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Characterisation of genes encoding two novel members of the aldo-keto reductase superfamily. 编码醛酮还原酶超家族两个新成员的基因特征。
Biochemistry international Pub Date : 1992-12-01
B P Dalrymple, J M Peters, T Vuocolo
{"title":"Characterisation of genes encoding two novel members of the aldo-keto reductase superfamily.","authors":"B P Dalrymple,&nbsp;J M Peters,&nbsp;T Vuocolo","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The predicted amino acid sequence of the protein encoded by a cDNA clone isolated from the protozoan haemoparasite Babesia bovis has approximately 22% amino acid identity with the Pichia stipitis xylose reductase. There are similar levels of amino acid identity with other members of the aldo-keto reductase superfamily. The identities include many residues highly conserved in the superfamily. However, the amino acid sequence of the B. bovis protein (AKR1) clearly lies outside the cluster of the previously characterized members of the superfamily. A putative protein encoded by a previously undescribed partially characterized open reading frame at the igrA (increased glyphosate resistance) locus of Pseudomonas sp. strain PG2982 also exhibits similarity to AKR1 and the aldo-keto reductases.</p>","PeriodicalId":8778,"journal":{"name":"Biochemistry international","volume":"28 4","pages":"651-7"},"PeriodicalIF":0.0,"publicationDate":"1992-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12653645","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: 0
Relationship between substrate activity and pKa value of phenols on sulfotransferase from Eubacterium A-44. 真杆菌A-44硫酸盐转移酶上酚类物质pKa值与底物活性的关系
Biochemistry international Pub Date : 1992-12-01
L Konishi-Imamura, D H Kim, K Kobashi
{"title":"Relationship between substrate activity and pKa value of phenols on sulfotransferase from Eubacterium A-44.","authors":"L Konishi-Imamura,&nbsp;D H Kim,&nbsp;K Kobashi","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The relationship between the kinetics of the enzyme activity and the structural features of phenolic donor and of acceptor substrates was investigated with a sulfotransferase from Eubacterium A-44, a human intestinal bacterium. The enzyme catalyzed the transfer of the sulfate group from the sulfate esters of phenol having a lower pKa to phenols having a higher pKa. When the Km values for acceptor substrates were measured at their optimal pH, a linear plot for log10Km versus the pKa with a slope of 0.615 was obtained. In addition, it is considered that the effect of pH on the Km values for the various acceptors is due to ionization of free enzyme. The kinetic behavior of bacterial sulfotransferase differed from that of mammalian phenol sulfotransferase.</p>","PeriodicalId":8778,"journal":{"name":"Biochemistry international","volume":"28 4","pages":"725-34"},"PeriodicalIF":0.0,"publicationDate":"1992-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12653652","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: 0
Downregulation of saturated fatty acid and upregulation of unsaturated fatty acid by 13-cis-retinoic acid in human prostate cancer cells. 13-顺式维甲酸对人前列腺癌细胞中饱和脂肪酸的下调和不饱和脂肪酸的上调。
Biochemistry international Pub Date : 1992-12-01
R Dahiya, H D Park, G Cassafer, J Cusick, P Narayan
{"title":"Downregulation of saturated fatty acid and upregulation of unsaturated fatty acid by 13-cis-retinoic acid in human prostate cancer cells.","authors":"R Dahiya,&nbsp;H D Park,&nbsp;G Cassafer,&nbsp;J Cusick,&nbsp;P Narayan","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Retinoids play a major role in regulation of epithelial cell growth and cellular differentiation, but their mechanism(s) of action are still unclear. In the present study, we examined the effects of 13-cis-retinoic acid (13-cis-RA) on cytotoxicity, growth properties, morphology, neutral lipids, phospholipids and fatty acids in cultured human prostate cancer cell lines. The results of these experiments suggest that 13-cis-RA (10 microM) inhibits the DNA synthesis and nude mice tumorigenicity by 2- to 3-fold, compared to control. Electron microscopy revealed more differentiated phenotypes after 13-cis-RA treatment. There was a significant increase in phosphatidylcholine and decrease in sphingomyelin in 13-cis-RA treated cells compared to control. The saturated fatty acids significantly decreased whereas unsaturated fatty acids were increased after 13-cis-RA treatment in prostate cancer cells. This study demonstrates for the first time that retinoic acid mediated downregulation of saturated fatty acids and upregulation of unsaturated fatty acid in human prostate cancer cells.</p>","PeriodicalId":8778,"journal":{"name":"Biochemistry international","volume":"28 6","pages":"981-7"},"PeriodicalIF":0.0,"publicationDate":"1992-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12464486","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: 0
