Curation Notes: ureE (A0A0H2LU38, VPARA_50940) in Variovorax paradoxus (VARPD)

Summary

• Gene / Locus: ureE (VPARA_50940, UniProtKB A0A0H2LU38, reference proteome UP000035170, 200 aa).
• Domain Architecture & Sequence Features: HAMAP MF_00822, InterPro:IPR012406, N-terminal domain (Pfam:PF02814) and C-terminal domain (Pfam:PF05194), followed by a striking histidine-rich C-terminal tail (148-SHEHSHGGGHDHAHDHGNSKGPKPLVLAPELLDDHDHSHGHDHGHHGHSH-200, 15 His residues) homologous to the high-capacity $\text{Ni}^{2+}$-binding tail of Klebsiella aerogenes UreE (PMID:8318889(https://pubmed.ncbi.nlm.nih.gov/8318889/)).
• Mechanistic Role: Cytoplasmic nickel metallochaperone (GO:0016151 nickel cation binding, GO:0051604 protein maturation, GO:0043419 urea catabolic process) that supplies $\text{Ni}^{2+}$ to the UreD-UreF-UreG activation machinery in MODULE:urease_biogenesis_urea_hydrolysis (uree_nickel_supply / uree_nickel_metallochaperone).