This family represents a group of uncharacterised proteins including a bacterial stress protein YcjX. The crystal structure of YcjX from Shewanella oneidensis has now been solved, and shows it to be a Ras-like GTP-binding protein. However, YcjX utilizes a non-canonical switch 2' motif not found in any other G protein [1].

1: Crystal Structure of the YcjX Stress Protein Reveals a Ras-Like GTP-Binding Protein. Tsai JT, Sung N, Lee J, Chang C, Lee S, Tsai FTF; J Mol Biol. 2019;431:3179-3190. PMID:31202886