[Distribution of tryptophan groups in molecules of troponin T, troponin I-troponin T complex, and alpha-actinin].
The method of fluorescence quenching was used to experimentally determine the distribution of tryptophan residues in molecules of troponin T, troponin T-troponin I complexes, and alpha-actinin. Iodide and cesium ions, and acrylamide were used as quenchers. It was shown that cesium ions decrease the fluorescence intensity of troponin T and its complex with troponin I by the mode of dynamic quenching. For alpha-actinin such a dynamic quencher is anionic iodide. By using the modified Stern-Volmer equation, the quenching was found to be about 90% of total fluorescence intensity for troponin T, approximately 70% for the troponin T-troponin I complexes, and 20% for alpha-actinin. The penetration of cesium ions to tryptophan 206 (tryptophan 204) in the troponin T-troponin I complex is hindered, probably due to the participation of this tryptophan in the formation of bonds between troponin subunits.
Gvritishvili
A G
AG
Institute of Molecular Biology and Biololical Physics, Georgian Academy of Sciences, ul. Gotua 12, Tbilisi, 380060 Georgia.
Simonishvili
S O
SO
Butkhuzi
N I
NI
Kuridze
K Sh
KSh
Simonidze
M Sh
MSh
But
E V
EV
Zaalishvili
M M
MM
D000185:Actinin / Q000737:chemistry*; D000818:Animals; D018482:Muscle, Skeletal / Q000737:chemistry; D011817:Rabbits; D013050:Spectrometry, Fluorescence; D019210:Troponin I / Q000737:chemistry*; D020107:Troponin T / Q000737:chemistry*; D014364:Tryptophan / Q000737:chemistry*
D019210:Troponin I; D020107:Troponin T; D000185:Actinin; D014364:Tryptophan