PubMed:1954632 JSONTXT

{"project":"sentences","denotations":[{"id":"TextSentencer_T1","span":{"begin":0,"end":102},"obj":"Sentence"},{"id":"TextSentencer_T2","span":{"begin":103,"end":188},"obj":"Sentence"},{"id":"TextSentencer_T3","span":{"begin":189,"end":347},"obj":"Sentence"},{"id":"TextSentencer_T4","span":{"begin":348,"end":447},"obj":"Sentence"},{"id":"TextSentencer_T5","span":{"begin":448,"end":550},"obj":"Sentence"},{"id":"TextSentencer_T6","span":{"begin":551,"end":682},"obj":"Sentence"},{"id":"TextSentencer_T7","span":{"begin":683,"end":984},"obj":"Sentence"},{"id":"TextSentencer_T8","span":{"begin":985,"end":1261},"obj":"Sentence"},{"id":"T1","span":{"begin":0,"end":102},"obj":"Sentence"},{"id":"T2","span":{"begin":103,"end":188},"obj":"Sentence"},{"id":"T3","span":{"begin":189,"end":347},"obj":"Sentence"},{"id":"T4","span":{"begin":348,"end":447},"obj":"Sentence"},{"id":"T5","span":{"begin":448,"end":550},"obj":"Sentence"},{"id":"T6","span":{"begin":551,"end":682},"obj":"Sentence"},{"id":"T7","span":{"begin":683,"end":984},"obj":"Sentence"},{"id":"T8","span":{"begin":985,"end":1261},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"A bireactant, irreversible, active-site-directed inhibitor of beta-D-galactosidase (Escherichia coli). Synthesis and properties of (1/2,5,6)-2-(3-azibutylthio)-5,6-epoxy-3-cyclohexen-1-ol.\n(1/2,5,6)-2-(3-Azibutylthio)-5,6-epoxy-3-cyclohexen-1-ol (1) was synthesized and was found to irreversibly inactivate beta-D-galactosidase (Escherichia coli). The inactivation was prevented by the presence of isopropyl 1-thio-beta-D-galactopyranoside (IPTG). The vinyloxirane group of 1 reacted with water and other nucleophiles, especially at higher pH values. Reaction of 1 with beta-D-galactosidase was slow enough so that a competitive-inhibition constant (Ki) of 29mM could be determined. The inhibition constant for (1,2/3,6)-6-(3-azibutylthio)-2-bromo-4-cyclohexene-1,3-diol (2), the precursor of the bireactant inhibitor 1, was 13 mM, while that of (1,3/2,4)-3-(3-azibutylthio)-5-cyclohexene-1,2,4-triol (3), the product formed when the reactant is allowed to react with water, was 23mM. After irradiation by light, beta-D-galactosidase that had initially been treated with the bireactant compound and then digested with trypsin, showed a new pattern of elution from h.p.l.c., indicating that there was reaction at two regions of the beta-D-galactosidase molecule."}

{"project":"NCBITAXON","denotations":[{"id":"T1","span":{"begin":84,"end":100},"obj":"OrganismTaxon"},{"id":"T2","span":{"begin":329,"end":345},"obj":"OrganismTaxon"}],"attributes":[{"id":"A1","pred":"db_id","subj":"T1","obj":"562"},{"id":"A2","pred":"db_id","subj":"T2","obj":"562"}],"text":"A bireactant, irreversible, active-site-directed inhibitor of beta-D-galactosidase (Escherichia coli). Synthesis and properties of (1/2,5,6)-2-(3-azibutylthio)-5,6-epoxy-3-cyclohexen-1-ol.\n(1/2,5,6)-2-(3-Azibutylthio)-5,6-epoxy-3-cyclohexen-1-ol (1) was synthesized and was found to irreversibly inactivate beta-D-galactosidase (Escherichia coli). The inactivation was prevented by the presence of isopropyl 1-thio-beta-D-galactopyranoside (IPTG). The vinyloxirane group of 1 reacted with water and other nucleophiles, especially at higher pH values. Reaction of 1 with beta-D-galactosidase was slow enough so that a competitive-inhibition constant (Ki) of 29mM could be determined. The inhibition constant for (1,2/3,6)-6-(3-azibutylthio)-2-bromo-4-cyclohexene-1,3-diol (2), the precursor of the bireactant inhibitor 1, was 13 mM, while that of (1,3/2,4)-3-(3-azibutylthio)-5-cyclohexene-1,2,4-triol (3), the product formed when the reactant is allowed to react with water, was 23mM. After irradiation by light, beta-D-galactosidase that had initially been treated with the bireactant compound and then digested with trypsin, showed a new pattern of elution from h.p.l.c., indicating that there was reaction at two regions of the beta-D-galactosidase molecule."}