Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:2.7.1.1 (hexokinase)
5,274 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. Procedures were developed for the extraction and assay of glycolytic enzymes from the epididymis and epididymal spermatozoa of the rat. 2. The epididymis was separated into four segments for analysis. When rendered free of spermatozoa by efferent duct ligation, regional differences in enzyme activity were apparent. Phosphofructokinase, glycerol phosphate dehydrogenase and glucose 6-phosphate dehydrogenase were more active in the proximal regions of the epididymis, whereas hexokinase, lactate dehydrogenase and phosphorylase were more active in the distal segment. These enzymes were less active in the epididymis of castrated animals and less difference was apparent between the proximal and distal segments. However, the corpus epididymidis from castrated rats had lower activities of almost all enzymes compared with other epididymal segments. 3. Spermatozoa required sonication to obtain satisfactory enzyme release. Glycolytic enzymes were more active in spermatozoa than in epididymal tissue, being more than 10 times as active in the case of hexokinase, phosphoglycerate kinase and phosphoglycerate mutase. 4. The specific activities of a number of enzymes in the epididymis were dependent on the androgen status of the animal. These included hexokinase, phosphofructokinase, aldolase, glyceraldehyde phosphate dehydrogenase, phosphoglycerate kinase, pyruvate kinase, glycerol phosphate dehydrogenase, glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and phosphorylase. 5. The caput and cauda epididymidis differed in the extent to which enzyme activities changed in response to an altered androgen status. The most notable examples were hexokinase, phosphofructokinase, aldolase, phosphoglycerate kinase, 6-phosphogluconate dehydrogenase and phosphorylase.
...
PMID:Activity and androgenic control of glycolytic enzymes in the epididymis and epididymal spermatozoa of the rat. 18 56

The adaptive responses of gastrointestinal enzymes, glucose tolerance, and plasma insulin to diet, folic acid, and insulin of five obese adult-onset diabetic patients were studied before and after a 30-day fast. Their data were compared to the adaptive responses of gastrointestinal enzymes to diet, folic acid, and insulin of 15 normal male volunteer subjects, ages 18 to 24. Each group during each testing period received a carbohydrate diet (50% calories as carbohydrate consisting of 1/2 glucose and 1/2 fructose) and a noncarbohydrate diet (70% of calories as corn oil and 30% as sodium caseinate) each without and with folic acid (5 mg three times per day). The effect of insulin was studied only on the carbohydrate diet plus folic acid. Our data demonstrate that obese adult-onset diabetic patients have an impaired adaptive response of jejunal carbohydrate-metabolizing enzyme activities (hexokinase, pyruvate kinase, fructose-1-6-diphosphate aldolase, fructosediphosphatase) to dietary carbohydrate, oral folic acid, and insulin when compared to normal subjects and nondiabetic obese patients. Following a 30-day fast, the obese diabetic patients showed an improvement in glucose tolerance, hyperinsulinemia, and the adaptive response of the jejunal carbohydrate-metabolizing enzyme activities to dietary carbohydrate, folic acid, and insulin. The greatest improvement in the adaptive response of the jejunal enzyme activities occurred on the carbohydrate diet.
...
PMID:Improvement in jejunal enzyme adaptation in obese adult-onset diabetic patients following a 30-day fast. 18 94

A surgical specimen of solitary, encapsulated tumor tissue obtained from a 52-year-old male, diagnosed histologically as well-differentiated hepatocellular carcinoma (Grade II, Edmondson and Steiner) with liver cirrhosis, Type A' (and B is some parts), was found to have a supernormal level of pyruvate kinase Type L and subnormal level of Type M2; the activities (units/mg protein) being 1.21 and 0.12 respectively. The resulting isozyme pattern was apparently "superdifferentiated" as compared with those of not only the tumor-bearing, cirrhotic liver (Type L, 0.19; Type M2, 0.67) but also the normal liver (Type L, 0.47+/-0.05; Type M2, 0.18+/-0.02). The electrophoretic and kinetic properties of the type L isozyme were identical with those of the cirrhotic host liver and a non-cirrhotic control liver. Other enzyme levels in the hepatoma tissue were as follows: Glucose-6-phosphatase, norma; fructose-1,6-bisphosphatase, reduced; glucokinase, absent; and hexokinase Types I and III, and glucose-6-phosphate dehydrogenase, slightly increased. The serum alpha-fetoprotein level was 95 ng/ml. The whole enzyme profile is consistent with the minimal deviation hepatomas in rats. The results were compared with those of other human hepatomas, and the mechanisms of disordered regulation in hepatoma gene expression were discussed.
...
PMID:A case of minimal deviation hepatoma in man with elevated liver-type pyruvate kinase isozyme. 19 53

