8CNR

Hybrid Cluster Protein from the thermophilic methanogen Methanothermococcus thermolithotrophicus as isolated in a reduced state at 1.45-A resolution

Summary for 8CNR

• Entry DOI: 10.2210/pdb8cnr/pdb
• Descriptor: Hybrid cluster protein from the thermophilic methanogen Methanothermococcus thermolithotrophicus, (4R)-2-METHYLPENTANE-2,4-DIOL, MAGNESIUM ION, ... (11 entities in total)
• Functional Keywords: hybrid cluster, prismane protein, hybrid cluster protein, methanogenic archaea, anaerobic biochemistry, thermophile, metallocluster, nitric oxide reductase, hydroxylamine, oxidoreductase
• Biological source: Methanothermococcus thermolithotrophicus DSM 2095
• Total number of polymer chains: 1
• Total formula weight: 61847.90

Authors

Lemaire, O.N.,Wagner, T. (deposition date: 2023-02-24, release date: 2023-04-19, Last modification date: 2024-06-19)

Primary citation

Lemaire, O.N.,Belhamri, M.,Wagner, T.
Structural and biochemical elucidation of class I hybrid cluster protein natively extracted from a marine methanogenic archaeon.
Front Microbiol, 14:1179204-1179204, 2023

PubMed Abstract: Whilst widespread in the microbial world, the hybrid cluster protein (HCP) has been paradoxically a long-time riddle for microbiologists. During three decades, numerous studies on a few model organisms unravelled its structure and dissected its metal-containing catalyst, but the physiological function of the enzyme remained elusive. Recent studies on bacteria point towards a nitric oxide reductase activity involved in resistance during nitrate and nitrite reduction as well as host infection. In this study, we isolated and characterised a naturally highly produced HCP class I from a marine methanogenic archaeon grown on ammonia. The crystal structures of the enzyme in a reduced and partially oxidised state, obtained at a resolution of 1.45 and 1.36-Å, respectively, offered a precise picture of the archaeal enzyme intimacy. There are striking similarities with the well-studied enzymes from species regarding sequence, kinetic parameters, structure, catalyst conformations, and internal channelling systems. The close phylogenetic relationship between the enzymes from and many corroborates this similarity. Indeed, HCPs are closer to these bacterial homologues than to any other archaeal enzymes. The relatively high constitutive production of HCP in , in the absence of a notable nitric oxide source, questions the physiological function of the enzyme in these ancient anaerobes.

PubMed: 37250035
DOI: 10.3389/fmicb.2023.1179204

Experimental method

X-RAY DIFFRACTION (1.45 Å)