The external aldimine form of the mutant beta-S377A Salmonella thypi tryptophan synthase in open conformation showing dual side chain conformations for the residue beta-Q114, sodium ion at the metal coordination site, and F9 inhibitor at the alpha-site. One of the beta-Q114 rotamer conformations allows a hydrogen bond to form with the PLP oxygen at the position 3 in the ring

2-({[4-(TRIFLUOROMETHOXY)PHENYL]SULFONYL}AMINO)ETHYL DIHYDROGEN PHOSPHATE
N-(4'-TRIFLUOROMETHOXYBENZENESULFONYL)-2-AMINO-1-ETHYLPHOSPHATE, F9

The external aldimine form of mutant beta-S377A Salmonella thypi tryptophan synthase in open conformation showing dual side chain conformations for the residue beta-Q114, sodium ion at the metal coordination site, and F9 inhibitor at the alpha-site. One of the beta-Q114 rotamer conformations allows a hydrogen bond to form with the PLP oxygen at the position 3 in the ring.

Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720)

50 mM Bicine-CsOH, 8% PEG 8,000, 6 mM Spermine, pH 7.6

National Institutes of Health/National Human Genome Research Institute (NIH/NHGRI)

WT, sodium ion, internal aldimine, 3 beta-Q114 rotamer conformation

mutant beta-S377A, cesium ion, external aldimine with inhibitor F9 at the alpha-site

mutant beta-Q114A, cesium ion, external aldimine with inhibitor F9 at the alpha-site

Solvent flattening and Histogram matching

alpha2-beta2 complex. Protein complex is a tetramer in solution and composed of two alpha-chains and two beta-chains.

protein complex, LYASE, F9F, internal aldimine