International Journal of Biochemistry最新文献

{"title":"Interactions of Adriamycin aglycones with mitochondria may mediate Adriamycin cardiotoxicity","authors":"Patricia M. Sokolove","doi":"10.1016/0020-711X(94)90176-7","DOIUrl":"10.1016/0020-711X(94)90176-7","url":null,"abstract":"<div><p>Adriamycin and related anthracyclines are potent oncolytic agents, the clinical utility of which is limited by severe cardiotoxicity. Aglycone metabolites of Adriamycin (5–20 μM) induce a Ca²⁺-dependent increase in the permeability of the inner mitochondrial membrane of both heart and liver mitochondria to small (&lt; 1500 Da) solutes; this phenomenon is accompanied by release of mitochondrial Ca²⁺, mitochondrial swelling, collapse of the membrane potential, oxidation of mitochondrial pyridine nucleotides [NAD(P)H], uncoupling, and a transition from the condensed to the orthodox conformation and is inhibited by ATP, dithiothreitol, the immunosuppressant cyclosporin A, and the ubiquitous polyamine spermine. Aglycones also modify mitochondrial sulfhydryl groups and induce a Ca²⁺ independent oxidation of mitochondrial NAD(P)H which appears to reflect electron transport from NADH to oxygen, mediated by the aglycones and resulting in the production of Superoxide (O₂⁻). Selenium deficiency and butylated hydroxytoluene inhibit aglycone-induced Ca²⁺ release from liver, but not heart, mitochondria, suggesting that the interactions of the aglycones with mitochondria diner in these two tissues. It can be proposed that the effects of Adriamycin aglycones on heart mitochondria are responsible for the cardiotoxicity of the parent drug.</p></div>","PeriodicalId":13733,"journal":{"name":"International Journal of Biochemistry","volume":"26 12","pages":"Pages 1341-1350"},"PeriodicalIF":0.0,"publicationDate":"1994-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-711X(94)90176-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18888612","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}

{"title":"List of contents and author index volume 26, 1994","authors":"","doi":"10.1016/0020-711X(94)90186-4","DOIUrl":"https://doi.org/10.1016/0020-711X(94)90186-4","url":null,"abstract":"","PeriodicalId":13733,"journal":{"name":"International Journal of Biochemistry","volume":"26 12","pages":"Pages I-XV"},"PeriodicalIF":0.0,"publicationDate":"1994-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-711X(94)90186-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136411897","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}

{"title":"Biochemical characterization of hemorrhagic toxin from crotalus viridis viridis (prairie rattlesnake) venom","authors":"Yumiko Komori,&nbsp;Toshiaki Nikai,&nbsp;Chie Sekido,&nbsp;Minako Fuwa,&nbsp;Hisayoshi Sugihara","doi":"10.1016/0020-711X(94)90185-6","DOIUrl":"10.1016/0020-711X(94)90185-6","url":null,"abstract":"<div><p>Hemorrhage, necrosis and edema are some of the effects often observed following snake bites. This paper reports studies on the isolation and biological properties of hemorrhagic toxin from <em>Crotalus viridis viridis</em> (Prairie rattlesnake) venom. A hemorrhagic toxin was isolated from <em>C. v. viridis</em> venom by Sephadex G-50, DEAE-Sephacel and Q-Sepharose column chromatographies.</p><p>The hemorrhagic toxin from <em>C. v. viridis</em> venom was shown to be homogenous as demonstrated by a single band on polyacrylamide gel electrophoresis and immunodiffusion. Its molecular weight was approximately 54,000 dallons, and it contained 471 amino acid residues. The toxin possessed hemorrhagic activity with a minimum hemorrhagic dose (MHD) of 0.11 μ g, and hydrolytic activity on dimethylcasein, casein, azocasein, azoalbumin, azocoll and hide powder azure. Hemorrhagic and casein hydrolytic activities were inhibited by EDTA, <em>o</em>-phenanthroline or dithiothreitol. The toxin contained 1 mole of zinc per mole of protein and zinc is essential for both hemorrhagic and proteolytic activities. Hemorrhagic toxin possessed hydrolytic activity on the B-chain of insulin, which cleaves His(5)-Leu(6), His(10)-Leu(11), Ala(14)-Leu(15), Tyr(16)-Leu(17) and Phe(24)-Phe(25) bonds. This toxin also hydrolyzed Aα and Bβ chains of fibrinogen. Intramuscular injections of hemorrhagic toxin caused an increase of creatine phosphokinase activity in mice serum from 50.3 mU/ml to 1133 mU/ml. A toxin isolated from <em>C. v. viridis</em> venom was shown to have strong hemorrhagic activity. Partial characterization is reported for this major hemorrhagic toxin in <em>C. v. viridis</em> venom.</p></div>","PeriodicalId":13733,"journal":{"name":"International Journal of Biochemistry","volume":"26 12","pages":"Pages 1411-1418"},"PeriodicalIF":0.0,"publicationDate":"1994-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-711X(94)90185-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18887239","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}

