Most of the fatty acids in animal consist of also variety of carbons in its parent chain. What home of such fatty acids reason the organic systems to choose them over the odd counterparts? What"s so poor around fatty acids containing odd variety of carbon atoms in their parent chain?

Why are fatty acids consisting of also number carbons in their parent chain predominant?


In short, it"s bereason fatty acids are made from two-carbon blocks.

The means that the majority of organisms make fatty acids is by the succeeding enhancement of two-carbon units (acetyl-CoA). So we generally acquire even-numbered fatty acids simply bereason the building blocks are also also.

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In plants and also in artificial conmessages, we can have actually some reactions that have the right to create odd-numbered fatty acids (by building through two-carbon units three times to obtain 6, and also then breaking that 6 in fifty percent to get 3, for example). Such odd fatty acids are viewed in some organisms, yet people are generally thought to acquire them from other resources (e.g. microbiota, diet).


Point 1: Fatty acids are mainly developed two-carbons at a time.

The European Bioinformatics Institute has a really excellent explanation of fatty acid synthesis. The quote listed below is from that (

"Whether existing as one complex or as independent enzymes, the reactions catalysed by types I and II fatty acid synthases are the very same. Both units are primed with acetyl-CoA, and also then add 2-carbon systems to the flourishing chain making use of malonyl-CoA as substrate."

Point 2: Odd-numbered fatty acids have the right to be developed by assorted organisms, and have the right to be attached to dysfeature in human beings.

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doi:10.1038/srep44845 talks about the importance of odd chain fatty acids in disease as a preface to its findings around the sources of such fatty acids. They attempt to narrowhead dvery own wbelow odd-chain fatty acids come from, but they definitely seem to be structure their case on the pretense that odd chain fatty acids are not great in people.

"According to the literary works, the beginning of C15:0 and also C17:0 has actually lengthy been attributed to the diet, specifically from ruminant fat as the major contributor in a typical Western diet. This has actually been described by the fact that these 2 OC-FAs are created by the rumales microbiome and also then included into the fat deposits of the organize pet destined for humale usage."

Point 3: Plants produce odd-chain fatty acids

An established/old paper (doi:10.1006/abbi.1994.1110) mentions this, and also there"s a Wikipedia short article ( that paraphrases in a nice way:

Some plant-based fatty acids, but, have actually an odd variety of carbon atoms, and also Phytanic fatty acid took in from plant chlorophyll has actually multiple methyl branch points. As a result, it breaks down right into 3 odd numbered 3C Propionyl segments and three also numbered 2C Acetyl segments and also one also numbered 4C Isobutynoyl segment.