Interdomain motion in liver alcohol dehydrogenase. Structural and energetic analysis of the hinge bending mode.

摘要: A study of the hinge bending mode in enzyme liver alcohol dehydrogenase is made by use empirical energy functions. The a dimer, with each monomer composed coenzyme binding domain and catalytic large cleft between two. Superposition apoenzyme holoenzyme crystal structures used to determine rigid rotation axis for closing cleft. It shown that body transformation structure corresponds 10 degrees about this axis. not along least-motion path but instead coming closer sliding motion. Estimation associated interdomain motion over range 90 (-40 50 degrees, where 0 minimized structure) demonstrates local structural relaxation makes possible large-scale rotations relatively small increments. variety rearrangements are characterized. They involve region residues provide covalent connections two domains certain loop regions brought into contact rotation. Differences point existence alternative conformations loops importance ligands rearrangements.