Bioinformatic analysis of glycoside hydrolases gene family in Plasmopara viticola

【Objective】Analyzed and predicted the glycoside hydrolases(GHs) gene family of Plasmopara viticola, and conducted bioinformatics analysis to provide theoretical basis for in-depth study of the molecular mechanism of GHs gene in pathogenicity of downy mildew.【Method】This study used SignalP 5.0 Server, Cluster W, MEGA6.0, MEME and other bioinformatics-related softwares to analyze the basic characteristics and the encoded proteins, genome distribution characteristics, conserved motifs, structural domains and subcellular location of the 60 GHs genes of the published whole genome of P. viticola.【Result】The protein sizes encoded by 60 GHs genes of P. viticola were between 128 and 774 aa, and most of them were concentrated between 200 and 500 aa. Among them, 53 proteins had signal peptides, and the molecular mass of the protein was between 14.90 and 85.45 kD. The theoretical isoelectric points(pI) was between 3.85 and 10.39. These genes were unevenly distributed in the genome. Twenty-seven of them had tandem repeats and clustering distribution, and the 3 GHs families(GH131, GH17 and GH6) with the largest number were concentrated in 7 scaffolds. Moreover, sequence alignment and phylogenetic tree analysis found that these tandem repeats and clusters of GHs genes were in the same phylogenetic tree branch. The motif enrichment analysis found 3 different motifs, and motif2 was conserved in GH6, GH17 and GH131 family genes of P. viticola. The domain analysis speculated that most GHs family genes were involved in the biological process of the cell wall. The subcellular localization prediction results showed that there were 53 GHs proteins located extracellular, 3 localized in the cytoplasm, and 4 localized on the mitochondria.【Conclusion】The results of bioinformatics analysis show that during the process of infecting the host, P. viticola may secrete a variety of GHs enzymes to destroy the structure of the cell wall and help it successfully colonize the host plant. This will clarify the function of the GHs family genes encoded by P. viticola and the molecular mechanism of pathogenicity.