European journal of biochemistry最新文献_第7页

High thermal and chemical stability of Thermus thermophilus seven-iron ferredoxin. Linear clusters form at high pH on polypeptide unfolding. 嗜热菌七铁氧还蛋白的高热稳定性和化学稳定性。在高pH下，多肽展开形成线状团簇。

European journal of biochemistry Pub Date : 2003-12-01 DOI: 10.1046/j.1432-1033.2003.03873.x

Susanne Griffin, Catherine L Higgins, Tewfik Soulimane, Pernilla Wittung-Stafshede

引用次数: 21

Characterization and cDNA cloning of a clofibrate-inducible microsomal epoxide hydrolase in Drosophila melanogaster. 黑腹果蝇氯贝特诱导微粒体环氧化物水解酶的鉴定和cDNA克隆。

European journal of biochemistry Pub Date : 2003-12-01 DOI: 10.1046/j.1432-1033.2003.03868.x

Kiyoko Taniai, Ahmet B Inceoglu, Kenji Yukuhiro, Bruce D Hammock

{"title":"Characterization and cDNA cloning of a clofibrate-inducible microsomal epoxide hydrolase in Drosophila melanogaster.","authors":"Kiyoko Taniai, Ahmet B Inceoglu, Kenji Yukuhiro, Bruce D Hammock","doi":"10.1046/j.1432-1033.2003.03868.x","DOIUrl":"https://doi.org/10.1046/j.1432-1033.2003.03868.x","url":null,"abstract":"In order to understand the roles of the epoxide hydrolases (EHs) in xenobiotic biotransformation in insects, we examined the induction of EHs by exogenous compounds in Drosophila melanogaster third instar larvae. Among the chemicals tested, clofibrate, a phenoxyacetate hypolipidermics drug, increased EH activity towards cis-stilbene oxide approximately twofold in larval whole-body homogenates. The same dose of clofibrate also induced glutathione S-transferase activity. The effect of clofibrate on EH induction was dose-dependent and the highest activity occurred with a 10% clofibrate application. Three other substrates conventionally used in EH assays (trans-stilbene oxide, trans-diphenylpropene oxide and juvenile hormone III) were poorly hydrolysed by larval homogenates, with or without clofibrate administration. Because the increased EH activity was localized predominantly in the microsomal fraction, we synthesized degenerate oligonucleotide primers with sequences corresponding to conserved regions of known microsome EHs from mammals and insects in order to isolate the gene. The 1597 bp putative cDNA of D. melanogaster microsomal EH (DmEH) obtained from a larval cDNA library encoded 463 amino acids in an open reading frame. Northern blot analysis showed that the transcription of DmEH was increased in larvae within 5 h of clofibrate treatment. Recombinant DmEH expressed in baculovirus hydrolysed cis-stilbene oxide (23 nmol.min-1.mg protein-1) and was located mainly in the microsomal fraction of virus-infected Sf9 cells. There was no detectable EH activity toward juvenile hormone III. These observations suggest that DmEH is involved in xenobiotic biotransformation, but not in juvenile hormone metabolism, in D. melanogaster.","PeriodicalId":11817,"journal":{"name":"European journal of biochemistry","volume":"270 23","pages":"4696-705"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/j.1432-1033.2003.03868.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24078781","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: 17

Fragments of pro-peptide activate mature penicillin amidase of Alcaligenes faecalis. 前肽片段激活粪孢菌成熟的青霉素酰胺酶。

European journal of biochemistry Pub Date : 2003-12-01 DOI: 10.1046/j.1432-1033.2003.03871.x

