Effect of unfolding on the tryptophanyl fluorescence lifetime distribution in apomyoglobin

Bismuto, Ettore; Gratton, Enrico; Irace, Gaetano

doi:10.1021/bi00406a047

Cited by 44 publications

(29 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We have previously studied the temperature denaturation of apomyoglobin [15]. The general pattern is that as the temperature increases the width of the lifetime distribution decreases while in the native state, in accordance with our previous studies that show that a temperature increase causes a narrowing of the distribution.…”

Section: Introductionsupporting

confidence: 88%

Fluorescence lifetime distribution of folded and unfolded proteins

Gratton

Silva

Mei

et al. 1992

Int J of Quantum Chemistry

Self Cite

View full text Add to dashboard Cite

Time-resolved fluorescence of single tryptophan proteins have demonstrated the complexity of protein dynamic and protein structure. In particular, for some single tryptophan proteins, their fluorescence decay is best described by a distribution of fluorescence lifetimes rather than one or two lifetimes. Such results have provided further confirmation that the protein system is one which fluctuates between a hierarchy of many conformational substates. With this scenario as a theoretical framework, the correlations between protein dynamic and structure are investigated by studying the time-resolved fluorescence and anisotropy decay of holo and apo human superoxide dismutase (HSOD) at different denaturant concentrations. As a function of guanidine hydrochloride (GdHCI), the width of the fluorescence lifetime distribution of HSOD displays a maximum which is not coincident with the fully denatured form of HSOD at 6.5M GdHCI. Furthermore, the width of the fluorescence lifetime distribution for the fully denatured forms of holo and apo HSOD is greater than that of the native forms.

show abstract

Section: Introductionsupporting

confidence: 88%

Fluorescence lifetime distribution of folded and unfolded proteins

Gratton

Silva

Mei

et al. 1992

Int J of Quantum Chemistry

Self Cite

View full text Add to dashboard Cite

show abstract

“…We have chosen horse apoMb (h-apoMb) for our first experiment because a wealth of information on its cold denaturation (21), CD (22), millisecond folding dynamics (2), structure (23), molten globule states (24), and fluorescence properties (25) is available. Our cold denaturation data on h-apoMb are similar to the results obtained by Nishii and coworkers (22 (27,28).…”

Section: Steady-state Resultsmentioning

confidence: 99%

Direct observation of fast protein folding: the initial collapse of apomyoglobin.

Ballew

Sabelko

Gruebele³

1996

Proc. Natl. Acad. Sci. U.S.A.

318

298

View full text Add to dashboard Cite

The rapid refolding dynamics of apomyoglobin are followed by a new temperature-jump fluorescence technique on a 15-ns to 0. EXPERIMENTAL METHODSOutline. The heart of the experiment is shown in Fig. 1 Heating and Sample Cell. The sample is held in a custom 0.4-mm path length-fused silica cell (Fig. 1) cooled by two thermoelectric devices. The temperature is held constant to <0.2°C by a thermistor feedback loop. Two -120-mJ, 1.54-,um infrared beams are generated by Raman shifting a 700-mJ neodymium:yttrium/aluminum-garnet laser in a modeoptimized high-efficiency methane cell, resulting in uniform, near-gaussian heating profiles of 2-mm diameter. The counterpropagating beams are delayed by 8 ns from one another to avoid transient grating formation, and heating (by OH overtone relaxation in water) is completed within the pulse duration due to picosecond vibrational equilibration. The two mirror-image exponential absorption profiles add up to a longitudinal temperature uniformity of ±3% over the length of the cell, and the large uniform pump profile minimizes thermal lensing and diffusion effects. The T-jump is measured by transmission of a 1.5-,Lm diode laser focused to <400 tLm Abbreviations: T-jump, temperature jump; Mb, myoglobin; apoMb, apomyoglobin; h-apoMb, horse apoMb.

show abstract

“…The same effect has been observed on decreasing the solvent viscosity (Alcala et al, 1987b,c). By contrast, protein denaturation induces a broadening of the lifetime distribution due to the wider variety of environments experienced by tryptophan during the excited state (Bismuto et al, 1988). Since the rate of interconversion influences the width of the lifetime distribution, a higher degree of internal flexibility will determine a narrowing of the lifteime distribution bands.…”

Section: Resultsmentioning

confidence: 99%

Multiple conformational states in myoglobin revealed by frequency domain fluorometry

Bismuto

Irace²,

Gratton³

1989

Biochemistry

View full text Add to dashboard Cite

The tryptophanyl fluorescence decays of two myoglobins, i.e., sperm whale and tuna myoglobin, have been examined in the frequency domain with an apparatus which utilizes the harmonic content of a mode-locked laser. Data analysis was performed in terms of continuous distribution of lifetime having a Lorentzian shape. Data relative to sperm whale myoglobin, which possesses two tryptophanyl residues, i.e.,

show abstract

Effect of unfolding on the tryptophanyl fluorescence lifetime distribution in apomyoglobin

Cited by 44 publications

References 30 publications

Fluorescence lifetime distribution of folded and unfolded proteins

Fluorescence lifetime distribution of folded and unfolded proteins

Direct observation of fast protein folding: the initial collapse of apomyoglobin.

Multiple conformational states in myoglobin revealed by frequency domain fluorometry

Contact Info

Product

Resources

About