Occurrence and Some Properties of Two Threonine Dehydratases in Euglena gradis
نویسندگان
چکیده
Two threonine dehydratases, I and 11, were found to occur in Euglena gracilis and each enzyme was purified partially. Like the biosynthetic threonine dehydratases of other organisms, dehydratase I was feedback-inhibited by isoleucine and not affected by adenylates. Dehydratase I1 was not influenced by branched-chain amino acids and adenylates. Occurrence of dehydratase 11, with a much higher activity than dehydratase I, suggests that dehydration of threonine is not the key point in the regulation of isoleucine biosynthesis in E. gracih.
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