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)

Liver glycogen synthase b phosphatase, chromatographically separable from phosphorylase a phosphatase, is decreased in 48-hour alloxan diabetic rats. The phosphatase activities are measured in an in vitro system using exogenous isolated phospho-enzyme as substrates with added phosphatases. Synthase and phosphorylase phosphatases were shown to have differential catalytic properties by their reactivity in the presence of Pi, the heat-stable inhibitor of phosphorylase phosphatase and after incubation with added cAMP-dependent protein kinase.
Mol Cell Biochem 1979 May 06
PMID:Insulin sensitivity of liver glycogen synthase b into a conversion. 11 80

1. The activities of some membrane-bound enzymes such as adenylate cyclase, Na+ + K+-stimulated adenosine triphosphatase (Na+ + K+-ATPase), Ca2+-stimulated ATPase and Mg2+-stimulated ATPase were examined in heart sarcolemmal fractions from control and cardiomyopathic hamsters at different stages of heart failure. 2. The basal adenylate cyclase activity in sarcolemma from cardiomyopathic animals with early, moderate and late stages of heart failure was not different from the control values whereas the sodium fluoride- and catecholamine-stimulated adenylate cyclase activities were depressed in cardiomyopathic sarcolemma at moderate and late stages. 3. The sarcolemmal Na+ + K+-ATPase activity was decreased and the non-specific phosphatase activity was increased at early, moderate and late stages of heart failure. 4. The sarcolemmal Ca2+-ATPase activity was decreased at moderate and late stages whereas the Mg2+-ATPase activity was decreased at the late stages of heart failure only. 5. A marked decrease was found in calcium binding by heart sarcolemma from cardiomyopathic hamsters at late stages of failure. 6. These results suggest that dramatic sarcolemmal changes are associated with heart failure, and support the view that membrane abnormalities play a crucial role in the development of myocardial dysfunction, cyclase, calcium binding, heart failure, heart membranes, sarcolemmal enzymes.
Clin Sci Mol Med 1976 Sep
PMID:Comparison of heart sarcolemmal enzyme activities in normal and cardiomyopathic (UM-X7.1) hamsters. 13 61

Previous studies by others have indicated that the synthesis of secreted enzymes is unusually sensitive to many translation inhibitors and resistant, for about 30 min, to rifampicin. We have studied the sensitivity of secreted (periplasmic) phosphatases to such inhibitors. Alkaline phosphatase synthesis is more sensitive than total protein synthesis to tetracyclin and spectinomycin, but not to sparsomycin, streptomycin, chloramphenicol, kasugamycin, blasticidin S or thiostrepton; it is slightly more resistant than total protein synthesis to the latter two antibiotics. Acid hexose-phosphatase was also preferentially sensitive to tetracyclin and spectinomycin and also to kasugamycin. beta-galactosidase was also included in the study, as an intracellular enzyme, and was found to be preferentially inhibited ("repressed"), sometimes transiently, by all eight translation inhibitors. This effect did not seem to be mediated through cyclic AMP or guanosine tetraphosphate; the "repression" was still evident in mutants with altered rho factor indicating that it may also not be related to artificial polarity. Synthesis of both periplasmic phosphatases was immediately inhibited by rifampicin. These results differ from those found in previous studies with other organisms and suggest a reappraisal of the usual interpretation of these phenomena.
Mol Gen Genet 1977 Jul 07
PMID:The effect of translation and transcription inhibitors on the synthesis of periplasmic phosphatases in E. coli. 14 3

The Hill-parameters : max. velocity (VM), affinity constant (K) and resultant reaction order (n) of an alk. phosphatase (Mol. Weight 100 to 130,000) from guts of foraging worker-bees, have been calculated according to new algebraic equations allowing a rigorous determination without any extrapolation. The parameters determined from 2 strains of the same race, at 3 years interval, do not differ, and the Hill coefficients (n) are significantly lower than 1, namely : n = 0.621 +/- 0.014 (3 detn.) and n = 0,600 +/- 0,016 (t detn.) which suggest the hypothesis of a negative cooperative mechanism.
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PMID:[Kinetic properties of an alkaline phosphatase from honeybee intestine determined by a new rigorous algebraic method]. 15 98

In mammalian tissues, two types of regulation of the pyruvate dehydrogenase complex have been described: end product inhibition by acetyl CoA and NADH: and the interconversion of an inactive phosphorylated form and an active nonphosphorylated form by an ATP requiring kinase and a specific phosphatase. This article is largely concerned with the latter type of regulation of the complex in adipose tissue by insulin (and other hormones) and in heart muscle by lipid fuels. Effectors of the two interconverting enzymes include pyruvate and ADP which inhibit the kinase, acetoin which activates the kinase and Ca2+ and Mg2+ which both activate the phosphatase and inhibit the kinase. Evidence is presented that all components of the pyruvate dehydrogenase complex including the phosphatase and kinase are located within the inner mitochondrial membrane. Direct measurements of the matrix concentration of substrates and effectors is not possible by techniques presently available. This is the key problem in the identification of the mechansims involved in the alterations in pyruvate dehydrogenase activity observed in adipose tissue and muscle. A number of indirect approaches have been used and these are reviewed. Most hopeful is the recent finding in this laboratory that in both adipose tissue and heart muscle, differences in activity of pyruvate dehydrogenase in the intact tissue persist during preparation and subsequent incubation of mitochondria.
Mol Cell Biochem 1975 Oct 31
PMID:Regulation of mammalian pyruvate dehydrogenase. 17 57

