G. Andrew Woolley

Learn More
We have investigated the site-specific folding kinetics of a photoswitchable cross-linked alpha-helical peptide by using single (13)C = (18)O isotope labeling together with time-resolved IR spectroscopy. We observe that the folding times differ from site to site by a factor of eight at low temperatures (6 degrees C), whereas at high temperatures (45 degrees(More)
Most azobenzene-based photoswitches use UV light for photoisomerization. This can limit their application in biological systems, where UV light can trigger unwanted responses, including cellular apoptosis. We have found that substitution of all four ortho positions with methoxy groups in an amidoazobenzene derivative leads to a substantial (~35 nm) red(More)
Remarkable recent successes in structure determinations of voltage-gated channels, ligand-gated channels, mechanosensitive channels and proton channels have advanced our understanding of the molecular basis of ion channel gating substantially. Models have helped to clarify aspects of this process and are now being designed as sophisticated biomimetics for(More)
Covalent dimers of alamethicin form conducting structures with gating properties that permit measurement of current-voltage (I-V) relationships during the lifetime of a single channel. These I-V curves demonstrate that the alamethicin channel is a rectifier that passes current preferentially, with voltages of the same sign as that of the voltage that(More)
The design of new optogenetic tools for controlling protein function would be facilitated by the development of protein scaffolds that undergo large, well-defined structural changes upon exposure to light. Domain swapping, a process in which a structural element of a monomeric protein is replaced by the same element of another copy of the same protein,(More)
The peptide alamethicin forms channels with a variety of conductance states. Selective stabilization of a particular state should simplify the task of understanding conductance in terms of channel structure. We synthesized two different covalent dimers of alamethicin in which peptides were linked at their C-terminal ends by flexible tethers. Both dimeric(More)
Current approaches for optogenetic control of transcription do not mimic the activity of endogenous transcription factors, which act at numerous sites in the genome in a complex interplay with other factors. Optogenetic control of dominant negative versions of endogenous transcription factors provides a mechanism for mimicking the natural regulation of gene(More)
Spatially localized translation plays a vital role in the normal functioning of neuronal systems and is widely believed to be involved in both learning and memory formation. It is of central interest to understand both the phenomenon and molecular mechanisms of local translation using new tools and approaches. Caged compounds can, in principle, be used as(More)
The attempt frequency or prefactor (k0) of the transition-state rate equation of protein folding kinetics has been estimated to be on the order of 10(6) s(-1), which is many orders of magnitude smaller than that of chemical reactions. Herein we use the mini-protein Trp-cage to show that it is possible to significantly increase the value of k0 for a protein(More)
Synthetic photocontrolled proteins could be powerful tools for probing cellular chemistry. Several previous attempts to produce such systems by incorporating photoisomerizable chromophores into biomolecules have led to photocontrol but with incomplete reversibility, where the chromophore becomes trapped in one photoisomeric state. We report here the design(More)