Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation最新文献_第7页

The enzymes of lactose biosynthesis I. Purification and properties of UDPG pyrophosphorylase from bovine mammary tissue 乳糖生物合成酶1 .牛乳腺组织中UDPG焦磷酸化酶的纯化及性质

Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation Pub Date : 1966-10-17 DOI: 10.1016/0926-6593(66)90145-7

V.S. Steelman, K.E. Ebner

引用次数: 15

Electron-transfer mechanism associated with fatty acid desaturation catalyzed by liver microsomes 肝微粒体催化脂肪酸去饱和的电子转移机制

Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation Pub Date : 1966-10-17 DOI: 10.1016/0926-6593(66)90137-8

Nozomu Oshino, Yoshio Imai, Ryo Sato

{"title":"Electron-transfer mechanism associated with fatty acid desaturation catalyzed by liver microsomes","authors":"Nozomu Oshino, Yoshio Imai, Ryo Sato","doi":"10.1016/0926-6593(66)90137-8","DOIUrl":"10.1016/0926-6593(66)90137-8","url":null,"abstract":"<div>Suitable assay conditions are described for the NADPH-dependent oxidative desaturation of stearyl-CoA by rat-liver microsomes.NADH is an even more effective electron donor than NADPH. Ascorbate at high concentrations also acts as a donor, but with low efficiency. Unlike the NADPH-dependent drug hydroxylations, the desaturation reaction does not seem to involve the microsomal hemoprotein P-450. Instead, a hitherto unknown cyanide-sensitive factor appears to be involved in the desaturation mechanism, regardless of the electron donors employed. The microsomal NADPH-specific flavoprotein with a cytochrome <math><mtext>c</mtext></math> reductase activity seems to participate, not only in the NADPH-dependent drug hydroxylations, but also in the NADPH-supported desaturation. Microsomal oxidation of methanol, which requires NADPH and is sensitive to cyanide, appears to be catalyzed by a mechanism which differs from that involved in desaturation.On the basis of these findings the electron-transfer mechanisms associated with these microsomal reactions are discussed.</div>","PeriodicalId":100160,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation","volume":"128 1","pages":"Pages 13-28"},"PeriodicalIF":0.0,"publicationDate":"1966-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6593(66)90137-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15489439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 234

Isoenzyme der malatdehydrogenase und ihre regulation in Saccharomyces cerevisiae 乙醚酶以及为糖衣套餐定制

Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation Pub Date : 1966-10-17 DOI: 10.1016/0926-6593(66)90142-1

Irene Witt, Rainer Kronau, Helmut Holzer

{"title":"Isoenzyme der malatdehydrogenase und ihre regulation in Saccharomyces cerevisiae","authors":"Irene Witt, Rainer Kronau, Helmut Holzer","doi":"10.1016/0926-6593(66)90142-1","DOIUrl":"10.1016/0926-6593(66)90142-1","url":null,"abstract":"<div><ul><li>1.1. From Saccharomyces cerevisiae, incubated on a glucose-free medium with acetate as the only carbon source, two different malate dehydrogenases (l-malate: NAD+ oxidoreductase, EC 1.1.1.37) have been isolated by DEAE-cellulose ion-exchange chromatography. One of these enzymes was only found in the mitochondria and is called enzyme A or m-malate dehydrogenase; the other enzyme was found in the extramitochondrial c-space and is called enzyme B or c-malate dehydrogenase. At present it cannot be decided whether m-malate dehydrogenase also exists in the c-space or leaks when the mitochondria are injured.</li><li>2.2. The reaction velocity plotted against the concentration of oxaloacetic acid showed a characteristic substrate inhibition in the case of m-malate dehydrogenase In contrast, c-malate dehydrogenase showed no substrate inhibition. This difference corresponds to the behaviour of m-malate dehydrogenase and c-malate dehydrogenase from liver.</li><li>3.3. In yeast grown on glucose only m-malate dehydrogenase could be found, but after incubating the cells on acetate as the sole carbon source, both m-malate dehydrogenase and c-malate dehydrogenase were found. In reference to earlier experiments concerning the regulation of malate dehydrogenase activity in yeast, it is concluded that a repression of c-malate dehydrogenase synthesis by glucose occurs. This regulating mechanism is useful for the cell, because in the glycoxylate cycle c-malate dehydrogenase participates in the gluconeogenesis from acetate or ethanol. This enzyme is not necessary when glucose is in the medium.</li></ul></div>","PeriodicalId":100160,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation","volume":"128 1","pages":"Pages 63-73"},"PeriodicalIF":0.0,"publicationDate":"1966-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6593(66)90142-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85760000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 84

Regulation of citrate synthase activity in Escherichia coli 大肠杆菌中柠檬酸合成酶活性的调控

Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation Pub Date : 1966-10-17 DOI: 10.1016/0926-6593(66)90166-4

P.D.J. Weitzman

引用次数: 80

Kinin-forming enzyme (kininogenin) in homogenates of rat kidney 大鼠肾匀浆中的激肽形成酶(激肽原)

Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation Pub Date : 1966-10-17 DOI: 10.1016/0926-6593(66)90150-0

Ivan F. Carvalho, Carlos R. Diniz

引用次数: 28

Purification and properties of ribonuclease N1, an extracellular ribonuclease of Neurospora crassa 粗神经孢子虫胞外核糖核酸酶N1的纯化及性质研究

Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation Pub Date : 1966-10-17 DOI: 10.1016/0926-6593(66)90168-8

Norie Takai, Tsuneko Uchida, Fujio Egami

引用次数: 19

Conformation of aspergillopeptidase a in aqueous solution 曲霉肽酶a在水溶液中的构象

Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation Pub Date : 1966-10-17 DOI: 10.1016/0926-6593(66)90149-4

Eiji Ichishima, Fumihiko Yoshida

{"title":"Conformation of aspergillopeptidase a in aqueous solution","authors":"Eiji Ichishima, Fumihiko Yoshida","doi":"10.1016/0926-6593(66)90149-4","DOIUrl":"10.1016/0926-6593(66)90149-4","url":null,"abstract":"<div>The conformation of the extracellular acid proteinase of Aspergillus saitoi (aspergillopeptidase A, EC 3.4.4.17) has been investigated in aqueous solution. The optical rotation, <math><mtext>[α]</mtext><msub><mi></mi><mn><mtext>D</mtext></mn></msub></math>, was −35°. The optical rotatory dispersion constant, <math><mtext>λ</mtext><msub><mi></mi><mn><mtext>c</mtext></mn></msub></math>, was 207 mμ, and the Moffitt-Yang parameter, <math><mtext>b</mtext><msub><mi></mi><mn>0</mn></msub></math>, was zero. The <math><mtext>−a</mtext><msub><mi></mi><mn>0</mn></msub></math> value in the Moffitt-Yang parameter or levorotation of the aspergillopeptidase. A molecule increased markedly in the presence of urea, while the value of <math><mtext>b</mtext><msub><mi></mi><mn>0</mn></msub></math> remained unchanged. This finding indicates the absence of a helical conformation.The infrared result indicates that the deuterium-exchanged aspergillopeptidase A exists in the antiparallel β structure. The location of an amide I band at 1632 cm−1 has been observed. The spectrum has shown the presence of a weak band around 1685 cm−1.The location of the single tryptophan residue in aspergillopeptidase A is discussed.</div>","PeriodicalId":100160,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation","volume":"128 1","pages":"Pages 130-135"},"PeriodicalIF":0.0,"publicationDate":"1966-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6593(66)90149-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17043504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 13

Inactivation of citrate lyase by oxaloacetate and its structural analogues 草酰乙酸及其结构类似物对柠檬酸裂解酶的失活作用

Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation Pub Date : 1966-10-17 DOI: 10.1016/0926-6593(66)90152-4

Robert Eisenthal, S.S. Tate, S.P. Datta

{"title":"Inactivation of citrate lyase by oxaloacetate and its structural analogues","authors":"Robert Eisenthal, S.S. Tate, S.P. Datta","doi":"10.1016/0926-6593(66)90152-4","DOIUrl":"10.1016/0926-6593(66)90152-4","url":null,"abstract":"<div><ul><li>1.1. The inactivation of citrate lyase (citrate-oxaloacetate lyase, EC 4.1.3.6) by oxaloacetate has been investigated.</li><li>2.2. Studies of the pH profiles of inactivation at pH 7–9 with varying total oxaloacetate and magnesium concentrations show that the magnesium complexes of enolic oxaloacetate are involved.</li><li>3.3. The inhibitory effects of the following structural analogues of the keto and enol forms of oxaloacetate were examined: l-malate, α,α-dimethyloxaloacetate, tartronate, α,α-difluorooxaloacetate, pyruvate, ketomalonate, and isomalate. These results, and the effect of other divalent metal cations, indicate that the site of the inactivation is identical with the active site for citrate cleavage.</li><li>4.4. The inactivation is irreversible and is time and concentration dependent. Free oxaloacetate does not inactivate the enzyme.</li><li>5.5. The inactivation phenomenon has high structural specificity, requiring a straight-chain, four-carbon dicarboxylic acid with an ionisable α-hydroxy group, and the presence of a divalent metal cation.</li></ul></div>","PeriodicalId":100160,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation","volume":"128 1","pages":"Pages 155-164"},"PeriodicalIF":0.0,"publicationDate":"1966-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6593(66)90152-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17043507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

The inhibition of lemon citrate-condensing enzyme by ATP ATP对柠檬柠檬酸盐凝聚酶的抑制作用

Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation Pub Date : 1966-10-17 DOI: 10.1016/0926-6593(66)90158-5

E. Bogin, A. Wallace

引用次数: 31

Purification of hog renin by column chromatography 猪肾素的柱层析纯化

Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation Pub Date : 1966-10-17 DOI: 10.1016/0926-6593(66)90159-7

George D. Maier, Winfield S. Morgan

引用次数: 6