Canadian journal of biochemistry最新文献_第2页

[3H]Apomorphine binding to a GTP-sensitive dopaminergic site in bovine anterior pituitary gland. [3H]阿波啡与牛垂体前叶gtp敏感的多巴胺能位点的结合。

Canadian journal of biochemistry Pub Date : 1982-11-01 DOI: 10.1139/o82-134

T Di Paolo, B Gagné, P Poyet, F Labrie

{"title":"[3H]Apomorphine binding to a GTP-sensitive dopaminergic site in bovine anterior pituitary gland.","authors":"T Di Paolo, B Gagné, P Poyet, F Labrie","doi":"10.1139/o82-134","DOIUrl":"https://doi.org/10.1139/o82-134","url":null,"abstract":"The characteristics of binding of the potent dopaminergic agonist [3H]apomorphine have been studied in bovine anterior pituitary membranes. A high affinity binding site with an apparent dissociation constant (KD) of 0.7 nM and a number of binding sites of 56 fmol/mg protein has been measured when 10(-5) M dopamine was used to assess nonspecific binding. The order of potency of various agonists to compete with [3H]apomorphine binding is consistent with an interaction at a typical dopaminergic receptor: apomorphine greater than dopamine greater than (-)-epinephrine = (-)-norepinephrine much greater than (-)-isoproterenol. Competition for [3H]apomorphine binding by antagonists shows marked stereoselectivity, (+)-butaclamol being 4000 times more potent than (-)-butaclamol. Dihydroergocryptine, a potent dopaminergic agonist on prolactin release, as well as the dopaminergic antagonists spiroperidol, haloperidol, and (+)-butaclamol, compete for [3H]apomorphine binding at nanomolar concentrations. By contrast, adrenergic (phentolamine, propranolol, and clonidine) and serotonergic (serotonin, cyproheptadine, and methysergide) agonists and antagonists do not compete or are weak competitors at micromolar concentrations. Guanosine triphosphate (GTP) decreases [3H]apomorphine binding, the affinity of this ligand for the receptor being decreased 10 times by 300 microM GTP. The close correlation observed between the affinity of a series of agonists and antagonists for the [3H]apomorphine binding sites and their potency as modulators of prolactin release suggests that [3H]apomorphine binding sites are those involved in the control of prolactin secretion.","PeriodicalId":9508,"journal":{"name":"Canadian journal of biochemistry","volume":"60 11","pages":"1043-9"},"PeriodicalIF":0.0,"publicationDate":"1982-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1139/o82-134","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18187894","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: 2

Tryptic peptide analysis of the human apolipoprotein E isomorphs. 人载脂蛋白E异构体的色氨酸分析。

Canadian journal of biochemistry Pub Date : 1982-11-01 DOI: 10.1139/o82-133

L V Pereira, P J Dolphin

{"title":"Tryptic peptide analysis of the human apolipoprotein E isomorphs.","authors":"L V Pereira, P J Dolphin","doi":"10.1139/o82-133","DOIUrl":"https://doi.org/10.1139/o82-133","url":null,"abstract":"The nature of the polypeptide backbone of human apolipoprotein (apo) E present in the very low density lipoproteins (VLDL) of normal and homozygous type III hyperlipoproteinemic patients was investigated by tryptic cleavage fingerprinting and specific chemical modification studies. Apo E from normal subjects was resolved on polyacrylamide isoelectric focussing gels into five bands (apo E-I', E-I, E-II, E-III, and E-IV), whereas apo E from type III patients was resolved into three bands (apo E-I3', E-I3, and E-II3). The apo E isoforms, contained within unstained polyacrylamide gel slices, were washed to remove ampholytes, desialylated, and digested with L-1-tosylamido-2-phenylethylchloromethyl ketone treated trypsin. Autoradiography of 125I-labelled tryptic apo E peptides showed complete identity between all isoforms from normal subjects. High performance liquid chromatographic (HPLC) analysis showed that complete peptide identity exists between apo E-I', E-I, and E-II and between apo E-I3', E-I3, and E-II3. Distinct HPLC peptide profiles were found for apo E-II, E-III, E-IV, and E-II3. These resolved peak differences were reproducible between runs, between digests, and between apo E isolations, suggesting that the distinct profiles were neither a result of artifacts nor of contamination. Specific chemical modification studies revealed that human apo E isomorphism is due, in part, to differences in arginine and cysteine residues but not to lysine residues. These findings indicate that human apo E isomorphism results from differences in the primary amino acid sequence of the individual isoforms in addition to charged carbohydrate heterogeneity. Furthermore, the apo E isomorphic profile observed in homozygous type III hyperlipoproteinemic patients reflects both a deficiency of apo E-III and E-IV and the presence of the altered apo E-II isoprotein (apo E-II3).","PeriodicalId":9508,"journal":{"name":"Canadian journal of biochemistry","volume":"60 11","pages":"1032-42"},"PeriodicalIF":0.0,"publicationDate":"1982-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1139/o82-133","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18187893","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: 2

