Catalysis of the reaction: a C28-steroid + O2 + reduced NADPH--hemoprotein reductase = a (22S)-22-hydroxy C28-steroid + H+ + H2O + oxidized NADPH--hemoprotein reductase. Also catalyzes the C-22 hydroxylation of a variety of C27 and C29 steroids.
steroid C-22 hydroxylase activity