Reaction catalyzed by chlorophyllide a 31-hydratase (4.2.1.165), 3-vinyl bacteriochlorophyllide d 31-hydratase (4.2.1.169)
+
H2O
=
3-vinyl bacteriochlorophyllide a
+
H2O
=
(31RS)-3-(1-hydroxyethyl) bacteriochlorophyllide a