Kakuta Y, Igarashi T, Murakami T, Ito H, Matsui H, Honma M
Graduate School of Agriculture, Hokkaido University, Sapporo, Japan.
Biosci Biotechnol Biochem. 2001 Jul;65(7):1511-8. doi: 10.1271/bbb.65.1511.
A plant hormone, ethylene, is formed through 1-aminocyclopropane-1-carboxylic acid (ACC). A fungus, Penicillium citrinum, was found to synthesize ACC and to degrade ACC into 2-oxobutyrate and ammonia. ACC synthase, responsible for ACC synthesis in P. citrinum, was characterized on the molecular level by sequencing of N terminal and proteolytic peptides of the enzyme, and cloning and sequencing of its cDNA. The ACC synthase from P. citrinum had 430 amino acid residues and a shorter C terminal than the plant enzyme. The enzyme purified from Escherichia coli transformed with ACC-synthase-encoding DNA showed similar properties to those of the purified enzyme from P. citrinum. Saccharomyces cerevisiae with ACC synthase accumulated ACC in the medium with increasing time of incubation. The sequence of ACC synthase from P. citrinum was compared with that of the plant enzyme with discussion about important residues for catalysis.
一种植物激素乙烯是通过1-氨基环丙烷-1-羧酸（ACC）形成的。人们发现一种真菌，即桔青霉，能够合成ACC并将其降解为2-氧代丁酸和氨。负责桔青霉中ACC合成的ACC合酶，通过对该酶的N端和蛋白水解肽进行测序以及对其cDNA进行克隆和测序，在分子水平上得到了表征。桔青霉的ACC合酶有430个氨基酸残基，其C端比植物酶的C端短。用编码ACC合酶的DNA转化大肠杆菌后纯化得到的该酶，表现出与从桔青霉中纯化得到的酶相似的性质。含有ACC合酶的酿酒酵母在培养基中随着培养时间的增加会积累ACC。将桔青霉的ACC合酶序列与植物酶的序列进行了比较，并讨论了催化的重要残基。
