Role of Photoisomerization on the Photodetachment of the Photoactive Yellow Protein Chromophore

Henley, Alice; Patel, Anand M.; Parkes, Michael A.; Anderson, James C.; Fielding, Helen H.

doi:10.1021/acs.jpca.8b07770

Cited by 13 publications

(26 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The more straightforward approaches include DFT (TD-DFT) [54] and ADC(2) [55,56] methods. We have found that the simpler TD-DFT method tends to yield VEEs that are consistently around 0.5 eV higher than those determined using higher level methods [23,25,28,29,34,35], but that the ADC(2) method compares favourably with high-level calculations, for example, with SA-CASSCF(14,12)-PT2/cc-pVDZ calculations [57] for a series of PYP chromophore anions (Table 2) [29], and XMCQDPT2/aug-cc-pVTZ level calculations [31] for the GFP chromophore anion [33]. However, due to the number of diffuse functions required in the basis set to obtain an accurate VEE, a huge number of continuum states are calculated.…”

Section: Computational Chemistry Considerationsmentioning

confidence: 71%

“…The resulting small droplets then evaporate further, eventually leading to the production of isolated gas-phase ions. ESI has been combined very successfully with photoelectron spectroscopy for studying the electronic structure of a wide range of deprotonated biomolecules, including protein chromophores [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35]. There are several techniques for measuring photoelectron spectra, the most popular of which are based on time-of-flight (TOF) or velocity map imaging (VMI) methods.…”

Section: Experimental Considerationsmentioning

confidence: 99%

“…PYP is an ideal system for studying biological photoreceptors as a result of its small size (125 residues), stability and ease of crystallisation [86][87][88][89][90]. Numerous spectroscopic and computational chemistry studies of the electronic structure and relaxation dynamics of isolated model PYP chromophores in the gas phase have been aimed at understanding the role of the chromophore and its environment in determining the function of this important photoreceptor [25,28,29,34…”

Section: Tuning Electronic Structure and Relaxation Dynamicsmentioning

confidence: 99%

“…Knowing that the structure of the chromophore and the protein environment play an important role in tuning the electronic relaxation dynamics has inspired several combined anion photoelectron spectroscopy and quantum chemistry investigations of structurally modified chromophores; examples include changing the position of the phenoxide group (oCAand mCA -) [25], substitution at the coumaryl tail (pCTand pCE -) [28] or introducing single-bond (PpCEand NpCE -) [29] or double-bond (EBpCE -) [34] 'locks' (Fig. 23).…”

Section: Tuning Electronic Structure and Relaxation Dynamicsmentioning

confidence: 99%

See 3 more Smart Citations

Anion photoelectron spectroscopy of protein chromophores

Henley

Fielding

2019

International Reviews in Physical Chemistry

Self Cite

View full text Add to dashboard Cite

Photoactive proteins that efficiently and selectively transfer light energy into a physical response are ubiquitous in nature. The small molecule chromophores that lie at the heart of these processes often exist as closed-shell anions following deprotonation in proton-transfer reactions. This review highlights the important role that anion photoelectron spectroscopy, combined with computational chemistry calculations, is playing in improving our understanding of the electronic structure and relaxation dynamics of these protein chromophores. We discuss key aspects of anion photoelectron spectroscopy. We then review recent anion photoelectron spectroscopy studies of the deprotonated chromophore anions found in green fluorescent protein (GFP), photoactive yellow protein (PYP) and the deprotonated oxyluciferin anion found in the luciferase enzyme.

show abstract

Section: Computational Chemistry Considerationsmentioning

confidence: 71%

Section: Experimental Considerationsmentioning

confidence: 99%

Section: Tuning Electronic Structure and Relaxation Dynamicsmentioning

confidence: 99%

Section: Tuning Electronic Structure and Relaxation Dynamicsmentioning

confidence: 99%

See 2 more Smart Citations

Anion photoelectron spectroscopy of protein chromophores

Henley

Fielding

2019

International Reviews in Physical Chemistry

Self Cite

View full text Add to dashboard Cite

show abstract

“…Broadening of photoelectron spectra following photoexcitation of resonances in the continuum has been observed in similar sized molecular anions by many other groups 14,30,31 including our own. 11,[32][33][34][35][36][37][38][39][40][41][42] This resonance in PhO − has been observed before 12,14 and assigned to indirect detachment from the S 1 (ππ * ) state of PhO − . The S 0 -S 1 (ππ * ) transition corresponds to promotion of an electron from the HOMO shown in Table 1 to the first antibonding orbital on the phenyl ring system (the LUMO of PhO − ) and therefore has shape resonance character with respect to the D 0 continuum.…”

