The slow conformational change is responsible for the apparent tight binding of NADH to the apoenzyme but is too slow to participate in the catalytic cycle when the enzyme is rapidly turning over.    From Wordnik.com.  [Journal of Biological Chemistry current issue] Reference

From many genera have been determined either as apoenzyme or as complex with its ligands (.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference