Studies on the Biosynthesis of Pectinic Acid Methyl Esters.

Abstract
The labelled carbons of glycine-2-Cl4, serine-3-C14, formaldehyde-C14 and formate-C14 were incorporated into pectinic acid in radish plant metabolism. From 70 to 80% of the radioactivity of the pectinic acid was found in the methyl ester carbon after feeding glycine formaldehyde and formate, whereas, about 30 to 40% of the radioactivity was in the methyl ester carbon after feeding serine. When these methyl precursors were administered under similar conditions, formate was incorporated into methyl esters to the greatest extent, followed in order by formaldehyde, glycine and serine.