{"doi":"10.1002/anie.202015751","title":"Structural Characterization of Two CO Molecules Bound to the Nitrogenase Active Site","abstract":"As an approach towards unraveling the nitrogenase mechanism, we have studied the binding of CO to the active-site FeMo-cofactor. CO is not only an inhibitor of nitrogenase, but it is also a substrate, undergoing reduction to hydrocarbons (Fischer-Tropsch-type chemistry). The C-C bond forming capabilities of nitrogenase suggest that multiple CO or CO-derived ligands bind to the active site. Herein, we report a crystal structure with two CO ligands coordinated to the FeMo-cofactor of the molybdenum nitrogenase at 1.33 Å resolution. In addition to the previously observed bridging CO ligand between Fe2 and Fe6 of the FeMo-cofactor, a new ligand binding mode is revealed through a second CO ligand coordinated terminally to Fe6. While the relevance of this state to nitrogenase-catalyzed reactions remains to be established, it highlights the privileged roles for Fe2 and Fe6 in ligand binding, with multiple coordination modes available depending on the ligand and reaction conditions.","journal":"Angewandte Chemie International Edition","year":2020,"id":58752,"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":71,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9554,"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":309896,"name":"Kathryn Perez","orcid":null,"position":1,"is_corresponding":false},{"id":308220,"name":"Ailiena O. Maggiolo","orcid":"0000-0003-1707-5060","position":2,"is_corresponding":false},{"id":229093,"name":"Douglas C. Rees","orcid":"0000-0003-4073-1185","position":3,"is_corresponding":false},{"id":308221,"name":"Thomas Spatzal","orcid":"0000-0002-9136-5915","position":4,"is_corresponding":false},{"id":308219,"name":"Trixia M. Buscagan","orcid":"0000-0001-8242-9203","position":0,"is_corresponding":true}],"reference_count":50,"raw_metadata":null,"created_at":"2026-07-18T21:07:33.416320Z","pmid":"33320413","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":[]}