METABOLIC ENZYMES AND REGULATION OF FREE D-AMINO ACIDS IN INVERTEBRATES

无脊椎动物中的代谢酶和游离 D-氨基酸的调节

基本信息

批准号：
12460091
负责人：
ABE Hiroki
金额：
$ 10.43万
依托单位：
THE UNIVERSITY OF TOKYO
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2001
项目状态：
已结题

项目摘要

Alanine racemase was isolated from the muscle of black-tiger prawn. Partial amino acid sequences were obtained from the peptide fragments of purified enzyme. These sequences showed similarity with the enzyme from some bacteria but the similarities were below 40%. The prawn enzyme was considered to be rather different from bacterial counterpart in its structure and properties. Antibody was prepared on the basis of these partial sequences and used for the examination of subcellular distribution of the enzyme and the screening of cDNA library.Distribution of D-amino acid and D-aspartate oxidases in fish was species specific and considered to be related to food habits. The activity of D-amino acid oxidase increased in intestine, hepatopancreas, and kidney of carp with the administration of D-alanine, suggesting the enzyme is an inducible one. No enzyme induction occurred in D-aspartate oxidase with the administration of D-aspartate or D-glutamate. Both enzyme activities were subcellularly … More distributed in peroxisomes as is the case in mammals.cDNA cloning of D-amino acid oxidase from carp hepatopancreas gave a PCR product of 801 bp encoding 267 amino acid residues. The amino acid sequence showed similarities of 58-59% to human and porcine one.In the tissues of crayfish, kuruma prawn, and hard clam, D-, L-alanine increased significantly with increasing environmental salinity, indicating that D-alanine is a major osmolyte responsible for intracellular isosmotic regulation in these invertebrates. After hypersalinity acclimation, crayfish received severe anoxia increased D-, L-alanine in muscle and hepatopancreas which declined during recovery after anoxia. From these data, D-, L-alanine were considered to be anaerobic end-products together with lactate in crayfish.In the present study, physiological roles of D-alanine in invertebrates were clarified and the partial amino acid sequences of alanine racemase were determined for the first time. It was also clarified that fish species having no D-alanine metabolized D-amino acids to corresponding α-keto acid with D-amino acid and D-aspartate oxidases in liver and kidney and detoxified D-amino acids. Less

从黑天虎的肌肉中分离出丙氨酸种族酶。从纯化酶的胡椒片段获得了部分氨基酸序列。这些序列显示出与某些细菌的酶相似性，但相似性低于40％。原始酶被认为与细菌在其结构和特性中的不同。根据这些部分序列制备抗体，用于检查酶的亚细胞分布和cDNA库的筛选。鱼类中D-氨基酸和D-天冬氨酸的分布是特异的，并且被认为与食物习惯有关。 D-氨基酸氧化酶在肠道，肝癌和鲤鱼的肾脏中的活性增加了D-丙氨酸的给药，这表明该酶是一种诱导的酶。 D-天冬氨酸或D-天冬氨酸或D-谷氨酸的给药中，D-天冬氨酸氧化物中未发生酶诱导。两种酶活性都是亚细胞的……在哺乳动物中，在过氧化物体中分布更多。从鲤鱼肝癌中的cDNA克隆D-氨基酸氧化酶的CDNA克隆产生了编码267氨基酸残基的801 bp的PCR产物。氨基酸序列与人和猪的相似性相似。在小龙虾，库鲁马·皮林（Kuruma Pyrown）的组织中，kuruma pyrown和硬蛤clam，d-丙氨酸的硬质含量显着增加，随着环境盐度的增加，d-丙氨酸是这些甲壳虫的主要渗透量，这些甲壳氨酸是这些含有这些因素的主要渗透量。在过度适应过度之后，小龙虾在肌肉和肝癌中的D-，L-丙氨酸的严重缺氧增加了，在缺氧后恢复过程中下降。从这些数据中，D-，L-丙氨酸被认为是厌氧的终产物，以及小龙虾中的乳酸。在本研究中，首次确定了丙氨酸丙氨酸在无脊椎动物中的物理作用，并首次确定了丙氨酸种族酶的部分氨基酸序列。还澄清说，鱼类没有D-丙氨酸代谢的D-氨基酸，可将α-酮酸与D-氨基酸和D-氨基酸以及肝脏，肾脏和解毒的D-氨基酸中的D-天冬氨酸氧化物相对应。较少的