![]() |
![]() | This is the template sandbox page for Template:Leucine metabolism in humans (diff). |
![](http://upload.wikimedia.org/wikipedia/commons/thumb/4/43/Test_Template_Info-Icon_-_Version_%282%29.svg/50px-Test_Template_Info-Icon_-_Version_%282%29.svg.png)
To transclude this template as is, use:
{{Leucine metabolism in humans | note=yes}}
Important: If the note parameter is set to yes (
|note=yes
), the article receiving the transclusion from this template must have a reference group for "note" included in a "Notes" or "References" section at the end of the article (code: {{Reflist|group=note}}
).
Other optional parameters
To transclude this template with a different header, alignment, and/or caption, use:
{{Leucine metabolism in humans | header=(desired header) | header background=(color hex code) | align=(left/right/center) | caption=(desired caption)}}
The image's alternative text (i.e. |alt=
parameter) is "Diagram of leucine, HMB, and isovaleryl-CoA metabolism in humans".
References
- ^ "KEGG Reaction: R10759". Kyoto Encyclopedia of Genes and Genomes. Kanehisa Laboratories. Retrieved 24 June 2016.
- ^ Mock DM, Stratton SL, Horvath TD, Bogusiewicz A, Matthews NI, Henrich CL, Dawson AM, Spencer HJ, Owen SN, Boysen G, Moran JH (November 2011). "Urinary excretion of 3-hydroxyisovaleric acid and 3-hydroxyisovaleryl carnitine increases in response to a leucine challenge in marginally biotin-deficient humans". primary source. The Journal of Nutrition. 141 (11): 1925–1930. doi:10.3945/jn.111.146126. PMC 3192457. PMID 21918059.
Metabolic impairment diverts methylcrotonyl CoA to 3-hydroxyisovaleryl CoA in a reaction catalyzed by enoyl-CoA hydratase (22, 23). 3-Hydroxyisovaleryl CoA accumulation can inhibit cellular respiration either directly or via effects on the ratios of acyl CoA:free CoA if further metabolism and detoxification of 3-hydroxyisovaleryl CoA does not occur (22). The transfer to carnitine by 4 carnitine acyl-CoA transferases distributed in subcellular compartments likely serves as an important reservoir for acyl moieties (39–41). 3-Hydroxyisovaleryl CoA is likely detoxified by carnitine acetyltransferase producing 3HIA-carnitine, which is transported across the inner mitochondrial membrane (and hence effectively out of the mitochondria) via carnitine-acylcarnitine translocase (39). 3HIA-carnitine is thought to be either directly deacylated by a hydrolase to 3HIA or to undergo a second CoA exchange to again form 3-hydroxyisovaleryl CoA followed by release of 3HIA and free CoA by a thioesterase.
- ^ a b Wilson JM, Fitschen PJ, Campbell B, Wilson GJ, Zanchi N, Taylor L, Wilborn C, Kalman DS, Stout JR, Hoffman JR, Ziegenfuss TN, Lopez HL, Kreider RB, Smith-Ryan AE, Antonio J (February 2013). "International Society of Sports Nutrition Position Stand: beta-hydroxy-beta-methylbutyrate (HMB)". Journal of the International Society of Sports Nutrition. 10 (1): 6. doi:10.1186/1550-2783-10-6. PMC 3568064. PMID 23374455.
- ^ a b Kohlmeier M (May 2015). "Leucine". Nutrient Metabolism: Structures, Functions, and Genes (2nd ed.). Academic Press. pp. 385–388. ISBN 978-0-12-387784-0. Retrieved 6 June 2016.
Energy fuel: Eventually, most Leu is broken down, providing about 6.0kcal/g. About 60% of ingested Leu is oxidized within a few hours ... Ketogenesis: A significant proportion (40% of an ingested dose) is converted into acetyl-CoA and thereby contributes to the synthesis of ketones, steroids, fatty acids, and other compounds
Figure 8.57: Metabolism of L-leucine
- Notes
- ^ This reaction is catalyzed by an unknown thioesterase enzyme.[1][2]