Reaction of ADP with hexamethylene diisocyanate in hexamethylphosphoramide followed by treatment in an acidic medium afforded three new adenine nucleotide analogues, N6-[N-(6-aminohexyl)carbamoyl]-ADP, N6-[N-(6-aminohexyl)carbamoyl]-ATP, and N6-[N-(6-aminohexyl)carbamoyl]-AMP in yields of 13%, 12% and 17%, respectively. The occurrence of the ATP analogue may be interpreted in terms of the equilibrium, 2ADP = ATP + AMP. Coenzymic activities of the ADP analogue against acetate kinase and pyruvate kinase were 82% and 20%, respectively, relative to ADP and those of the ATP analogue against hexokinase and glycerokinase were 63% and 87%, respectively, relative to ATP. These analogues were bound to CNBr-activated soluble dextran through their terminal amino group to give an immobilized ADP and an immobilized ATP, each of which was recycled in a system comprising acetate kinase and hexokinase, and when placed in a membrane reactor together with the enzymes, functioned as an immobilized coenzyme continuously yielding glucose 6-phosphate. A series of chemically defined affinity adsorbents were obtained by coupling these analogues to CNBr-activated Sepharose, and were used to separate the enzymes in a mixture of hexokinase, pyruvate kinase, phosphoglycerate kinase, lactate dehydrogenase, and alcohol dehydrogenase.
...
PMID:Preparation of N6-[N-(6-aminohexyl) carbamoyl]-adenine nucleotides and their application to coenzymically active immobilized ADP and ATP, and affinity adsorbents. 19 56

Various enzyme activities involved in the active transport system, glycolysis, and digestion were assayed in various parts of the gastrointestinal tracts of germfree, conventional, and gnotobiotic rats associated with indigenous bacteria. The activity levels of alkaline phosphatase, glucose 6-phosphatase, adenosine triphosphatase, and disaccharidases in the upper small intestine were highest in all parts of the gastrointestinal tracts of various kinds of gnotobiotic, conventional, and germfree rats. Alkaline phosphatase, glucose 6-phosphatase, and adenosine triphosphatase activities in the upper small intestine of germfree rats were, respectively, 2.3-, 2.9-, and 1.7-fold higher than those in conventional rats. Similar to the results of these enzymes, sucrase, maltase, trehalase, and lactase activities in the upper small intestine of germfree rats were, respectively, 1.6-, 1.5-, 2.3-, and 1.8-fold higher than those in conventional rats. In various gnotobiotic rats, enzyme activity levels were intermediate between those in germfree and conventional rats. These findings suggest that those enzymatic activities are strongly depressed by the association with the indigenous microorganisms in the epithelial mucosa of the upper small intestine of rats. The levels of pyruvate kinase, hexokinase, and lactate dehydrogenase activities were highest, respectively, in the stomach, cecum, and the upper small intestine and cecum in all parts of the gastrointestinal tracts in various kinds of gnotobiotic, conventional, and germfree rats. It was also shown that six kinds of gastrointestinal bacteria, including lactobacilli, significantly depressed the enzyme activity levels to levels between those of the germfree and conventional rats in the upper small intestine of gnotobiotic rats.
...
PMID:Intestinal enzyme activities in germfree, conventional, and gnotobiotic rats associated with indigenous microorganisms. 20 6

An ultramicrochemical technique has been adapted to the evolution of enzyme profiles within individual human mammary tumors. Tandem observation of adjacent stained and lyophilized sections permitted dissection of microgram quantities of freeze-dried material within confirmed regions of malignancy. Enzymes frequently monitored to examine glycolytic, respiratory, and metastatic capacity were microanalyzed successfully: lactic dehydrogenase (LDH), phosphoglucose isomerase (PGI), malate dehydrogenase (MDH), acid phosphatase (AP), aldolase (ALD), glucose-6-phosphate dehydrogenase (G6PDH), pyruvate kinase (PK), alpha-glycerophosphate dehydrogenase (alpha-GOPDH), hexokinase (HK), and phosphofructokinase (PRK). All enzyme activities were higher in infiltrating ductal carcinomas than in fibroadenomas. Extracts of tumor cells mixed in varying proportions with brain or muscle extracts of rat evidenced no modification of expected activity. The technical adaptation described provided a sensitive methodology to resolve problems of relication, profile analysis, sample quantity, and selectivity within heterogeneous tissues.
...
PMID:Application of a microchemical technique to the elucidation of enzyme activity profiles within single human mammary tumors. 20 41

