Lecture 13 August 29, 2005 Lehninger (4 th Edition), Chapter

Skip the details on the metabolism of ketone bodies

Metabolic Biochemistry FATTY ACID SYNTHESIS LNC Chapter 21

LNC Fig the enzyme has three functional regions: - biotin carrier protein - biotin carboxylase - transcarboxylase acetyl-CoA + CO 2 ==> malonyl-CoA

LNC Fig. 21-4

acyl carrier protein LNC Fig. 21-2

End of lecture 12 August 26, 2005

LNC Fig. 21-2

This group is transferred to the other SH group to free the ACP-SH for the next malonyl group

LNC Fig. 21-3

LNC Fig. 21-5

LNC Fig beginning of the second round:

LNC Fig. 21-7

LNC Fig The normal product of fatty acid synthase is palmitate (16 carbons) elongation to stearate and longer chains takes place in the endoplasmic reticulum (ER) desaturation to oleate also occurs in the ER poly-unsaturated the shaded fatty acids are essential FA for humans but are made only in plants

Desaturation of fatty acids in vertebrates (in the smooth ER): requires molecular oxygen

LNC Fig. 21-8

Source of NADPH Malic enzyme is found in liver and other animal tissues A similar enzyme is found in bundle sheath cells in C4 plants LNC Fig. 21-9

Source of NADPH

photosynthesis

from glucose to fatty acids glucose pyruvate (in cytosol ) pyruvate acetyl-CoA (in mitochondria ) acetyl-CoA fatty acid (in cytosol ) How does acetyl-CoA come out of mitochondria ?

From glucose to fatty acids mitochondria cytosol LNC Fig

Biosynthesis of cholesterol steroids isoprenoids LNC pp. 799

LNC Fig

LNC Fig

CH 3 CH 3 CH 2 CCHCH 2 n Polyisoprene

LNC Fig

LNC Fig a

LNC Fig

LNC Fig

LNC Fig

LNC Fig

 3 - isopentenyl pyrophosphate LNC Fig STEROID HORMONES VITAMIN D RUBBER DOLICHOLS QUINONE OTHER VITAMINS CAROTENOIDS PLANT HORMONES C | CH 2 = C – CH 2 – CH 2 – O - P - O - P

Skip several pages in chapter 21 (pp ) read p. 785 about function/mechanism of aspirin, ibuprofen and other painkillers and related drugs

End of lecture 13 August 29, 2005