Isoforms of L-lysine α-oxidase from Trichoderma sp.

Several purification methods were tested and the optimal procedure for obtaining L-lysine α-oxidase from fungi Trichoderma sp. and its isoform (minor L-lysine α-oxidase) was worked out. The enzyme and its isoform were obtained in a homogeneous state, the most important physicochemical properties were studied, and a number of differences between them were found. The most marked differences between L-lysine α-oxidase and its isoform were observed in the molecular weight (120 and 100 kD, respectively), in the isoelectric point (pI 4.4 and 5.6, respectively), and in the specific activity (90-95 and 17-20 U/mg) in experiments where L-lysine where used as substrate. ©1996 Plenum Publishing Corporation.