Lactate Racemization as a Rescue Pathway for Supplying d -Lactate to the Cell Wall Biosynthesis Machinery in Lactobacillus plantarum

• DOI: 10.1128/jb.187.19.6750-6761.2005
• Publication Date: 2005-09-15T19:42:50Z
• Authors: Philippe Goffin; Marie Deghorain; Jean-Luc Mainardi; Isabelle Tytgat; Marie-Christine C...; Michiel Kleerebezem; Pascal Hols
• Keywords: Amino Acids -- metabolism; 0301 basic medicine; Cell Wall -- metabolism; Racemases and Epimerases; Peptidoglycan; Operon -- physiology; L-Lactate Dehydrogenase -- genetics -- metabolism; Lactobacillus plantarum -- enzymology -- genetics; Racemases and Epimerases -- biosynthesis -- metabolism; 03 medical and health sciences; Cell Wall; LACTATE DESHYDROGENASE; Operon; Amino Acids; Cloning, Molecular; Peptide Synthases; MUTATION; Lactate Dehydrogenases; Lactate Dehydrogenases -- metabolism; Lactates -- chemistry -- metabolism; L-Lactate Dehydrogenase; Molecular; LACTATE RACEMASE; Peptide Synthases -- metabolism; CELL WALL BIOSYNTHESIS; LACTOBACILLUS PLANTARUM; Sciences bio-médicales et agricoles; VANCOMYCIN; PEPTIDOGLYCAN; 6. Clean water; ANTIBIOTIQUE RESISTANCE; Hydroxy Acids -- metabolism; [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology; Mutation; Peptidoglycan -- biosynthesis -- metabolism; Lactates; Hydroxy Acids; Cloning; Lactobacillus plantarum

Lactobacillus plantarum is a lactic acid bacterium that produces d- and l-lactate using stereospecific NAD-dependent lactate dehydrogenases (LdhD LdhL, respectively). However, reduction of glycolytic pyruvate by LdhD not the only pathway for d-lactate production since mutant defective in this activity still both isomers (T. Ferain, J. N. Hobbs, Jr., Richardson, Bernard, D. Garmyn, P. Hols, E. Allen, Delcour, Bacteriol. 178:5431-5437, 1996). Production species has been shown to be connected cell wall biosynthesis through its incorporation as last residue muramoyl-pentadepsipeptide peptidoglycan precursor. This particular feature leads natural resistance high concentrations vancomycin. In present study, we show L. possesses two pathways production: enzyme racemase, whose expression requires l-lactate. We report cloning six-gene operon, which involved racemization positively regulated Deletion operon an strain devoid exclusive As consequence, affected, growth dependent. also defect can partially restored d-alanyl-d-alanine-forming Ddl ligase from Lactococcus lactis, or supplementation with various d-2-hydroxy acids but d-2-amino acids, leading variable vancomycin levels. suggests unable efficiently synthesize precursors ending d-alanine machinery specifically dedicated d-lactate. context, racemase could thus provide rescue upon inactivation inhibition enzyme.