The observed equilibrium constant (Kobs) for the reaction of choline acetyltransferase (EC 2.3.1.6) has been determined under physiological conditions. Using sigma and square brackets to indicate total concentrations of all ionic species present: (see article). The value of Kobs has been determined to be 12.3 plus or minus 0.6 at 38 degrees, pH 7.0 and ionic strength 0.25 M. The value at 25 deg...

We have identified five independent allelic mutations, defining the gene cha-1, that result in decreased choline acetyltransferase (ChAT) activity in Caenorhabditis elegans. Four of the mutant alleles, when homozygous, lead to ChAT reductions of greater than 98%, as well as recessive phenotypes of uncoordinated behavior, small size, slow growth and resistance to cholinesterase inhibitors. Anima...

In this study we examined the developmental roles of acetylcholine (ACh) by establishing and analyzing mice lacking choline acetyltransferase (ChAT), the biosynthetic enzyme for ACh. As predicted, ChAT-deficient embryos lack both spontaneous and nerve-evoked postsynaptic potentials in muscle and die at birth. In mutant embryos, abnormally increased nerve branching occurs on contact with muscle,...