Streptococcus pneumoniae(2) PepS(1) aminoacyl-tRNA synthetases(1) PurC(1) triple-sieved interlock mechanism.(1) aspartate-biosynthetic pathway(1) aminopeptidases(1) cladosporin(1) peptidoglycan(1) SAICAR synthetase(1) malaria(1) molecular docking(1) structure-guided inhibitor development.(1) substrate-length selectivity(1) l,d-carboxypeptidase(1)