A rapid and quantitative high performance liquid chromatographic method for assaying bilirubin and its conjugates in bile. 一种快速定量测定胆汁中胆红素及其偶联物的高效液相色谱法。

Canadian journal of biochemistry Pub Date : 1982-11-01 DOI: 10.1139/o82-135

E R Gordon, C A Goresky

{"title":"A rapid and quantitative high performance liquid chromatographic method for assaying bilirubin and its conjugates in bile.","authors":"E R Gordon, C A Goresky","doi":"10.1139/o82-135","DOIUrl":"https://doi.org/10.1139/o82-135","url":null,"abstract":"A rapid and quantitative high performance liquid chromatographic method for assaying bilirubin and its conjugates in bile has been developed. It is based on the use of ion-pair reverse-phase chromatography, utilizing heptanesulfonic acid in an acetate buffer, with a progressively increasing gradient of acetonitrile. The method resolves the following bilirubin IX alpha conjugates from bile: bilirubin diglucuronide, the two isomeric forms of bilirubin monoglucoside monoglucuronide diester, the two isomeric forms of bilirubin monoglucuronide, and bilirubin diglucoside. Unconjugated bilirubin is then eluted from the column by increasing the flow rate. The method also resolves the bilirubin XIII alpha and III alpha isomers of both bilirubin and the conjugates. In each case, the bilirubin XIII alpha precedes and the bilirubin III alpha follows the bilirubin IX alpha component. The high performance chromatographic run is completed in 35 min. The identity of the conjugates was ascertained by use of reference compounds isolated by thin-layer chromatography and by recollection of chromatographic peaks with identification of their diazo derivatives. The method was shown to have sufficient sensitivity that in vitro conjugating systems can be explored. Recollection and reinjection indicated that no isomeric scrambling occurs during the analytical procedure.","PeriodicalId":9508,"journal":{"name":"Canadian journal of biochemistry","volume":"60 11","pages":"1050-7"},"PeriodicalIF":0.0,"publicationDate":"1982-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1139/o82-135","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18186834","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: 37

Purification of glucosylceramidase by affinity chromatography. 亲和层析法纯化糖基神经酰胺酶。

Canadian journal of biochemistry Pub Date : 1982-11-01 DOI: 10.1139/o82-132

P M Strasberg, J A Lowden, D Mahuran

{"title":"Purification of glucosylceramidase by affinity chromatography.","authors":"P M Strasberg, J A Lowden, D Mahuran","doi":"10.1139/o82-132","DOIUrl":"https://doi.org/10.1139/o82-132","url":null,"abstract":"Glucosylceramide: beta-glucosidase (glucocerebrosidase, EC 3.2.1.45) has been purified 12 900-fold from human placenta using a specific affinity column. The ligand, glucosyl sphingosine, prepared from glucocerebroside by alkaline hydrolysis, was attached to epoxy-activated Sepharose 6B. The enzyme was applied to the column in citrate--butanol or citrate--ethylene glycol solution at its pH optimum (5.6). No enzyme was bound in the presence of detergent. Glucocerebrosidase was eluted with citrate--taurocholate buffer at low pH or with citrate--taurocholate buffer containing D-gluconolactone at the pH optimum. Citrate--taurocholate solution alone at the pH optimum would not elute the enzyme. The enzyme hydrolyzed both the natural substrate, glucocerebroside, and the artificial substrate, 4-methylumbelliferyl glucopyranoside. Glucocerebrosidase migrated as a single band on 10% sodium dodecyl sulfate--polyacrylamide tube and (or) slab gels, corresponding to a molecular weight of 75 000. It also ran as a single zone of enzyme activity or protein on native gels, composed of 2.2% polyacrylamide--0.4% agarose containing sodium taurocholate. This is the first reported use of this gel system for the examination of glucocerebrosidase. Overall recovery is 30%. The procedure represents a more rapid and specific technique for purification of glucocerebrosidase than those previously reported.","PeriodicalId":9508,"journal":{"name":"Canadian journal of biochemistry","volume":"60 11","pages":"1025-31"},"PeriodicalIF":0.0,"publicationDate":"1982-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1139/o82-132","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18187890","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: 21

Modulation by phenobarbital of lipolytic activity in postheparin plasma and tissues of the rat. 苯巴比妥对大鼠肝素后血浆和组织中脂溶活性的调节。