1. The pyruvate dehydrogenase complex from human heart has been partially purified and shown to be regulated by a phosphorylation-dephosphorylation cycle similar to that previously found for other mammalian tissues. 2. Incubation of the complex with ATP (2 mmol/1) led to its inactivation associated with the concomitant incorporation into the protein of 32P from the terminal phosphate group of the ATP. Pyruvate, ADP, thiamin pyrophosphate and dichloroacetate diminished the rate of inactivation by ATP. 3. Pyruvate dehydrogenase phosphatase from human heart requires Mg2+ for activity and is sensitive to Ca2+ at concentrations of a few mumol/1. Similar ionic requirements of the skeletal muscle phosphatase have been demonstrated in a crude tissue extract. 4. The activity of pyruvate dehydrogenase in human adipose tissue was less than 10% of typical values in rats. This could be due to the high level of dietary fat consumed by humans, which is known to repress the enzyme activity in rats.
Clin Sci Mol Med 1976 Nov
PMID:Regulation of the human pyruvate dehydrogenase complex. 18 26

In Chlamydomonas reinhardi, mutations in either of two unlinked genes (PD2 and PD3) abolish the activity of the derepressible neutral phosphatase. The question arose whether these genes (or one of them) specify the structure of the enzyme or whether they have a regulatory function. Three mutants producing an active phosphatase at 25 degrees C but not at 35 degrees C were isolated and investigated. One of these mutants (PDts11) was allelic with PD2, another one (PDts12) was linked to PD3 and the third one (PDts13) was linked to PD2. PDts11 and PDts13 affected the formation of the neutral phosphatase only whereas PDts12 interfered with the formation of both neutral and alkaline phosphatases at 35 degrees C. The neutral phosphatase produced by the three mutants at low temperature was not more thermosensitive in vitro than the wild enzyme. Moreover, quite similar Km values were found in WT, PDts11 and PDts12 using naphthyl phosphate as a substrate. On the other hand, revertants of PD-2 and PD-3 were isolated: their neutral phosphatases could not be distinguished from the wild enzyme on the basis of their thermosensitivities and Km values for naphthyl phosphate. These results are consistent with the idea that PD2 and PD3 are regulatory genes. Other possible regulatory genes were revealed through PDts12 and PDts13 mutations.
Mol Gen Genet 1976 Nov 17
PMID:Genes involved in the regulation of the neutral phosphatase in Chlamydomonas reinhardi. 18 76

A heat-and acid-stable protein inhibitor of phosphorylase phosphatase is present in a highly purified preparation of protein inhibitor of cyclic AMP-dependent protein kinase from rabbit skeletal muscle. Although these two inhibitors have strikingly similar properties to each other, such as sensitivity to trypsin and behavior on gel permeation chromatography, they can be separated by polyacrylamide disc gel electrophoresis. This indicates that the phosphatase-inhibitory and kinase-inhibitory activities reside with different protein species. The inhibition of both the enzymes is not altered by incubating the inhibitor preparation with a general phosphoprotein phosphatase, with phosvitin kinase, or with cyclic AMP-dependent protein kinase. Inhibition of phosphorylase phosphatase is of a non-competitive type supporting the idea that the phosphatase inhibitor is not an alternative substrate for the enzyme. Inhibition of phosphatase activity is selective in that it does no occur when phosphorylated histone or phosphorylated protamine are used as substrates.
Mol Cell Biochem 1977 Apr 12
PMID:Protein inhibitors of phosphorylase phosphatase and cyclic AMP-dependent protein kinase from rabbit skeleta muscle. 19 98

The effect of three naturally occurring polyamines (putrescine, spermidine, and spermine) on the activity of rabbit skeletal muscle phosphorylase phosphatase was investigated. Only spermine significantly inhibited the enzyme. The mode of inhibition (ki value of 0.3 mM) of the phosphatase by spermine appears to be different from that caused by divalent metal ions or by other organic cations, such as arginine and lysine esters, since it is noncompetitive with respect to the substrate, phosphorylase a.
Mol Cell Biochem 1977 Apr 12
PMID:Inhibition of rabbit skeletal muscle phosphorylase phosphatase by spermine. 19 99

Using a mathematical model of carbohydrate metabolism in Dictyostelium discoideum, the kinetic expressions describing the activities of glucokinase and glucose-6-P phosphatase have been analyzed. The constraints on the kinetic mechanisms and relative activities of these two enzymes were investigated by comparing computer simulations to experimental data. The results indicated that, (1) glucose-6-P is compartmentalized with respect to the enzymes involved in glucose-60P, trehalose and glycogen metabolism, (2) a differences of approximately 0.6 mM/min in maximum specific activity of glucokinase compared to glucose-6-P phosphatase is required in order for the model to produce end product carbohydrate levels consistent with those observed experimentally, (3) the Km of glucokinase for glucose strongly influences the steady state levels of glucose in the absence of external glucose, and (4) changing the order of product removal in the reaction catalyzed by glucose-6-P phosphatase influences the level of glycogen and trehalose.
Mol Cell Biochem 1978 Apr 11
PMID:A kinetic analysis of glucokinase and glucose-6-P phosphatase in Dictyostelium. 20 18


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