Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Penicillin acylase is processed from a 90-kD precursor through the cleavage of a leader peptide and two further endopeptidase cleavages to yield an enzyme that contains a 22-kD (or 23-kD) and a 65-kD subunit. The endopeptidase cleavages require an intact carboxy terminus. This type of processing appears to be unique for a prokaryotic enzyme, having its most closely related analog in the synthesis and processing of preproinsulin and other eukaryotic hormones.
J Mol Appl Genet 1985
PMID:Structure of the penicillin acylase gene from Escherichia coli: a periplasmic enzyme that undergoes multiple proteolytic processing. 298 4

A spontaneous mutation in the gene lyt encoding the pneumococcal autolysin has been characterized. This mutation, named lyt-32, which behaves as a high-efficiency marker in pneumococcal transformation, is a single base pair GC deletion causing the appearance of two consecutive termination codons in the amino terminal part of the sequence of the autolysin gene. The mutant lyt gene did not code for a polypeptide of relative molecular mass corresponding to the pneumococcal E form amidase in Escherichia coli maxicells. Pneumococcal cells containing the lyt-32 mutation (M32) were fully transformable, multiplied at a normal growth rate forming small chains and showed a tolerant response when treated with beta-lactam antibiotics. Strain M32 represents the first example of a mutant of Streptococcus pneumoniae completely lacking amidase as a consequence of an alteration in the structural gene coding for the pneumococcal autolysin.
Mol Gen Genet 1986 Aug
PMID:Isolation, characterization and physiological properties of an autolytic-deficient mutant of Streptococcus pneumoniae. 302 Mar 63

Of five amidohydrolase activities subject to nitrogen metabolite repression in Aspergillus nidulans, L-asparaginase shows clearest evidence of also being subject to repression by atmospheric oxygen. Such oxygen repressibility is only evident under nitrogen metabolite derepressed conditions. Asparaginase levels are also considerably elevated by areA300, an altered function allele of the positive acting wide domain regulatory gene areA mediating nitrogen metabolite repression and are drastically reduced by loss of function mutations in areA. A. nidulans has two L-asparaginase enzymes and it has been shown by the use of appropriate mutants that these regulatory effects are exerted on the expression of that specified by the ahrA gene but probably not that specified by the apnA gene.
Mol Gen Genet 1988 May
PMID:An asparaginase of Aspergillus nidulans is subject to oxygen repression in addition to nitrogen metabolite repression. 304 73

We have worked out conditions for the study of competence development and genetic transformation in Streptococcus oralis NCTC 11427 (type strain), a species that contains choline in the cell wall. The peak of competence was found at the early exponential phase of growth and the optimal conditions for transformation were achieved with shuttle plasmids prepared from S. pneumoniae or from Escherichia coli serving as donor DNA. Transformation with dye-buoyant density gradient purified plasmid preparations followed first-order kinetics. The pneumococcal amidase can be expressed in S. oralis harbouring a plasmid carrying the lytA gene. This enzyme lysed the cell wall of the transformed cell in the presence of detergents.
Mol Gen Genet 1988 Dec
PMID:Characterization of genetic transformation in Streptococcus oralis NCTC 11427: expression of the pneumococcal amidase in S. oralis using a new shuttle vector. 324 22

The removal of N-linked oligosaccharides by peptide-N4-[N-acetyl-beta-glucoseaminyl]asparagine amidase (previously known as aspartoglycosylamine amidohydrolase and abbreviated N-glycanase) from the surface of blood or insect-transmissible forms of Trypanosoma cruzi markedly increased the capacity of these organisms to associate with (i.e., bind and penetrate) either mouse peritoneal macrophages or rat heart myoblasts. This effect was evidenced by a significant elevation in both the percentage of infected host cells and the average number of parasites per 100 cells. Conversely, N-glycanase treatment of either host cell markedly reduced both parameters to levels significantly below those obtained with cells mock treated with medium alone. The N-glycanase effect on the parasites was inhibited by heat inactivation of the enzyme or by the presence of fetuin, an N-glycanase substrate. The enhanced capacity of N-glycanase-treated T. cruzi to engage the host cells started to subside 2 h after the treatment, indicating the reversibility of the effect. The decreased reactivity of N-glycanase-treated macrophages or myoblasts with T. cruzi suggests that N-linked oligosaccharides on these host cells are involved in the initial phase of the cell infection process. Instead, because T. cruzi interacted more effectively with host cells after treatment with N-glycanase, parasite surface N-linked oligosaccharides would seem to interfere with the association.
Mol Biochem Parasitol 1987 Jan 15
PMID:Role of membrane N-linked oligosaccharides in host cell interaction with invasive forms of Trypanosoma cruzi. 355 30

