TECHNOLOGY FOCUS - BIOLOGY - Preferred Materials: (I) is a target molecule to be oxidized directly, e.g. a phenolic, aromatic compound with an alkoxy group or aromatic amine or a CotA-oxidizable mediator, especially a phenolic, non-phenolic aromatic or a compound containing the N-O group, e.g. 10-methylphenothiazine or 1-hydroxybenzotriazole. CotA may be replaced by a derivative, e.g. a mutant that retains at least 60% homology at the amino acid level.Preferred Process: Oxidation is in aqueous medium, optionally containing 0.1-75, preferably 5-25, % solvent, e.g. (m)ethanol, at pH 7-10.5, preferably 7.5-9.0. The concentration of (I) is 0.001-50, preferably 0.01-25,% and oxygen is supplied to, or generated in, the mixture to provide a partial pressure of 0.01-100, best 0.15-2, bars. Reaction is at 25-80, preferably 40-65,degreesC. Where a mediator is present, it is up to 10, preferably 0.01-1,%.    TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preparation: The cotA gene is derived from a Bacillus, especially a strain that produces pigmented endospores, specifically B. subtilis LK5 (DSM 13487) and is expressed by standard methods in bacteria or fungi, especially in the Escherichia coli K12 strain W3100 (ATCC 27325). EXAMPLE - Oxygen-delignified softwood cellulose (kappa value 17.4) was treated, as a 10% pulp, with 5 mg/g cellulose of N-hydroxyacetamide as mediator, then adjusted to pH 8 (sodium hydroxide), and homogenized. The mixture was treated with 0.5 ml/g cellulose of a CotA preparation, produced from Escherichia coli W3100 transformed with plasmid pCOT100 (containing the cotA gene of Bacillus subtilis LK5 under control of the lac promoter). The mixture was homogenized for 60 sec then incubated in an autoclave for 4 hr at 45degreesC under 3 bar oxygen. The treated cells were washed (i) with 10 volumes water at 50degreesC, with aqueous sodium hydroxide at 70degreesC (to eliminate lignin fragments) and as again. The degree of delignification was 21.4%; compare 7.9% for a control sample treated with a preparation from E. coli W3100 containing the plasmid pUC19.