Final answer:
Palmitic acid (C16H3202) is the saturated C-16 fatty acid synthesized by adding two-carbon units derived from acetyl-CoA and malonyl-CoA onto a growing chain bound to an acyl carrier protein. The fatty acid synthase complex facilitates the synthesis, and after seven cycles, palmitoyl-ACP is formed and then released as a free fatty acid to form acyl-CoA.
Step-by-step explanation:
The saturated C-16 fatty acid synthesized by adding units of 2 carbons and an acetyl group aboard an acyl carrier protein (ACP) is called palmitic acid (hexadecanoic acid). During fatty acid synthesis, two carbon units are added to a growing fatty acid chain. Starting with an acetyl group, the process involves the repetitive addition of two-carbon units derived from malonyl-CoA (an acetylated form of CoA). The process is mediated by the fatty acid synthase (FAS) enzyme complex, which performs a series of reactions that extend the carbon chain bound to the ACP.
The crucial aspects of this process include the key roles of sulfhydryl groups provided by the phosphopantetheine group of ACP and the cysteine residue of the 3-ketoacyl-ACP synthase. The fatty acid synthase complex also includes acyl carrier protein (ACP) with its Pantetheine-SH group and Cysteine-SH group located in Ketoacyl synthase (KS). The comprehensive process not only involves an acyl group transfer but also the use of NADPH as a reducing agent.
This synthetic process culminates with the production of palmitoyl-ACP after seven cycles, resulting in a 16-carbon long saturated fatty acid. Following this, enzymes such as hydrolase release the free fatty acid from the ACP, and it rapidly forms an acyl-CoA for further cellular use.