Succinic acid semialdehyde

Biological. Heukelekian and Rand (1955) reported a 5-d BOD value of 1.31 g/g which is 58.7% of the ThOD value of 2.23 g/g. A Nocardia sp. isolated from soil was capable of transforming pyridine, in the presence of semicarbazide, into an intermediate product identified as succinic acid semialdehyde (Shukla and Kaul, 1986). 1,4-Dihydropyridine, glutaric dialdehyde, glutaric acid semialdehyde, and glutaric acid were identified as intermediate products when pyridine was degraded by Nocardiastiain Z1 (Watson and Cain, 1975). 

Suychnine IV-oxide, see Suychnine Succinic acid, see Aniline. Benzene, Cyclohexene Succinic acid semialdehyde, see Pyridine Styrene, see Ethylbenzene Succinate, see 2.4.5-T... 

The metabolic pathways involved in the synthesis of P(3HB-co-4HB) from 4-hydroxybutyric acid are shown in Fig. 2.4. Transferase or thiokinase catalyzes the conversion of 4-hydroxybutyric acid into 4HB-CoA, which is then used as the substrate by the PHA synthase in the polymerization reaction. The catabolism of 4-hydroxybutyric acid also leads to the formation of intermediates such as 3-hydroxybutyryl-CoA, resulting in the accumulation of P(3HB-co-4HB) copolymer. The main catabolic pathway for 4HB is probably via succinic acid semialdehyde and succinic acid pathways, which are catalyzed by 4HB dehydrogenase and succinic acid semialdehyde dehydrogenase (Valentin et al. 1995 Lutke-Eversloh and Steinbiichel 1999). All precursor substrates for the generation of 4HB monomers are first converted into 4HB-CoA, which is the immediate substrate for PHA synthase. 

Succinic acid, see 2-Chlorophenol. Cyclopentene, Maleic hvdrazide. 4-Nitrophenol, Phenol, 2,4.5-T Succinic semialdehyde, see Pyridine Succinyl-CoA, see Cyclohexane Sulfanilamide, see Asulam Sulfanilic acid, see Asulam Sulfonamide, see Prosulfuron Sulfonic acid, see Prosulfuron Sulfur, see Aldicarb. Benzene, Captan. Ferbam. 

GABA acts as an inhibitory transmitter in many different CNS pathways. It is subsequently destroyed by a transamination reaction (see Section 15.6) in which the amino group is transferred to 2-oxoglutaric acid, giving glutaric acid and succinic semialdehyde. This also requires PLP as a cofactor. Oxidation of the aldehyde group produces succinic acid, a Krebs cycle intermediate. 

GABA is converted to succinic semialdehyde [via GABA transaminase (GABAT) + pyri-doxal phosphate] which is thence oxidized to succinic acid which is further oxidized via the TCA cycle. 4-Hydroxybenzaldehyde from Gastrodia elata (Orchidaceae), a plant with antiepileptic properties, is an inhibitor of GABAT, as is the synthetic antiepileptic valproic acid (2-propenylpropanoic acid) (Table 6.6). 

Aminobutyric acid (No. 1771) (y-aminobutyric acid) is endogenous, as it is formed from decarboxylation of the essential amino acid glutamic acid. It undergoes transamination with a-ketoglutaric acid to re-form glutamic acid and succinic semialdehyde. This semialdehyde is then converted to succinic acid in a reaction... 

GABA is metabolized by GABA-T to succinic semialdehyde, which IS further oxidized by succinic semialdehyde dehydrogenase to succinic acid. Inhibition of GABA-T is therefore accompanied by an increase m GABA and this increase should reflect GABA turnover. The inhibition of GABA-T can be... 

Glutamic acid as an intermediate is formed from proline by the action of the cyclophorase system in the absence of AMP and Mg++. Under these conditions the oxidation is incomplete, and its accumulation was demonstrated by tests with the glutamic acid decarboxylase of E. coli, and by the action of chloramine-T, which yielded an equivalent amount of succinic acid. In addition to glutamic acid, a bisulfite-binding intermediate is produced in about equal amount, which may be glutamic semialdehyde. 

The first group of methods uses 1-iodo-6-m ethoxy naphthalene (2), which can be obtained either from Cleve s acid (1) [134-136] (Scheme 1) or from 2-aminonaphthalene (five stages, yield3%) [135]. In the conversion of (2) into (6), the C14 carbon atoms are introduced either successively in two steps or simultaneously in the form of four-carbon fragments. The reaction of the Grignard derivative (2) with the semialdehyde of succinic acid and the hydrogenation of the methyl ester of the acid formed (4) to y-(6-methoxy-l-napthyl)butyric acid (5) is an example of the simultaneous introduction of the atoms [134]. However, another method of syn-... 

Animals caimot synthesize the naphthoquinone ring of vitamin K, but necessary quantities are obtained by ingestion and from manufacture by intestinal flora. In plants and bacteria, the desired naphthoquinone ring is synthesized from 2-oxoglutaric acid (12) and shikimic acid (13) (71,72). Chorismic acid (14) reacts with a putative succinic semialdehyde TPP anion to form o-succinyl benzoic acid (73,74). In a second step, ortho-succmY benzoic acid is converted to the key intermediate, l,4-dihydroxy-2-naphthoic acid. Prenylation with phytyl pyrophosphate is followed by decarboxylation and methylation to complete the biosynthesis (75). 

Succinic semialdehyde (SSA) is synthesized in the mitochondria through transamination of y-aminobutyric acid (GABA) by GABA transaminase (GABA-T). Most of the SSA is oxidized by SSA dehydrogenase (SSA-DH) to form succinate, which is used for energy metabolism and results in the end products CO2 + H2O, which are expired. A small portion of SSA (<2%) is converted by SSA reductase (SSA-R) in the cytosol to GHB. GHB may also be oxidized back to SSA by GHB dehydrogenase (GHB-DH). 

Hydroxybutyric acid can also be directly incorporated [38], though some of it reacts with the corresponding enoyl-CoA. A more likely pathway proposed is via succinate semialdehyde, succinate, pyruvate, and acetyl-CoA, derived from 4-hydroxybutyrate, generally leading to a copolymer of 3-hydroxybutyryl and 4-hydroxybutyryl monomers from 4-hydroxybutyric acid [39]. 

Disorders of GABA Vitamin B6-dependent seizures Often an absence of succinic semialdehyde dehydrogenase Hypotonia, ataxia, mental retardation in older child. Increased urine 4-OH-butyric acid. Pyridoxine (B6-dependent disorder) Inhibitors of GABA transaminase... 

Succinic semialdehyde dehydrogenase deficiency. Patients have mental retardation, cerebellar disease, and hypotonia. They excrete large amounts of both succinic semialdehyde and 4-hydroxybutyric acid. There is no known therapy. 

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