Crystal structure of the Apo form of D-Alanine:D-Alanine ligase (DDl) from Streptococcus mutans.
D-Alanine:D-Alanine ligase (DDl) catalyzes the formation of D-Alanine:D-Alanine
dipeptide and is an essential enzyme in bacterial cell wall biosynthesis.. This
enzyme does not have a human ortholog, making it an attractive target for
developing new antibiotic drugs. We determined the crystal structure at 2.23 A
resolution of DDl from Streptococcus mutans (SmDDl), the principal aetiological
agent of human dental caries. This structure reveals that SmDDl is a dimer and
has a disordered omega-loop region.