A Model for the Electron Transfer Complex

FIGURE 7. Proposed large-scale structural reorganisation of ETF on binding to TMADH. Schematic representations of A, the ieT-inactivei complex, and B, the ieT-activei complex. The corresponding structures (Ca trace for protein) are shown in C and D, respectively. 

ENZYME OVER-REDUCTION AND SUBSTRATE INfflBITION MULTIPLE TURNOVER STUDIES 

TMADH exhibits an unusual dependence on trimethylamine concentration in steady-state reactions with either ETF or artificial electron acceptors. The enzyme is inhibited by high concentrations of substrate the reaction rate approaching a limiting and nonzero value (Falzon and 

FIGURE 8. Branching kinetic steady-state scheme proposed for TMADH, 

R222E), whereas flavinylation proceeds (albeit less efficiently) in a R222K mutant of TMADH where the positive charge is retained (Mewies et at., 

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