Related Experiment Video
Updated: Jan 31, 2026

Antimicrobial Peptides Produced by Selective Pressure Incorporation of Non-canonical Amino Acids
Published on: May 4, 2018
Free D-amino acids produced by commensal bacteria in the colonic lumen
Mitsuharu Matsumoto1, Akihiro Kunisawa2,3, Takanari Hattori2,3
1Dairy Science and Technology Institute, Kyodo Milk Industry Co. Ltd, Tokyo, Japan. m-matumoto@meito.co.jp.
Abstract:
D-amino acids (D-AAs) have various biological activities, such as activation of N-methyl-D-aspartic acid (NMDA) receptor as a co-agonist by D-Ser. Since several free D-AAs are released in the broth monocultured with bacterium and D-AAs are probably utilized for bacterial communication, we presume that intestinal microbiota releases several kinds of free D-AAs, which may be involved in the hosts' health. However, presently, only four free D-AAs have been found in the ceacal lumen, but not in the colonic lumen. Here, we showed, by simultaneous analysis of chiral AAs using high-sensitivity liquid chromatography-tandem mass spectrometry (LC-MS/MS), that 12 free D-AAs (D-Ala, D-Arg, D-Asp, D-Gln, D-Glu, D-allo-Ile, D-Leu, D-Lys, D-Met, D-Phe, D-Ser, and D-Trp) are produced by intestinal microbiota and identified bacterial groups belonging to Firmicutes as the relevant bacterial candidates.
More Related Videos
Related Concept Videos
Amino acids
Amino Acid Catabolism
Amino Acid Biosynthetic Pathways
Phase II Reactions: Sulfation and Conjugation with α-Amino Acids
The Colonization of Land
The Roles of Bacteria and Fungi in Plant Nutrition

