title: Archaeal ubiquitin-like proteins: functional versatility and putative ancestral involvement in tRNA modification revealed by comparative genomic analysis.
authors.affiliation: National Center for Biotechnology Information, NLM, National Institutes of Health, Bethesda, MD 20894, USA.
authors.forename: Kira S
authors.initials: KS
authors.lastname: Makarova
authors.forename: Eugene V
authors.initials: EV
authors.lastname: Koonin