Volker Kasche, Boris Galunsky, Zoya Ignatova

{"title":"Fragments of pro-peptide activate mature penicillin amidase of Alcaligenes faecalis.","authors":"Volker Kasche, Boris Galunsky, Zoya Ignatova","doi":"10.1046/j.1432-1033.2003.03871.x","DOIUrl":"https://doi.org/10.1046/j.1432-1033.2003.03871.x","url":null,"abstract":"Penicillin amidase from Alcaligenes faecalis is a recently identified N-terminal nucleophile hydrolase, which possesses the highest specificity constant (kcat/Km) for the hydrolysis of benzylpenicillin compared with penicillin amidases from other sources. Similar to the Escherichia coli penicillin amidase, the A. faecalis penicillin amidase is maturated in vivo from an inactive precursor into the catalytically active enzyme, containing one tightly bound Ca2+ ion, via a complex post-translational autocatalytic processing with a multi-step excision of a small internal pro-peptide. The function of the pro-region is so far unknown. In vitro addition of chemically synthesized fragments of the pro-peptide to purified mature A. faecalis penicillin amidase increased its specific activity up to 2.3-fold. Mutations were used to block various steps in the proteolytic processing of the pro-peptide to obtain stable mutants with covalently attached fragments of the pro-region to their A-chains. These extensions of the A-chain raised the activity up to 2.3-fold and increased the specificity constants for benzylpenicillin hydrolysis mainly by an increase of the turnover number (kcat).","PeriodicalId":11817,"journal":{"name":"European journal of biochemistry","volume":"270 23","pages":"4721-8"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/j.1432-1033.2003.03871.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24078784","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: 15

Reactions of gold(III) complexes with serum albumin. 金(III)配合物与血清白蛋白的反应。

European journal of biochemistry Pub Date : 2003-12-01 DOI: 10.1046/j.1432-1033.2003.03862.x

Giordana Marcon, Luigi Messori, Pierluigi Orioli, Maria Agostina Cinellu, Giovanni Minghetti

{"title":"Reactions of gold(III) complexes with serum albumin.","authors":"Giordana Marcon, Luigi Messori, Pierluigi Orioli, Maria Agostina Cinellu, Giovanni Minghetti","doi":"10.1046/j.1432-1033.2003.03862.x","DOIUrl":"https://doi.org/10.1046/j.1432-1033.2003.03862.x","url":null,"abstract":"The reactions of a few representative gold(III) complexes -[Au(ethylenediamine)2]Cl3, [Au(diethylentriamine)Cl]Cl2, [Au(1,4,8,11-tetraazacyclotetradecane)](ClO4)2Cl, [Au(2,2',2'-terpyridine)Cl]Cl2, [Au(2,2'-bipyridine)(OH)2][PF6] and the organometallic compound [Au(6-(1,1-dimethylbenzyl)-2,2'-bipyridine-H)(OH)][PF6]- with BSA were investigated by the joint use of various spectroscopic methods and separation techniques. Weak metal-protein interactions were revealed for the [Au(ethylenediamine)2]3+ and [Au(1,4,8,11-tetraazacyclotetradecane)]3+ species, whereas progressive reduction of the gold(III) centre was observed in the cases of [Au(2,2'-bipyridine)(OH)2]+ and [Au(2,2',2'-terpyridine)Cl]2+. In contrast, tight metal-protein adducts are formed when BSA is reacted with either [Au(diethylentriamine)Cl]2+ and [Au(6-(1,1-dimethylbenzyl)-2,2'-bipyridine-H)(OH)]+. Notably, binding of the latter complex to serum albumin results in the appearance of characteristic CD bands in the visible spectrum. It is suggested that adduct formation for both of these gold(III) complexes occurs through coordination at the level of surface histidines. Stability of these gold(III) complexes/serum albumin adducts was tested under physiologically relevant conditions and found to be appreciable. Metal binding to the protein is tight; complete detachment of the metal from the protein has been achieved only after the addition of excess potassium cyanide. The implications of the present results for the pharmacological activity of these novel cytotoxic agents are discussed.","PeriodicalId":11817,"journal":{"name":"European journal of biochemistry","volume":"270 23","pages":"4655-61"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/j.1432-1033.2003.03862.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24080370","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: 82

Cholecystokinin rapidly stimulates CrkII function in vivo in rat pancreatic acini. Formation of CrkII-protein complexes. 胆囊收缩素在大鼠胰腺腺泡体内快速刺激CrkII功能。crkii蛋白复合物的形成。

European journal of biochemistry Pub Date : 2003-12-01 DOI: 10.1046/j.1432-1033.2003.03869.x

