Abstract
Rat liver homogenate did not decompose L-threonine when incubated at pH 8, while it decomposed fairly well L-methionine. The decomposition rate of L-valine and L-lysine was intermediate of the former two. The same results were obtained when these amino acids were incubated with heart homogenate or kidney homogenate although the decomposition rate was lower than liver homogenate. Rat muscle homogenate and blood scarcely decomposed the above four amino acids.
When the liver homogenate was added with vitamin B6 group, only pyridoxal phosphate had remarkable effect on decomposing L-threonine to the high extent. The liver homogenate of the rat fed on excessive amount of pyridoxine had stronger L-threonine decomposing ability than the liver homogenate of the rat fed on ordinary diet or B6 deficient diet.
