| abstract |
The invention provides the preparation of an oxidase or oxidase-containing mixture by aerobic fermentation of a methylotrophic yeast, wherein a catalase-negative yeast is allowed to grow in a nutritive medium in the presence of a compound which induces expression of the oxidase gene but is not a substrate for the oxidase. n For example, methanol oxidase is formed by induction with formaldehyde or formiate. Examples of yeasts are Hansenula polymorpha and Pichia pastoris . Specific ratios of inducing agent and carbon source, e.g. glucose, are given. The yeasts are not capable of producing catalase, so that the oxidase produced can be used for producing hydrogen peroxide, e.g. when an alkanol is combined with methanol oxidase in a washing or bleaching process. The oxidase can also be used for qualitative and/or quantitative determination of a substrate for the oxidase, e.g. ethanol or amines, or be used as a catalyst for the oxidation of a substrate in chemical synthesis. |