Exact Mass: 291.1318
Exact Mass Matches: 291.1318
Found 13 metabolites which its exact mass value is equals to given mass value 291.1318,
within given mass tolerance error 0.001 dalton. Try search metabolite list with more accurate mass tolerance error
0.0002 dalton.
S-(2-Methylbutanoyl)-dihydrolipoamide
S-(2-Methylbutanoyl)-dihydrolipoamide-E is an intermediate in isoleucine degradation. S-(2-Methylbutanoyl)-dihydrolipoamide is normally conjugated to a lysine residue of the methylpropanoyltransferase enzyme (E stands for enzyme). The structure shown here is the free form. Specifically S-(2-Methylbutanoyl)-dihydrolipoamide-E is the 2-methylbutanoyl thioester of the reduced lipoyllysine residue in dihydrolipoyllysine-residue (2-methylpropanoyl)transferase. [HMDB] S-(2-Methylbutanoyl)-dihydrolipoamide-E is an intermediate in isoleucine degradation. S-(2-Methylbutanoyl)-dihydrolipoamide is normally conjugated to a lysine residue of the methylpropanoyltransferase enzyme (E stands for enzyme). The structure shown here is the free form. Specifically S-(2-Methylbutanoyl)-dihydrolipoamide-E is the 2-methylbutanoyl thioester of the reduced lipoyllysine residue in dihydrolipoyllysine-residue (2-methylpropanoyl)transferase.
S-(3-Methylbutanoyl)-dihydrolipoamide-E
S-(3-Methylbutanoyl)-dihydrolipoamide-E is an intermediate in valine, leucine and isoleucine degradation(KEGG ID C15975 ). It is the second to last step in the synthesis of branched chain fatty acid and is converted from 3-methyl-hydroxybutyl-ThPP via the enzyme 2-oxoisovalerate dehydrogenase [EC:1.2.4.4]. It is then converted to 3-methylbutanoyl-CoA via the enzyme dihydrolipoyllysine-residue (2-methylpropanoyl)transferase[EC:2.3.1.168]. [HMDB] S-(3-Methylbutanoyl)-dihydrolipoamide-E is an intermediate in valine, leucine and isoleucine degradation(KEGG ID C15975 ). It is the second to last step in the synthesis of branched chain fatty acid and is converted from 3-methyl-hydroxybutyl-ThPP via the enzyme 2-oxoisovalerate dehydrogenase [EC:1.2.4.4]. It is then converted to 3-methylbutanoyl-CoA via the enzyme dihydrolipoyllysine-residue (2-methylpropanoyl)transferase[EC:2.3.1.168].
2-hydroxy-3-methylbutanedioylcarnitine
2-hydroxy-3-methylbutanedioylcarnitine is an acylcarnitine. More specifically, it is an 2-hydroxy-3-methylbutanedioic acid ester of carnitine. Acylcarnitines were first discovered more than 70 year ago (PMID: 13825279). It is believed that there are more than 1000 types of acylcarnitines in the human body. The general role of acylcarnitines is to transport acyl-groups (organic acids and fatty acids) from the cytoplasm into the mitochondria so that they can be broken down to produce energy. This process is known as beta-oxidation. According to a recent review [Dambrova et al. 2021, Physiological Reviews], acylcarnitines (ACs) can be classified into 9 different categories depending on the type and size of their acyl-group: 1) short-chain ACs; 2) medium-chain ACs; 3) long-chain ACs; 4) very long-chain ACs; 5) hydroxy ACs; 6) branched chain ACs; 7) unsaturated ACs; 8) dicarboxylic ACs and 9) miscellaneous ACs. Short-chain ACs have acyl-groups with two to five carbons (C2-C5), medium-chain ACs have acyl-groups with six to thirteen carbons (C6-C13), long-chain ACs have acyl-groups with fourteen to twenty once carbons (C14-C21) and very long-chain ACs have acyl groups with more than 22 carbons. 2-hydroxy-3-methylbutanedioylcarnitine is therefore classified as a short chain AC. As a short-chain acylcarnitine 2-hydroxy-3-methylbutanedioylcarnitine is a member of the most abundant group of carnitines in the body, comprising more than 50\\% of all acylcarnitines quantified in tissues and biofluids (PMID: 31920980). Some short-chain carnitines have been studied as supplements or treatments for a number of diseases, including neurological disorders and inborn errors of metabolism. Carnitine acetyltransferase (CrAT, EC:2.3.1.7) is responsible for the synthesis of all short-chain and short branched-chain acylcarnitines (PMID: 23485643). The study of acylcarnitines is an active area of research and it is likely that many novel acylcarnitines will be discovered in the coming years. It is also likely that many novel roles in health and disease will be uncovered. An excellent review of the current state of knowledge for acylcarnitines is available at [Dambrova et al. 2021, Physiological Reviews].
