Palmitoyl-CoA

In today's article, we are going to further explore Palmitoyl-CoA, a topic that has been the subject of interest and debate for a long time. Palmitoyl-CoA is a topic that covers a wide variety of aspects, from its historical origins to its relevance in contemporary society. Over the years, Palmitoyl-CoA has sparked interest from professionals, academics, and enthusiasts alike, leading to numerous debates and research surrounding this topic. In this article, we are going to analyze different aspects of Palmitoyl-CoA, examining its impact, implications, and evolution over time. In addition, we will also explore the different perspectives and opinions that exist around Palmitoyl-CoA, with the aim of providing a global and complete vision on this topic. Get ready to enter the fascinating world of Palmitoyl-CoA!

Palmitoyl-CoA
Names
IUPAC name
3′-O-Phosphonoadenosine 5′-{(3R)-4-amino}-3-oxopropyl)amino]-3-hydroxy-2,2-dimethyl-4-oxobutyl dihydrogen diphosphate}
Systematic IUPAC name
O1-{methyl} O3-{(3R)-4-amino}-3-oxopropyl)amino]-3-hydroxy-2,2-dimethyl-4-oxobutyl} dihydrogen diphosphate
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.015.616 Edit this at Wikidata
KEGG
MeSH Palmitoyl+Coenzyme+A
  • InChI=1S/C37H66N7O17P3S/c1-4-5-6-7-8-9-10-11-12-13-14-15-16-17-28(46)65-21-20-39-27(45)18-19-40-35(49)32(48)37(2,3)23-58-64(55,56)61-63(53,54)57-22-26-31(60-62(50,51)52)30(47)36(59-26)44-25-43-29-33(38)41-24-42-34(29)44/h24-26,30-32,36,47-48H,4-23H2,1-3H3,(H,39,45)(H,40,49)(H,53,54)(H,55,56)(H2,38,41,42)(H2,50,51,52)/t26-,30-,31-,32+,36-/m1/s1 ☒N
    Key: MNBKLUUYKPBKDU-BBECNAHFSA-N ☒N
  • InChI=1/C37H66N7O17P3S/c1-4-5-6-7-8-9-10-11-12-13-14-15-16-17-28(46)65-21-20-39-27(45)18-19-40-35(49)32(48)37(2,3)23-58-64(55,56)61-63(53,54)57-22-26-31(60-62(50,51)52)30(47)36(59-26)44-25-43-29-33(38)41-24-42-34(29)44/h24-26,30-32,36,47-48H,4-23H2,1-3H3,(H,39,45)(H,40,49)(H,53,54)(H,55,56)(H2,38,41,42)(H2,50,51,52)/t26-,30-,31-,32+,36-/m1/s1
    Key: MNBKLUUYKPBKDU-BBECNAHFBL
  • CCCCCCCCCCCCCCCC(=O)SCCNC(=O)CCNC(=O)(C(C)(C)COP(=O)(O)OP(=O)(O)OC1(((O1)n2cnc3c2ncnc3N)O)OP(=O)(O)O)O
Properties
C37H66N7O17P3S
Molar mass 1005.95 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C , 100 kPa).
☒N verify (what is checkY☒N ?)

Palmitoyl-CoA is an acyl-CoA thioester. It is an "activated" form of palmitic acid and can be transported into the mitochondrial matrix by the carnitine shuttle system (which transports fatty acyl-CoA molecules into the mitochondria), and once inside can participate in beta-oxidation. Alternatively, palmitoyl-CoA is used as a substrate in the biosynthesis of sphingosine (this biosynthetic pathway does not require transfer into the mitochondria).[1][2]

Biosynthesis

Palmitoyl CoA formed from palmitic acid, in the reaction below.[3]

Palmitate + CoA-SH + ATP → Palmitoyl-CoA + AMP + Pyrophosphate

This reaction is often referred to as the "activation" of a fatty acid. The activation is catalyzed by palmitoyl-coenzyme A synthetase and the reaction proceeds through a two step mechanism, in which palmitoyl-AMP is an intermediate.[4] The reaction is driven to completion by the exergonic hydrolysis of pyrophosphate.[3]

