The optimum pH for V-ATPase activity in D. pagei posterior gills
(pH 7.5) lies well within the range for the enzyme in posterior gill
microsomes from the diadromous crab Eriocheir sinensis (pH 7.0 to
8.0) (Onken and Putzenlechner, 1995) and from the diadromous
freshwater shrimp, Macrobrachium amazonicum (pH 7.5, Furriel,
unpublished data).