Zachary Dobson
A5082263515- Photosynthetic Processes and Mechanisms
- Photoreceptor and optogenetics research
- Enzyme Structure and Function
- Algal biology and biofuel production
- Advanced Electron Microscopy Techniques and Applications
- Light effects on plants
- Bacteriophages and microbial interactions
- Advanced X-ray Imaging Techniques
- Biocrusts and Microbial Ecology
- Origins and Evolution of Life
- Pharmacological Effects of Natural Compounds
- Metal-Catalyzed Oxygenation Mechanisms
- Mitochondrial Function and Pathology
- Spectroscopy and Quantum Chemical Studies
- Porphyrin Metabolism and Disorders
Arizona State University
2019-2022
Cytochrome c oxidase (C O) reduces dioxygen to water and harnesses the chemical energy drive proton translocation across inner mitochondrial membrane by an unresolved mechanism. By using time-resolved serial femtosecond crystallography, we identified a key oxygen intermediate of bovine C O. It is assigned P R -intermediate, which characterized specific redox states metal centers distinct protein conformation. The heme 3 iron atom in ferryl (Fe 4+ = O 2− ) configuration, Cu B are oxidized...
Abstract The world’s first superconducting megahertz repetition rate hard X-ray free-electron laser (XFEL), the European XFEL, began operation in 2017, featuring a unique pulse train structure with 886 ns between pulses. With its rapid rate, XFEL may alleviate some of increasing demand for beamtime, particularly membrane protein serial femtosecond crystallography (SFX), leveraging orders-of-magnitude faster data collection. Here, we report SFX experiment, where determined 2.9 Å-resolution...
Since the first successful serial crystallography (SX) experiment at a synchrotron radiation source, popularity of this approach has continued to grow showing that third-generation synchrotrons can be viable alternatives scarce X-ray free-electron laser sources. Synchrotron flux may increased ∼100 times by moderate increase in bandwidth ('pink beam' conditions) some cost data analysis complexity. Here, we report high-viscosity injector-based pink-beam SX experiments. The structures...
Abstract Photosystem I coordinates more than 90 chlorophylls in its core antenna while achieving near perfect quantum efficiency. Low energy (also known as red chlorophylls) residing the are important for transfer dynamics and yield, however, their precise location remained elusive. Here, we construct a chimeric complex Synechocystis PCC 6803 that shows enhanced absorption spectral region. We combine Cryo-EM spectroscopy to determine structure − function relationship this red-shifted...
Photosynthetic organisms have adapted to survive a myriad of extreme environments from the earth's deserts its poles, yet proteins that carry out light reactions photosynthesis are highly conserved cyanobacteria modern day crops. To investigate adaptations photosynthetic machinery in excessive stress, we isolated new strain cyanobacteria, Cyanobacterium aponinum 0216, environment Sonoran Desert. Here report biochemical characterization and 2.7 Å resolution structure trimeric photosystem I...
Serial femtosecond crystallography (SFX) is a powerful technique that exploits X-ray free-electron lasers to determine the structure of macromolecules at room temperature. Despite impressive exposition structural details with this novel crystallographic approach, methods currently available introduce crystals into path beam sometimes exhibit serious drawbacks. Samples requiring liquid injection crystal slurries consume large quantities (at times up gram protein per data set), may not be...
An amendment to this paper has been published and can be accessed via a link at the top of paper.
Abstract The moss Physcomitrium patens diverged from green algae shortly after the colonization of land by ancient plants. This posed new environmental challenges which drove evolutionary processes. photosynthetic machinery modern flowering plants is adapted to high light conditions on land. Red shifted Lhca4 antennae are present in photosystem I harvesting complex many lineage but absent P. . Cryo-EM structure supercomplex (PSI-LHCI) at 2.8 Å reveals that replaced a unique Lhca2 paralogue...