Preliminary X-ray diffraction studies of rabbit muscle triose phosphate isomerase (TIM)

Triose phosphate isomerase (TIM) is responsible for the interconversion bet ween GAP and DHAP in the glycolytic pathway. Two crystal forms belonging to space group P2(1)2(1)2(1) were obtained by the hanging-drop method and wer e designated A and B. Synchrotron X-ray diffraction data were collected for both forms. Form A had unit-cell parameters a = 65.14, b = 72.45, c = 93.2 4 Angstrom and diffracted to 2.25 Angstrom at 85 K, whereas form B had unit -cell parameters a = 73.02, b = 79.80, c = 172.85 Angstrom and diffracted t o 2.85 Angstrom at room temperature. Molecular replacement was employed to solve the structures, using human TIM as a search model. Further refinement of both structures is under way and is expected to shed light on the recen tly reported conformational studies for rabbit TIM.