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Studies on the enzymic degradation of L-serine O-sulphate by a rat liver preparation.

ABSTRACT: 1. The enzyme system of rat liver responsible for the degradation of l-serine O-sulphate was purified 300-fold and the optimum conditions for the activity were determined. 2. Inorganic sulphate, pyruvate and ammonia were found to be the products of enzyme action on lserine O-sulphate, being formed in equivalent amounts under all conditions examined. No free l-serine was detected as a product of enzyme action. 3. The enzyme preparation was free from other serine-metabolizing systems such as O-phospho-l-serine phosphatase and l-serine dehydratase. 4. The enzyme has a very narrow substrate specificity and is inactive towards a wide variety of related sulphate esters and amino acids. 5. Pyridoxal 5'-phosphate is capable of catalysing the non-enzymic breakdown of l-serine O-sulphate in the presence of metal salts to yield inorganic sulphate, pyruvate and ammonia as products. 6. The possible role of pyridoxal 5'-phosphate as a coenzyme in the enzymic degradation of l-serine O-sulphate is discussed.

SUBMITTER: Thomas JH

PROVIDER: S-EPMC1198333 | biostudies-other | 1967 Nov

REPOSITORIES: biostudies-other

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The enzymic degradation of L-serine O-sulphate by a specific system from pig liver. Studies on the mechanism of the reaction.

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The enzymic degradation of L-serine O-sulphate. Mechanism of the reaction.

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