Alkane degradation by Beauveria bassiana: gene expression analysis of cytochrome P450 monooxigenases

N. PEDRINI; M.P. JUÁREZ; N.O. KEYHANI

Warwick, Reino Unido

Congreso; 41st Annual Meeting of the Society for Invertebrate Pathology; 2008

Society for Invertebrate Pathology

The insect waxy layer, comprised of a complex mixture of lipids that include abundant amounts of straight-chain and methyl-branched, saturated and unsaturated hydrocarbons, represents the first barrier to infection by entomopathogenic fungi. Degradation of these hydrocarbons is presumed to occur via oxidation by cytochrome P450 enzyme systems. Seven gene fragments displaying high homology to cytochrome P450 alkane and/or aromatic oxidizing enzymes as well as a putative lipid-carrier protein were identified in a B. bassiana expressed sequence tagged (EST) collection. Full-length sequences for each gene were isolated by 5’ and 3’-rapid amplification of cDNA ends (RACE). Expression analysis of the genes by real-time RT PCR using fungal cells grown on n-hexadecane (C16), n-eicosane (C20), or n-octacosane (C28) revealed overlapping but differential expression of subsets of the isolated P450 genes. These data indicate that B. bassiana is likely to contain multiple hydrocarbon degradative pathways with overlapping substrate specificities.