This is the N-terminal domain found in putative tRNA-binding proteins found in archaea. Structural analysis from Pyrococcus horikoshii indicate that it is a helical domain where many conserved residues are found in the first three helices and are mainly located on the inverse side of the putative tRNA-binding site. A structural homology search suggested that this fold prefers to bind proteins/peptides [1].

1: Structure of protein PH0536 from Pyrococcus horikoshii at 1.7 A resolution reveals a novel assembly of an oligonucleotide/oligosaccharide-binding fold and an alpha-helical bundle. Gao YG, Yao M, Tanaka I; Proteins. 2008;71:503-508. PMID:18186487