BIOCHEMISTRY OF MEMBRANE AND CATALYTIC PROTEINS

膜和催化蛋白的生物化学

• 批准号: 3269829
• 负责人: BRUCE A MC FADDEN
• 金额: $ 23.07万
• 依托单位: WASHINGTON STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1976
• 资助国家: 美国
• 起止时间: 1976-06-01 至 1992-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3269829
• 关键词: Cyanophyta; Rhodospirillum; X ray crystallography; carbon dioxide fixation; cell membrane; chemical fingerprinting; chemical structure; chemical structure function; chloroplasts; chromatography; decarboxylases; density gradient ultracentrifugation; electron microscopy; enzyme mechanism; enzyme structure; immunologic assay /test; membrane proteins; microorganism metabolism; mutant; oxygenases; phosphoproteins; photosynthesis; photosynthetic bacteria; protein biosynthesis; protein sequence; spectrometry

Our specific aims are to elucidate fundamental correlates between structure and function for the enzyme ribulose bisphosphate carboxylase/oxygenase (RuBisCO) which catalyzes primary carbon dioxide fixation in nature and is one of the most abundant proteins on earth. This protein, which consists of large (L) and small (S) subunits in most species, undergoes activation to a catalytically active form which can then either catalyze carboxylative or oxygenolytic cleavage of ribulose bisphosphate. The latter initiates photorespiration, a process which opposes growth on carbon dioxide. Our long-range objective is to test the feasibility of enhancing photosynthesis and/or decreasing photorespiration by altering RuBisCO. The achievement of these objectives could increase crop yields and the global food supply. Our emphasis for many years has been on RuBisCO from bacteria. Bacteria not only provided enzymes that vary in quaternary structure (some lacking the S subunit) but one of the bacterial enzymes may be membrane-bound. A more basic understanding of enzyme structure and function and enzyme-membrane interactions may contribute to better treatment of a number of human diseases arising from enzyme or membrane malfunction. Specifically, we aim to investigate the structure and function of RuBisCO in terms of: (1) The function of S subunits including the interaction domain for L and S subunits and (2) the function of L subunits. These investigations will include chemical linking studies and in vitro mutagenesis of L and S subunit genes and will focus on one of the cyanobacteria, Anacystis nidulans. Parallel studies of the transformation of A. nidulans and cloroplasts by Co1E1 plasmids will be conducted to test the feasibility of incorporating interesting modifications of L and S subunit genes into cyanobacteria and, ultimately, into plants.

我们的具体目的是阐明结构之间的基本相关性 和核糖核糖双磷酸羧化酶/氧合酶的功能和功能 （rubisco）催化自然界中二氧化碳固定的（IS） 地球上最丰富的蛋白质之一。 该蛋白质包括 大多数物种中的大（L）和小（S）亚基的激活 催化活性形式，然后可以催化羧基 或核糖双磷酸盐的氧化裂解。 后者开始 光呼吸，这一过程反对二氧化碳生长。 我们的 远程目标是测试增强光合作用的可行性 和/或通过改变rubisco来减少光呼吸。 成就 这些目标可以提高农作物产量和全球粮食供应。 多年来，我们的重点一直是细菌的Rubisco。 细菌 不仅提供了在第四纪结构上有所不同的酶（有些缺乏 S亚基）但是其中一种细菌酶可能是膜结合的。 一个 对酶结构和功能的更基本的理解以及 酶 - 膜相互作用可能有助于更好地治疗一个数字 由酶或膜故障引起的人类疾病。 具体而言，我们旨在研究Rubisco的结构和功能 在：（1）S亚基的功能包括相互作用 L和S亚基的域以及（2）L亚基的功能。 这些 研究将包括化学联系研究和体外 L和S亚基基因的诱变，并将集中于其中一个 蓝细菌，anacystis nidulans。 转化的平行研究 将通过Co1e1质粒进行曲霉和碎屑。 结合L和S的有趣修改的可行性 亚基基因成蓝细菌，并最终成植物。