{"doi":"10.1021/jacs.5c08367","title":"Structural Basis for 3-Amino-3-carboxypropyl Transfer in Nocardicin Biosynthesis","abstract":"S -Adenosyl- l -methionine (SAM) is well-known as a methyl donor for methyltransferases but also functions as a 3-amino-3-carboxypropyl (3-ACP) donor for 3-ACP transferases. NAT is a 3-ACP transferase which accepts β-lactam antibiotic nocardicin G ( 1 ) and SAM to produce isonocardicin C. Due to the lack of structural information about this enzyme, its reaction mechanism has not been fully identified. In this study, we report two X-ray crystal structures of NAT, including its apo and complex structure with 1 and SAH. Examination of them identified the structural basis for substrate recognition. Comprehensive approach integrating site-directed mutagenesis, thermal shift assay, MD simulation, and QM/MM calculation revealed that the Cα-amino group of SAM functions as a Brønsted base to enhance the nucleophilicity of the C6′-OH of 1, with the assistance of E143, thereby facilitating S N 2 attack on the Cγ of SAM. This study presents structural and computational analysis leading to more precise understanding of 3-ACP transfer.","journal":"Journal of the American Chemical Society","year":2025,"id":532892,"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":3,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9514,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1414400,"name":"Masayuki Karasawa","orcid":"0000-0003-0803-999X","position":1,"is_corresponding":false},{"id":1414401,"name":"Zhiyang Quan","orcid":"0009-0009-9507-8794","position":2,"is_corresponding":false},{"id":356894,"name":"Takahiro Mori","orcid":"0000-0002-2754-5858","position":3,"is_corresponding":false},{"id":1414881,"name":"Masahiro Kanaida","orcid":null,"position":4,"is_corresponding":false},{"id":374335,"name":"Craig A. Townsend","orcid":"0000-0003-2795-7585","position":5,"is_corresponding":false},{"id":1414402,"name":"Tohru Terada","orcid":"0000-0002-7091-0646","position":6,"is_corresponding":false},{"id":356900,"name":"Ikuro Abe","orcid":"0000-0002-3640-888X","position":7,"is_corresponding":false},{"id":576240,"name":"Takayoshi Awakawa","orcid":"0000-0003-2575-3175","position":8,"is_corresponding":false},{"id":1414880,"name":"Yaojie Gao","orcid":null,"position":0,"is_corresponding":true}],"reference_count":31,"raw_metadata":null,"created_at":"2026-07-19T02:51:27.893975Z","pmid":"40921178","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":[]}