Dairy Chemistry And Biochemistry

MILK LIPIDS

Acyl Carrier Protein (ACP)

83

SH3 I

Acetyl-S-ACP I

ACP-SC=O + CH,

CoA-S-C=O

Malonyl-SACP

y3

c=o

ACP-S-C=O CH2 I I / + CO, + CoA-SH

bketobutyryl-S-ACP c=o

KR r""' NADP' + H+

7H3

HC-OH

I

I

CH2

I

ACP-SC=O

CH2

I

ACP-S-C=O

khy droxybutyryl-S-ACP

,733 7%

CH2

I

HD kHZ0

CH II ** 'HZ I

CH

ACP-S-C=O I NADPH + H+ NADP ACP-S-C=O

2, J-butenoyl-S-ACP

butyryl-S-ACP

CoA-S-C=O

Malonyl CoA

Figure 3.8 One complete cycle and the first step in the next cycle of the events during the
synthesis of fatty acids. ACP = acyl carrier protein, a complex of six enzymes: i.e. acetyl
CoA-ACP transacetylase (AT); malonyl CoA-ACP transferase (MT); B-keto-ACP synthase
(KS); 8-ketoacyl-ACP reductase (KR); p- hydroxyacyl-ACP-dehydrase (HD); enoyl-ACP
reductase (ER).