Symbiopectobacterium sp. Martinson et al. 2020 Martinson V.G. Gawryluk R.M.R. Gowen B.E. Curtis C.I. Jaenike J. Perlman S.J. Multiple origins of obligate nematode and insect symbionts by a clade of bacteria closely related to plant pathogens. 2020 117 50 31979 31986 Proceedings of the National Academy of Sciences of the United States of America Proc Natl Acad Sci U S A 0027-8424 1091-6490 10.1073/pnas.2000860117 33257562 Howardula aoronymphium clone 2026.