Canadian journal of biochemistry Pub Date : 1982-11-01 DOI: 10.1139/o82-138

D M Goldberg, M W Roomi, A Yu

{"title":"Modulation by phenobarbital of lipolytic activity in postheparin plasma and tissues of the rat.","authors":"D M Goldberg, M W Roomi, A Yu","doi":"10.1139/o82-138","DOIUrl":"https://doi.org/10.1139/o82-138","url":null,"abstract":"Male rats injected with phenobarbital at a dose of 100 mg/kg for 5 days manifested increased postheparin lipolytic activity of fasting plasma. Inhibition studies with protamine sulphate, 1 M NaCl, and sodium dodecyl sulphate revealed that the activities of both lipoprotein lipase and hepatic triacylglycerol lipase were increased in the postheparin plasma of the drug-treated rats. Adipose tissue lipoprotein lipase activity was also increased in the phenobarbital-treated rats. The triacylglycerol lipase activity elutable by heparin from liver slices and the residual activity of liver microsomes increased significantly in the drug-treated rats. Lipoprotein lipase of cardiac muscle and red skeletal muscle was unaltered by phenobarbital treatment. The increased postheparin lipolytic activity of fasting phenobarbital-treated rats seems to be accountable through increased lipoprotein lipase activity of adipose tissue and increased triacylglycerol lipase activity of liver, both of which may contribute to the lowered fasting concentrations of serum triacylglycerol mediated by the drug, as previously reported.","PeriodicalId":9508,"journal":{"name":"Canadian journal of biochemistry","volume":"60 11","pages":"1077-83"},"PeriodicalIF":0.0,"publicationDate":"1982-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1139/o82-138","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18186835","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: 7

Characterization of the electrophoretic mobility mutation in the N protein of the tsD1 mutant of vesicular stomatitis virus New Jersey serotype. 水疱性口炎病毒新泽西血清型tsD1突变体N蛋白电泳迁移性突变的研究

Canadian journal of biochemistry Pub Date : 1982-11-01 DOI: 10.1139/o82-137

E Brown, L Prevec

{"title":"Characterization of the electrophoretic mobility mutation in the N protein of the tsD1 mutant of vesicular stomatitis virus New Jersey serotype.","authors":"E Brown, L Prevec","doi":"10.1139/o82-137","DOIUrl":"https://doi.org/10.1139/o82-137","url":null,"abstract":"Some isolates of the temperature sensitive mutant tsD1 of complementation group D of vesicular stomatitis virus of New Jersey serotype have a nucleocapsid (N) protein which shows an increased electrophoretic mobility on sodium dodecyl sulfate--polyacrylamide gel electrophoresis (SDS-PAGE) when compared with wild type. Utilizing techniques involving specific chemical cleavage at tryptophan or methionine residues, as well as enzymatic cleavage with carboxypeptidases A and B, we have determined that residues near the carboxyterminus are responsible for the electrophoretic difference of the mutant protein. We have further shown that there are no differences in the tryptic peptides of the mutant compared with the wild type or a non-ts revertant in this region of the protein. We have identified a tryptic peptide located outside the relevant carboxyterminal region which is distinct in mutant and revertant. We conclude that the mutation producing the aberrant electrophoretic mobility of N protein of the tsD1 mutant is a missense point mutation located at least 40 amino acid residues from the carboxyterminus and which interacts with a more proximal carboxyregion so as to influence electrophoretic mobility on SDS-PAGE.","PeriodicalId":9508,"journal":{"name":"Canadian journal of biochemistry","volume":"60 11","pages":"1065-76"},"PeriodicalIF":0.0,"publicationDate":"1982-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1139/o82-137","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17354987","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: 3

Effect of ACTH or zinc treatment on plasma aldosterone and corticosterone levels and on the in vitro steroid output from adrenocortical cells. ACTH或锌处理对血浆醛固酮和皮质酮水平以及肾上腺皮质细胞体外类固醇输出的影响。