Alberto G Andreolotti, Maria J Bragado, Jose A Tapia, Robert T Jensen, Luis J Garcia-Marin

{"title":"Cholecystokinin rapidly stimulates CrkII function in vivo in rat pancreatic acini. Formation of CrkII-protein complexes.","authors":"Alberto G Andreolotti, Maria J Bragado, Jose A Tapia, Robert T Jensen, Luis J Garcia-Marin","doi":"10.1046/j.1432-1033.2003.03869.x","DOIUrl":"https://doi.org/10.1046/j.1432-1033.2003.03869.x","url":null,"abstract":"Crk belongs to a family of adapter proteins whose structure allows interaction with tyrosine-phosphorylated proteins and is therefore an important modulator of downstream signals, representing a convergence of the actions of numerous stimuli. Recently, it was demonstrated that cholecystokinin (CCK) induced tyrosine phosphorylation of proteins related to fiber stress formation in rat pancreatic acini. Here, we investigated whether CCK receptor activation signals through CrkII and forms complexes with tyrosine-phosphorylated proteins in rat pancreatic acini. We demonstrated that CCK promoted the transient formation of CrkII-paxillin and CrkII-p130Cas complexes with maximal effect at 1 min. Additionally, CCK decreased the electrophoretic mobility of CrkII. This decrease was time- and concentration-dependent and inversely related with its function. Carbachol and bombesin also decreased CrkII electrophoretic mobility, whereas epidermal growth factor, vasoactive intestinal peptide, secretin or pituitary adenylate cyclase-activating polypeptide had no effect. CCK-induced CrkII electrophoretic shift was dependent on the Src family of tyrosine kinases and occurred in the intact animal, suggesting a physiological role of CrkII mediating CCK actions in the exocrine pancreas in vivo.","PeriodicalId":11817,"journal":{"name":"European journal of biochemistry","volume":"270 23","pages":"4706-13"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/j.1432-1033.2003.03869.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24078782","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

Sensitivity to Hsp90-targeting drugs can arise with mutation to the Hsp90 chaperone, cochaperones and plasma membrane ATP binding cassette transporters of yeast. 酵母的Hsp90伴侣蛋白、辅伴侣蛋白和质膜ATP结合盒转运蛋白的突变可引起对Hsp90靶向药物的敏感性。

European journal of biochemistry Pub Date : 2003-12-01 DOI: 10.1046/j.1432-1033.2003.03866.x

Peter W Piper, Stefan H Millson, Mehdi Mollapour, Barry Panaretou, Giuliano Siligardi, Laurence H Pearl, Chrisostomos Prodromou

{"title":"Sensitivity to Hsp90-targeting drugs can arise with mutation to the Hsp90 chaperone, cochaperones and plasma membrane ATP binding cassette transporters of yeast.","authors":"Peter W Piper, Stefan H Millson, Mehdi Mollapour, Barry Panaretou, Giuliano Siligardi, Laurence H Pearl, Chrisostomos Prodromou","doi":"10.1046/j.1432-1033.2003.03866.x","DOIUrl":"https://doi.org/10.1046/j.1432-1033.2003.03866.x","url":null,"abstract":"The Hsp90 molecular chaperone catalyses the final activation step of many of the most important regulatory proteins of eukaryotic cells. The antibiotics geldanamycin and radicicol act as highly selective inhibitors of in vivo Hsp90 function through their ability to bind within the ADP/ATP binding pocket of the chaperone. Drugs based on these compounds are now being developed as anticancer agents, their administration having the potential to inactivate simultaneously several of the targets critical for counteracting multistep carcinogenesis. This investigation used yeast to show that cells can be rendered hypersensitive to Hsp90 inhibitors by mutation to Hsp90 itself (within the Hsp82 isoform of yeast Hsp90, the point mutations T101I and A587T); with certain cochaperone defects and through the loss of specific plasma membrane ATP binding cassette transporters (Pdr5p, and to a lesser extent, Snq2p). The T101I hsp82 and A587T hsp82 mutations do not cause higher drug affinity for purified Hsp90 but may render the in vivo chaperone cycle more sensitive to drug inhibition. It is shown that these mutations render at least one Hsp90-dependent process (deactivation of heat-induced heat shock factor activity) more sensitive to drug inhibition in vivo.","PeriodicalId":11817,"journal":{"name":"European journal of biochemistry","volume":"270 23","pages":"4689-95"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/j.1432-1033.2003.03866.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24078780","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: 62

