PDBsum entry 6tae

Oxidoreductase

PDB id: 6tae

Contents

Protein chain

249 a.a.

Ligands

HEM

SO4

DOD ×154

PDB id:

6tae

Name:

Oxidoreductase

Title:

Neutron structure of ferric ascorbate peroxidase

Structure:

Ascorbate peroxidase. Chain: a. Synonym: cytosolic ascorbate peroxidase 1,uncharacterized protein. Engineered: yes

Source:

Glycine max. Soybean. Organism_taxid: 3847. Gene: apx1, glyma_u021900. Expressed in: escherichia coli. Expression_system_taxid: 562

Resolution:

1.90Å R-factor: 0.147 R-free: 0.189

Authors:

H.Kwon,J.Basran,J.M.Devos,T.E.Schrader,A.Ostermann,M.P.Blakeley, E.L.Raven,P.C.E.Moody

Key ref:

H.Kwon et al. (2020). Visualizing the protons in a metalloenzyme electron proton transfer pathway. Proc Natl Acad Sci U S A, 117, 6484-6490. PubMed id: 32152099 DOI: 10.1073/pnas.1918936117

Date:

29-Oct-19 Release date: 18-Mar-20

Protein chain

Q43758  (Q43758_SOYBN) -  L-ascorbate peroxidase from Glycine max

Seq: 250 a.a.

Struc: 249 a.a.

Enzyme reactions

• Enzyme class: E.C.1.11.1.11 - L-ascorbate peroxidase.
• Reaction: L-ascorbate + H2O2 = L-dehydroascorbate + 2 H2O
• Cofactor: Heme

Heme (Bound ligand (Het Group name = HEM) matches with 95.45% similarity)

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

reference

DOI no: 10.1073/pnas.1918936117

Proc Natl Acad Sci U S A 117:6484-6490 (2020)

PubMed id: 32152099

Visualizing the protons in a metalloenzyme electron proton transfer pathway.

H.Kwon, J.Basran, J.M.Devos, R.Suardíaz, M.W.van der Kamp, A.J.Mulholland, T.E.Schrader, A.Ostermann, M.P.Blakeley, P.C.E.Moody, E.L.Raven.

ABSTRACT

In redox metalloenzymes, the process of electron transfer often involves the concerted movement of a proton. These processes are referred to as proton-coupled electron transfer, and they underpin a wide variety of biological processes, including respiration, energy conversion, photosynthesis, and metalloenzyme catalysis. The mechanisms of proton delivery are incompletely understood, in part due to an absence of information on exact proton locations and hydrogen bonding structures in a bona fide metalloenzyme proton pathway. Here, we present a 2.1-Å neutron crystal structure of the complex formed between a redox metalloenzyme (ascorbate peroxidase) and its reducing substrate (ascorbate). In the neutron structure of the complex, the protonation states of the electron/proton donor (ascorbate) and all of the residues involved in the electron/proton transfer pathway are directly observed. This information sheds light on possible proton movements during heme-catalyzed oxygen activation, as well as on ascorbate oxidation.