Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: Y22D7AL .14
 53,079 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The tyrosine-3-monooxygenase activity [L-tyrosine, tetrahydropteridine: oxygen oxidoreductase (3-hydroxylating); EC 1.14.16.2] of rat adrenal medulla is induced 20-24 hr after the injection of reserpine (16 mumol/kg intraperitoneally). This and other inducing stimuli increase the 3': 5'-cyclic AMP (cAMP) content in the medulla for longer than 60 min and activate the cAMP-dependent protein kinase (ATP: protein phosphotransferase; EC 2.7.1.37) for several hours. Corticotropin (ACTH), dopamine, and propranolol do not induce the monooxygenase, but elicit an increase in the cAMP content of the medulla which fails to activate protein kinase and lasts less than 1 hr. A high- and low-molecular-weight protein kinase are separated by gel filtration from the 20,000 X g pellet extract of adrenal medulla homogenate. The activity of the low-molecular-weight enzyme is expressed as its ability to phosphorylate histone. The protein kinase activity of the pellet is increased between 3 and 17 hr after reserpine injection. Our evidence indicates that this increase is due to a translocation from cytosol to subcellular structures of a kinase that utilizes lysine-rich histone as phosphate acceptor. The protein kinase activity that is extracted from a purified nuclear fraction prepared from the adrenal medulla of rats injected 7 hr previously with reserpine is greater than that extracted from medulla of saline-treated rats.
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PMID:Activation and nuclear translocation of protein kinase during transsynaptic induction of tyrosine 3-monooxygenase. 0 93

The conversion of L-lysine to its corresponding epsilon-N-hydroxy derivative has been achieved for the first time by cell-free extracts of Aerobacter aerogenes 62-1. Partial fractionation by differential centrifugation (at 12 000 X g) revealed that both supernatant and pellet are essential for maximum enzymatic activity. The omega-N-hydroxylase (EC 1.14.99) was found to function optimally at pH 7-7.5 and exhibited an apparent Km of about 75 muM for L-lysine. L(+)-Lactate or DL-lactate and pyruvate greatly stimulate the omega-N-hydroxylase activity. The system is strongly inhibited by arsenite and sulfite.
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PMID:Effect of metabolites on epsilon-N-hydroxylysine formation in cell-free extracts of Aerobacter aerogenes 62-1. 1 66

A purification of up to 4000-fold is reported for lysyl hydroxylase (EC 1.14.11.4) from extract of chick-embryo homogenate and one of about 300-fold from extract of chick-embryo cartilage. Multiple forms of the enzyme were observed during purification from whole chick embryos. In gel filtration the elution positions of the two main forms corresponded to average molecular weights of about 580000 and 220000. These two forms could also be clearly separated in hydroxyapatite chromatography. In addition, some enzyme activity was always eluted between the two main peaks both in gel filtration and in hydroxyapatite chromatography. The presence of the two main forms was also observed when purifying enzyme from chick embryo cartilage. Both forms of the enzyme hydroxylated lysine in arginine-rich histone, which does not contain any -X-Lys-Gly- sequence. No difference was found between the enzyme from whole chick embryos and from chick embryo cartilage in this respect. Lysyl hydroxylase was found to have affinity for concanavalin A, indicating the presence of some carbohydrate residues in the enzyme molecule. Lysyl and prolyl hydroxylase activities increased when the chick embryo homogenate was assayed in the presence of lysolecithin. Preincubation of the homogenate either with lysolecithin or with Triton X-100 increased lysyl hydroxylase activity in homogenate, and in the 1500 x g and 150000 x g supernatants, suggesting that the increase in the enzyme activity was due to liberation of the enzyme from the membranes. Divalent cations were found to inhibit the activity of lysyl and prolyl hydroxylases in vitro. An inhibition of about 50% was achieved with 15 mM calcium 60 muM copper and 3 muM zinc concentrations. The mode of inhibition was tested with Cu2+, and was found to be competitive with Fe2+.
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PMID:Lysyl hydroxylase. Further purification and characterization of the enzyme from chick embryos and chick embryo cartilage. 18 Oct 88