{"title":"Two nuclear-coded subunits of mitochondrial complex I are similar to different domains of a bacterial formate hydrogenlyase subunit","authors":"Arnaldo Videira,&nbsp;Jorge E. Azevedo","doi":"10.1016/0020-711X(94)90182-1","DOIUrl":"10.1016/0020-711X(94)90182-1","url":null,"abstract":"<div><p>A computer comparison of protein sequences revealed similarity between the 30.4 kDa subunit of complex I from the fungus <em>Neurospora crassa</em> and the ORF5 subunit of formate hydrogenlyase from <em>Escherichia coli</em>. The ORF5 protein was previously known to be homologous to the 49 kDa component of the mitochondrial enzyme. We show that the 30.4 kDa corresponds to the N-terminal part while the 49 kDa subunit corresponds to the C-terminal portion of the bacterial protein. Thus, this bacterial protein represents a fusion of the two mitochondrial polypeptides suggesting that the two complex I genes arose from a single ancestor. Our results indicate that the 30.4 kDa and 49 kDa subunits are part of a structural and functional unit in complex I.</p></div>","PeriodicalId":13733,"journal":{"name":"International Journal of Biochemistry","volume":"26 12","pages":"Pages 1391-1393"},"PeriodicalIF":0.0,"publicationDate":"1994-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-711X(94)90182-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18888618","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}

{"title":"Editorial Announcement","authors":"","doi":"10.1016/0020-711X(94)90173-2","DOIUrl":"https://doi.org/10.1016/0020-711X(94)90173-2","url":null,"abstract":"","PeriodicalId":13733,"journal":{"name":"International Journal of Biochemistry","volume":"26 12","pages":"Page iii"},"PeriodicalIF":0.0,"publicationDate":"1994-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-711X(94)90173-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136414716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inhibition of porphobilinogenase by porphyrins in Saccharomyces cerevisiae","authors":"Lidia Susana Araujo,&nbsp;Maria Elisa Lombardo,&nbsp;Alcira M. Del C. Batlle","doi":"10.1016/0020-711X(94)90180-5","DOIUrl":"10.1016/0020-711X(94)90180-5","url":null,"abstract":"<div><p>The biosynthesis of uroporphyrinogen III, the precursor of hemes, chlorophylls, corrins and related structures, is catalyzed by the porphobilinogenase system (PBGase), a complex of two enzymes, PBG-Deaminase (PBG-D) and Isomerase. Although the separate enzymes have been studied in some detail less work has been performed on the properties of the complex.</p><p>In this study the kinetic behaviour of the enzyme PBGase in a normal yeast strain, D273-10B, and its derivative B231 has been investigated. Uroporphyrinogen formation was linear with time up to 2 hr at 37°C. The enzyme complex shows classical Michaelis-Menten kinetics. From the double reciprocal plots kinetic parameters were estimated for PBGase and PBG-D.</p><p>Porphyrins were found to be competitive inhibitors with respect to porphobilinogen (PBG) and these compounds appeared to act as inhibitors by forming dead-end complexes with the free enzyme. 5-Aminolevulinic acid (ALA) also inhibited PBGase and this inhibition was overcome by addition of levulinic acid (2μM). These results indicate that ALA, is not an inhibitor but acts through its conversion into porphyrins which are the true inhibitors.</p></div>","PeriodicalId":13733,"journal":{"name":"International Journal of Biochemistry","volume":"26 12","pages":"Pages 1377-1381"},"PeriodicalIF":0.0,"publicationDate":"1994-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-711X(94)90180-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18888616","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}

{"title":"E1/E2 type cation transport ATPases: Evidence for transient associations between protomers","authors":"Alexander A. Boldyrev ,&nbsp;Peter J. Quinn","doi":"10.1016/0020-711X(94)90174-0","DOIUrl":"10.1016/0020-711X(94)90174-0","url":null,"abstract":"<div><p>E1/E2 type cation transport ATPases are known to exist in different conformeric states. Recent evidence characterizing these conformers in membrane is reviewed. A consensus view is proposed in which E2 conformers tend to form oligomeric complexes by lateral association between monomeric protomers and El conformers exhibit the opposite behaviour. It is suggested that transient associations between monomers during cation pump cycles may be a common feature of the ion translocation mechanism under physiological conditions.</p></div>","PeriodicalId":13733,"journal":{"name":"International Journal of Biochemistry","volume":"26 12","pages":"Pages 1323-1331"},"PeriodicalIF":0.0,"publicationDate":"1994-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-711X(94)90174-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18888073","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}

