First insights into the genome of ‘Candidatus Phytoplasma rubi’ highlight effector protein repertoire of 16SrV phytoplasmas

The elm yellows phytoplasma group include phytopathogenic strains associated with important insect vector-borne diseases in grapevine, alder, elm, Chinese jujube and Rubus spp. such as raspberry and blackberry. The Rubus stunt disease is associated with the presence of ‘Candidatus Phytoplasma rubi’. In contrast to other 16SrV phytoplasma taxa “flavescence dorée” and ‘Ca. P. ziziphi’, no genome sequence of this phytoplasma is available. The complete genome of ‘Ca. P. rubi’ strain RS enabled a comprehensive analysis of the derived protein content. First analyses revealed a group-specific 16SrV metabolism as well as a diversified secretome that includes two conserved effector proteins.