Antibodies to chromatin proteins of Novikoff hepatoma cells formed precipitin bands in the double-diffusion immunoprecipitation assay with chromatin proteins of Novikoff hepatoma, Walker 256 carcinosarcoma, and 18-day fetal rat liver. The antigen used for preparation of antiserum was the chromatin proteins initially extracted with 3 M NaCl-7 M urea and soluble after dialysis to 0.14 M NaCl-0.35 M urea. The chromatin proteins used for analytical studies were extracted with 0.6 M NaCl containing 0.01 M Tris-HCl (pH 8) and 100 muM phenylmethylsulfonyl fluoride. Corresponding chromatin proteins of normal and 18-hr regenerating rat liver, heart, and kidney did not form precipitin bands. The antigen was purified from the chrmatin of Novikoff hepatoma cells by exclusion chromatography on Sephadex G-150 and preparative nondenaturing polyacrylamide gel electrophoresis. Its migration on denaturing sodium dodecyl sulfate-polyacrylamide gels corresponded to a molecular weight of 26,000. Amino acid analysis showed that the ratio of acidic to basic amino acids was 1.4 to 1.0. Evidence for its homogeneity included its migration as a single protein spot on two-dimensional polyacrylamide gel electrophoresis and its single lysine amino-terminal amino acid. This protein is a glycoprotein, as shown by the presence of 15 moles of galactosamine per mole of antigen. These studies demonstrate the presence of a fetal glycoprotein in the chromatin of two tumors that may have an important role in determining their gene products.
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PMID:A fetal protein in chromatin of Novikoff hepatoma and Walker 256 carcinosarcoma tumors that is absent from normal and regenerating rat liver. 18 70

The effect of diabetes and insulin on the activities of both prolyl hydroxylase (trivial name; proline,2-oxoglutarate dioxygenase, EC 1.14.11.2) and lysyl hydroxylase (trivial name; lysine,2-oxoglutarate dioxygenase, EC 1.14.11.4) in isolated rat renal glomeruli was determined. Three groups of experimental animals were used: age-matched controls, streptozotocin-diabetic, and insulin-treated streptozotocin-diabetic. Using 14C-labeled lysine or proline hydroxylase substrate prepared from chick embryo tibiae, glomerular 17 000 X g supernatant enzyme was incubated in a complete hydroxylating system for 60 and 120 min Lysyl hydroxylase activity was significantly increased in diabetic preparations, but prolyl hydroxylase activity did not differ from control. Administration of insulin to streptozotocin-injected animals completely restored glomerular lysyl hydroxylase to normal levels. The results suggest that the specific elevation of lysyl hydroxylase relates to the biochemical changes contributory to diabetic nephropathy, and that insulin may reverse this process.
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PMID:Effect of diabetes and insulin on rat renal glomerular protocollagen hydroxylase activities. 18 35

In five healthy subjects inhibition of prostaglandin (PG)-synthesis with indomethacin did not significantly alter glomerular filtration, urinary flow rate or sodium and potassium excretion during control urine collection periods or i.v. hypertonic saline infusion. Saline administration was accompanied by a fall in urinary PGEI-excretion from 0.58 +/- 0.14 to 0.26 +/- 0.09 ng/min (p less than 0.05). While indomethacin had no effect on basal urinary osmolality (Uosm), renal concentrating ability following hypertonic saline or i.v. administration of 100 mU lysine-vasopressin significantly increased in the presence of indomethacin with Uosm rising from 805 +/- 25 to 970 +/- 53 mosm/L (p less than 0.01) and from 839 +/- 47 to 996 +/- 62 mosm/L (p less than 0.01), resp. Since this was not accompanied by respective changes in urinary excretion of cyclic adenosine monophosphate (cAMP) mechanisms other than PG-antagonism of vasopressin, such as decreased medullary washout of solute, may contribute to enhanced renal concentrating ability following inhibition of PG-synthesis with indomethacin.
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PMID:Effects of inhibition of prostaglandin-synthesis on renal electrolyte excretion and concentrating ability in healthy man. 21 3

