{"doi":"10.1111/j.1747-0285.2006.00423.x","title":"Examination of Two Independent Kinetic Assays for Determining the Inhibition of Carbonic Anhydrases I and II: Structure–Activity Comparison of Sulfamates and Sulfamides","abstract":"<jats:p>Enzyme inhibition assays often require deviations from physiological conditions. For carbonic anhydrases, procedures involving native CO<jats:sub>2</jats:sub> and non‐native substrates have been used. We compared a native and a non‐native substrate in the context of inhibition of human carbonic anhydrases I and II by examining various sulfamate and sulfamide compounds in two kinetic assays: hydration of CO<jats:sub>2</jats:sub> and hydrolysis of 4‐nitrophenylacetate. For carbonic anhydrase II, the two assays consistently generated similar <jats:italic>K</jats:italic><jats:sub>i</jats:sub> values, with the relative difference between the assays never exceeding 2.5‐fold. However, for carbonic anhydrase I there was more variability between the two assays, with <jats:italic>K</jats:italic><jats:sub>i</jats:sub> values for three compounds differing by more than 2.5‐fold, up to eightfold. In the CO<jats:sub>2</jats:sub> hydration assay, some sulfamates and sulfamides exhibited mixed kinetics or partial inhibition. Our results indicate that <jats:italic>K</jats:italic><jats:sub>i</jats:sub> or <jats:italic>K</jats:italic><jats:sub>d</jats:sub> values from carbonic anhydrase assays involving non‐native substrates should be confirmed by assays that use CO<jats:sub>2</jats:sub> (or HCO<jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" xlink:href=\"graphic/CBDD_423_mu1.gif\" xlink:title=\"inline image\" />), to establish pharmacological relevance. From structure–activity comparisons, the sulfamate is more effective than the sulfamide in inhibiting carbonic anhydrase I and II, but the sulfamate does not confer selectivity. In contrast, the sulfonamide confers selectivity for carbonic anhydrase I (10‐ to 30‐fold). Selectivity for carbonic anhydrase II occurred with the substituted fructose moiety, especially the <jats:sc>d</jats:sc>‐enantiomer (&gt;100‐fold).</jats:p>","journal":"Chemical Biology &amp; Drug Design","year":2006,"id":676542,"datarank":0.8724588353651117,"base_score":2.772588722239781,"endowment":2.772588722239781,"self_citation_contribution":0.41588830833596724,"citation_network_contribution":0.4565705270291445,"self_endowment_contribution":0.41588830833596724,"citer_contribution":0.4565705270291445,"corpus_percentile":null,"corpus_rank":null,"citation_count":15,"citer_count":9,"citers_with_citation_signal":8,"citers_with_endowment":8,"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":1767692,"name":"David F McComsey","orcid":null,"position":1,"is_corresponding":false},{"id":1767695,"name":"Virginia L Smith‐Swintosky","orcid":null,"position":2,"is_corresponding":false},{"id":1767698,"name":"Bruce E Maryanoff","orcid":null,"position":3,"is_corresponding":false},{"id":1767689,"name":"Richard P Shank","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"Examination of Two Independent Kinetic Assays for Determining the Inhibition of Carbonic Anhydrases I and II: Structure–Activity Comparison of Sulfamates and Sulfamides","abstract":"<jats:p>Enzyme inhibition assays often require deviations from physiological conditions. For carbonic anhydrases, procedures involving native CO<jats:sub>2</jats:sub> and non‐native substrates have been used. We compared a native and a non‐native substrate in the context of inhibition of human carbonic anhydrases I and II by examining various sulfamate and sulfamide compounds in two kinetic assays: hydration of CO<jats:sub>2</jats:sub> and hydrolysis of 4‐nitrophenylacetate. For carbonic anhydrase II, the two assays consistently generated similar <jats:italic>K</jats:italic><jats:sub>i</jats:sub> values, with the relative difference between the assays never exceeding 2.5‐fold. However, for carbonic anhydrase I there was more variability between the two assays, with <jats:italic>K</jats:italic><jats:sub>i</jats:sub> values for three compounds differing by more than 2.5‐fold, up to eightfold. In the CO<jats:sub>2</jats:sub> hydration assay, some sulfamates and sulfamides exhibited mixed kinetics or partial inhibition. Our results indicate that <jats:italic>K</jats:italic><jats:sub>i</jats:sub> or <jats:italic>K</jats:italic><jats:sub>d</jats:sub> values from carbonic anhydrase assays involving non‐native substrates should be confirmed by assays that use CO<jats:sub>2</jats:sub> (or HCO<jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" xlink:href=\"graphic/CBDD_423_mu1.gif\" xlink:title=\"inline image\" />), to establish pharmacological relevance. From structure–activity comparisons, the sulfamate is more effective than the sulfamide in inhibiting carbonic anhydrase I and II, but the sulfamate does not confer selectivity. In contrast, the sulfonamide confers selectivity for carbonic anhydrase I (10‐ to 30‐fold). Selectivity for carbonic anhydrase II occurred with the substituted fructose moiety, especially the <jats:sc>d</jats:sc>‐enantiomer (&gt;100‐fold).</jats:p>","is_dataset_classified":null,"base_score":2.772588722239781,"endowment":2.772588722239781,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"16999776","pmcid":null,"openalex_id":"https://openalex.org/W2144256341","authors":[],"funders":[],"total_grants":0,"fwci":0.7624,"citation_percentile":0.69302346,"influential_citations":0,"citation_trend":[{"year":2013,"count":2},{"year":2015,"count":1},{"year":2018,"count":1},{"year":2019,"count":1},{"year":2020,"count":2},{"year":2023,"count":1}],"oa_status":"closed","license":"http://onlinelibrary.wiley.com/termsAndConditions#vor","oa_locations":[{"url":"https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1747-0285.2006.00423.x","host_type":"publisher"},{"url":"https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1747-0285.2006.00423.x","host_type":"publisher"},{"url":"https://doi.org/10.1111/j.1747-0285.2006.00423.x","host_type":"journal"},{"url":"https://pubmed.ncbi.nlm.nih.gov/16999776","host_type":"repository"}],"fields_of_study":["Enzyme function and inhibition","Cholinesterase and Neurodegenerative Diseases","Synthesis and Catalytic Reactions"],"mesh_terms":["Carbonic Anhydrase Inhibitors","Kinetics","Structure-Activity Relationship","Sulfonic Acids","Carbonic Anhydrase I","Carbonic Anhydrase II"],"keywords":["Sulfamide","Carbonic anhydrase","Chemistry","Enzyme","Carbonic anhydrase II","Selectivity","Isozyme","Enzyme kinetics","Carbonic Anhydrase I","Stereochemistry","Biochemistry","Active site","Organic chemistry","Catalysis"],"sdg_mappings":[{"sdg_number":0,"sdg_label":"Clean water and sanitation"}],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-08-17T02:42:12.968094Z","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":[]}