DNA polymerase alpha, beta, and gamma activities in human lymphocytes stimulated by Tora-mame (Phaseolus vulgaris) lectin. tora - name (Phaseolus vulgaris)凝集素刺激人淋巴细胞DNA聚合酶α、β和γ活性。
Biochemistry international Pub Date : 1992-12-01
H Umekawa, K Kondoh, Y Furuichi, T Takahashi, S Yoshida
{"title":"DNA polymerase alpha, beta, and gamma activities in human lymphocytes stimulated by Tora-mame (Phaseolus vulgaris) lectin.","authors":"H Umekawa,&nbsp;K Kondoh,&nbsp;Y Furuichi,&nbsp;T Takahashi,&nbsp;S Yoshida","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>We measured the levels of the DNA polymerases alpha, beta, and gamma in human peripheral lymphocyte cells stimulated with Tora-mame lectin (TM-lectin) and the induction patterns were compared to those with other plant lectins, i.e., phytohemagglutinin (PHA) and pokeweed mitogen (PWM). The maximum activity of DNA polymerase alpha in lymphocytes was achieved at the concentration of 10 micrograms/ml with TM lectin and the dose response curve of TM lectin showed a sharp peak in contrast to that of PWM. During prolonged stimulation for 10 days, the time course of DNA polymerase alpha induction was different among these three lectins. A peak of alpha-enzyme was correlated with maximal incorporation of [3H]thymidine and was observed on the fourth day with TM lectin, on the third day with PHA, and sixth day with PWM. DNA polymerase beta in lymphocytes was also activated by the addition of these proteins. Two different peaks were observed during a 10-day period with every lectin, and TM lectin was most potent stimulator among them. The activity of DNA polymerase gamma in lymphocytes was at a very low but detectable level which increased slightly in response to TM lectin treatment. Although some variability of gamma-enzyme activity was observed after the seventh day, the pattern in the course of 7 days was similar among the lectins.</p>","PeriodicalId":8778,"journal":{"name":"Biochemistry international","volume":"28 6","pages":"1063-70"},"PeriodicalIF":0.0,"publicationDate":"1992-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12465425","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: 0
Effect of inorganic phosphate on hypoxanthine transport in isolated brain microvessels. 无机磷酸盐对离体脑微血管次黄嘌呤转运的影响。
Biochemistry international Pub Date : 1992-12-01
P Cardelli, A Fiori, M C Santulli, F Ceci, C Salerno, M R Savi, V Peresempio, R Strom
{"title":"Effect of inorganic phosphate on hypoxanthine transport in isolated brain microvessels.","authors":"P Cardelli,&nbsp;A Fiori,&nbsp;M C Santulli,&nbsp;F Ceci,&nbsp;C Salerno,&nbsp;M R Savi,&nbsp;V Peresempio,&nbsp;R Strom","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>In isolated brain microvessels, used as an in vitro model of the blood-brain barrier, the rate of hypoxanthine uptake was modulated by the presence of inorganic phosphate. A single high-capacity, low-affinity transport system was apparently active in a phosphate-free medium (Vmax = 840 pmol/mg protein/min, Km = 750/uM); in the presence of 10 mM phosphate, there was also a low-capacity, high-affinity system (Vmax = 47 pmol/mg protein/min, Km = 27/uM). The phosphate-dependent component was inactive in the absence of glucose or of Na+ ions, or upon addition of phloretine (but was scarcely affected by 2,4-dinitrophenol). This activity was apparently coupled to the intracellular phosphoribosyltransferase-catalyzed conversion of purines into the corresponding nucleotides: when inorganic phosphate was present in the suspending medium, labeled hypoxanthine was transported with higher efficiency and was readily converted to inosine monophosphate and to other related nucleotides. In the absence of phosphate ions, hypoxanthine was instead metabolized to xanthine and uric acid.</p>","PeriodicalId":8778,"journal":{"name":"Biochemistry international","volume":"28 5","pages":"823-34"},"PeriodicalIF":0.0,"publicationDate":"1992-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12536784","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: 0
