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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
51
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pubmed:dateCreated |
1999-1-26
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pubmed:abstractText |
The interaction between bovine pancreatic ribonuclease A (RNase A) and its RNA substrate extends beyond the scissile bond. Enzymic subsites interact with the bases and the phosphoryl groups of a bound substrate. We evaluated the four cationic residues closest to known subsites for their abilities to interact with a bound nucleic acid. Lys-37, Arg-39, Arg-85, and Lys-104 were replaced individually by an alanine residue, and the resulting enzymes were assayed as catalysts of poly(cytidylic acid) (poly(C)) cleavage. The values of Km and kcat/Km for poly(C) cleavage were affected only by replacing Arg-85. Moreover, the contribution of Arg-85 to the binding of the ground state and the transition state was uniform---Km increased by 15-fold and kcat/Km decreased by 10-fold. The contribution of Arg-85 to binding was also apparent in the values of Kd for complexes with oligonucleotides of different length. This contribution was dependent on salt concentration, as expected from a coulombic interaction between a cationic side chain and an anionic phosphoryl group. Together, these data indicate that Arg-85 interacts with a particular phosphoryl group of a bound nucleic acid. We propose that Arg-85 comprises a new distal subsite in RNase A---the P(-1) subsite.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Arginine,
http://linkedlifedata.com/resource/pubmed/chemical/Lysine,
http://linkedlifedata.com/resource/pubmed/chemical/Oligodeoxyribonucleotides,
http://linkedlifedata.com/resource/pubmed/chemical/Poly C,
http://linkedlifedata.com/resource/pubmed/chemical/Recombinant Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/Ribonuclease, Pancreatic
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pubmed:status |
MEDLINE
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pubmed:month |
Dec
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pubmed:issn |
0021-9258
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
18
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pubmed:volume |
273
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
34134-8
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pubmed:dateRevised |
2007-11-14
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pubmed:meshHeading |
pubmed-meshheading:9852072-Amino Acid Substitution,
pubmed-meshheading:9852072-Animals,
pubmed-meshheading:9852072-Arginine,
pubmed-meshheading:9852072-Base Sequence,
pubmed-meshheading:9852072-Binding Sites,
pubmed-meshheading:9852072-Cattle,
pubmed-meshheading:9852072-Kinetics,
pubmed-meshheading:9852072-Lysine,
pubmed-meshheading:9852072-Models, Molecular,
pubmed-meshheading:9852072-Mutagenesis, Site-Directed,
pubmed-meshheading:9852072-Oligodeoxyribonucleotides,
pubmed-meshheading:9852072-Point Mutation,
pubmed-meshheading:9852072-Poly C,
pubmed-meshheading:9852072-Protein Structure, Secondary,
pubmed-meshheading:9852072-Recombinant Proteins,
pubmed-meshheading:9852072-Ribonuclease, Pancreatic
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pubmed:year |
1998
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pubmed:articleTitle |
A new remote subsite in ribonuclease A.
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pubmed:affiliation |
Departments of Biochemistry and Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
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