Pine 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.
A new series of 1H-pyrrolo[3,2-c]pyridine derivatives were designed and synthesised as colchicine-binding site inhibitors. Preliminary biological evaluations showed that most of the target compounds displayed moderate to excellent antitumor activities against three cancer cell lines (HeLa, SGC-7901, and MCF-7) in vitro. Among them, 10t exhibited the most potent activities against three cancer cell lines with IC50 values ranging from 0.12 to 0.21 μM. Tubulin polymerisation experiments indicated that 10t potently inhibited tubulin polymerisation at concentrations of 3 μM and 5 μM, and immunostaining assays revealed that 10t remarkably disrupted tubulin microtubule dynamics at a concentration of 0.12 μM. Furthermore, cell cycle studies and cell apoptosis analyses demonstrated that 10t at concentrations of 0.12 μM, 0.24 μM, and 0.36 μM significantly caused G2/M phase cell cycle arrest and apoptosis. The results of molecular modelling studies suggested that 10t interacts with tubulin by forming hydrogen bonds with colchicine sites Thrα179 and Asnβ349. In addition, the prediction of physicochemical properties disclosed that 10t conformed well to the Lipinski's rule of five.