Bamase—A Three-Tryptophan Protein

The emission intensity of wild-type bamase, which contains all duee tryptophan residues, increases dramatically 

Site-Directed Muts enesis of Tyrosine Protdns 

Protein Endneerii of Mutant Ribonuclease for Folding Exj riments 

Emission spei a ot RNase A with the trp 92 insertion are shown in Rgure 16.52. The excitation wavelengfo was 280 nm. so foat b osine and tryptophan are exched. The surprising feature of these spectra is foat foe tyrosine contribution is Inghest in foe native protein. This is the opposite of what is observed for most proteins. The reason for this unusual result is quenching, in foe folded state, of trp-92 by foe nearby aspartate residue. Hence, trp-92 b this engme ed protein provides a sensitive probe of protein folding, and its intensity increases nearly 100-fold when RNase A is unfolded. 

Ribose Binding Protein—Insertion of Tryptophan Residues in Eadt Domain 

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