2pp_2.Triacylglycerols

2pp_2.Triacylglycerols - 12/29/2009 2. Phospholipids,...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
12/29/2009 1 2. Phospholipids, triacylglycerols and complex lipids Membranes contain a variety of glycerophospholipids and sphingolipids CH 2 -O-C O CH-O-C O stearic acid (C18:0) 1-stearoyl-2-oleoyl- phosphatidylcholine other common glycerophospholipids: phosphatidyl ethanolamine phosphatidyl serine phosphatidyl glycerol oleic acid (C18:1( Δ 9 )) CH 2 -O-P-O-CH 2 CH 2 -N(CH 3 ) 3 O O phosphocholine glycerol + - sphingomyelin phosphatidyl inositol sphingolipids with carbohydrate groups serve as recognition factors on cell surfaces HO-CH CH-N-C O CH 2 -O-P-O-CH 2 CH 2 -N(CH 3 ) 3 O O H - +
Background image of page 1

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

View Full DocumentRight Arrow Icon
12/29/2009 2 Lipids in rat hepatocyte (liver cell) membranes The fluidity of a phospholipid bilayer increases at a characteristic temperature ( T m ), where the side chains become more disordered T m depends on the composition of the phospholipids. Phospholipids with unsaturated side chains or short side chains melt at lower temperatures Temperature Most natural unsaturated fatty acids have cis double bonds. Phospholipids with unsaturated fatty acid side chains don’t pack well with phospholipids that have saturated side chains. more saturated fats more unsaturated fats Temperature CO 2 - linolenic acid
Background image of page 2
12/29/2009 3 Unsaturated fatty acids and short-chain fatty acids make natural fats more fluid C16 & C18 saturated C16 & C18 unsaturated C4 to C14 saturated Cells adjust their phospholipid composition so that T m typically is slightly below the growth temperature 3 Ratio of unsaturated to saturated fatty 1 2 acids in E. coli grown at different temperatures Pig living outdoors in winter A.G. Marr & J.L. Ingraham, J. Bact. 84 : 1260 (1962) 10 20 30 40 0 Culture Temperature (C) cool warm
Background image of page 3

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

View Full DocumentRight Arrow Icon
12/29/2009 4 Animals snthesize oleic acid (C18:1) from stearoylCoA by an enzyme system that uses molecular O 2 as an oxidant CO-S-CoA O 2 + NADPH stearoylCoA, C18:0 CO-S-CoA oleoylCoA C18:1( Δ 9 ) 2H 2 O + NADP + This process occurs in the ER. The fatty acid and NADPH each provides two electrons for the reduction of O 2 to water, which requires 4 electrons:
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/08/2010 for the course LING 100 taught by Professor Kova during the Spring '10 term at University of Warsaw.

Page1 / 10

2pp_2.Triacylglycerols - 12/29/2009 2. Phospholipids,...

This preview shows document pages 1 - 5. Sign up to view the full document.

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