1jmh
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CONTRIBUTIONS OF ORIENTATION AND HYDROGEN BONDING TO CATALYSIS IN ASN-229 MUTANTS OF THYMIDYLATE SYNTHASE
OverviewOverview
We have determined structures of binary and ternary complexes of five, Asn229 variants of thymidylate synthase (TS) and related their structures, to the kinetic constants measured previously. Asn229 forms two hydrogen, bonds to the pyrimidine ring of the substrate, 2'-deoxyuridine-5'-monophosphate (dUMP). These hydrogen bonds constrain, the orientation of dUMP in binary complexes with dUMP, and in ternary, complexes with dUMP and the TS cofactor, 5,10-methylene-5,6,7,8-tetrahydrofolate. In N229 mutants, where these, hydrogen bonds cannot be made, dUMP binds in a misoriented or more, disordered fashion. Most N229 mutants exhibit no activity for the, dehalogenation of 5-bromo-dUMP, which requires correct orientation of dUMP, against Cys198. Since bound dUMP forms the binding surface against ... [(full description)]
About this StructureAbout this Structure
1JMH is a [Single protein] structure of sequence from [Lactobacillus casei] with UMP as [ligand]. Active as [Transferase], with EC number [2.1.1.45]. Structure known Active Site: CAT. Full crystallographic information is available from [OCA].
ReferenceReference
Contributions of orientation and hydrogen bonding to catalysis in Asn229 mutants of thymidylate synthase., Finer-Moore JS, Liu L, Birdsall DL, Brem R, Apfeld J, Santi DV, Stroud RM, J Mol Biol. 1998 Feb 13;276(1):113-29. PMID:9514716
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