Cis-transIsomerase

The author found a new enzyme which is capable of isomerising maleic acid to fumaric acid. The enzyme was isolated from a bacterium belonging to Pseudomonas sp. and was concentrated to eight times against the original extract. The biochemical properties were determined as follows: the enzyme required glutathione or cysteine for full activity and was inhibited completely by monoiodoacetate and p-chloromercuribenzoate.