Phosphorescence properties of Trp-84 and Trp-310 in glyceraldehyde-3-phosphate dehydrogenase from Bacillus stearothermophilus.
The phosphorescence spectra of Trp-84 and Trp-310 in glyceraldehyde-3-phosphate dehydrogenase from Bacillus stearothermophilus in an aqueous glass show distinct 0,0 vibrational bands with peaks at 406.5 and 410.5 nm. With the aid of external heavy-atom perturbation of iodide and the thermal quenching profile, it is concluded that although both chromophores are effectively buried, only one, viz., the 406.5 nm component, is embedded in a sufficiently rigid core of the protein to phosphoresce in fluid solutions at room temperature. From inspection of the crystallographic structure is it evident that only Trp-310 embedded in the beta-sheet of the catalytic domain may satisfy the requirements of a long triplet-state lifetime and slow migration of O2 to its site. This identification confirms previous analysis of the phosphorescence properties of the enzymes from yeast, pig and rabbit muscle.
Gabellieri
E
E
CNR, Istituto di Biofisica, Pisa, Italy.
Strambini
G B
GB
D001411:Geobacillus stearothermophilus / Q000201:enzymology*; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000378:metabolism*; D007700:Kinetics; D008163:Luminescent Measurements; D013816:Thermodynamics; D014364:Tryptophan
D014364:Tryptophan; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases