1TRB

CONVERGENT EVOLUTION OF SIMILAR FUNCTION IN TWO STRUCTURALLY DIVERGENT ENZYMES

1TRB の概要

• エントリーDOI: 10.2210/pdb1trb/pdb
• 分子名称: THIOREDOXIN REDUCTASE, FLAVIN-ADENINE DINUCLEOTIDE (3 entities in total)
• 機能のキーワード: oxidoreductase(flavoenzyme)
• 由来する生物種: Escherichia coli
• 細胞内の位置: Cytoplasm: P0A9P4
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 35299.25

構造登録者

Kuriyan, J.,Krishna, T.S.R. (登録日: 1991-09-07, 公開日: 1994-01-31, 最終更新日: 2024-02-14)

主引用文献

Kuriyan, J.,Krishna, T.S.,Wong, L.,Guenther, B.,Pahler, A.,Williams Jr., C.H.,Model, P.
Convergent evolution of similar function in two structurally divergent enzymes.
Nature, 352:172-174, 1991

PubMed Abstract: An example of two related enzymes that catalyse similar reactions but possess different active sites is provided by comparing the structure of Escherichia coli thioredoxin reductase with glutathione reductase. Both are dimeric enzymes that catalyse the reduction of disulphides by pyridine nucleotides through an enzyme disulphide and a flavin. Human glutathione reductase contains four structural domains within each molecule: the flavin-adenine dinucleotide (FAD)- and nicotinamide-adenine dinucleotide phosphate (NADPH)-binding domains, the 'central' domain and the C-terminal domain that provides the dimer interface and part of the active site. Although both enzymes share the same catalytic mechanism and similar tertiary structures, their active sites do not resemble each other. We have determined the crystal structure of E. coli thioredoxin reductase at 2 A resolution, and show that thioredoxin reductase lacks the domain that provides the dimer interface in glutathione reductase, and forms a completely different dimeric structure. The catalytically active disulphides are located in different domains on opposite sides of the flavin ring system. This suggests that these enzymes diverged from an ancestral nucleotide-binding protein and acquired their disulphide reductase activities independently.

PubMed: 2067578
DOI: 10.1038/352172a0

実験手法

X-RAY DIFFRACTION (2 Å)