Possible Interaction: Sodium Dodecyl Sulfate and Tryptophan

“The negative conformation-dependent CD bands at 210–225 nm of the … were more prominent than those of carboxypeptidase A. The effect of sodium dodecyl sulfate on the enzyme side chains, as expressed by the changes … bands at 286–294 nm, suggests the involvement of tryptophan residues in … interactions.”

“In summary, we conclude that internal concentration of tryptophan and tyrosine makes cells more resistant to detergent such as sodium dodecyl sulfate.”

“Therefore, we questioned the involvement of tryptophan in the response to sodium dodecyl sulfate treatment.”

“Among the peptides, Trp in position 1 becomes more motionally‐restricted in the presence of SDS , probably because this residue is located at the N‐terminal region, which presents higher conformational freedom to interact stronger with SDS molecules.”

“An enhancement in the α-helicity of protein with increasing concentration of SDS along with exposure of tryptophans is seen.”

“Importantly, substitution of Phe4 with Trp increased stability in SDS treatment.”

“Relative electrophoretic mobility and intrinsic fluorescence of tyrosine and tryptophan residues increased in a complex fashion as the SDS concentration was increased.”

“The disorganization of the native tertiary structure by SDS was expressed in a decrease of the circular dichroism bands related to the tyrosine and tryptophan chromophores and in appearance of the vibronic fine structure in the phenylalanine band zone.”

“Either tryptophan or α-methyltryptophan antagonizes this effect of SDS , i.e. a higher concentration of SDS is required to produce an equivalent response in the presence of either effector substance.”