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sentences

Id Subject Object Predicate Lexical cue
T1 0-90 Sentence denotes Characteristics of guanosine triphosphate cyclohydrolase I purified from Escherichia coli.
T2 91-306 Sentence denotes GTP cyclohydrolase I, an enzyme that catalyzes the first reaction in the pathway for the biosynthesis of the pteridine portion of folic acid, was purified from Escherichia coli by 3,900-fold to apparent homogeneity.
T3 307-352 Sentence denotes Its molecular weight is estimated at 210,000.
T4 353-503 Sentence denotes At relatively high concentrations of salt (e.g. 0.3 M KCl) the enzyme can be dissociated into seemingly identical subunits of 51,000 molecular weight.
T5 504-545 Sentence denotes Removal of the salt allows reassociation.
T6 546-723 Sentence denotes GTP, ATP, and inorganic orthophosphate at concentration of 5 muM, 100muM, and 0.2 mM, respectively, promote the reassociation of the subunits even in the presence of 0.3 M salt.
T7 724-774 Sentence denotes The subunits have little or no catalytic activity.
T8 775-998 Sentence denotes When the enzyme was subjected to electrophoresis on polyacrylamide gel under denaturing conditions (in the presence of sodium dodecyl sulfate) only one protein band was evident; its molecular weight was estimated at 25,500.
T9 999-1080 Sentence denotes Proline was determined as the only NH2-terminal amino acid residue of the enzyme.
T10 1081-1224 Sentence denotes These observations suggest that the enzyme consists of four identical subunits and that each subunit contains two identical polypeptide chains.
T11 1225-1323 Sentence denotes Enough GTP was bound to the enzyme to suggest that each polypeptide contains one GTP binding site.
T12 1324-1357 Sentence denotes The Km value for GTP IS 0.02 MuM.
T13 1358-1493 Sentence denotes ATP, dGTP, and guanosine 5'-tetraphosphate are competitive inhibitors with Ki values of 0.25 muM, 0.24 muM, and 0.13 muM, respectively.
T14 1494-1539 Sentence denotes Orthophosphate is an uncompetitive inhibitor.
T15 1540-1615 Sentence denotes The enzyme is relatively heat-stable; its half-life at 82 degrees is 7 min.
T16 1616-1705 Sentence denotes Salt (NaCl, KCl, NH4Cl) at a concentration of 0.1 M activates the enzyme by 4- to 5-fold.
T17 1706-1889 Sentence denotes The only products of the action of the enzyme are formate and the triphosphoester of 2-amino-4-hydroxy-6-(D-erythro-1',2',3'-trihydroxypropyl)-7,8-dihydropteridine (H2-neopterin-PPP).
T18 1890-2033 Sentence denotes The evidence strongly suggests that this single enzyme catalyzes 4 independent chemical reactions in the conversion of GTP to H2-neopterin-PPP.
T1 0-90 Sentence denotes Characteristics of guanosine triphosphate cyclohydrolase I purified from Escherichia coli.
T2 91-306 Sentence denotes GTP cyclohydrolase I, an enzyme that catalyzes the first reaction in the pathway for the biosynthesis of the pteridine portion of folic acid, was purified from Escherichia coli by 3,900-fold to apparent homogeneity.
T3 307-352 Sentence denotes Its molecular weight is estimated at 210,000.
T4 353-503 Sentence denotes At relatively high concentrations of salt (e.g. 0.3 M KCl) the enzyme can be dissociated into seemingly identical subunits of 51,000 molecular weight.
T5 504-545 Sentence denotes Removal of the salt allows reassociation.
T6 546-723 Sentence denotes GTP, ATP, and inorganic orthophosphate at concentration of 5 muM, 100muM, and 0.2 mM, respectively, promote the reassociation of the subunits even in the presence of 0.3 M salt.
T7 724-774 Sentence denotes The subunits have little or no catalytic activity.
T8 775-998 Sentence denotes When the enzyme was subjected to electrophoresis on polyacrylamide gel under denaturing conditions (in the presence of sodium dodecyl sulfate) only one protein band was evident; its molecular weight was estimated at 25,500.
T9 999-1080 Sentence denotes Proline was determined as the only NH2-terminal amino acid residue of the enzyme.
T10 1081-1224 Sentence denotes These observations suggest that the enzyme consists of four identical subunits and that each subunit contains two identical polypeptide chains.
T11 1225-1323 Sentence denotes Enough GTP was bound to the enzyme to suggest that each polypeptide contains one GTP binding site.
T12 1324-1357 Sentence denotes The Km value for GTP IS 0.02 MuM.
T13 1358-1493 Sentence denotes ATP, dGTP, and guanosine 5'-tetraphosphate are competitive inhibitors with Ki values of 0.25 muM, 0.24 muM, and 0.13 muM, respectively.
T14 1494-1539 Sentence denotes Orthophosphate is an uncompetitive inhibitor.
T15 1540-1615 Sentence denotes The enzyme is relatively heat-stable; its half-life at 82 degrees is 7 min.
T16 1616-1705 Sentence denotes Salt (NaCl, KCl, NH4Cl) at a concentration of 0.1 M activates the enzyme by 4- to 5-fold.
T17 1706-1889 Sentence denotes The only products of the action of the enzyme are formate and the triphosphoester of 2-amino-4-hydroxy-6-(D-erythro-1',2',3'-trihydroxypropyl)-7,8-dihydropteridine (H2-neopterin-PPP).
T18 1890-2033 Sentence denotes The evidence strongly suggests that this single enzyme catalyzes 4 independent chemical reactions in the conversion of GTP to H2-neopterin-PPP.

NCBITAXON

Id Subject Object Predicate Lexical cue db_id
T1 73-89 OrganismTaxon denotes Escherichia coli 562
T2 251-267 OrganismTaxon denotes Escherichia coli 562

CL-cell

Id Subject Object Predicate Lexical cue cl_id
T1 935-939 Cell denotes band http://purl.obolibrary.org/obo/CL:0000560