metabolism_lecture_2+3 - Glycolysis (g lykys lys is , “s...

Info iconThis preview shows pages 1–13. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Glycolysis (g lykys lys is , “s plitting s ug a r”) Me ta bo lis m o f g luc o s e is a c e ntral re a c tio n in all king do m s o f life . “On alcoholic fermentation without yeast cells” (1897) • Eduard Buchner demonstrated for the first time that fermentation could take place outside living cells • Marked the end of vitalism and beginning of modern biochemistry Glucose rich in energy: C 6 H 12 O 6 + 6 O 2 6 CO 2 + 6 H 2 O ΔG’ = -2840 kJ/mol Chapter 14: Glycolysis Four major pathways of glucose utilization: • S to rag e in po lym e ric fo rm • Pe nto s e pho s pha te pa thway to g e ne ra te NADPH fo r de to xific a tio n a nd s ynthe s is o f lipids and nuc le o tide s • S ynthe s is o f s truc tura l po lys ac c haride s • Oxidation via glycolysis for short-term energy Tho s e inte rm e dia te s a re im po rta nt b e c a us e : • Plasma membrane lacks transporters for phosphorylated sugars • Phosphoryl groups are essential for energy conservation in metabolism • Binding of phosphate groups lowers activation energy and increases enzyme specificity Throughout these pathways, we find Phosporylated Intermediates Glycolysis: important structures 3-Phosphoglycerate Pyruvate Lactate D-Glyceraldehyde 3-phosphate Dihydroxyaceton phosphate D-Glucose-6-phosphate cyclic form open chain form Glycolysis: important reactions Phosphoryl transfer Phosphoryl shift Isomerization Dehydration Aldol cleavage Ke to s e Aldo s e Aldo s e Es te r Glycolysis overview: 2 phases 10 steps Pre pa ratio n pha s e Ac tiva te g luc o s e b y pho s pho ryl tra ns fe r Pa yo ff phas e C o lle c t e ne rg y fro m m e ta bo lite s o f a c tiva te d g luc o s e Glycolysis steps in detail: (fill in) ATP ATP 2 ATP 2 ATP 2 NADH (-16.7)-33.5 (+1.7)-2.5 (23.8)-1.3 (-14.2)-22.2 (+7.5) +2.5 (6.3)-1.7 (-18.8) +1.3 (4.6) +0.8 (1.7)-3.3 (-31.4)-16.7 Overview and energetics: everything x 2 helps to distinguish substrate and H 2 O, prevents wasteful ATP hydrolysis Hexokinase: big conformational change / induced fit upon substrate binding (8Å) 1 Mutiple isoenzymes in different tissues with different regulatory properties (hexokinase I and IV, see chapter 15). Hexokinase: big conformational change / induced fit upon substrate binding (8Å) Mutiple isoenzymes in different tissues with different regulatory properties (hexokinase I and IV, see chapter 15). helps to distinguish substrate and H 2 O, prevents wasteful ATP hydrolysis 1 Phosphohexose isomerase (glucose phosphate isomerase) C la s s ic e xa m ple fo r g e ne ra l ac id/b as e c a ta lys is b y a c tive -s ite G lu aldo s e ke to s e enediol Me c ha nis m : 2 Phosphofructokinase: 2 nd phosphorylation, the committed step...
View Full Document

This note was uploaded on 12/03/2009 for the course MCB 58168 taught by Professor Thorner during the Fall '09 term at University of California, Berkeley.

Page1 / 40

metabolism_lecture_2+3 - Glycolysis (g lykys lys is , “s...

This preview shows document pages 1 - 13. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online