Homodimeric and expanded behaviour of trimethylamine dehydrogenase in solution at different temperatures

摘要: Earlier studies using x-ray crystallography have shown that trimethylamine dehydrogenase (TMADH) from methylotropic bacteria exists as homodimers in the crystalline state. In this present hydrodynamic study we show is true also dilute solution conditions and investigate degree of swelling or relaxation protein solution. Analytical ultracentrifugation was used to determine molar mass whether homodimeric nature molecule crystal form — visualized by reproduced at temperatures between 4 40°C. The globular structure determined 40°C good agreement with crystallographic data although found be either more asymmetric highly hydrated —, a phenomenon increase temperature. structure, enzyme sediments homodimer (163,000±5,000) g/mol. concentration dependence sedimentation coefficient range 0–1 mg/ml, indicates no association dissociation occurs. These findings are additionally supported equilibrium 0 1.8 mg/ml. Finally, distribution various temperatures, it concluded conformationally flexible assumes an even expanded higher which calculations performed.