Glutathione peroxidase

Glutathione peroxidase 1
	Belt and surface model according to PDB 2F8A
	Existing structural data : 2f8a
Properties of human protein
Mass / length primary structure	201 AS ; 21.9 kDa
Secondary to quaternary structure	Homotetramer
Identifier
Gene names	GPX1 ; GSHPX-1
External IDs	OMIM : 138320 ; UniProt : P07203 ; CAS number : 9013-66-5;
Enzyme classification
EC, category	1.11.1.9 , oxidoreductase
Response type	Redox reaction
Substrate	2 glutathione + H 2 O 2
Products	Glutathione disulfide + 2 H 2 O
Occurrence
Homology family	Thioredoxin
Parent taxon	Creature

The glutathione peroxidases catalyze the glutathione- dependent reduction of organic peroxides and hydrogen peroxide . In the catalytic center they carry L - selenocysteine , a derivative of L - serine or L - cysteine . The phospholipid hydroperoxide glutathione peroxidase belongs to the family of glutathione peroxidases.

Glutathione peroxidases are particularly important as a component of the cellular defense against the consequences of oxidative stress . Disturbances in the function of such selenoproteins go hand in hand with deficiency syndromes such as Keshan and Kashin-Beck disease and may play a role in tumor development, in atherosclerosis and - in conjugation with 4-hydroxynonenals - in neurodegenerative diseases .

Catalyzed reaction

The reaction can be roughly divided into the following individual steps:

Enzyme-Selenocysteine-SeH + H ₂ O ₂ Enzyme-Selenocysteine-SeOH + H ₂ O ${\ displaystyle {\ ce {->}}}$

Enzyme-Selenocysteine-SeOH + GSH GS-Se-Selenocysteine-Enzyme + H ₂ O ${\ displaystyle {\ ce {->}}}$

GS-Se-Selenocysteine-Enzyme + GSH Enzyme-Selenocysteine-SeH + GSSG ${\ displaystyle {\ ce {->}}}$

The overall reaction is:

2 GSH + H ₂ O ₂ 2 H ₂ O + GSSG ${\ displaystyle {\ ce {->}}}$

The glutathione disulfide (GSSG) produced during the reaction is regenerated into two molecules of glutathione by the enzyme glutathione disulfide reductase using NADPH / H ⁺ as a reducing agent.

Web links

Wikibooks: Biochemistry and Pathobiochemistry: Glutathione Metabolism - Learning and Teaching Materials

Individual evidence

↑ K. Aoyama, K. Matsubara, S. Kobayashi: Aging and oxidative stress in progressive supranuclear palsy . In: Eur J Neurol. 13 (1), Jan 2006, pp. 89-92. (engl.)

[1] K. Aoyama, K. Matsubara, S. Kobayashi: Aging and oxidative stress in progressive supranuclear palsy . In: Eur J Neurol. 13 (1), Jan 2006, pp. 89-92. (engl.)