Bacteria produce diverse d-amino acids, which are essential components of cell wall peptidoglycan. Incorporation of these d-amino acids into peptidoglycan contributes to bacterial adaptation to environmental changes and threats. d-Amino acids have been associated with bacterial growth, biofilm formation and dispersal and regulation of peptidoglycan metabolism. The diversity of d-amino acids in bacteria is primarily due to the activities of amino acid racemases that catalyse the interconversion of the d- and l-enantiomers of amino acids. Recent studies have revealed that bacteria possess multiple enzymes with amino acid racemase activities. Therefore, elucidating d-amino acid metabolism by these enzymes is critical to understand the biological significance and behaviour of d-amino acids in bacteria. In this review, we focus on the metabolic pathways of d-amino acids in six types of bacteria.
Keywords: Thermotoga maritima; Thermus thermophilus; d-amino acid; amino acid racemase; bacteria.
© The Author(s) 2021. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.