The amidase genes of Pseudomonas aeruginosa were inserted into a lambda replacement vector following cleavage with the restriction endonuclease HindIII. The recombinant lambdaami was detected by enhanced growth of Escherichia coli around plaques of the recombinant phage on minimal medium containing acetamide as the nitrogen source. Low levels of amidase activity were detected in E. coli cultures infected with lambdaami and these were sufficient to allow growth with acetamide as nitrogen source. Lysis-defective derivatives of lambdaami were made by introducing Q-, S-, mutations. Cultures of E. coli infected with lambdaamiQ-S- synthesised amidase as the major protein. The amidase produced by these cultures was identical to that produced by PAC strains of P. aeruginosa in substrate specificty, thermal stability and immunological cross-reaction.
Mol Gen Genet 1980 Jan
PMID:The construction in vitro of derivatives of bacteriophage lambda carrying the amidase genes of Pseudomonas aeruginosa. 624 42

Human pro-coagulant alpha-thrombin may be proteolyzed under controlled conditions to the non-coagulant beta- and gamma-thrombin forms. These derivative forms nonetheless retain esterase and amidase activities with small substrates as well as several other thrombin functions. Structurally, human gamma-thrombin consists of three non-covalently associated fragments which retain structural integrity as measured by several spectroscopic criteria as well as enzymatic function. The protein folding characteristics of three-chain gamma-thrombin indicate that each fragment (domain) contains sufficient information to result in a correct renaturation of protein conformation. Those subtle structural differences which distinguish gamma- from alpha-thrombin are most likely the obstructions to fibrinogen binding which account for the loss of clotting activity.
Mol Cell Biochem 1984
PMID:Structure-function relationships in human alpha- and gamma-thrombins. 632 67

Specific radioimmunoassays for thyrotrophin-releasing hormone (TRH) and deamido-TRH (TRH-OH) were used to investigate the inactivation of TRH by subcellular fractions from rat hypothalamus. TRH-OH was rapidly formed from TRH by an amidase present only in the supernatant fraction at an optimum pH of 7.38; although TRH was degraded by the particulate fraction, no TRH-OH formation was detected. Of several brain areas investigated, the cortex had the highest rate of TRH-OH production and the pituitary the lowest. Once formed in the supernatant fractions, it was found that TRH-OH was stable and did not undergo further degradation. Formation of TRH-OH from TRH appears to be an important step in the tripeptide's enzymic degradation in the brain, so the combined use of specific radioimmunoassays for TRH and TRH-OH may provide a suitable means for studies of the enzymes involved, since these enzymes may contribute to the mechanisms regulating the secretion and duration of action of TRH.
Mol Cell Endocrinol 1980 Apr
PMID:Enzymic formation of TRH-OH from TRH by rat hypothalamus. 677 Nov 74

Adenosine kinase, adenosine deaminase, hypoxanthine phosphoribosyltransferase, inosine-nucleoside phosphorylase, 5'-AMP deaminase and 5'-IMP nucleotidase were identified in cell-free extracts of duckling erythrocytes; no evidence for 5'-AMP nucleotidase and xanthine oxidase activity was found. The Km values for the duckling red cell enzymes were similar to those reported for human erythrocytes. Plasmodium lophurae extracts demonstrated similar enzyme activities except for 5'-AMP deaminase and 5'-IMP nucleotidase which were absent. It is proposed that during infection erythrocytic AMP is catabolized to IMP, inosine and hypoxanthine; the hypoxanthine is taken up by the plasmodium, utilized to form IMP, and this in turn is converted into adenine and guanine nucleotides.
Mol Biochem Parasitol 1981 Apr
PMID:Purine metabolizing enzymes of Plasmodium lophurae and its host cell, the duckling (Anas domesticus) erythrocyte. 678 22

The objectives of this study were to determine ascorbic acid stability and its effect on antiproteinase activity of seminal plasma in the presence of an oxidant. Effect of seminal plasma, and additives: glutathione, albumin, hydrogen peroxide and Tris buffer, on ascorbic acid degradation was investigated by UV absorbance. Antiproteinase against trypsin amidase activity was measured spectrophotometrically using N-benzoyl-DL-arginine-p-nitroanilide (BAPNA) as substrate. Ascorbic acid was destroyed much more rapidly with the addition of hydrogen peroxide than in Tris buffer at pH 8.2 alone. Seminal plasma protected ascorbic acid more efficiently than glutathione and albumin alone. The protective effect of seminal plasma on ascorbic acid degradation may closely relate to the function of ascorbic acid in reproductive system of scurvy-prone animals including teleost fish. Within the range of 1-8 mM concentrations, ascorbic acid had a pro-oxidant action on seminal plasma antiproteinase activity in vitro when they were incubated with hydrogen peroxide.
Mol Cell Biochem 1995 Jul 05
PMID:Protective effect of seminal plasma proteins on the degradation of ascorbic acid. 747 34


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