The 2-[18O]phosphorothioate of D-glycerate, chiral at phosphorus, was prepared. The chiral phosphoryl group was transferred enzymically to ADP [by using enolase and pyruvate kinase (ATP:pyruvate 2-O-phosphotransferase; EC 2.7.1.40)] resulting in the synthesis of adenosine 5'-O-([gamma-18O],gamma-thio)triphosphate. This labeled ATP was used as a thiophosphoryl group donor in the reactions catalyzed by glycerol kinase (ATP:glycerol 3-phosphotransferase; EC 2.7.1.30) and by hexokinase (ATP:D-hexose 6-phosphotransferase; EC 2.7.1.1). The product from the latter (glucose 6-phosphorothioate) was converted enzymically into glycerol phosphorothioate. Determination of the relative configurations and diastereoisomeric purities of the samples of glycerol phosphorothioate demonstrates that all three phosphokinases (pyruvate kinase, glycerol kinase, and hexokinase) transfer the thiophosphoryl group with complete stereospecificity, and further shows that these reactions follow an identical stereochemical course.
...
PMID:Adenosine 5'-O-([gamma-18O]gamma-thio)triphosphate chiral at the gamma-phosphorus: stereochemical consequences of reactions catalyzed by pyruvate kinase, glycerol kinase, and hexokinase. 20 59

During the first 72 h after 67% partial hepatectomy of female Wistar rats (160 g) the specific activities [mumol X min-1 X (g liver)-1] of the glucogenic glucose-6-phosphatase and fructose-bisphosphatase and of the glycolytic hexokinase and 6-phosphofructokinase remained essentially constant. However, the activity of the glycolytic pyruvate kinase (L- plus M2-type) was decreased slightly and that of glucokinase was decreased markedly to below 30%, while the glucogenic phosphoenolpyruvate carboxykinase was increased to over 200%. Between 10 and 40 h after partial hepatectomy, when the proliferation started in the periportal area, a shift of the glucogenic glucose-6-phosphatase-rich zone from its normal periportal to an intermediate or even perivenous position was observed histochemically. After 48 h, when the proliferation was no longer restricted to the periportal zone, the normal glucose-6-phosphatase zonation (as before partial hepatectomy) was restored. Glycogen was degraded rapidly during the first 4 h after operation; it was later repeatedly resynthesized and degraded in correlation with the feeding rhythm of the animals. The zonation of glycogen metabolism was in accord with the observed zonation of glucose-6-phosphatase.
...
PMID:Increase of the gluconeogenic and decrease of the glycolytic capacity of rat liver with a change of the metabolic zonation after partial hepatectomy. 21 1

We report the synthesis of adenosine [gamma-(S)-16O,17O,18O]triphosphate, an isotopically labeled species of ATP that is chiral at the gamma-phosphoryl group, the configuration of which has been confirmed by independent stereochemical analysis. This molecule has been used as a substrate in the reactions catalyzed by glycerol kinase and by acetate kinase. The resulting samples of isotopically labeled sn-glycerol 3-phosphate and of acetyl phosphate have been used as substrates in the alkaline phosphatase mediated transfer of the chiral phosphoryl groups to (S)-propane-1,2-diol, whence the configuration at phosphorus has been determined [Abbott, S. J., Jones, S. R., Weinman, S. A., & Knowles, J. R. (1978) J. Am. Chem. Soc. 100, 2558]. It is shown that glycerol kinase and acetate kinase (and, by virtue of an earlier correlation, pyruvate kinase and hexokinase) proceed by pathways that result in inversion of the configuration at phosphorus. The sterochemical approach provides an access to the otherwise cryptic events that are involved in phosphoryl-group transfer within the ternary complexes of these kinases and their substrates.
...
PMID:Stereochemical course of phosphokinases. The use of adenosine [gamma-(S)-16O,17O,18O]triphosphate and the mechanistic consequences for the reactions catalyzed by glycerol kinase, hexokinase, pyruvate kinase, and acetate kinase. 22 19

Hyperinsulinemia was produced in fetal rhesus monkeys for 21 days in the last third of gestation by subcutaneous pork insulin injected at 19 U a day. Plasma insulin concentrations in treated fetuses (N = 4) were 3525 microU/ml. There was no difference in paired pre- and post-treatment fetal plasma glucose concentration. Activity of the hepatic enzymes that promote glucose utilization (glucokinase and hexokinase) and glycolysis (phosphofructokinase, pyruvate kinase, and pyruvate dehydrogenase) was unaffected. Similarly, glycogen metabolism enzymes (active and inactive synthase and phosphorylase) were unaltered. Two gluconeogenic enzymes (PEPCK and glucose-6-phosphatase) were diminished in the treated group compared with controls. Fetal hyperinsulinemia enhanced lipogenic and NADPH-producing enzyme activities, as evidenced by a twofold increase in fatty acid synthase and in citrate cleavage enzyme activity. Malic enzyme was absent. Hyperinsulinemia with euglycemia (1) increases the activity of enzymes that participate in lipogenesis, (2) decreases some of those controlling gluconeogenesis, and (3) has no effect on the enzymes of glycolysis.
...
PMID:Chronic hyperinsulinemia in the fetal rhesus monkey: effects on hepatic enzymes active in lipogenesis and carbohydrate metabolism. 22 50


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>

---