TY - JOUR
T1 - The identification of tryptophan residues responsible for atp-induced increase in intrinsic fluorescence of myosin subfragment 1
AU - Reshetnyak, Ya K.
AU - Andreev, O. A.
AU - Borejdo, J.
AU - Toptygin, D. D.
AU - Brand, L.
AU - Burstein, E. A.
N1 - Funding Information:
The authors are cordially thankful to Dr Boris P. Atanasov (Institute of Organic Chemistry, Bulgarian Academy of Sciences, Sofia, Bulgaria) for 3D models of viperotoxin subunits and to Drs Monique Laberge and Jane Vanderkooi (University of Pennsylvania, Philadelphia, PA) for the 3D model of cod parvalbumin. The work was supported by the grants: Russia Foundation for Basic Researches #97-04-49449 and 00-04-48127 (E.B. & Ya.R.); IUMBMB Wood/Whelan Fellowship (Ya.R.) and NIH grant AR40095-06 (J.B. & O.A.).
PY - 2000/8
Y1 - 2000/8
N2 - ATP binding to myosin subfragment 1 (S1) induces an increase in tryptophan fluorescence. Chymotryptic rabbit skeletal S1 has 5 tryptophan residues (Trp113, 131, 440, 510 and 595), and therefore the identification of tryptophan residues perturbed by ATP is quite complex. To solve this problem we resolved the complex fluorescence spectra into log-normal and decay-associated components, and carried out the structural analysis of the microenvironment of each tryptophan in S1. The decomposition of fluorescence spectra of S1 and S1-ATP complex revealed 3 components with maxima at ca. 318, 331 and 339–342 nm. The comparison of structural parameters of microenvironment of 5 tryptophan residues with the same parameters of single- tryptophan-containing proteins with well identified fluorescence properties applying statistical method of cluster analysis, enabled us to assign Trp595 to 318 nm, Trp440 to 331 nm, and Trp113, 131 and 510 to 342 nm spectral components. ATP induced an almost equal increase in the intensities of the intermediate (331 nm) and long-wavelength (342 nm) components, and a small decrease in the short component (318 nm). The increase in the intermediate component fluorescence most likely results from an immobilization of some quenching groups (Met437, Met441 and/or Arg444) in the environment of Trp440. The increase in the intensity and a blue shift of the long component might be associated with conformational changes in the vicinity of Trp510. However, these conclusions can not be extended directly to the other types of myosins due to the diversity in the tryptophan content and their microenvironments.
AB - ATP binding to myosin subfragment 1 (S1) induces an increase in tryptophan fluorescence. Chymotryptic rabbit skeletal S1 has 5 tryptophan residues (Trp113, 131, 440, 510 and 595), and therefore the identification of tryptophan residues perturbed by ATP is quite complex. To solve this problem we resolved the complex fluorescence spectra into log-normal and decay-associated components, and carried out the structural analysis of the microenvironment of each tryptophan in S1. The decomposition of fluorescence spectra of S1 and S1-ATP complex revealed 3 components with maxima at ca. 318, 331 and 339–342 nm. The comparison of structural parameters of microenvironment of 5 tryptophan residues with the same parameters of single- tryptophan-containing proteins with well identified fluorescence properties applying statistical method of cluster analysis, enabled us to assign Trp595 to 318 nm, Trp440 to 331 nm, and Trp113, 131 and 510 to 342 nm spectral components. ATP induced an almost equal increase in the intensities of the intermediate (331 nm) and long-wavelength (342 nm) components, and a small decrease in the short component (318 nm). The increase in the intermediate component fluorescence most likely results from an immobilization of some quenching groups (Met437, Met441 and/or Arg444) in the environment of Trp440. The increase in the intensity and a blue shift of the long component might be associated with conformational changes in the vicinity of Trp510. However, these conclusions can not be extended directly to the other types of myosins due to the diversity in the tryptophan content and their microenvironments.
UR - http://www.scopus.com/inward/record.url?scp=0033801573&partnerID=8YFLogxK
U2 - 10.1080/07391102.2000.10506651
DO - 10.1080/07391102.2000.10506651
M3 - Article
C2 - 11021656
AN - SCOPUS:0033801573
VL - 18
SP - 113
EP - 125
JO - Journal of Biomolecular Structure and Dynamics
JF - Journal of Biomolecular Structure and Dynamics
SN - 0739-1102
IS - 1
ER -