Modulation of trichosanthin antigenicity by coupling to dextran. 葡聚糖偶联对天花粉蛋白抗原性的调节。
Biochemistry international Pub Date : 1992-12-01
W H Ko, C C Wong, H W Yeung, S C Tam
{"title":"Modulation of trichosanthin antigenicity by coupling to dextran.","authors":"W H Ko,&nbsp;C C Wong,&nbsp;H W Yeung,&nbsp;S C Tam","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Trichosanthin (TCS) is a plant-derived type I ribosome-inactivating protein with a wide spectrum of biological and pharmacological activities. Recently, it was covalently coupled to dextran in order to prolong its half-life in plasma. The major biological activities were generally retained but at lower potency. The immunogenicity of the dextran-trichosanthin (DX-TCS) was compared to that of TCS itself in this study. The results showed that mice immunized with TCS produced 8 times as much TCS-reactive IgE than those immunized with DX-TCS. However, both TCS and DX-TCS immunization produced similar titers of TCS-reactive IgG. A trace of dextran-reactive IgG was detected in mice immunized with DX-TCS. Thus, coupling of TCS to dextran reduced its antigenicity but slightly enhanced that of dextran, and the conjugate elicited less IgE than TCS.</p>","PeriodicalId":8778,"journal":{"name":"Biochemistry international","volume":"28 4","pages":"643-50"},"PeriodicalIF":0.0,"publicationDate":"1992-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12456911","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: 0
Monitoring of haemoglobin-methyl isocyanate adduct by high-performance liquid chromatography with diode array detector. 用二极管阵列检测器高效液相色谱法监测血红蛋白-异氰酸甲酯加合物。
Biochemistry international Pub Date : 1992-12-01
K S Venkateswaran, C D Raghuveeran, N Gopalan, G S Agarwal, M P Kaushik, R Vijayaraghavan
{"title":"Monitoring of haemoglobin-methyl isocyanate adduct by high-performance liquid chromatography with diode array detector.","authors":"K S Venkateswaran,&nbsp;C D Raghuveeran,&nbsp;N Gopalan,&nbsp;G S Agarwal,&nbsp;M P Kaushik,&nbsp;R Vijayaraghavan","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Carbamylation of haemoglobin by methyl isocyanate (MIC) was detected by high-performance liquid chromatography (HPLC) using a photodiode array detector following cyclisation of the N-terminal valine into methyl isopropyl hydantoin (MIH). MIH was also synthesised by reaction of MIC with valine, the chromatographic conditions standardised and the spectrum derived by a photodiode array detector recorded for confirmation of the identity of MIH. This HPLC method is specific, sensitive and suitable for the detection of exposure of blood samples to methyl isocyanate.</p>","PeriodicalId":8778,"journal":{"name":"Biochemistry international","volume":"28 4","pages":"745-50"},"PeriodicalIF":0.0,"publicationDate":"1992-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12652980","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: 0
Modulation of gastric mucosal calcium channel activity by sucralfate. 硫酸氢盐对胃粘膜钙通道活性的调节。
Biochemistry international Pub Date : 1992-12-01
B L Slomiany, J Liu, A Slomiany
{"title":"Modulation of gastric mucosal calcium channel activity by sucralfate.","authors":"B L Slomiany,&nbsp;J Liu,&nbsp;A Slomiany","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>A gastric mucosal calcium channel complex was isolated from solubilized epithelial cell membranes by affinity chromatography on wheat germ agglutinin. The complex following reconstitution into phosphatidylcholine vesicles exhibited an active 45Ca2+ uptake and responded to calcium channel activator, BAY K8644, and the antagonist, PN200-110. The uptake of 45Ca2+ was inhibited by an antiulcer agent, sucralfate, which at 100 micrograms/ml evoked maximal inhibitory effect of 52%. The channel complex on epidermal growth factor (EGF) binding in the presence of ATP showed an increase in tyrosine phosphorylation of 55 and 170kDa proteins, and the vesicles containing the phosphorylated channels displayed a 48% greater 45Ca2+ uptake. The phosphorylation process was inhibited by sucralfate, which also interfered with the binding of EGF to calcium channel protein. The results indicate that sucralfate has the ability to protect the cellular integrity from calcium imbalance.</p>","PeriodicalId":8778,"journal":{"name":"Biochemistry international","volume":"28 6","pages":"1125-34"},"PeriodicalIF":0.0,"publicationDate":"1992-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12458489","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: 0
