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Ceriporiopsis sp. strain MD-1, isolated from forest soil, produced several extracellular enzymes that decolorized human hair melanin. Among them, three enzymes (E1, E2-1, and E2-2) were purified to homogeneity and characterized. The enzymes required hydrogen peroxide in their enzyme reactions and, typical of other fungal peroxidases, oxidized various phenol compounds such as guaiacol, but not 3,4-dimethoxybenzyl alcohol. The spectra of the three enzymes showed an absorption maximum at 406 nm, indicating that they were heme proteins. However, the A 406 / A 280 values of the enzymes were below 0.4, which was lower than those of other peroxidases. E2-1 and E2-2 were similar to each other in their molecular and catalytic properties, and they possibly represent products of posttranslational modifications and/or allelic variants of the same gene, mdcA . The corresponding cDNA was cloned and sequenced; the deduced amino acid sequence showed high identities to the manganese peroxidases from other microorganisms. The specific activities and K m values of E2-1 and E2-2 for synthetic and human hair melanins were much higher than those of Phanerochaete chrysosporium manganese peroxidase and lignin peroxidase.

A mutant Rhodococcus strain lacking the ability to utilize 1-chlorohexadecane was found to cis -desaturate aliphatic compounds, such as 1-chlorohexadecane, n -hexadecane, and heptadecanonitrile, yielding corresponding products with a double bond mainly at the ninth carbon from the terminal methyl groups. A new oxidative pathway involving the cis -desaturation step was suggested for alkane utilization by Rhodococcus spp.