4-Hydroxybutyrate dehydrogenase: Difference between revisions

Latest revision as of 11:28, 15 February 2025

4-Hydroxybutyrate dehydrogenase[edit]

Crystal structure of 4-Hydroxybutyrate dehydrogenase

4-Hydroxybutyrate dehydrogenase is an enzyme that catalyzes the oxidation of 4-hydroxybutyrate to succinate semialdehyde. This enzyme is part of the metabolic pathway involved in the degradation of gamma-hydroxybutyrate (GHB), a naturally occurring neurotransmitter and psychoactive drug.

Function[edit]

4-Hydroxybutyrate dehydrogenase plays a crucial role in the metabolism of GHB. It facilitates the conversion of 4-hydroxybutyrate, a metabolite of GHB, into succinate semialdehyde, which is then further oxidized to succinate, entering the citric acid cycle. This process is essential for the detoxification and clearance of GHB from the body.

Structure[edit]

The enzyme is a member of the short-chain dehydrogenase/reductase (SDR) family. It typically functions as a homodimer, with each subunit contributing to the active site. The crystal structure of 4-Hydroxybutyrate dehydrogenase, as shown in the image, reveals a typical SDR fold with a central beta-sheet flanked by alpha-helices.

Mechanism[edit]

The catalytic mechanism of 4-Hydroxybutyrate dehydrogenase involves the transfer of a hydride ion from the substrate to the cofactor NAD+, reducing it to NADH. This reaction is facilitated by a conserved tyrosine residue in the active site, which acts as a proton donor.

Clinical significance[edit]

Deficiency or malfunction of 4-Hydroxybutyrate dehydrogenase can lead to the accumulation of GHB, which may result in neurological symptoms due to its action as a central nervous system depressant. Understanding the function and regulation of this enzyme is important for developing treatments for conditions associated with GHB metabolism.

Related pages[edit]

@@ Line 1: / Line 1: @@
-{{Short description|Enzyme involved in the metabolism of gamma-hydroxybutyrate}}
+{{DISPLAYTITLE:4-Hydroxybutyrate dehydrogenase}}
-'''4-Hydroxybutyrate dehydrogenase''' is an enzyme that plays a crucial role in the [[metabolism]] of [[gamma-hydroxybutyrate]] (GHB), a naturally occurring [[neurotransmitter]] and [[psychoactive drug]]. This enzyme is responsible for the oxidation of 4-hydroxybutyrate to [[succinic semialdehyde]], which is a key step in the metabolic pathway of GHB.
+== 4-Hydroxybutyrate dehydrogenase ==
-==Structure==
+[[File:3pdu.jpg|thumb|right|Crystal structure of 4-Hydroxybutyrate dehydrogenase]]
--Hydroxybutyrate dehydrogenase is a member of the [[short-chain dehydrogenase/reductase]] (SDR) family of enzymes. It typically functions as a [[homotetramer]], meaning it is composed of four identical subunits. Each subunit contains a [[NAD+]] binding domain, which is essential for its enzymatic activity.
-==Function==
+'''4-Hydroxybutyrate dehydrogenase''' is an enzyme that catalyzes the oxidation of 4-hydroxybutyrate to succinate semialdehyde. This enzyme is part of the metabolic pathway involved in the degradation of gamma-hydroxybutyrate (GHB), a naturally occurring neurotransmitter and psychoactive drug.
-The primary function of 4-hydroxybutyrate dehydrogenase is to catalyze the conversion of 4-hydroxybutyrate to succinic semialdehyde. This reaction is part of the [[GABA shunt]], a metabolic pathway that links the metabolism of [[gamma-aminobutyric acid]] (GABA) with the [[tricarboxylic acid cycle]] (TCA cycle). The enzyme uses [[NAD+]] as a cofactor, which is reduced to [[NADH]] during the reaction.
-==Biological significance==
+== Function ==
--Hydroxybutyrate dehydrogenase is important for maintaining the balance of GHB and its metabolites in the body. GHB is both a neurotransmitter and a drug of abuse, and its levels are tightly regulated. The enzyme's activity ensures that excess GHB is metabolized efficiently, preventing potential toxic effects.
-==Clinical relevance==
+-Hydroxybutyrate dehydrogenase plays a crucial role in the [[metabolism]] of GHB. It facilitates the conversion of 4-hydroxybutyrate, a metabolite of GHB, into succinate semialdehyde, which is then further oxidized to succinate, entering the [[citric acid cycle]]. This process is essential for the detoxification and clearance of GHB from the body.
-Alterations in the activity of 4-hydroxybutyrate dehydrogenase can have significant clinical implications. Deficiencies in this enzyme may lead to the accumulation of GHB, which can result in [[neurological disorders]] and [[metabolic diseases]]. Understanding the function and regulation of this enzyme is important for developing therapeutic strategies for conditions associated with GHB dysregulation.
-==Related pages==
+== Structure ==
-* [[Gamma-hydroxybutyrate]]
+The enzyme is a member of the [[short-chain dehydrogenase/reductase]] (SDR) family. It typically functions as a homodimer, with each subunit contributing to the active site. The crystal structure of 4-Hydroxybutyrate dehydrogenase, as shown in the image, reveals a typical SDR fold with a central beta-sheet flanked by alpha-helices.
+== Mechanism ==
+The catalytic mechanism of 4-Hydroxybutyrate dehydrogenase involves the transfer of a hydride ion from the substrate to the cofactor [[NAD+]], reducing it to [[NADH]]. This reaction is facilitated by a conserved [[tyrosine]] residue in the active site, which acts as a proton donor.
+== Clinical significance ==
+Deficiency or malfunction of 4-Hydroxybutyrate dehydrogenase can lead to the accumulation of GHB, which may result in neurological symptoms due to its action as a [[central nervous system]] depressant. Understanding the function and regulation of this enzyme is important for developing treatments for conditions associated with GHB metabolism.
+== Related pages ==
+* [[Gamma-Hydroxybutyrate]]
+* [[Citric acid cycle]]
 * [[Short-chain dehydrogenase/reductase]]
-* [[GABA shunt]]
-* [[Tricarboxylic acid cycle]]
-==Gallery==
-<gallery>
-File:3pdu.jpg|Structure of 4-hydroxybutyrate dehydrogenase
-</gallery>
 [[Category:Enzymes]]
 [[Category:Metabolism]]
-[[Category:Neurotransmitters]]