Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.5.1.4 (deaminase)
 5,113 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

When leukocyte lysosomal extracts are used as a source of elastase and are combined with a fraction of plasma containing sufficient alpha 1-protease inhibitor (alpha 1-Pi) to inhibit all but 30 to 40% of the elastase amidase activity, elastolysis occurs at 69% of the rate of the uninhibited elastase controls (0.125 M NaCl; pH, 6.5). Proteolysis of elastin requires the presence of NaCl. At pH 8.6, elastolysis is decreased to 30 to 40% of free elastase controls by 1.0 M NaCl. At pH 6.5, on the other hand, elastolysis is increased to 83% of the control values by these higher NaCl concentrations. The activity of human leukocyte myeloperoxidase is optimal at pH 6 to 6.5 and at NaCl concentrations between 0.25 and 1.0 M. Purified myeloperoxidase, alpha 1-Pi, and elastase, in the presence of NaCl and hydrogen peroxide, can reproduce this phenomenon at pH 6.5, suggesting that the occurrence of elastolysis in lysosomal extract-plasma mixtures may in part be a result of the oxidative inactivation of alpha 1-Pi by myeloperoxidase present in the lysosomal extract. Human ceruloplasmin, the major antioxidant of plasma, inhibits this myeloperoxidase-dependent reaction, without interfering either with free elastase activity or with the appearance of activity in plasma-lysosomal extract mixtures at pH 8.6. The "antioxidant" activity of ceruloplasmin is inhibited by azide. These results suggest that antioxidants such as ceruloplasmin may be an important determinant of lung defense in persons chronically exposed to oxidants.
Am Rev Respir Dis 1982 Sep
PMID:Ceruloplasmin: plasma inhibitor of the oxidative inactivation of alpha 1-protease inhibitor. 628 6

The characteristics of isoniazid amidase which hydrolyzes isoniazid to isonicotinic acid and hydrazine was examined in vitro using rat liver subcellular fractions. The activity of isoniazid amidase was estimated from the amount of hydrazine produced from a substrate, isoniazid, by means of GC-MS. High activity of the amidase was observed in the microsomal and lysosomal fractions, and at pH 7.4-7.8 in the microsomal fraction. The amidase was not inhibited by acetanilide, but by procaine and bis(p-nitrophenyl)phosphate. As expected, acetylisoniazid, a main metabolite of isoniazid, also inhibited the amidase. Not only the microsomal monooxygenase but also amidase was strongly induced by pretreatment with phenobarbital, 3-methylcholanthrene and rifampicin, respectively.
J UOEH 1984 Sep 01
PMID:Metabolic hydrolysis of isoniazid by subcellular fractions of rat liver. 649 51

Previous analysis of soluble peptidoglycan (PG) fragments released by exponentially growing gonococci implicated the combined action of both hexosaminidase and amidase activities in PG turnover. Current studies further characterized PG fragments which were labeled in the glycan with D-glucosamine and in the peptide moiety with meso-diaminopimelic acid of L- and D-alanine. Labeled PG fragments were isolated by gel filtration and characterized on the bases of (i) KD values, (ii) free amino group analysis using fluorodinitrobenzene, (iii) borohydride reduction, (iv) alkali-catalyzed beta-elimination, (v) paper chromatography in various solvents, (vi) electrophoretic mobility at various pH values, (vii) digestibility by Charonia lampas glycosidases, and (viii) content of labeled D- and L-alanine. A set of well-characterized PG fragments was used as standards. The monomer fraction (the major extracellular product) was found to contain two components. Most (about 80%) appeared to be N-acetylglucosaminyl-beta-1 leads to 4-1,6-anhydro-N-acetylmuramyl-L-ala-D-glu-meso-diaminopimelic acid; the remainder was the corresponding disaccharide tetrapeptide containing a C-terminal D-alanine. An unusual feature of these products was the presence of the anhydro-muramyl (non-reducing) ends, reflecting the activity of a gonococcal transglycosylase, and the near absence of products containing detectable reducing ends. Otherwise, the structures of the monomer fragments were typical of those expected for a gram-negative bacterium (chemotype I). The corresponding peptide-cross-linked dimer and the free disaccharide also contained nonreducing ends, exclusively. Free peptides (products of amidase activity) consisted of both tripeptide and tetrapeptide. In summary, all gonococci examined appear to possess an unusual transglycosylase activity which contributes to the release of soluble PG fragments containing nonreducing, anhydro-muramyl ends. The release of these fragments in vivo might be a unique aspect of gonococci-host interactions.
Infect Immun 1980 Sep
PMID:Release of soluble peptidoglycan from growing conococci: demonstration of anhydro-muramyl-containing fragments. 677 63

