>4k1u_B mol:protein length:131 Steroid Delta-isomeraseMNLPTAQEVQGLMARFIELVDVGDIEAIVQMFADDATVEDPFGQPPIHGREQIAAFYRQGLGGGKVRACLTGPVRASHNGCGAMPFRVEMVWNGQPCALDVIDVMRFDEHGRIQTMQAYWSEVNLSVREPQ