alpha-D-ribose 1,5-bisphosphate <=> D-ribulose 1,5-bisphosphate
alpha-d-ribose 1,5-bisphosphate <=> d-ribulose 1,5-bisphosphate
alpha-D-ribose 1,5-bisphosphate <=> D-ribulose 1,5-bisphosphate
alpha-d-ribose 1,5-bisphosphate <=> d-ribulose 1,5-bisphosphate