Open AccessIntermediate spectra and photocycle kinetics of the Asp96 → Asn mutant bacteriorhodopsin determined by singular value decomposition with self-modeling
Author(s) -
László Zimányi,
Ágnes Kulcsár,
Janos Κ. Lanyi,
Donald F. Sears,
Jack Saltiel
Publication year - 1999
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.96.8.4414
Subject(s) - bacteriorhodopsin , kinetics , photoexcitation , spectral line , stoichiometry , chemistry , singular value decomposition , crystallography , physics , mathematics , atomic physics , excited state , biochemistry , quantum mechanics , astronomy , algorithm , membrane
Singular value decomposition with self-modeling is applied to resolve the intermediate spectra and kinetics of the Asp96 → Asn mutant bacteriorhodopsin. The search for the difference spectra of the intermediates is performed in eigenvector space on the stoichiometric plane. The analysis of data at pH values ranging from 4 to 8 and temperatures between 5 and 25°C reveals significant, early partial recovery of the initial state after photoexcitation. The derived spectra are not biased by assumed photocycles. The intermediate spectra derived in the initial step differ from spectra determined in prior analyses, which results in intermediate concentrations with improved stoichiometric properties. Increasingly more accurate photocycles follow with increasing assumed complexity, of which parallel models are favored, consistent with recent, independent experimental evidence.