Leloir途径

Leloir途径(英語:The Leloir pathway)是降解D-半乳糖代謝途徑,以其发现者卢伊斯·弗德里科·莱洛伊尔(Luis Federico Leloir)命名。

Steps in the Leloir pathway of galactose metabolism.
Leloir途径代谢半乳糖的中间产物和酶[1]

首先,半乳糖变旋酶英语galactose mutarotase将β-D-半乳糖转化为α-D-半乳糖来激活这一途径。然后,α-D-半乳糖再由半乳糖激酶磷酸化半乳糖-1-磷酸。接下来,D-半乳糖-1-磷酸尿苷酰转移酶英语Galactose—1-phosphate uridylyltransferaseUDP-葡萄糖上的尿苷二磷酸基团转移到半乳糖-1-磷酸上形成UDP-半乳糖(另一个产物为D-葡萄糖-1-磷酸)。最后,UDP-葡萄糖-4-差向异构酶英语UDP-glucose 4-epimerase再将UDP-半乳糖转化为UDP-葡萄糖重回上一步反应。

另外,磷酸葡萄糖变位酶英语phosphoglucomutase还可以将D-葡萄糖-1-磷酸转化为D-葡萄糖-6-磷酸[2][3]

参考文献

  1. ^ Holden HM, Rayment I, Thoden JB. Structure and function of enzymes of the Leloir pathway for galactose metabolism. J. Biol. Chem. November 2003, 278 (45): 43885–8. PMID 12923184. doi:10.1074/jbc.R300025200. 
  2. ^ Frey PA. The Leloir pathway: a mechanistic imperative for three enzymes to change the stereochemical configuration of a single carbon in galactose. FASEB J. March 1996, 10 (4): 461–70 [2011-04-01]. PMID 8647345. 
  3. ^ Garrett, Reginald; Grisham, Charles M., Biochemistry 4, Cengage Learning: 556, 2010 [2014-10-13], ISBN 978-0-495-10935-8, (原始内容存档于2014-10-29)