Methylamine dehydrogenase of Pseudomonase sp. J Isolation and properties of the subunits.

Two kinds of subunits, light subunit (Mr =1300) and heavy subunit (Mr=40 000), were isolated from a methylamine dehydrogenase (Mr=105 000) of Pseudomonas sp. J. The isolation of the subunits was carried out by gel chromatography after the enzyme had been treated with 3M guanidine-HCl. Coexistence of both of the subunit exhibited an absorption maximum only at 278 nm but in addition to the peak at 278 nm. The results indicate that the prosthetic group, assumed to be a derivative of pyridoxal, was bound to the light subunit. The spectral changes of the light subunit were observed by addition of methylamine. Various physical and biochemical parameters of the subunits are reported.