Screening of basidiomycetes for lignin peroxidase genes using a DNA probe

Basidiomycetes were screened for lignin peroxidase (LPO) genes using a DNA probe prepared from the LPO restriction fragment of Phanerochaete chrysosporium. Southern blot analysis showed restriction fragments of chromosomal DNA of Bjerkandera adusta and Coriolus consors hybridized with the probe. Bjerkandera adusta produced LPO in a glucose-peptone medium. Ion-exchange chromatography showed that this fungus produced multiple molecular forms of LPO. One of the enzymes, LPO-2, was purified and characterized. The molecular weight of LPO-2 was 41,000 with a pI of 4.2. Spectral analysis demonstrated that LPO-2 is a haem protein. The enzyme cleaved lignin model dimers mainly at the C alpha-C beta position of the side chain. The LPO-2 exhibited close similarity to LPOs of P. chrysosporium with respect to their basic properties.