Section: Photoelectron Spectramentioning

confidence: 86%

Photoelectron Imaging and Quantum Chemistry Study of Phenolate, Difluorophenolate, and Dimethoxyphenolate Anions

et al. 2019

Self Cite

View full text Add to dashboard Cite

Phenolates and their substituted analogues are important molecular motifs in many biological molecules, including the family of fluorescent proteins based on green fluorescent protein. We have used a combination of anion photoelectron velocity-map imaging measurements and quantum chemistry calculations to probe the electronic structure of the phenolate anion and difluoro-and dimethoxy-substituted analogues. We report vertical detachment energies (VDEs) and quantify the photoelectron angular distributions. The VDEs for phenolate (2.26 ± 0.03 eV, 3.22 ± 0.02 eV) are in agreement with high-resolution measurements, whereas the values for the substituted analogues (2.61 ± 0.03 eV for difluorophenolate; ∼ 2.35 eV for dimethoxyphenolate) are new measurements. We also report adiabatic excitation energies (AEEs) of anion resonances and discuss their contributions to the overall photoelectron angular distributions. The AEE of the lowest lying resonance in phenolate (∼ 3.36 eV) is consistent with previous measurements, whereas the value for the next resonance (∼ 3.7 eV) is a new measurement. The AEEs of the resonances in the substituted analogues (∼ 3.74 eV for difluorophenolate; ∼ 3.4 eV and 3.74 eV for dimethoxyphenolate) are new measurements.

show abstract

Measurement of the Population of Electrosprayed Deprotomers of Coumaric Acids Using UV–Vis Laser Photodissociation Spectroscopy

2021

View full text Add to dashboard Cite

The measurement of deprotonation sites in multifunctional molecules following electrospray ionization is important to better inform a wide range of spectroscopic and photophysical studies that use electrospray to prepare molecular species for study in the gas phase. We demonstrate that low-resolution UV–vis laser photodissociation spectroscopy can be applied in situ to identify the deprotomers of three coumaric acids, trans-para -coumaric acid (CMA), trans- caffeic acid (CA), and trans- ferulic acid (FA), formed via electrospray. Electronic absorption spectra of the deprotonated coumaric acids are recorded via photodepletion and photofragmentation following electrospray from solutions of ethanol and acetonitrile. By comparing the experimental spectra to wave function theory calculations, we are able to confirm the presence of phenoxide and carboxylate deprotomers upon electrospray for all three coumaric acids, when sprayed from both protic and aprotic solvents. Ratios of the phenoxide:carboxylate deprotomers are obtained by generating summed theoretical absorption spectra that reproduce the experimental spectra. We find that choice of electrospray solvent has little effect on the ratio of deprotomers obtained for deprotonated CMA and CA but has a greater impact for FA. Our results are in excellent agreement with previous work conducted on deprotonated CMA using IR spectroscopy and demonstrate that UV photodissociation spectroscopy of electrosprayed ions has potential as a diagnostic tool for identifying deprotomeric species.

show abstract

Role of Photoisomerization on the Photodetachment of the Photoactive Yellow Protein Chromophore

Cited by 13 publications

References 55 publications

Anion photoelectron spectroscopy of protein chromophores

Anion photoelectron spectroscopy of protein chromophores

Photoelectron Imaging and Quantum Chemistry Study of Phenolate, Difluorophenolate, and Dimethoxyphenolate Anions

Measurement of the Population of Electrosprayed Deprotomers of Coumaric Acids Using UV–Vis Laser Photodissociation Spectroscopy

Contact Info

Product

Resources

About