Function
Catalyzes the dehydratation of 7-alpha,12-alpha-dihydroxy-3-oxochol-4-enoate. The enzyme can also use 7-alpha-hydroxy-3-oxochol-4-enoate as a substrate but not 7-alpha,12-alpha-dihydroxy-3-oxochol-5-beta-anoate, 3-alpha,7-alpha,12-alpha-trihydroxychol-5-beta-anoate or 7-beta-hydroxy-3-oxochol-4-enoate.