Isolation and partial characterization of hyaluronan-protein-collagen complex (HA-PC) from fetal sheep skin of different gestational ages. 不同胎龄绵羊皮肤透明质酸蛋白胶原复合物(HA-PC)的分离及部分鉴定。
Biochemistry international Pub Date : 1992-12-01
N Bakshandeh, J W Siebert, R C Cabrera, Y Eidelman, M Longaker, R W Freund, H G Garg
{"title":"Isolation and partial characterization of hyaluronan-protein-collagen complex (HA-PC) from fetal sheep skin of different gestational ages.","authors":"N Bakshandeh,&nbsp;J W Siebert,&nbsp;R C Cabrera,&nbsp;Y Eidelman,&nbsp;M Longaker,&nbsp;R W Freund,&nbsp;H G Garg","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Hyaluronic acid (HA) has a positive effect on cell migration, differentiation and wound healing. Earlier work from our laboratory has shown the presence of biologically active proteins associated with HA. The protein associated with HA of fetal sheep skin varies in molecular weight depending on its gestational age. Specifically, the protein profile changes at 125 days of gestation, from a 60 KDa protein to a smaller protein of about 21 KDa. This time period coincides with the time that scarring becomes apparent in fetal sheep skin wounds. In this study, we have quantified changes in the proteins associated with HA with increasing gestational age, obtained amino acid profiles of these proteins with increasing gestational age, and proposed the existence of an HA-associated protein-collagen complex (HA-PC) which may serve as a scaffold for wound healing. Our results indicate that HA-PC content decreases from 42% of the dry weight at 75 days of gestation to 22% at 125 days of gestation. Protein content, in contrast, increases to 40% of the dry weight at 140 days of gestation. At the same time, collagen content increases from < 1% of the dry weight at 75 days to > 10% at 140 days. The increase in collagen content may account for the increase in total protein seen at 140 days. The expression of varying HA-PC's at different gestational ages may influence the kinetics of collagen fibrillogenesis and thus account for the previously noted late gestational change from \"scarless\" wound healing to \"adult-like\" wound healing in fetal sheep.</p>","PeriodicalId":8778,"journal":{"name":"Biochemistry international","volume":"28 5","pages":"843-51"},"PeriodicalIF":0.0,"publicationDate":"1992-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12463089","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: 0
Bull seminal plasma phosphodiesterase. Purification and general properties. 牛精浆磷酸二酯酶。净化和一般性质。
Biochemistry international Pub Date : 1992-12-01
M Codini, C Fini, P Paolotti, A Floridi
{"title":"Bull seminal plasma phosphodiesterase. Purification and general properties.","authors":"M Codini,&nbsp;C Fini,&nbsp;P Paolotti,&nbsp;A Floridi","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>A phosphodiesterase from bull seminal plasma was purified to homogeneity. The purification procedure involved sequential column chromatographies on DEAE-Sephadex A-50, ConA-Agarose, chromatofocusing and AMP-Agarose. The final yield was about 20% with a 3000-fold purification. As indicated by chromatofocusing, the enzyme is an acidic protein (pI approximately 4.6) and owing to its interaction with Concanavalin A it is also a glycoprotein. The SDS-PAGE showed that the purified phosphodiesterase seemed to be constituted of a single polypeptide chain of about 125 kDa. The enzyme did not show an absolute substrate specificity. Thus, it was able to hydrolyze 4-nitrophenyl ester of 5'-TMP (but not of 3'-TMP), cAMP, nucleic acids as well as NAD+, ADP and ATP. According to its enzymatic properties, bull seminal plasma phosphodiesterase is to be considered an oligonucleate 5'-nucleotidohydrolase. In addition the seminal plasma phosphodiesterase also showed phosphonate esterase activity.</p>","PeriodicalId":8778,"journal":{"name":"Biochemistry international","volume":"28 6","pages":"989-97"},"PeriodicalIF":0.0,"publicationDate":"1992-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12511404","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: 0
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