E401A |
mutant displays a modest threefold increase in Km pyruvate, and a significant reduction in kcat/Km pyruvate |
Escherichia coli |
H407A |
mutation in E1, only modestly affects catalysis through the pyruvate decarboxylation step in isolated E1 (14% activity relative to parental E1), but inhibits the overall complex reaction by three orders of magnitude (0.15% activity compared to parental E1) |
Escherichia coli |
K403A |
mutant displays a modest threefold increase in Km pyruvate, and a significant reduction in kcat/Km pyruvate |
Escherichia coli |
additional information |
construction of a cysteine-less variant of the E1 component, onto which cysteines are substituted at selected loop positions. In the absence of ligand, the loop exists in two conformations, and the rate constant for loop movement is of the same order of magnitude as the turnover number for the enzyme under the same conditions |
Escherichia coli |
N404A |
mutation leads to the greatest reduction in overall activity among the alanine-substituted variants and also greatly affects the Kd methyl acetylphosphonate |
Escherichia coli |