Adenosine deaminase from Bacillus cereus is quite unstable, similarly to other bacterial deaminases, but it shows a peculiar stabilizing effect by some monovalent cations. These include K+, Li+, NH4+ and to a lesser extent Cs+. Maximal stabilization of the deaminase is exerted by K+ at concentrations higher than 20 mM. The enzyme can be rapidly inactivated by sulphydryl reagents such as p-hydroxymercuribenzoate. Since adenosine deaminase from B. cereus, in addition to monovalent cations, is stabilized also by dithiothreitol, a possible influence of monovalent cations on the reactivity of some sulphydryl groups on the enzyme has been suggested.
Boll Soc Ital Biol Sper 1982 Sep 30
PMID:Preliminary characterization of adenosine deaminase from Bacillus cereus. 681 69

We studied the effect of ions on the ability of purified human urinary kallikrein to cleave its natural substrate (kininogen) as well as two synthetic substrates, tosylarginine [3H]methyl ester and Pro-Phe-Arg-[3H]benzylamide. The kininogenase activity of kallikrein is markedly dependent upon the concentration of cations in vitro. Kininogenase activity is very low when measured in a low electrolyte buffer. The addition of cations to the reaction mixture increases activity by up to 27-fold. Maximum activity is achieved with 100 mM sodium, 100 mM potassium, or 20 mM magnesium. The activity is stable at higher concentrations of cation. Renal kallikrein is believed to act within distal tubular fluid in vivo. The concentration of cations in this fluid varies widely in response to alterations in salt and water metabolism. Thus, the relationship of kininogenase activity to the concentration of cations demonstrated in vitro may be relevant to the activity of kallikrein at its presumed site of action in the kidney. In separate experiments, we evaluated the effect of ions on the amidase and esterase activities of kallikrein which are the basis of several assays in routine use for physiological studies. In contrast to their stimulatory effect on kininogenase activity, cations inhibit amidase and to a lesser extent esterase activity. Additional studies indicate that urinary cations probably account entirely for the well known ability of normal urine to inhibit the amidase and esterase activities of kallikrein.
J Biol Chem 1982 Sep 25
PMID:The effect of cations on the activity of human urinary kallikrein. 692 Dec 2

It has been observed that adenosine deaminase activity in human beings differ between serum and tissues reference to optimal pH, Km and relative substrate specificity. Based upon the ratio between the activity of deaminase on 2'deoxyadenosine and adenosine, we may distinguish between a "serum type" enzyme and a "tissue type" enzyme. In sample of pleural and peritoneal fluid extracted from 92 patients with variable pathology, we have found the existence of a "tissue type" enzyme in three patients having empyemic pleural effusions and ten with malignant systemic pathology.
Boll Soc Ital Biol Sper 1981 Sep 30
PMID:[2'Deoxyadenosine/adenosine deaminase ratio in pleural and peritoneal effusions. Diagnostic significance]. 697 75

Boar acrosin, a glycoprotein present in the acrosome of spermatozoa, tends to aggregate in the absence of detergents and lipids. Self-association products were analyzed electrophoretically by the method of Ferguson. Molecular weights ranging from 44 000 up to 237 000 were found, corresponding to acrosin monomer up to hexamer. Involvement of the active site of the serine proteinase in the formation of oligomers was demonstrated by active enzyme staining and determination of amidase activity of aggregated acrosin. Only monomeric acrosin proved to have full activity, while a marked decrease in specific activity was found upon aggregation. Hence, evidence is presented that acrosin has hydrophobic binding sites modulating the proteinase activity.
Hoppe Seylers Z Physiol Chem 1980 Sep
PMID:Oligomerisation of boar acrosin. 700 57

