2VOW

An oxidized tryptophan facilitates copper-binding in Methylococcus capsulatus secreted protein MopE. The structure of recombinant MopE to 1.65AA

Summary for 2VOW

• Entry DOI: 10.2210/pdb2vow/pdb
• Related: 2VOV 2VOX
• Descriptor: SURFACE-ASSOCIATED PROTEIN, GLYCEROL, CALCIUM ION, ... (4 entities in total)
• Functional Keywords: metal-binding protein, oxidized tryptophan, methanotroph bacterium, kunurenine, copper homeostasis, metal binding protein
• Biological source: METHYLOCOCCUS CAPSULATUS
• Total number of polymer chains: 1
• Total formula weight: 36314.02

Authors

Helland, R.,Fjellbirkeland, A.,Karlsen, O.A.,Ve, T.,Lillehaug, J.R.,Jensen, H.B. (deposition date: 2008-02-22, release date: 2008-03-18, Last modification date: 2023-12-13)

Primary citation

Helland, R.,Fjellbirkeland, A.,Karlsen, O.A.,Ve, T.,Lillehaug, J.R.,Jensen, H.B.
An Oxidized Tryptophan Facilitates Copper Binding in Methylococcus Capsulatus-Secreted Protein Mope.
J.Biol.Chem., 283:13897-, 2008

PubMed Abstract: Proteins can coordinate metal ions with endogenous nitrogen and oxygen ligands through backbone amino and carbonyl groups, but the amino acid side chains coordinating metals do not include tryptophan. Here we show for the first time the involvement of the tryptophan metabolite kynurenine in a protein metal-binding site. The crystal structure to 1.35 angstroms of MopE* from the methane-oxidizing Methylococcus capsulatus (Bath) provided detailed information about its structure and mononuclear copper-binding site. MopE* contains a novel protein fold of which only one-third of the structure displays similarities to other known folds. The geometry around the copper ion is distorted tetrahedral with one oxygen ligand from a water molecule, two histidine imidazoles (His-132 and His-203), and at the fourth distorted tetrahedral position, the N1 atom of the kynurenine, an oxidation product of Trp-130. Trp-130 was not oxidized to kynurenine in MopE* heterologously expressed in Escherichia coli, nor did this protein bind copper. Our findings indicate that the modification of tryptophan to kynurenine and its involvement in copper binding is an innate property of M. capsulatus MopE*.

PubMed: 18348978
DOI: 10.1074/JBC.M800340200

Experimental method

X-RAY DIFFRACTION (1.65 Å)