The alcohol dehydrogenase with a broad range of substrate specificity regulates vitality and reproduction of the plant-parasitic nematodeBursaphelenchus xylophilus

Abstract

AbstractPine wilt disease, which is caused by the pine wood nematode (PWN),Bursaphelenchus xylophilus, has caused huge damage to pine forests around the world. In this study, we analysed the PWN transcriptome to investigate the expression of genes related to the associated bacterial speciesPseudomonas fluorescensand found that the geneadh-1 encoding alcohol dehydrogenase (ADH) was upregulated. The open reading frame ofadh-1, which encoded a protein of 352 amino acid residues, was cloned fromB. xylophilus. Recombinant ADH with a relative molecular weight of 39 kDa, was present mainly in inclusion bodies and was overexpressed inEscherichia coliBL21 (DE3) and purified after refolding. The biochemical assay revealed that recombinant ADH could catalyse the dehydrogen reaction of eight tested alcohols including ethanol in the presence of NAD+. Quantitative real-time RT-PCR analysis indicated that ethanol upregulatedadh-1 expression in PWN. Results of RNA interference and inhibition of ADH treatment indicated that downregulating expression ofadh-1 or inhibition of ADH could reduce ethanol tolerance and the vitality and reproduction ability ofB. xylophilus, suggesting thatadh-1 is involved in pathogenicity of PWN.