1B78

STRUCTURE-BASED IDENTIFICATION OF THE BIOCHEMICAL FUNCTION OF A HYPOTHETICAL PROTEIN FROM METHANOCOCCUS JANNASCHII:MJ0226

Summary for 1B78

• Entry DOI: 10.2210/pdb1b78/pdb
• Related: 2MJP
• Descriptor: PYROPHOSPHATASE (2 entities in total)
• Functional Keywords: structural genomics, pyrophosphatase, hyperthermal protein
• Biological source: Methanocaldococcus jannaschii
• Total number of polymer chains: 2
• Total formula weight: 44464.91

Authors

Hwang, K.Y.,Chung, J.H.,Han, Y.S.,Kim, S.H.,Cho, Y. (deposition date: 1999-01-27, release date: 2000-01-28, Last modification date: 2023-12-27)

Primary citation

Hwang, K.Y.,Chung, J.H.,Kim, S.H.,Han, Y.S.,Cho, Y.
Structure-based identification of a novel NTPase from Methanococcus jannaschii.
Nat.Struct.Biol., 6:691-696, 1999

PubMed Abstract: Almost half of the entire set of predicted genomic products from Methanococcus jannaschii are classified as functionally unknown hypothetical proteins. We present a structure-based identification of the biochemical function of a protein with an as yet unknown function from a M. jannaschii gene, Mj0226. The crystal structure of Mj0226 protein determined at 2.2 A resolution reveals that the protein is a homodimer and each monomer folds into an elongated alpha/beta structure of a new fold family. Comparisons of Mj0226 protein with protein structures in the database, however, indicate that one part of the protein is homologous to some of the nucleotide-binding proteins. Biochemical analysis shows that Mj0226 protein is a novel nucleotide triphosphatase that can efficiently hydrolyze nonstandard nucleotides such as XTP to XMP or ITP to IMP, but not the standard nucleotides, in the presence of Mg2+ or Mn2+ ions.

PubMed: 10404228
DOI: 10.1038/10745

Experimental method

X-RAY DIFFRACTION (2.2 Å)