Some observations of the Δ1-dehydrogenation of steroids by Bacillus sphaericus

Abstract A study of the Δ 1 -dehydrogenation of steroids by intact cells and cell-free preparations of Bacillus sphaericus (ATCC 7055) has been made. The catalysis comprises of two phases, first a reversible reaction where a rapid exchange of the hydrogens of C-1α and C-2 of the steroid substrate occurs with the hydrogen of the medium, and the second, the essentially irreversible formation of the Δ 1 bond. Examination of these two phases with the use of tritium-labelled steroids and tritium oxide-enriched water has been made. Various electron acceptors have been tested with a cell-free preparation of Δ 1 -dehydrogenase and it has been shown that substances with the quinone structure are highly effective.