Hydroxysteroid Dehydrogenase - Manual

Hydroxysteroid dehydrogenases catalyze the interconversion of hydroxyl and carboxyl groups of steroids. Those from Pseudomonas testosteroni are of two types:

1. 3α-Hydroxysteroid Dehydrogenase (1.1.1.50), (α enzyme):

2. 3β- and 17β-Hydroxysteroid Dehydrogenase:

The enzymes have useful application in the assay of steroids (Hurlock and Talalay 1958; Stempfel and Sidbury 1964; Moore 1972). They have been used for the determination of bile acids in blood (Iwata and Yamasaki 1964; Palmer 1969; Leslie 1969; Murphy et al. 1970; Schwarz et al. 1974).

It should be noted that Worthington supplies two preparations: one from the regular Pseudomonas testosteroni (ATCC 11966) culture which produces both the α and β enzymes, and a second from a mutant strain which produces almost only the α enzyme. By using both, the β-hydroxysteroid can be determined by difference.

Teller and Bongiavanni (1963) reported only slight activity of the mutant strain on epiandrosterone indicating but a trace of the β enzyme. Roe and Kaplan (1969) have investigated the specificities of the mutant and wild type strains, and this reference should be consulted for specific details.

Characteristics of Hydroxysteroid Dehydrogenase from Pseudomonas testosteroni:

3α hydroxysteroid dehydrogenase