Seven D-amino acids, including D-valine, D-phenylalanine, D-leucine, D-isoleucine, D-tryptophan, D-methionine, and D-alpha-aminobutyric acid, are markedly less stimulative than the corresponding L-isomers that can stimulate the labellar sugar receptor of the fleshfly. A distinct effect of len;th of the amino acid side chain is clearly observed. Esterification and amidation of the alpha-carboxyl...

Soil and rhizosphere environments were examined in order to determine the identity and relative abundance of bacteria that catabolize d- and l-amino acids as the sole source of carbon and nitrogen. All substrates were readily catabolized by bacteria from both environments, with most d-amino acids giving similar CFU counts to their l-amino acid counterparts. CFU count ratios between l- and d-ami...

It has been believed that all living organisms are composed exclusively of L-amino acids, and that D-amino acids, which are the enantiomers of L-amino acids, were eliminated before the emergence of life. Therefore the presence and function of D-amino acids in living organisms except in the cell wall of microorganisms have not been studied. Recently, however, Daspartic acids (D-Asp) have been de...

D-amino acids, different from the ubiquitous L-amino are recognized as “unnatural” amino acids. The applications of acids have drawn increasing interest researchers in recent years, and widely used various industries, including for food products, pharmaceuticals, agricultural chemicals. Inspired by prevalent applications, many synthetic methods been developed, which mainly divided into chemical...

Liquid and syrupy dietary saps and juices of plant origin, characterized by the presence of large quantities of saccharides (glucose, fructose, or sucrose) and containing amino acids, were analyzed for the presence of D-amino acids using enantioselective gas chromatography-mass spectrometry. D-amino acids were detected in processed saps and juices of trees (maple, palm, birch), fruits (grape, a...

Background: Given the important role of amino acids in regulating many metabolic pathways of the body and considering the scarcity of markers for the diagnosis of inflammatory bowel disease (IBD) and its differentiation, we aimed to investigate the status of serum amino acids chromatography in children with IBD. Materials and Methods This case-control study was conducted among children with pri...

Amino acids have been regarded as potential plant nitrogen sources for more than a century. Some amino acids have been shown to support growth while others have growth-retarding effects. The D-isomers with notably adverse effects on plants’ growth and development include D-serine and D-alanine. Recently, D-serine has been recognised as an endogenous ligand of receptor channels mediating calcium...

Like mammals, insects need to ingest proteins from foods because they cannot synthesise several amino acids. Amino acids are also essential nutrients for Drosophila melanogaster, especially for female egg production, but how flies detect amino acids and how the feeding response to amino acids is regulated are unknown. In this study, the two-choice preference test, the proboscis extension reflex...

A wide variety of transaminase active on L-amino acids has been demonstrated in microorganisms (Feldman and Gunsalus, 1950; Fincham, 1951), mammalian tissues (Cammarata and Cohen, 1950; Rowsell, 1951), and plants (Wilson et al., 1954). Cohen (1939, 1940) did not find transaminase activity with any of several D-amino acids when he tested minced pigeon breast muscle or purified enzyme preparation...

The cephalochordate amphioxus is the closest invertebrate relative to vertebrates. In this study, using HPLC technique, free L-amino acids (L-AAs) and D-aspartic acid (D-Asp) have been detected in the nervous system of the amphioxus Branchiostoma lanceolatum. Among other amino acids glutamate, aspartate, glycine, alanine and serine are the amino acids found at the greatest concentrations. As it...