Partial purification and some properties of tryptophan decarboxylase from a Bacillus strain

Bacteria of different origin were screened for tryptophan decarboxylase activity. The best producer belonged to an unidentified taxonomic entity of the genus Bacillus. In complete medium it produced tryptamine from tryptophan. The decarboxylase could partially be purified from the cells by sonication and DEAE-cellulose chromatography. The enzyme had an Mr of 150 000 and a pH optimum of about 7, was stable up to 37 degrees C, and its Km was about 0.3 mM for tryptophan. The enzyme needed pyridoxal phosphate for maximum activity.