A kinetic model of the branch-point between the methionine and threonine biosynthesis pathways in Arabidopsis thaliana. 拟南芥蛋氨酸和苏氨酸生物合成途径分支点的动力学模型。

European journal of biochemistry Pub Date : 2003-12-01 DOI: 10.1046/j.1432-1033.2003.03851.x

Gilles Curien, Stéphane Ravanel, Renaud Dumas

{"title":"A kinetic model of the branch-point between the methionine and threonine biosynthesis pathways in Arabidopsis thaliana.","authors":"Gilles Curien, Stéphane Ravanel, Renaud Dumas","doi":"10.1046/j.1432-1033.2003.03851.x","DOIUrl":"https://doi.org/10.1046/j.1432-1033.2003.03851.x","url":null,"abstract":"This work proposes a model of the metabolic branch-point between the methionine and threonine biosynthesis pathways in Arabidopsis thaliana which involves kinetic competition for phosphohomoserine between the allosteric enzyme threonine synthase and the two-substrate enzyme cystathionine gamma-synthase. Threonine synthase is activated by S-adenosylmethionine and inhibited by AMP. Cystathionine gamma-synthase condenses phosphohomoserine to cysteine via a ping-pong mechanism. Reactions are irreversible and inhibited by inorganic phosphate. The modelling procedure included an examination of the kinetic links, the determination of the operating conditions in chloroplasts and the establishment of a computer model using the enzyme rate equations. To test the model, the branch-point was reconstituted with purified enzymes. The computer model showed a partial agreement with the in vitro results. The model was subsequently improved and was then found consistent with flux partition in vitro and in vivo. Under near physiological conditions, S-adenosylmethionine, but not AMP, modulates the partition of a steady-state flux of phosphohomoserine. The computer model indicates a high sensitivity of cystathionine flux to enzyme and S-adenosylmethionine concentrations. Cystathionine flux is sensitive to modulation of threonine flux whereas the reverse is not true. The cystathionine gamma-synthase kinetic mechanism favours a low sensitivity of the fluxes to cysteine. Though sensitivity to inorganic phosphate is low, its concentration conditions the dynamics of the system. Threonine synthase and cystathionine gamma-synthase display similar kinetic efficiencies in the metabolic context considered and are first-order for the phosphohomoserine substrate. Under these conditions outflows are coordinated.","PeriodicalId":11817,"journal":{"name":"European journal of biochemistry","volume":"270 23","pages":"4615-27"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/j.1432-1033.2003.03851.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24080366","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: 69

The diacylglycerol and protein kinase C pathways are not involved in insulin signalling in primary rat hepatocytes. 二酰基甘油和蛋白激酶C通路不参与原代大鼠肝细胞的胰岛素信号传导。

European journal of biochemistry Pub Date : 2003-12-01 DOI: 10.1046/j.1432-1033.2003.03853.x

Irmelin Probst, Ulrich Beuers, Birgit Drabent, Kirsten Unthan-Fechner, Peter Bütikofer

