Genomic Insights into Nematicidal Activity of a Bacterial Endophyte, Raoultella ornithinolytica MG against Pine Wilt Nematode

Plant Pathol J. 2018 Jun;34(3):250-255. doi: 10.5423/PPJ.OA.10.2017.0217. Epub 2018 Jun 1.

Abstract

Pine wilt disease, caused by the nematode Bursaphelenchus xylophilus, is one of the most devastating conifer diseases decimating several species of pine trees on a global scale. Here, we report the draft genome of Raoultella ornithinolytica MG, which is isolated from mountain-cultivated ginseng plant as an bacterial endophyte and shows nematicidal activity against B. xylophilus. Our analysis of R. ornithinolytica MG genome showed that it possesses many genes encoding potential nematicidal factors in addition to some secondary metabolite biosynthetic gene clusters that may contribute to the observed nematicidal activity of the strain. Furthermore, the genome was lacking key components of avermectin gene cluster, suggesting that nematicidal activity of the bacterium is not likely due to the famous anthelmintic agent of wide-spread use, avermectin. This genomic information of R. ornithinolytica will provide basis for identification and engineering of genes and their products toward control of pine wilt disease.

Keywords: bacterial endophyte; nematicidal activity; pine wilt disease (PWD).