EC Number   |
Protein Variants |
Reference |
|---|
    6.3.1.2 | A174S |
isoenzyme GLN1,3, 3.6fold increase in ratio of turnover-number to KM-value for NH4+ |
663076 |
| 6.3.1.2 | A305G |
mutation in the E304 flap, a flexible 7-residue loop over the entrance to the active site. 16% of wild-type activity with L-glutamate, 2% of wild-type activity with L-glutamine |
715370 |
| 6.3.1.2 | D50E |
mutant D50E shows activity with Mn2+ but very low activity with Mg2+, and altered kcat/Km values for all three substrates. Mutant E327A has a decreased kcat/Km value for NH4+ compared to that of the wild-type enzyme. Asp-50 is likely involved in binding NH4+ and may also play a role in catalyzing deprotonation of NH4+ to form NH3. Glu-327 participates in lowering the free energy of the transition state involved in formation of the positively charged tetrahedral adduct resulting from the condensation of gamma-glutamyl phosphate and NH3 |
37515 |
| 6.3.1.2 | D51A |
7% of activity in forward reaction, 4% of activity in reverse reaction no effect on protein structure |
655407 |
| 6.3.1.2 | D51E |
5% of activity in forward reaction, 87% of activity in reverse reaction no effect on protein structure |
655407 |
| 6.3.1.2 | D51N |
1.7% of activity in forward reaction, 2.4% of activity in reverse reaction no effect on protein structure |
655407 |
| 6.3.1.2 | D51R |
complete loss of activity, no effect on protein structure |
655407 |
| 6.3.1.2 | D51S |
24% of activity in forward reaction, 15% of activity in reverse reaction, no effect on protein structure |
655407 |
| 6.3.1.2 | D56A |
complete loss of activity in reverse reaction, 83% of wild-type activity in forward reaction, salting out at much higher ammonium sulfate concentrations than wild type enzyme |
655406 |
| 6.3.1.2 | D56E |
complete loss of activity in reverse reaction, 65% of wild-type activity in forward reaction, salting out properties only slightly affected |
655406 |
