{"doi":"10.1101/2020.02.07.937771","title":"<i>Prochlorococcus</i> phage ferredoxin: structural characterization and electron transfer to cyanobacterial sulfite reductases","abstract":"Abstract 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 infects Prochlorococcus 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 (T m = 28°C) than many Fds. When expressed in an Escherichia coli strain with a sulfite assimilation defect, pssm2-Fd complemented growth when coexpressed with a Prochlorococcus marinus sulfite 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.","journal":"bioRxiv (Cold Spring Harbor Laboratory)","year":2020,"id":124593,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":2,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9548,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2020-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":409288,"name":"J.L. Olmos","orcid":"0000-0001-8400-0822","position":1,"is_corresponding":false},{"id":410478,"name":"Weijun Xu","orcid":null,"position":2,"is_corresponding":false},{"id":409289,"name":"Dimithree Kahanda","orcid":"0000-0002-0009-7450","position":3,"is_corresponding":false},{"id":409290,"name":"Joshua T. Atkinson","orcid":"0000-0001-9293-4123","position":4,"is_corresponding":false},{"id":409291,"name":"Othneil Noble Sparks","orcid":"0000-0002-4843-5009","position":5,"is_corresponding":false},{"id":409292,"name":"Mitchell D. Miller","orcid":"0000-0003-1626-4943","position":6,"is_corresponding":false},{"id":409293,"name":"G.N. Phillips","orcid":"0000-0002-4171-4603","position":7,"is_corresponding":false},{"id":409294,"name":"George N. Bennett","orcid":"0000-0003-1408-8915","position":8,"is_corresponding":false},{"id":409295,"name":"Jonathan J. Silberg","orcid":"0000-0001-5612-0667","position":9,"is_corresponding":false},{"id":409287,"name":"Ian Campbell","orcid":"0000-0003-3944-1260","position":0,"is_corresponding":true}],"reference_count":116,"raw_metadata":null,"created_at":"2026-07-18T23:15:11.632153Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}