A: Secondary structural features of HGDC and its mutants.

<p>Mean residue molar ellipticities, in degrees, of A (Blue): G165fs; B (Violet): L45PL54P; C (Maroon): R140X; D (Brown): R77S; E (Grey): P24T; F (Black): WT; G (Olive): A36P; and H (Green): Y134A. Protein concentration in the case of WT, P24T, R77S, and A36P was 12 µM and in the case of R140X, G165fs, L45PL54P and Y134A it was 6 µM in 50 mM Tris buffer (pH 7.3). MRW = mean residue molecular weight, taken as 110 Da. The cell path length was 2 mm and all spectra were recorded at 37°C, corrected for background buffer signal and each reported spectrum is an average of 3 independent runs. <b>B: Tertiary structural features of HGDC and its mutants.</b> Ellipticities, in millidegrees, of A (Green): Y134A; B (Brown): R77S; C (Olive): A36P; D (Black): WT; and E (Green): P24T. Protein concentration in each case was 24 µM 50 mM Tris buffer (pH 7.3) and cell path length 10 mm, while the other conditions were maintained same as above. <b>C: Intrinsic fluorescence of HGDC and mutants.</b> I_f: emission intensity in arbitrary units. A (Grey): P24T; B (Brown): R77S; C (Black): WT; D Y134A; E (Violet): L45PL54P; F (Blue): G165fs; G (Maroon): R140X; and H (Olive): A36P: λ_exc: 295 nm, cell path length 3 mm, excitation and emission slits 2.5 nm recorded at room temperature. Each reported spectrum is an average of 3 independent runs.