Amino Acids of Colon and Rectum. Possible Involvement of Diaminopimelic Acid of Intestinal Bacteria in Antigenicity of Ulcerative Colitis Colon. ∗

Summary and Conclusions

In addition to 15 amino acids identified in normal and in ulcerative colitis colon mucosa, an amino acid, alpha-epsilon diaminopimelic acid, was demonstrated in some samples of ulcerative colitis rectal and colon tissue. This finding may be related to the presence of metabolic products of gram-negative intestinal bacteria. The supernates of disintegrated suspensions of spherophorus necrophorus and lysozyme digests of spherophorus necrophorus or B. proteus contain a component reacting similarly to colon mucosa with ulcerative colitis serum, as demonstrated by positive hemagglutination and agar gel diffusion reactions. Incubation of alpha-epsilon diaminopimelic acid and gamma-aminobutyric acid, with pepsin hydrolysates of globulin and colon tissue, yielded complexes also reacting as antigens with ulcerative colitis serum.

1. Fifteen amino acids were identified in hydrolysates of normal and ulcerative colitis rectal and colon mucosa and submucosa. 2. Rectal and colon tissue from patients with ulcerative colitis may contain an additional amino acid; possibly alpha-epsilon diaminopimelic acid, not yet demonstrated in normal colon tissue. 3. Alpha-epsilon diaminopimelic acid, a component of the cell wall of intestinal microorganisms, and perhaps other metabolic products of intestinal microorganisms, may contribute to the antigenic potential of ulcerative colitis colon.