Since coenzyme A is, in chemical terms, a thiol, it can react with carboxylic acids to form thioesters, thus functioning as an acyl group carrier. It assists in transferring fatty acids from the cytoplasm to mitochondria.  A molecule of coenzyme A carrying an acyl group is also referred to as acyl-CoA. When it is not attached to an acyl group, it is usually referred to as CoASH or HSCoA. This process facilitates the production of fatty acids in cells, which are essential in cell membrane structure.
Coenzyme A is also the source of the phosphopantetheine group that is added as a prosthetic group to proteins such as acyl carrier protein and formyltetrahydrofolate dehydrogenase.