ABSTRACT
This chapter examines the purification, characterization, and reaction mechanism of microbial amine oxidases (AO). An AO was inducibly formed in the mycelia of fungi when a monoamine or a diamine was the sole nitrogen source. A Gram-positive bacterium, Sarcina lutea, contains an amine oxidase specific for tyramine when it grows on bouillon medium. Polyamine oxidase (PAO) was found in mycelium of fungi belonging to the genera Aspergillus, Mucor, Penicillium, Rhizopus. PAO of A. terreus was purified and crystallized in the yield of 40%. PAO has a molecular weight of 130,000 and is composed of two identical subunits. Differential determination procedures for spermine and spermidine using beef plasma AO or fungal PAOs were based on combination of the rate assay method and the end point assay method. In the rate assay method, absorbance change obtained was very little and intensive care was required to estimate accurate enzyme activity.
