Ligninases fromChrysonilia sitophila (TFB-27441 strain)

Ligninase found in the extracellular medium of cultures ofChrysonilia sitophila was purifieded by ion exchange chromatography. Sodium dodecylsulfate/polyacrylamide gel electrophoresis allowed the determination of 68,000, 48,300, and 48,000 daltons for the molecular weights of ligninase I, II, and III, respectively. The absorption spectrum of the enzymes indicated the presence of a heme prosthetic group. The absorption maximum of the native enzyme II at 400 nm decreased in the presence of one equivalent of hydrogen peroxide. With an additional equivalent of phenol the maximum at 400 nm shifted to 417 nm. This spectrum is similar to horseradish peroxidase compound II. The pyridine hemochromogen absorption spectrum and iron content indicated that ligninases I, II, and III contained a Fe/heme ratio values of 0.8, 1.3, and 1.2 by a molecule of protein, respectively. These enzymes oxidize lignin efficiently, followed by the fluorescence technique and by the photon emission method.