4.1.1.53 metabolism the enzyme is involved in biosynthesis and trunover of 2-phenylethylamine in maize 746609 4.1.1.53 metabolism the enzyme is involved in biosynthesis and turnover of 2-phenylethylamine in maize 746609 4.1.1.53 physiological function enzyme expression in Escherichia coli blocks motility and results in a 50fold decrease in the expression of class 2 and class 3 flagellar genes fliA and fliC, respectively. The expression of flhDC encoding the class 1 activator of the flagellarcascade is unchanged by the expression at both the transcriptional and translational levels. Phenethylamine, a decarboxylation product derived from phenylalanine, is able to mimic the overexpression and decrease both motility and class 2/3 flagellar gene expression. Both enzyme overexpression and phenethylamine strongly inhibit biofilm formation in Escherichia coli. Enzyme overexpression and exogenous phenethylamine can also reduce motility in other enteric bacteria, but have no effect on motility in non-enteric Gram-negative bacteria 728786