1EFV image
Deposition Date 1996-10-16
Release Date 1997-12-03
Last Version Date 2024-02-07
Entry Detail
PDB ID:
1EFV
Title:
THREE-DIMENSIONAL STRUCTURE OF HUMAN ELECTRON TRANSFER FLAVOPROTEIN TO 2.1 A RESOLUTION
Biological Source:
Source Organism:
Homo sapiens (Taxon ID: 9606)
Host Organism:
Method Details:
Experimental Method:
Resolution:
2.10 Å
R-Value Free:
0.22
R-Value Work:
0.17
R-Value Observed:
0.17
Space Group:
P 1 21 1
Macromolecular Entities
Polymer Type:polypeptide(L)
Molecule:ELECTRON TRANSFER FLAVOPROTEIN
Gene (Uniprot):ETFA
Chain IDs:A
Chain Length:315
Number of Molecules:1
Biological Source:Homo sapiens
Polymer Type:polypeptide(L)
Molecule:ELECTRON TRANSFER FLAVOPROTEIN
Gene (Uniprot):ETFB
Chain IDs:B
Chain Length:255
Number of Molecules:1
Biological Source:Homo sapiens
Primary Citation
Three-dimensional structure of human electron transfer flavoprotein to 2.1-A resolution.
Proc.Natl.Acad.Sci.USA 93 14355 14360 (1996)
PMID: 8962055 DOI: 10.1073/pnas.93.25.14355

Abstact

Mammalian electron transfer flavoproteins (ETF) are heterodimers containing a single equivalent of flavin adenine dinucleotide (FAD). They function as electron shuttles between primary flavoprotein dehydrogenases involved in mitochondrial fatty acid and amino acid catabolism and the membrane-bound electron transfer flavoprotein ubiquinone oxidoreductase. The structure of human ETF solved to 2.1-A resolution reveals that the ETF molecule is comprised of three distinct domains: two domains are contributed by the alpha subunit and the third domain is made up entirely by the beta subunit. The N-terminal portion of the alpha subunit and the majority of the beta subunit have identical polypeptide folds, in the absence of any sequence homology. FAD lies in a cleft between the two subunits, with most of the FAD molecule residing in the C-terminal portion of the alpha subunit. Alignment of all the known sequences for the ETF alpha subunits together with the putative FixB gene product shows that the residues directly involved in FAD binding are conserved. A hydrogen bond is formed between the N5 of the FAD isoalloxazine ring and the hydroxyl side chain of alpha T266, suggesting why the pathogenic mutation, alpha T266M, affects ETF activity in patients with glutaric acidemia type II. Hydrogen bonds between the 4'-hydroxyl of the ribityl chain of FAD and N1 of the isoalloxazine ring, and between alpha H286 and the C2-carbonyl oxygen of the isoalloxazine ring, may play a role in the stabilization of the anionic semiquinone. With the known structure of medium chain acyl-CoA dehydrogenase, we hypothesize a possible structure for docking the two proteins.

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Primary Citation of related structures