Two amidases have been partially purified from the slime mold Dictyostelium discoideum; these act sequentially on the beta-hydroxymyristyl-amide groups present in the lipopolysaccharide derivative (4'-O-phosphoryl-N-beta-hydroxymyristyl-D-glucosaminyl)-beta-(1 leads to 6)-N-beta-hydroxymyristyl-D-glucosamine-1-phosphate (III). Amidase-I, which specifically removes the myristyl chain near the 1-phosphate of compound III (apparent Km, 3.7 microM), has been purified 110-fold from a lysate of D. discoideum NC4 cultivated on Escherichia coli. The partially purified enzyme contains no other amidase or phosphatase activities; however, an esterase activity can be detected. The second amidase has been purified about 12-fold from the extracellular fluid of D. discoideum AX3 cultured axenically. This amidase hydrolyzes the distal amide linkage in III (apparent Km, approximately 20 microM) only after prior deacylation of the first site by amidase-I. The preparation is free from phosphatases and glycosidases that can act on lipopolysaccharide. The differential expression of the amidases in D. discoideum and some of their kinetic properties have been described. The amidases should prove useful in structure-function studies of lipopolysaccharide.
J Biol Chem 1982 Sep 10
PMID:Fatty acyl amidases from Dictyostelium discoideum that act on lipopolysaccharide and derivatives. I. Partial purification and properties. 710 2

The substrate specificities of two fatty acyl amidases partially purified from the slime mold Dictyostelium discoideum have been studied. The amidase act on lipopolysaccharide derivatives, such as (4'-O-phosphoryl-N-beta-hydroxymyristyl-D-glucosaminyl)-beta-(1 leads to 6)-N-beta-hydroxymyristyl-D-glucosamine-1-phosphate (III) in a sequential manner. Amidase-I removes the beta-hydroxymyristyl residue present on the amino group adjacent to the 1-phosphate and the product formed is a substrate for amidase-II; the latter removes the remaining beta-hydroxymyristyl residue from the distal amino group. Compound III itself is resistant to amidase-II. Removal of the C-1 or C-4 phosphate groups does not influence recognition by the amidases or their sequential action. Both amidases are specific for long chain fatty amide linkages. Thus, a formyl group on the glucosamine amino group adjacent to the C-1 phosphate is not hydrolyzed by amidase-I; however, this substituent does not hinder the action of amidase-II on the distal fatty acyl amide. The presence of the beta-hydroxyl group in myristyl-amide residues is not required for hydrolysis. Further, while amidase-I requires disaccharide structures for its action, amidase-II acts on monosaccharides as well. Finally, the effects of a variety of substrate analogs and divalent ions on the activity of the enzymes are reported.
J Biol Chem 1982 Sep 10
PMID:Fatty acyl amidases from Dictyostelium discoideum that act on lipopolysaccharide and derivatives. II. Aspects of substrate specificity. 710 3

Cell-free extracts of Brevibacterium sp. L5 grown on DL-erythro-3,5-diaminohexanoate were found to contain a 3-keto-5-aminohexanoate cleavage enzyme that converts 3-keto-5-aminohexanoate and acetyl-coenzyme A (CokA) to 3-aminobutyryl-CoA and acetoacetate and a deaminase that coverts L-3-aminobutyryl-CoA to crotonyl-CoA. The cleavage enzyme has been purified extensively, and some of its properties have been determined for comparison with the 3-keto-6-acetamido-hexanoate cleavage enzyme of Pseudomonas sp. B4. The deaminase has been partially purified and characterized. Both the cleavage enzyme and the deaminase are induced by growth on 3,5-diaminohexanoate. The presence of these and other accessory enzymes in Brevibacterium sp. extracts accounts for the results of earlier tracer experiments which showed that C-1 and C-2 of 3-keto-5-aminohexanoate are converted mainly to acetoacetate and acetate, whereas C-3 to C-6 are converted mainly to 3-hydroxybutyrate or its coenzyme A thiolester. The enzymes observed in extracts of Brevibacterium sp. can account for the conversion of 3,5-diaminohexanoate to acetyl-CoA.
J Bacteriol 1980 Sep
PMID:Enzymes involved in 3,5-diaminohexanoate degradation by Brevibacterium sp. 741 Mar 15


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