17alpha-hydroxypregnenolone + oxidized [NADPH--hemoprotein reductase] + H2O + H(+) => pregnenolone + reduced [NADPH--hemoprotein reductase] + O2
17alpha-hydroxypregnenolone + oxidized [nadph--hemoprotein reductase] + h2o + h(+) => pregnenolone + reduced [nadph--hemoprotein reductase] + o2
17alpha-hydroxypregnenolone + oxidized [NADPH--hemoprotein reductase] + H2O + H(+) => pregnenolone + reduced [NADPH--hemoprotein reductase] + O2
17alpha-hydroxypregnenolone + oxidized [nadph--hemoprotein reductase] + h2o + h(+) => pregnenolone + reduced [nadph--hemoprotein reductase] + o2