Table 1 Summary of parameters obtained for the binding of ET and other ligands to wild-type and mutant SpEgtUC
From: Discovery and structure of a widespread bacterial ABC transporter specific for ergothioneine
SBD | ligand | Methoda | Ka (M−1) | ∆G (kcal mol−1) | ∆H (kcal mol−1) | –T∆S (kcal mol−1) | n |
|---|---|---|---|---|---|---|---|
SpEgtUC | ET | TYR | 2.0 ± 0.1 × 107 | –10.0 ± 0.1 | – | – | |
F277W/L374C- bimane SpEgtUC | ET | PiFQ | 2.0 ± 0.4 × 107 | –9.9 ± 0.1 | – | – | |
SpEgtUC | ET | ITC | 1.7 ± 0.1 × 107 | –9.9 ± 0.1 | –10.4 ± 0.1 | 0.5 ± 0.1 | 0.99 ± 0.01 |
SpEgtUCCTT | ET | ITC | 1.9 ± 0.1 × 107 | –9.9 ± 0.1 | –10.7 ± 0.4 | 0.8 ± 0.4 | 0.95 ± 0.04 |
SpEgtUC-GFP | ET | GFP | 1.2 ± 0.2 × 107 | –9.7 ± 0.1 | – | – | |
SpEgtUC-GFP | HER | GFP | 5.2 ± 0.5 × 103 | –5.1 ± 0.1 | – | – | |
SpEgtUC | HER | NMR | 6 ± 1 × 102 | –3.8 ± 0.1 | – | – | |
SpEgtUC | GB | NMR | <30 | <–2.0 | – | – | |
G244F SpEgtUC | ET | ITC | 2.0 ± 0.3 × 105 | –7.2 ± 0.1 | –8.2 ± 0.3 | 1.0 ± 0.2 | 0.88 ± 0.01 |
Y419F SpEgtUC | ET | ITC | 1.6 ± 0.1 × 106 | –8.5 ± 0.1 | –7.3 ± 0.5 | –1.2 ± 0.4 | 0.91 ± 0.02 |
F293Y SpEgtUC | ET | ITC | 2.0 ± 0.1 × 106 | –8.6 ± 0.3 | –9.9 ± 0.2 | 1.3 ± 0.2 | 1.06 ± 0.03 |
E375Q SpEgtUC | ET | ITC | 4.0 ± 0.2 × 104 | −6.3 ± 0.1 | –b | –b | 0.75 ± 0.03 |
EfEgtUC | ET | TYR | 1.6 ± 0.3 × 107 | –9.8 ± 0.1 | – | – | |
SaEgtUC | ET | TYR | 4.6 ± 1.6 × 106 | –9.1 ± 0.3 | – | – | |
LmEgtUC | ET | TYR | 1.8 ± 0.8 × 107 | –9.9 ± 0.4 | – | – |
