title: Cellobiose quinone oxidoreductase from the white rot fungus Phanerochaete chrysosporium is produced by intracellular proteolysis of cellobiose dehydrogenase.
abstract: The fungus Phanerochaete chrysosporium was grown in a 10-l automatic fermenter using cellobiose as carbon source to monitor the induction of cellobiose dehydrogenase (CDH) and cellobiose quinone oxidoreductase (CBQ) enzymes, and to search for tentative cbq and cdh genes and their transcriptional products. After 24 h of induction, CDH was detected in the culture supernatant and a protein was recognized by a specific anti-CDH polyclonal antibody in the sonicated biomass. Northern blot experiments performed with several fungal RNA samples showed, after 24 h of induction, only one single species of an mRNA transcript corresponding in size to the cdh gene (2.5 kb) The relative amount of this transcript decreased as a function of time. Southern blot experiments done with genomic DNA and database search in the recently available genome information also ruled out the presence in this strain of a separate cbq gene distinct from the cdh gene. Taken together, these results demonstrated that CBQ originates from the cdh gene. Furthermore, it is not produced by differential splicing but by a posttranslational, predominantly intracellular, proteolytic cleavage.
authors.affiliation: Division of Industrial Biotechnology, Center for Genetic Engineering and Biotechnology, P.O. Box 6162, Cubanacan, Havana, Cuba.
authors.forename: Manuel
authors.initials: M
authors.lastname: Raíces
authors.forename: Raquel
authors.initials: R
authors.lastname: Montesino
authors.forename: José
authors.initials: J
authors.lastname: Cremata
authors.forename: Bianca
authors.initials: B
authors.lastname: García
authors.forename: Walmer
authors.initials: W
authors.lastname: Perdomo
authors.forename: István
authors.initials: I
authors.lastname: Szabó
authors.forename: Gunnar
authors.initials: G
authors.lastname: Henriksson
authors.forename: B Martin
authors.initials: BM
authors.lastname: Hallberg
authors.forename: Göran
authors.initials: G
authors.lastname: Pettersson
authors.forename: Gunnar
authors.initials: G
authors.lastname: Johansson
mesh_terms: D000483:Alleles; D015139:Blotting, Southern; D015153:Blotting, Western; D002237:Carbohydrate Dehydrogenases / Q000096:biosynthesis* / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D005656:Fungal Proteins / Q000096:biosynthesis* / Q000737:chemistry; D020075:Phanerochaete / Q000235:genetics / Q000378:metabolism*; D012697:Serine Endopeptidases; D014158:Transcription, Genetic
chemical_list: D005656:Fungal Proteins; D002237:Carbohydrate Dehydrogenases; C019859:cellobiose-quinone oxidoreductase; D012697:Serine Endopeptidases; C036813:lysyl endopeptidase