{"title":"The diacylglycerol and protein kinase C pathways are not involved in insulin signalling in primary rat hepatocytes.","authors":"Irmelin Probst, Ulrich Beuers, Birgit Drabent, Kirsten Unthan-Fechner, Peter Bütikofer","doi":"10.1046/j.1432-1033.2003.03853.x","DOIUrl":"https://doi.org/10.1046/j.1432-1033.2003.03853.x","url":null,"abstract":"Diacylglycerol (DAG) and protein kinase C (PKC) isoforms have been implicated in insulin signalling in muscle and fat cells. We evaluated the involvement of DAG and PKC in the action of insulin in adult rat hepatocytes cultured with dexamethasone, but in the absence of serum, for 48 h. Our results show that although insulin stimulated glycolysis and glycogen synthesis, it had no effect on DAG mass or molecular species composition. Epidermal growth factor showed the expected insulin-mimetic effect on glycolysis, whereas ATP and exogenous phospholipase C acted as antagonists and abolished the insulin signal. Similarly to insulin, epidermal growth factor had no effect on DAG mass or molecular species composition. In contrast, both ATP and phospholipase C induced a prominent increase in several DAG molecular species, including 18:0/20:4, 18:0/20:5, 18:0/22:5 and a decrease in 18:1/18:1. These changes were paralleled by an increase in phospholipase D activity, which was absent in insulin-treated cells. By immunoblotting or by measuring PKC activity, we found that neither insulin nor ATP translocated the PKCalpha, -delta, -epsilon or -zeta isoforms from the cytosol to the membrane in cells cultured for six or 48 h. Similarly, insulin had no effect on immunoprecipitable PKCzeta. Suppression of the glycogenic insulin signal by phorbol 12-myristate 13-acetate, but not by ATP, could be completely alleviated by bisindolylmaleimide. Finally, insulin showed no effect on DAG mass or translocation of PKC isoforms in the perfused liver, although it reduced the glucagon-stimulated glucose output by 75%. Together these results indicate that phospholipases C and D or multiple PKC isoforms are not involved in the hepatic insulin signal chain.","PeriodicalId":11817,"journal":{"name":"European journal of biochemistry","volume":"270 23","pages":"4635-46"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/j.1432-1033.2003.03853.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24080368","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: 6

Kinetics of the quinone binding reaction at the QB site of reaction centers from the purple bacteria Rhodobacter sphaeroides reconstituted in liposomes. 脂质体中重组紫色球形红杆菌反应中心QB位点醌结合反应动力学。

European journal of biochemistry Pub Date : 2003-12-01 DOI: 10.1046/j.1432-1033.2003.03845.x

Francesco Milano, Angela Agostiano, Fabio Mavelli, Massimo Trotta

{"title":"Kinetics of the quinone binding reaction at the QB site of reaction centers from the purple bacteria Rhodobacter sphaeroides reconstituted in liposomes.","authors":"Francesco Milano, Angela Agostiano, Fabio Mavelli, Massimo Trotta","doi":"10.1046/j.1432-1033.2003.03845.x","DOIUrl":"https://doi.org/10.1046/j.1432-1033.2003.03845.x","url":null,"abstract":"Transmembrane proton translocation in the photosynthetic membranes of the purple bacterium Rhodobacter sphaeroides is driven by light and performed by two transmembrane complexes; the photosynthetic reaction center and the ubiquinol-cytochrome c oxidoreductase complex, coupled by two mobile electron carriers; the cytochrome and the quinone. This paper focuses on the kinetics and thermodynamics of the interaction between the lipophylic electron carrier ubiquinone-10 and the photosynthetic enzyme reconstituted in liposomes. The collected data were simulated with an existing recognized kinetic scheme and the kinetic constants of the uptake (7.2 x 107 M(-1) x s(-1)) and release (40 s(-1)) processes of the ligand were inferred. The results obtained for the quinone release kinetic constant are comparable to the rate of the charge recombination reaction from the state D(+)QA(-). Values for the kinetic constants are discussed as part of the overall photocycle, suggesting that its bottleneck may not be the quinone uptake reaction in agreement with a previous report.","PeriodicalId":11817,"journal":{"name":"European journal of biochemistry","volume":"270 23","pages":"4595-605"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/j.1432-1033.2003.03845.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24080364","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: 47

Cloning, characterization and expression analysis of interleukin-10 from the common carp, Cyprinus carpio L. 鲤鱼白细胞介素-10的克隆、鉴定及表达分析。

European journal of biochemistry Pub Date : 2003-12-01 DOI: 10.1046/j.1432-1033.2003.03854.x

Ram Savan, Daisuke Igawa, Masahiro Sakai

引用次数: 145