6AMG

cyt P460 of Nitrosomonas sp. AL212

Summary for 6AMG

• Entry DOI: 10.2210/pdb6amg/pdb
• Descriptor: Cytochrome P460, HEME C (3 entities in total)
• Functional Keywords: metal binding protein
• Biological source: Nitrosomonas sp. AL212
• Total number of polymer chains: 2
• Total formula weight: 44644.21

Authors

Smith, M.,Lancaster, K. (deposition date: 2017-08-09, release date: 2017-12-20, Last modification date: 2024-11-06)

Primary citation

Smith, M.A.,Lancaster, K.M.
The Eponymous Cofactors in Cytochrome P460s from Ammonia-Oxidizing Bacteria Are Iron Porphyrinoids Whose Macrocycles Are Dibasic.
Biochemistry, 57:334-343, 2018

PubMed Abstract: The enzymes hydroxylamine oxidoreductase and cytochrome (cyt) P460 contain related unconventional "heme P460" cofactors. These cofactors are unusual in their inclusion of nonstandard cross-links between amino acid side chains and the heme macrocycle. Mutagenesis studies performed on the Nitrosomonas europaea cyt P460 that remove its lysine-heme cross-link show that the cross-link is key to defining the spectroscopic properties and kinetic competence of the enzyme. However, exactly how this cross-link confers these features remains unclear. Here we report the 1.45 Å crystal structure of cyt P460 from Nitrosomonas sp. AL212 and conclude that the cross-link does not lead to a change in hybridization of the heme carbon participating in the cross-link but rather enforces structural distortions to the macrocycle away from planarity. Time-dependent density functional theory coupled to experimental structural and spectroscopic analysis suggest that this geometric distortion is sufficient to define the spectroscopic properties of the heme P460 cofactor and provide clues toward establishing a relationship between heme P460 electronic structure and function.

PubMed: 29211462
DOI: 10.1021/acs.biochem.7b00921

Experimental method

X-RAY DIFFRACTION (1.45 Å)