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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 species Pseudomonas fluorescens and found that the gene adh- 1 encoding alcohol dehydrogenase (ADH) was upregulated. The open reading frame of adh -1, which encoded a protein of 352 amino acid residues, was cloned from B. xylophilus. Recombinant ADH with a relative molecular weight of 39 kDa, was present mainly in inclusion bodies and was overexpressed in Escherichia coli BL21 (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 upregulated adh -1 expression in PWN. Results of RNA interference and inhibition of ADH treatment indicated that downregulating expression of adh -1 or inhibition of ADH could reduce ethanol tolerance and the vitality and reproduction ability of B. xylophilus , suggesting that adh -1 is involved in pathogenicity of PWN. [ABSTRACT FROM AUTHOR]

Use of heavy atoms to calculate the phases in protein X-ray crystallography has now been extended to include site-specific in vivo incorporation of 3-iodo-tyrosine, enabled by the use of an archaeal aminoacyl-tRNA synthetase (Sakamoto et al., 2009).

The ubiquitin-like modifier NEDD8 promotes substrate ubiquitination via its covalent linkage to ubiquitin cullin-RING ligases. This depends on a NEDD8-specific sequential enzymatic cascade of E1, E2, and E3 enzymes. The identification of a second E2 enzyme for nedd8ylation recently reported in Molecular Cell (Huang et al., 2009) reveals novel insights into the molecular mechanism of target cullin selection.