[The effect of phalloidin on stability of F- and G-actin].
Intrinsic tryptophan fluorescence and fluorescence of a hydrophobic probe bis-ANS were used to study the effect of phalloidin, a bicyclic heptapeptide toxin, on stability of monomeric (G) and polymeric (F) actin. It was found that bis-ANS fluorescence is sensitive to the actin polymerization process. Phalloidin in concentrations from 1 to 2 molecules per 1 actin molecule shifts the thermally induced unfolding transition in F-actin toward about 15 degrees C higher temperatures. The stabilizing effect of phalloidin is even more evident in the case of urea denaturation of F-actin. Moreover, phalloidin stabilizes against denaturing by not only F-actin, but G-actin as well, showing direct stabilizing interactions between phalloidin and G-actin.
Vedenkina
N S
NS
Kalinichenko
L P
LP
Permiakov
E A
EA
D000199:Actins / Q000737:chemistry*; D000817:Anilino Naphthalenesulfonates; D005456:Fluorescent Dyes; D010590:Phalloidine / Q000737:chemistry*; D011489:Protein Denaturation; D017510:Protein Folding; D013050:Spectrometry, Fluorescence; D013696:Temperature
D000199:Actins; D000817:Anilino Naphthalenesulfonates; D005456:Fluorescent Dyes; D010590:Phalloidine; C035763:5,5'-bis(8-(phenylamino)-1-naphthalenesulfonate)
Vliianie falloidina na stabil'nost' F- i G-aktina.