6VJV

Crystal structure of the Prochlorococcus phage (myovirus P-SSM2) ferredoxin at 1.6 Angstroms

Summary for 6VJV

• Entry DOI: 10.2210/pdb6vjv/pdb
• Descriptor: Ferredoxin, FE2/S2 (INORGANIC) CLUSTER, ACETATE ION, ... (5 entities in total)
• Functional Keywords: iron sulfur cluster binding, myovirus p-ssm2, prochlorococcus phage, ferredoxin, 2 iron 2 sulfur, electron transport
• Biological source: Prochlorococcus phage P-SSM2
• Total number of polymer chains: 2
• Total formula weight: 22266.05

Authors

Olmos Jr., J.L.,Campbell, I.J.,Miller, M.D.,Xu, W.,Kahanda, D.,Atkinson, J.T.,Sparks, N.,Bennett, G.N.,Silberg, J.J.,Phillips Jr., G.N. (deposition date: 2020-01-17, release date: 2020-02-19, Last modification date: 2023-10-11)

Primary citation

Campbell, I.J.,Olmos Jr., J.L.,Xu, W.,Kahanda, D.,Atkinson, J.T.,Sparks, O.N.,Miller, M.D.,Phillips Jr., G.N.,Bennett, G.N.,Silberg, J.J.
Prochlorococcusphage ferredoxin: structural characterization and electron transfer to cyanobacterial sulfite reductases.
J.Biol.Chem., 295:10610-10623, 2020

PubMed Abstract: Marine cyanobacteria are infected by phages whose genomes encode ferredoxin (Fd) electron carriers. These Fds are thought to redirect the energy harvested from light to phage-encoded oxidoreductases that enhance viral fitness, but it is unclear how the biophysical properties and partner specificities of phage Fds relate to those of photosynthetic organisms. Here, results of a bioinformatics 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 infects the cyanobacterium , revealed high levels of similarity to cyanobacterial Fds (root mean square deviations of ≤0.5 Å). Additionally, pssm2-Fd exhibited a low midpoint reduction potential (-336 mV a standard hydrogen electrode), similar to other photosynthetic Fds, although it had lower thermostability ( = 28 °C) than did many other Fds. When expressed in an strain deficient in sulfite assimilation, pssm2-Fd complemented bacterial growth when coexpressed with a sulfite reductase, revealing that pssm2-Fd can transfer electrons to a host protein involved in nutrient assimilation. The high levels of structural similarity with cyanobacterial Fds and reactivity with a host sulfite reductase suggest that phage Fds evolved to transfer electrons to cyanobacterially encoded oxidoreductases.

PubMed: 32434930
DOI: 10.1074/jbc.RA120.013501

Experimental method

X-RAY DIFFRACTION (1.59 Å)