Observations on the composition and metabolism of the nitrogen-fixing root nodules of Myrica

Abstract
Nodules of Myrica gale were exposed to excess of 15N, after detachment from the plant, for periods of 45-120 min. The soluble N compounds were then extracted from the nodules and separated by chromato-graphic procedures. The amino acid composition of the extract was thus determined and it was found that asparagine was the predominant amino acid. Glutamine and various other amino acids were present in smaller amounts. The highest enrichment with 15N was found in the amide N of glutamine and the next highest in the amide N of asparagine and amino N of glutamic acid. The data are considered to support the view that the fixed N passes through the form of ammonia before entry into organic combination.