{"title":"Calmodulin and cAMP dependent synaptic vesicle protein phosphorylation in rat cortex following lead exposure","authors":"Rajat Sandhir,&nbsp;Kiran Dip Gill","doi":"10.1016/0020-711X(94)90181-3","DOIUrl":"10.1016/0020-711X(94)90181-3","url":null,"abstract":"<div><p>The effect of <em>in vivo</em> and <em>in vitro</em> lead exposure on calmodulin and cAMP dependent synaptic vesicle protein phosphorylation has been investigated. Lead could enhance calmodulin activity following <em>in vitro</em> and <em>in vivo</em> lead exposure. The calmodulin dependent synaptic vesicle protein phosphorylation was enhanced following <em>in vivo</em> and <em>in vitro</em> lead exposure resulting in the depletion of the neurotransmitters norepinephrine and acetylcholine. The cAMP dependent synaptic vesicle protein phosphorylation was inhibited by both <em>in vitro</em> and <em>in vivo</em> lead treatment. The results suggest that lead adversely affects synaptic vesicle protein phosphorylation and this may ultimately effect synaptic functions.</p></div>","PeriodicalId":13733,"journal":{"name":"International Journal of Biochemistry","volume":"26 12","pages":"Pages 1383-1389"},"PeriodicalIF":0.0,"publicationDate":"1994-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-711X(94)90181-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18888617","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}

{"title":"Mechanisms of initiating calcification. ATP-stimulated Ca- and Pi-depositing activity of isolated matrix vesicles","authors":"Howard H.T. Hsu","doi":"10.1016/0020-711X(94)90177-5","DOIUrl":"10.1016/0020-711X(94)90177-5","url":null,"abstract":"","PeriodicalId":13733,"journal":{"name":"International Journal of Biochemistry","volume":"26 12","pages":"Pages 1351-1356"},"PeriodicalIF":0.0,"publicationDate":"1994-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-711X(94)90177-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18888613","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}

{"title":"Selective inactivation of muscarinic receptor subtypes","authors":"Richard M. Eglen,&nbsp;Helen Reddy,&nbsp;Nikki Watson","doi":"10.1016/0020-711X(94)90178-3","DOIUrl":"10.1016/0020-711X(94)90178-3","url":null,"abstract":"<div><p>Muscarinic receptors exist in multiple subtypes, denoted as M₁, M₂ M₃ and M₄, encoded by four distinct but related genes. A fifth gene product, m5, has also been predicted although this sequence awaits a pharmacological equivalent. Many tissues express more than one muscarinic receptor subtype, which may couple to different intracellular effectors and thus have different physiological roles. One way to characterize the role of each receptor is to selectively inactivate one receptor population, thus pharmacologically ‘isolating’ the muscarinic receptor subtype of interest. Selective receptor inactivation can be achieved using either a selective, irreversible antagonist, or protection using a selective, reversible antagonist against a non-selective irreversible antagonist. Therefore, combination of these two approaches may provide optimal selective inactivation. Several muscarinic alkylating agents have been identified, including phenoxybenzamine, EEDQ (<em>N</em>-Ethoxycarbonyl-1-ethoxy-1,2-dihydroquinoline) and propylbenzilylcholine mustard. These irreversible antagonists do not, in general, discriminate between muscarinic receptor subtypes and are frequently used to estimate the affinity and relative efficacy of muscarinic agonists. Consequently, use of these irreversible antagonists provides estimations of the ‘receptor reserve’ associated with a response mediated by muscarinic receptor activation. In contrast, 4-DAMP mustard (4-diphenylacetoxy-<em>N</em>-(2-chloroethyl)piperidine) selectively inactivates M₃ receptors, but will not discriminate between M₁ M ₂ or M₄ receptors. In the absence of highly selective alkylating agents, receptor protection by reversible antagonists may be used. Thus, reversible antagonists, such as pirenzepine, methoctramine or <em>para</em>-fluorohexahydrosiladifenidol, at appropriate fractional receptor occupancies, may protect M₁ M₂ or M₃ receptors against alkylation by phenoxybenzamine. Selective alkylation of M₃ receptors by 4-DAMP mustard is enhanced with concurrent M₂ protection. This approach has been applied to defining the role of these muscarinic receptor subtypes in the control of ileal smooth muscle tone. These data suggest that, in ileum, M₂ receptors may act to inhibit β-adrenoceptor activation, thereby offsetting relaxation, while M₃ receptors directly mediate contraction.</p></div>","PeriodicalId":13733,"journal":{"name":"International Journal of Biochemistry","volume":"26 12","pages":"Pages 1357-1368"},"PeriodicalIF":0.0,"publicationDate":"1994-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-711X(94)90178-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18888614","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}