Prochlorococcusphage ferredoxin: structural characterization and electron transfer to cyanobacterial sulfite reductases
| Autor: | Dimithree Kahanda, George N. Phillips, George N. Bennett, Jose L. Olmos, Othneil N. Sparks, Joshua T. Atkinson, Jonathan J. Silberg, Weijun Xu, Mitchell D. Miller, Ian J. Campbell |
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| Rok vydání: | 2020 |
| Předmět: |
Cyanobacteria
0303 health sciences biology Structural similarity medicine.disease_cause biology.organism_classification Sulfite reductase 03 medical and health sciences chemistry.chemical_compound 0302 clinical medicine Sulfite chemistry Biochemistry medicine Prochlorococcus Escherichia coli 030217 neurology & neurosurgery Ferredoxin 030304 developmental biology Photosystem |
| DOI: | 10.1101/2020.02.07.937771 |
| Popis: | Marine cyanobacteria are infected by phage whose genomes encode ferredoxin (Fd) electron carriers. While these Fds are thought to redirect the energy harvested from light to phage-encoded oxidoreductases that enhance viral fitness, it is not clear how the biophysical properties and partner specificities of phage Fds relate to those in photosynthetic organisms. Bioinformatic analysis using a sequence similarity network revealed that phage Fds are most closely related to cyanobacterial Fds that transfer electrons from photosystems to oxidoreductases involved in nutrient assimilation. Structural analysis of myovirus P-SSM2 Fd (pssm2-Fd), which infectsProchlorococcus marinus, revealed high similarity to cyanobacterial Fds (≤0.5 Å RMSD). Additionally, pssm2-Fd exhibits a low midpoint reduction potential (−336 mV vs. SHE) similar to other photosynthetic Fds, albeit lower thermostability (Tm= 28°C) than many Fds. When expressed in anEscherichia colistrain with a sulfite assimilation defect, pssm2-Fd complemented growth when coexpressed with aProchlorococcus marinussulfite reductase, revealing that pssm2-Fd can transfer electrons to a host protein involved in nutrient assimilation. The high structural similarity with cyanobacterial Fds and reactivity with a host sulfite reductase suggest that phage Fds evolved to transfer electrons to cyanobacterial-encoded oxidoreductases. |
| Databáze: | OpenAIRE |
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