretion of periplasmic enzymes but distinct from the two others.
Mol Gen Genet 1987 Sep
PMID:tolA, tolB and excC, three cistrons involved in the control of pleiotropic release of periplasmic proteins by Escherichia coli K12. 331 62

Alkaline phosphatase isoenzyme determination (APID) is in common use despite evidence suggesting that the results correlate poorly with actual sites of disease. To assess the predictive value of this test in clinical practice, 99 APIDs performed on 94 patients were identified and the patients' charts were reviewed. Results of APID were compared with actual patient diagnoses as determined by other means. The liver isoenzyme fraction was not very accurate in predicting the presence of liver disease (positive predictive value 68%). In contrast, the bone isoenzyme fraction was insensitive (56%) but a positive test predicted bone disease well (positive predictive value 93%). The association of elevated transaminases with elevated alkaline phosphatase on a chemistry profile was as useful as APID in identifying liver disease, suggesting that APID should not be done in this setting. Using this information, APID can be helpful in the assessment of an ill patient with an elevated alkaline phosphatase.
J Gen Intern Med
PMID:The accuracy of alkaline phosphatase isoenzyme determination. 340 93

lky mutants of Escherichia coli K12 spontaneously released alkaline phosphatase (APase) into the extracellular medium to give up to 300 units ml-1. APase is a phosphate repressible periplasmic enzyme encoded by the gene phoA. With a view to establishing a method of easy purification, we have analysed APase synthesis and release patterns of isogenic lky strains containing either a constitutive pho regulatory mutation, or a hybrid plasmid carrying the structural gene phoA+ and pho regulatory genes, or a transducing phi 80 phoA+ phage. In the presence of the phoS2333 mutation, F- lky strains lysogenized with phi 80 phoBin phoA+ phage and grown in high phosphate medium were able to release eight times more APase activity (2300 units ml-1) than haploid strain 2336 (phoS+ lky) grown in low phosphate medium. Neither protein synthesis, the cell export machinery nor leakage mechanisms were limiting for APase release. Sufficient APase was released into the medium to facilitate its purification.
J Gen Microbiol 1986 Jan
PMID:Effects of pho regulatory mutations and phoA gene amplification on alkaline phosphatase synthesis and release by lky mutants of Escherichia coli K12. 351 53

Mice orally infected with Campylobacter jejuni developed focal infiltrative necrotic lesions in the liver, as determined by both histology and liver function tests. The initial histopathological feature was a focal infiltrative lesion in the parenchyma and portal triads. Foci of infiltrative lesions became necrotic between days 30 and 60 post-inoculation (p.i.). During this period, portal infiltrates increased in severity. From month 4 p.i., focal areas of infiltrative necrosis in the liver parenchyma became extensive. Study of liver function demonstrated mild elevations of transaminases, alkaline phosphatase and lactic dehydrogenase, and also the presence of hypoalbuminaemia. Although histopathological changes of the liver became gradually more marked after day 30 p.i., liver functions of infected mice were most affected at 2 months p.i. The capacity of C. jejuni to induce hepatic lesions seemed to be related to that of organisms to persist in the gall bladder; there was no correlation between biliary carriage in infected mice and positive faecal culture.
J Gen Microbiol 1986 Nov
PMID:Hepatic lesions in experimental Campylobacter jejuni infection of mice. 362 68

The most abundantly secreted protein from Bacillus licheniformis MC14 is alkaline phosphatase (APase). A twofold purification yields a homogeneous enzyme. No discernible chemical-physical differences in the secreted APase distinguish this enzyme from the cell-bound APase(s) except a 10-fold higher specific activity. During the growth phase in which the bacterium was secreting APase into the medium an inactive cytosol protein antigenically similar but 3000 Da heavier than the subunit of the mature secreted APase was immunoprecipitated from the cytosol. A pulse-chase experiment showed the kinetics of disappearance of this protein from the cytosol to be correlated with the appearance of the secreted APase in the medium, suggesting that it may be a precursor to the secreted APase.
J Gen Microbiol 1986 Aug
PMID:Purification and characterization of the secreted alkaline phosphatase of Bacillus licheniformis MC14: identification of a possible precursor. 379 50

Like the synthesis of alkaline phosphatase, the synthesis of outer membrane PhoE protein is shown to be dependent on the phoM gene product in phoR mutants of E. coli K12. This phoM gene has been cloned into the multi-copy vector pACYC184 using selection for alkaline phosphatase constitutive synthesis in a phoR background. The gene was localized on the hybrid plasmids by analysis of deletion plasmids constructed in vitro and of mutant plasmids generated by gamma delta insertions. Interestingly, two of the selected hybrid plasmids contained the entire phoA-phoB-phoR region of the chromosome, as a multiple copy state of these genes results in the constitutive synthesis of alkaline phosphatase. The presence of multiple copies of the phoM gene hardly influences the level of expression of alkaline phosphatase and PhoE protein in a pho+ strain, but significantly increases the levels of these proteins in a phoR mutant strain.
Mol Gen Genet 1984
PMID:Cloning of phoM, a gene involved in regulation of the synthesis of phosphate limitation inducible proteins in Escherichia coli K12. 609 47

An alpha-amylase gene from Bacillus coagulans has previously been cloned in Escherichia coli and shown to direct the synthesis of an enzymically active protein of 60,000 Dal (Cornelis et al., 1982). In one particular E. coli host, strain HB101, amylase was found to accumulate in the periplasmic space. To study the processing and the location of the amylase, plasmid pAMY2 was introduced into E. coli 188 which is a strain constitutive for alkaline phosphatase, a periplasmic marker, and for beta-galactosidase, a cytoplasmic marker. Abnormally large amounts of both alpha-amylase and beta-galactosidase were found in the culture fluid of cells grown in rich medium. Furthermore a severe growth defect was found when cells containing pAMY2 were grown in maltose and glycerol media, while the ability to grow on glucose remained normal. This defect could be reversed by two types of spontaneous mutations. Mutations in the first class are located on the plasmid and correspond to the insertional inactivation of the amylase gene by IS1. Mutations in the second class are located on the host chromosome. These results suggest that the synthesis and export of B. coagulans alpha-amylase is deleterious to E. coli, especially in media containing maltose or glycerol as sole carbon source.
J Gen Microbiol 1983 Feb
PMID:Growth defects of Escherichia coli cells which contain the gene of an alpha-amylase from Bacillus coagulans on a multicopy plasmid. 618 99


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