The activation of fatty acids occurs in the cytosol and beta-oxidation occurs in the mitochondria. However, long chain fatty acyl-CoA cannot cross the mitochondrial membrane. If palmitoyl-CoA is to enter the mitochondria, it must react with carnitine in order to be transported across:

Palmitoyl-CoA + Carnitine ⇌ Palmitoyl-Carnitine + CoA-SH

This transesterification reaction is catalyzed by carnitine palmitoyl transferase.[5] Palmitoyl-Carnitine may translocate across the membrane, and once on matrix side, the reaction proceeds in reverse as CoA-SH is recombined with palmitoyl-CoA, and released. Unattached carnitine is then shuttled back to the cytosolic side of mitochondrial membrane.

Beta-oxidation

Once inside the mitochondrial matrix, palmitoyl-CoA may undergo β-oxidation. The full oxidation of palmitic acid (or palmitoyl-CoA) results in 8 acetyl-CoA's, 7 NADH, 7 H+, and 7 FADH2.[6] The full reaction is below:

Palmitoyl-CoA + 7 CoA-SH + 7 NAD+ + 7 FAD → 8 Acetyl-CoA + 7 NADH + 7 H+ + 7 FADH2

Sphingolipid biosynthesis

Palmitoyl-CoA is also the starting substrate, along with serine, for sphingolipid biosynthesis. Palmitoyl CoA and serine participate in a condensation reaction catalyzed by serine C-palmitoyltransferase (SPT), in which 3-ketosphinganine is formed. These reactions occur in the cytosol.[7]

Sphingosine synthesis

Additional images

See also

References

  1. ^ Brady, R.N.; DiMari, S.J.; Snell, E.E. (1969). "Biosynthesis of sphingolipid bases. 3. Isolation and characterization of ketonic intermediates in the synthesis of sphingosine and dihydrosphingosine by cell-free extracts of Hansenula ciferri". J. Biol. Chem. 244 (2): 491–496. doi:10.1016/S0021-9258(18)94455-8. PMID 4388074.
  2. ^ Stoffel, W.; Le Kim, D.; Sticht, G. (1968). "Biosynthesis of dihydrosphingosine in vitro". Hoppe-Seyler's Z. Physiol. Chem. 349 (5): 664–670. doi:10.1515/bchm2.1968.349.1.664. PMID 4386961.
  3. ^ a b Voet, Donald; Voet, Judith G.; Pratt, Charlotte W. (2016-02-29). Fundamentals of Biochemistry: Life at the Molecular Level. John Wiley & Sons. ISBN 978-1-118-91840-1.
  4. ^ Bar–Tana, J.; Rose, G.; Brandes, R.; Shapiro, B. (1973-02-01). "Palmitoyl-coenzyme A synthetase. Mechanism of reaction". Biochemical Journal. 131 (2): 199–209. doi:10.1042/bj1310199. ISSN 0264-6021. PMC 1177459. PMID 4722436.
  5. ^ Sharma, R. (2013), "Biochemical Mechanisms of Fatty Liver and Bioactive Foods", Bioactive Food as Dietary Interventions for Liver and Gastrointestinal Disease, Elsevier, pp. 709–741, doi:10.1016/b978-0-12-397154-8.00041-5, ISBN 978-0-12-397154-8
  6. ^ Kamel, Kamel S.; Halperin, Mitchell L. (2017), "Ketoacidosis", Fluid, Electrolyte and Acid-Base Physiology, Elsevier, pp. 99–139, doi:10.1016/b978-0-323-35515-5.00005-1, ISBN 978-0-323-35515-5
  7. ^ Michel, Christoph; van Echten-Deckert, Gerhild (1997-10-20). "Conversion of dihydroceramide to ceramide occurs at the cytosolic face of the endoplasmic reticulum". FEBS Letters. 416 (2): 153–155. Bibcode:1997FEBSL.416..153M. doi:10.1016/s0014-5793(97)01187-3. ISSN 0014-5793. PMID 9369202. S2CID 467943.