Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:6.4.1.2 (acetyl-CoA carboxylase)
 2,876 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Double immunofluorescence staining showed carbonic anhydrase and glutamine synthetase in the same astrocytes. Carbamoylphosphate synthase II, which catalyzes the first committed step in pyrimidine biosynthesis, was also immunostained in astrocytes. The results suggested that in the astrocytes carbonic anhydrase and glutamine synthetase could provide the substrates, bicarbonate and glutamine, for pyrimidine biosynthesis. In the oligodendrocytes acetyl-CoA carboxylase was colocalized with carbonic anhydrase, and fatty acid synthase was immunostained in the same cell-type. As well as providing bicarbonate to initiate fatty acid synthesis in oligodendrocytes, the carbonic anhydrase in oligodendrocytes could recycle the carbon dioxide generated during this process.
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PMID:Immunostaining of carbamoylphosphate synthase II and fatty acid synthase in glial cells in rat, mouse, and hamster brains suggests roles for carbonic anhydrase in biosynthetic processes. 168 28

Acetyl-CoA carboxylase (ACC) catalyzes the rate-limiting and/or first committed step in fatty acid biosynthesis. Because fatty acids must be synthesized as components of the galactolipids and phospholipids in myelin, high specific activities of ACC would be expected in brain during myelination and in the myelinating cells, the oligondendroglia, in particular. Under reaction conditions where ACC was linear with time and protein concentration, we found specific activities of 1.7 and 3.1 nmol/min/mg protein in supernatants from forebrains and brainstems, respectively, of 20-day-old rats. In both regions, ACC declined during development, particularly after the age of 20 days. To separate forebrain into discrete fractions containing cells, membrane vesicles, and other components, without destroying the ACC, it was necessary to modify the published methods by adding citrate to the isolation medium and by omitting trypsin. A fraction which sedimented over 1.2 M sucrose showed the highest specific activities and recoveries of ACC. This fraction was rich in small cells, many of which immunostained with antibodies against galactocerebroside and carbonic anhydrase, both of which are localized in oligodendrocytes and immature glial cells. The cells in this fraction also immunostained with antibodies against ACC. The results are consistent with the hypothesis that ACC is an oligodendrocyte-associated enzyme, although it probably is not exclusive to cells of that type.
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PMID:Acetyl-CoA carboxylase in rat brain. I. Activities in homogenates and isolated fractions. 290 26

Acetyl-CoA carboxylase (ACC) catalyzes the first and, possibly, the rate-limiting step in fatty acid biosynthesis. Because oligodendrocytes must synthesize large amounts of lipid during myelination, the hypothesis was proposed that ACC might be localized in cells of that type. In sections from the brains of 12-day-old rats, ACC immunostaining was observed in glial cells in white matter and gray matter. These cells resembled carbonic anhydrase-positive oligodendrocytes at mature and immature stages of their development. Cells resembling typical oligodendrocytes were also ACC-positive in white matter from the forebrains and brainstems of 15-17 day-old-rats. In both the gray matter and the white matter of 21-day-old rats there were intensely ACC-positive cells that strongly resembled oligodendrocytes. Oligodendrocytes in the brains of adult rats also were ACC-positive. While recognizing that some ACC must be present at lower levels in other types of cells and at all ages, it was concluded that the present findings are consistent with its primary locus as the oligodendrocytes, particularly during myelination. Further, enrichment of ACC and carbonic anhydrase in the same type of cell suggested that carbonic anhydrase might serve in providing a substrate, bicarbonate, to be utilized by ACC.
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PMID:Acetyl-CoA carboxylase in rat brain. II. Immunocytochemical localization. 290 27

The membrane-associated human isozyme of carbonic anhydrase, hCA IV, has been investigated for its interaction with anion inhibitors, for the CO(2) hydration reaction catalyzed by this enzyme. Surprisingly, halides were observed to act as potent hCA IV inhibitors, with inhibition constants in the range of 70-90 microM, although most of these ions, and especially fluoride, the best hCA IV inhibitor among the halides, are weak inhibitors of other isozymes, such as hCA I, II and V. The metal poisons cyanate, cyanide and hydrogen sulfide were weaker hCA IV inhibitors (K(i)'s in the range of 0.6-3.9 mM), whereas thiocyanate, azide, nitrate and nitrite showed even weaker inhibitory properties (K(i)'s in the range of 30.8-65.1 mM). Sulfate was a good hCA IV inhibitor (K(i) of 9 mM), although it is a much weaker inhibitor of isozymes I, II, V and IX. Excellent hCA IV inhibitory properties showed sulfamic acid, sulfamide, phenylboronic acid and phenylarsonic acid, with K(i)'s in the range of 0.87-0.93 microM, whereas their affinities for the other investigated isozymes were in the millimolar range. The interaction of some anions with the mitochondrial isozyme hCA V has also been investigated for the first time here. It has been observed that among all these isozymes, hCA V has the lowest affinity for bicarbonate and carbonate (K(i)'s in the range of 82-95 mM), which may represent an evolutionary adaptation of this isozyme to the rather alkaline environment (pH 8.5) within the mitochondria, where hCA V plays important functions in some biosynthetic reactions involving carboxylating enzymes (pyruvate carboxylase and acetyl coenzyme A carboxylase). There are important differences of affinity for anions between the two membrane-associated isozymes, hCA IV and hCA IX.
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PMID:Carbonic anhydrase inhibitors: inhibition of the membrane-bound human isozyme IV with anions. 1550 Oct 38

The NCE103 gene of the yeast Saccharomyces cerevisiae encodes a CA (carbonic anhydrase) that catalyses the interconversion of CO2 and bicarbonate. It has previously been reported that nce103 null mutants require elevated CO2 concentrations for growth in batch cultures. To discriminate between 'sparking' effects of CO2 and a CO2 requirement for steady-state fermentative growth, we switched glucose-limited anaerobic chemostat cultures of an nce103 null mutant from sparging with pure CO2 to sparging with nitrogen gas. This switch resulted in wash-out of the biomass, demonstrating that elevated CO2 concentrations are required even under conditions where CO2 is produced at high rates by fermentative sugar metabolism. Nutritional analysis of the nce103 null mutant demonstrated that growth on glucose under a non-CO2-enriched nitrogen atmosphere was possible when the culture medium was provided with L-aspartate, fatty acids, uracil and L-argininine. Thus the main physiological role of CA during growth of S. cerevisiae on glucose-ammonium salts media is the provision of inorganic carbon for the bicarbonate-dependent carboxylation reactions catalysed by pyruvate carboxylase, acetyl-CoA carboxylase and CPSase (carbamoyl-phosphate synthetase). To our knowledge, the present study represents the first full determination of the nutritional requirements of a CA-negative organism to date.
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PMID:Carbonic anhydrase (Nce103p): an essential biosynthetic enzyme for growth of Saccharomyces cerevisiae at atmospheric carbon dioxide pressure. 1594 16