biostudies-literatureKim JNational Research Foundation of Korea31442https://www.ebi.ac.uk/biostudies/studies/S-EPMC11682103biostudies-literatureUnknown14(1)Alanine racemase (Alr) catalyzes the pyridoxal 5'-phosphate (PLP)-dependent racemization between L- and D-alanine in bacteria. Owing to the potential interest in targeting Alr for antibacterial drug development, several studies have determined the structures of Alr from different species, proposing models for the reaction mechanism. Insights into its reaction dynamics may be conducive to a better understanding of the Alr reaction mechanism. In this study, we determined the structures of the apo and reaction states of Bacillus subtilis Alr (BsAlr) at room temperature using a fixed-target based X-ray free-electron laser. The 2.3 Å resolution structures revealed the alanine substrate or intermediate in various positions at the active site. Conformational change between the N- and C-terminal dScientific reportsExploring the reaction dynamics of alanine racemase using serial femtosecond crystallography.PMC116821032021R1I1A1A010508382021R1A2C301335711Chung WKNam KHCho YPark JLee KKim JfalseExploring the reaction dynamics of alanine racemase using serial femtosecond crystallography.Alanine racemase (Alr) catalyzes the pyridoxal 5'-phosphate (PLP)-dependent racemization between L- and D-alanine in bacteria. Owing to the potential interest in targeting Alr for antibacterial drug development, several studies have determined the structures of Alr from different species, proposing models for the reaction mechanism. Insights into its reaction dynamics may be conducive to a better understanding of the Alr reaction mechanism. In this study, we determined the structures of the apo and reaction states of Bacillus subtilis Alr (BsAlr) at room temperature using a fixed-target based X-ray free-electron laser. The 2.3 Å resolution structures revealed the alanine substrate or intermediate in various positions at the active site. Conformational change between the N- and C-terminal d2024-01-01T00:00:00Z2024 Dec2026-07-15T11:07:19.944Z2025-04-04T21:48:47.899ZS-EPMC116821033973314010.1038/s41598-024-83045-8