Catechol analogs inhibit the activity of lysyl hydroxylase (peptidyllysine, 2-oxyglutarate: oxygen 5-oxidoreductase, EC 1.14.11.4), a microsomal enzyme which catalyzes the transformation of certain lysyl residues in collagen to hydroxylysine. Chick embryo lysyl hydroxylase activity was measured by specific tritium release as tritiated water from an L-[4,5-3H]lysine-labelled unhydroxylated collagen substrate prepared from chick calvaria. Catechol analogs did not bind irreversibly to either enzyme or substrate, as full activity was restored with dialysis. Addition of excess cofactor, Fe2+, ascorbic acid, or alpha-ketoglutarate, did not affect inhibition. Kinetic analysis revealed that with respect to collagen substrate, catechol demonstrated a noncompetitive type of inhibition with a Ki of 15 muM.
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PMID:Inhibition of lysyl hydroxylase by catechol analogs. 40 45

The primary D-serine deaminase (D-serine dehydratase, EC 4.2.1.14) of Escherichia coli K-12 is unstable within the cell. The protein, a single polypeptide chain, is cleaved at a lysine residue by a cellular proteolytic activity. Fragments containing the active site then aggregate into tetramers, which retain substrate affinity and show very low catalytic activity. Such degradations may represent an evolutionary mechanism for the generation of new enzymes.
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PMID:Specific in vivo cleavage of D-serine deaminase and properties of tetrameric polypeptide aggregates of the fragments. 77 Apr 18

The hydrolysis of proteins contained in the dietetic protein-rich bread with crystalline pepsin, trypsin and chemotrypsin was studied for the first time by using an apparatus devised by A. A. Pokrovsky and I. D. Ertanov and by following procedures as proposed by them (1968). By the end of every hour of the experiment 4.31 and 4.04, 7.88 and 4.90, 9.20 and 6.00, 12.96 and 11.72,19.00 and 12.55, 21.14 and 14.00 per cent of the initial quantity of the proteins contained in these two types of bread were hydrolysed respectively. The susceptibility to the action of enzymes on the part of the study products proved much lower than the theoretical proteinic values of the wheat, rye bread (M. S. Marshak, 1971) and below the results obtained by the analogous tests with the proteolysis of the ordinary bread proteins. Inasmuch as the protein-rich bread is baked according to the 1936 formulation an inference is drawn on the expediency of enriching such bread with dairy protein, rye gluten and belip, which will rresult in a more acceptable ratio of tryptophan/lysine and should, apparently, contribute to a greater intensity of the proteins hydrolysis in case of such a bread when it reaches the stomach and the proximal segment of the small intestine.
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PMID:[In vitro susceptibility of the proteins of wheat-protein and bran-protein bread to attack by gastric and pancreatic proteolytic enzymes]. 78 31

A basic diet containing rice, wheat, and corn that furnished 6.0 g of nitrogen per day was consumed by health young adults. Two levels of lysine, 900 and 1800 mg, and three of tryptophan, 260, 390, and 520 mg, were tested. Lysine exerted a significant effect (P less than 0.05) on nitrogen retention but tryptophan did not. When consumed in conjunction with at least twice the reported minimal requirements of other essential amino acids, 900 mg of lysine induced mean daily balances of 0.15 +/- 0.18, 0.19 +/- 0.14, and 0.22 +/- 0.21 g, respectively, in response to the three levels of tryptophan; and 1800 mg of lysine caused retentions of 0.75 +/- 0.14, 0.77 +/- 0.21 and 0.71 +/- 0.15 g. These findings are discussed in relation to fulfillment of protein and amino acid requirements of adult human subjects.
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PMID:Lysine and tryptophan in cereal-based diets for adult human subjects. 85 10


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