{"doi":"10.1126/science.175.4024.901","title":"Reconstitution of Diphtheria Toxin from Two Nontoxic Cross-Reacting Mutant Proteins","abstract":"<jats:p>\n            The isolation of a new type of mutant Corynephage β, which carries a missense mutation in the structural gene for diphtheria toxin synthesis is described. The lysogenic C7\n            <jats:sub>8</jats:sub>\n            (β\n            <jats:sub>197</jats:sub>\n            )\n            <jats:sup>tox-crm+</jats:sup>\n            strain of\n            <jats:italic>Corynebacterium diphtheriae</jats:italic>\n            produces a nontoxic, extracellular protein of molecular weight 62,000. This protein is immunologically indistinguishable from toxin itself but inhibits the action of toxin on HeLa cells, probably by competing for attachment sites on the cell membrane. In contrast to fragment A derived from diphtheria toxin, fragment A\n            <jats:sub>197</jats:sub>\n            is unable to catalyze the inactivation of eucaryotic polypeptidyl-transfer RNA-transferase II. When mixtures of the two nontoxic mutant proteins, enzymically active crm\n            <jats:sub>45</jats:sub>\n            protein and enzymically inactive crm\n            <jats:sub>197</jats:sub>\n            protein, are subjected to mild treatment with trypsin in the presence of a thiol and then allowed to reoxidize after dialysis to remove excess thiol, \"diphtheria toxin\" is reconstituted in high yield.\n          </jats:p>","journal":"Science","year":1972,"id":688174,"datarank":0.7764224598860744,"base_score":5.176149732573829,"endowment":5.176149732573829,"self_citation_contribution":0.7764224598860744,"citation_network_contribution":0.0,"self_endowment_contribution":0.7764224598860744,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":176,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1616057,"name":"A. M. Pappenheimer","orcid":null,"position":1,"is_corresponding":false},{"id":1797794,"name":"Annabel Avery Harper","orcid":null,"position":2,"is_corresponding":false},{"id":1784991,"name":"Tsuyoshi Uchida","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"Reconstitution of Diphtheria Toxin from Two Nontoxic Cross-Reacting Mutant Proteins","abstract":"<jats:p>\n            The isolation of a new type of mutant Corynephage β, which carries a missense mutation in the structural gene for diphtheria toxin synthesis is described. The lysogenic C7\n            <jats:sub>8</jats:sub>\n            (β\n            <jats:sub>197</jats:sub>\n            )\n            <jats:sup>tox-crm+</jats:sup>\n            strain of\n            <jats:italic>Corynebacterium diphtheriae</jats:italic>\n            produces a nontoxic, extracellular protein of molecular weight 62,000. This protein is immunologically indistinguishable from toxin itself but inhibits the action of toxin on HeLa cells, probably by competing for attachment sites on the cell membrane. In contrast to fragment A derived from diphtheria toxin, fragment A\n            <jats:sub>197</jats:sub>\n            is unable to catalyze the inactivation of eucaryotic polypeptidyl-transfer RNA-transferase II. When mixtures of the two nontoxic mutant proteins, enzymically active crm\n            <jats:sub>45</jats:sub>\n            protein and enzymically inactive crm\n            <jats:sub>197</jats:sub>\n            protein, are subjected to mild treatment with trypsin in the presence of a thiol and then allowed to reoxidize after dialysis to remove excess thiol, \"diphtheria toxin\" is reconstituted in high yield.\n          </jats:p>","is_dataset_classified":null,"base_score":5.176149732573829,"endowment":5.176149732573829,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"4621498","pmcid":null,"openalex_id":"https://openalex.org/W2013811589","authors":[],"funders":[],"total_grants":0,"fwci":5.6393,"citation_percentile":0.95984186,"influential_citations":0,"citation_trend":[{"year":2012,"count":1},{"year":2013,"count":1},{"year":2014,"count":2},{"year":2015,"count":1},{"year":2016,"count":3},{"year":2017,"count":1},{"year":2018,"count":2},{"year":2020,"count":1},{"year":2023,"count":1},{"year":2026,"count":1}],"oa_status":"closed","license":null,"oa_locations":[{"url":"https://www.science.org/doi/pdf/10.1126/science.175.4024.901","host_type":"publisher"},{"url":"https://doi.org/10.1126/science.175.4024.901","host_type":"journal"},{"url":"https://pubmed.ncbi.nlm.nih.gov/4621498","host_type":"repository"}],"fields_of_study":["Toxin Mechanisms and Immunotoxins","Transgenic Plants and Applications","Diphtheria, Corynebacterium, and Tetanus","Adenosine Diphosphate","Animals","Autoradiography","Bacteriophages","Binding Sites","Carbon Isotopes","Cell Membrane","Corynebacterium diphtheriae","Diphtheria Toxin","Electrophoresis, Disc","Genes","Guinea Pigs","HeLa Cells","Leucine","Lysogeny","Molecular Weight","Mutation","Rabbits","Trypsin","Viral Proteins"],"mesh_terms":["Adenosine Diphosphate","Animals","Autoradiography","Bacteriophages","Binding Sites","Carbon Isotopes","Cell Membrane","Corynebacterium diphtheriae","Diphtheria Toxin","Electrophoresis, Disc","Genes","Guinea Pigs","HeLa Cells","Leucine","Lysogeny","Molecular Weight","Mutation","Rabbits","Trypsin","Viral Proteins","Hela Cells"],"keywords":["Diphtheria toxin","Corynebacterium diphtheriae","Mutant","Toxin","Chemistry","Biochemistry","Diphtheria","Microbiology","Molecular biology","Biology","Gene","Virology"],"sdg_mappings":[{"sdg_number":0,"sdg_label":"Life in Land"}],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-08-19T13:43:41.823808Z","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":[]}