Biopolymers and cell. 2000; 16 (3): 236

Proteins and cyanine dyes. 1. Asymmetrical carbocyanine dye 14K — a new fluorescent probe for homogeneous detection of proteins in solution

S. M. Yarmoluk

An interaction of carbocyanine 14K (6,8-diethyl-7-[E-3-(8-ethyl-7,8-dihydro-[l,3]-thiazolo-[4',5',3,4], benzo-(dj-[l,2,3]-thiadia-zolo-7-iliden)-l-propenyl]-6H-imidazolo-[4',S', 5, 6]tiodiazolo-8-ium iodide) with four proteins in both native and denatured states has been studied. The difference in fluorescent enhancement of this dye in the presence of various proteins has been shown. The fluorescence intensity of 14K in the presence of denatured proteins increased by 25—40 % in comparison with the fluorescence intensity of this dye in the complexes with corresponding native proteins. A possible mechanism of increasing the dye fluorescence under the interaction with proteins and nucleic acids has been proposed. The influence of different substances on fluorescent properties of 14K has been studied.