... single and double bound intermediate states. The rate of the second step, the productive (specific) binding of hydroxylation- ... One clone inhibited the rat enzyme. Among the antibodies to the rat enzyme, seven clones showed the IgG1 subclass, four IgG2a ... The a domain of PDI could not be substituted by the PDI a domain, suggesting that both b and a domains contain regions ... in that production of a stable prolyl 4-hydroxylase requires collagen expression while assembly of a stable collagen requires ...