Canadian journal of biochemistry Pub Date : 1982-11-01 DOI: 10.1139/o82-136

N Payet, J G Lehoux

{"title":"Effect of ACTH or zinc treatment on plasma aldosterone and corticosterone levels and on the in vitro steroid output from adrenocortical cells.","authors":"N Payet, J G Lehoux","doi":"10.1139/o82-136","DOIUrl":"https://doi.org/10.1139/o82-136","url":null,"abstract":"We have studied the effect of in vivo treatment with two forms of ACTH (Synacthen and Duracton) and of zinc hydroxide on plasma corticosteroid levels from adult Long Evans female rats. The corticosteroid output by isolated zona glomerulosa cells in vitro was also studied. Dose-response experiments showed that, after 2 days of treatment, Synacthen caused a 2.5- and 25.9-fold increase in plasma aldosterone and corticosterone levels, respectively, while maximal increases of 1.7- and 5.6-fold were obtained following treatment with Duracton. In contrast to elevated plasma steroid levels, the basal aldosterone and corticosterone output by isolated zona glomerulosa cells was significantly decreased for all doses of Synacthen administered. The 8 IU/day treatment with Synacthen produced an 86% diminution of aldosterone output while a treatment of 32 IU/day with Duracton gave only a 48.8% decrease. Concomitantly the Synacthen treatment provoked a high mitotic response in the zona glomerulosa cells (fivefold over control). A 2-week treatment with Synacthen resulted in elevated plasma aldosterone and corticosterone levels and produced a 92% diminution of aldosterone output by isolated zona glomerulosa cells. The aldosterone and corticosterone output from these cells was not enhanced by the addition of ACTH in the incubation media; zona glomerulosa cells of animals treated with Synacthen were no longer responsive to ACTH stimulation in vitro. The effect of a 2-day treatment with zinc hydroxide on plasma aldosterone and corticosterone levels and on steroid output by isolated adrenocortical cells was different from that of Synacthen. This meant that zinc was not the active principle of the Synacthen preparation. Our results indicate that long-term treatment with ACTH provokes profound functional changes at the adrenocortical zona glomerulosa level.","PeriodicalId":9508,"journal":{"name":"Canadian journal of biochemistry","volume":"60 11","pages":"1058-64"},"PeriodicalIF":0.0,"publicationDate":"1982-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1139/o82-136","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17355829","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

Convenient biosynthetic preparation of isomeric spin-labelled radioactive phosphatidic acids. 自旋标记放射性磷脂酸的便捷生物合成制备。

Canadian journal of biochemistry Pub Date : 1982-11-01 DOI: 10.1139/o82-130

L Stuhne-Sekalec, N Z Stanacev

引用次数: 5

Interaction of D-phenylalanine with Co(II)-substituted rabbit muscle pyruvate kinase: kinetic and optical properties. d -苯丙氨酸与Co(II)取代兔肌丙酮酸激酶的相互作用:动力学和光学性质。

Canadian journal of biochemistry Pub Date : 1982-09-01 DOI: 10.1139/o82-109

C Y Kwan, R C Davis

{"title":"Interaction of D-phenylalanine with Co(II)-substituted rabbit muscle pyruvate kinase: kinetic and optical properties.","authors":"C Y Kwan, R C Davis","doi":"10.1139/o82-109","DOIUrl":"https://doi.org/10.1139/o82-109","url":null,"abstract":"The kinetic and optical properties of Co(II)-substituted pyruvate kinase in the presence of D-phenylalanine (D-Phe) were investigated. The results are discussed in comparison with the effects of its optical isomer L-phenylalanine (L-Phe) on the same enzyme. The catalytic effect of D-Phe on rabbit muscle pyruvate kinase depended upon the nature of the activating divalent metal ion used. It has stimulatory effect on Mg(II)-activated enzyme, but inhibitory effect on Co(II)-activated enzyme. Unlike the inhibitory effect of L-Phe, the inhibition of Co(II)-enzyme by D-Phe was not sensitive to the changes of pH and temperature, could not be reversed by L-alanine (L-Ala), displayed hyperbolic kinetics, and was noncompetitive with respect to phosphoenopyruvate saturation. D-Phe induced substantial visible circular dichroism (CD) spectral changes of Co(II)-enzyme similar to those induced by L-Phe. Although ultraviolet CD spectrum was not affected, D-Phe induced an ultraviolet difference absorption spectral change very similar to, but much smaller than, that induced by L-Phe. Our results support that D-Phe and other amino acids interact with the enzyme at two different sites: a common site, causing similar conformational changes which bear little direct kinetic relevance, and a kinetically relevant site, which is sterically dependent upon the side chain of the amino acids.","PeriodicalId":9508,"journal":{"name":"Canadian journal of biochemistry","volume":"60 9","pages":"861-6"},"PeriodicalIF":0.0,"publicationDate":"1982-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1139/o82-109","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18186838","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: 1

Dissociation and characterization of pilin isolated from Pseudomonas aeruginosa strains PAK and PAO. 铜绿假单胞菌PAK和PAO分离匹林的分离及特性研究。

Canadian journal of biochemistry Pub Date : 1982-09-01 DOI: 10.1139/o82-110

T H Watts, C M Kay, W Paranchych

引用次数: 34