Aims: The white rot fungus Pycnoporus cinnabarinus MUCL 39533 is able to reduce vanillic acid to vanillin. Reduction of vanillic acid to vanillin catalysed by the key enzyme aryl-aldehyde dehydrogenase has been reported. Here we report the isolation and cloning of aryl-aldehyde dehydrogenase from P. cinnabarinus strain MUCL 39533. Methodology and results: An aryl-aldehyde dehydrogenase gene (PcALDH) was isolated from P. cinnabarinus by producing a partial cDNA sequence fragment of an aryl-aldehyde dehydrogenase gene through PCR. Degenerate PCR primers were designed based on codons corresponding to conserved amino acid regions of aryl-aldehyde dehydrogenases of several fungi and bacteria. The full-length PcALDH cDNA was obtained through ReverseTranscription-Polymerase Chain Reaction (RT-PCR) and Rapid Amplification cDNA Ends (RACE) PCR. PcALDH cDNA comprises an open reading frame of 1,506 bp that encodes a protein of 501 amino acids. The PcALDH predicted protein showed the highest amino acid sequence identity (84%) to ALDH from Trametes versicolor. In silico analysis of PcALDH indicated that it belongs to the ALDH super-family and Class 3 ALDH. Conclusion, significance and impact study: PcALDH cDNA was successfully isolated and characterized. Important motifs identified from the highly conserved PcALDH protein indicated that it belongs to the aldehyde dehydrogenase superfamily. The cDNA clone will be used in expression studies to confirm the catalytic function of the enzyme.
Vanillic Acid ; Flavoring Agents