ANL, Argonne National Laboratory; APS, Advanced Photon Source; Antibiotic; DHFS, dihydrofolate synthase; DHNA, dihydroneopterin aldolase; DHNP, 7,8-dihydroneopterin; DHPS, dihydropteroate synthase; DLS, dynamic light scattering; Dihydroneopterin aldolase; Dmax, maximum dimension; EcDHNA, Escherichia coli DHNA; FBDD, fragment-based drug discovery; Folate biosynthesis; Fragment-based drug discovery; GA, glycoaldehyde; HP, 6-hydroxymethyl-7,8-dihydropterin; HPPK, 6-hydroxymethyl-7,8-dihydropterin pyrophosphokinase; Helicobacter pylori; HpDHNA, Helicobacter pylori DHNA; ISCD, isozyme-specific contact distance; MW, molecular weight; MtDHNA, Mycobacterium tuberculosis DHNA; NP, neopterin; P(r), pair-distance distribution function; PCR, polymerase chain reaction; Rg, radius of gyration; SAXS, small-angle X-ray scattering; SER-CAT, Southeast Regional Collaborative Access Team; SaDHNA, Staphylococcus aureus DHNA; SpDHNA, Streptococcus pneumoniae DHNA; TCEP, tris(2-carboxyethyl)phosphine; TEV, tobacco etch virus; wwPDB, Worldwide Protein Data Bank