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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
5
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pubmed:dateCreated |
1997-6-3
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pubmed:abstractText |
Backbone-atom resonances have been assigned for both the substrate-free and the NADP+-complexed forms of UDP-N-acetylenolpyruvylglucosamine reductase (MurB), a monomeric, 347-residue (38.5 kDa) flavoenzyme essential for bacterial cell-wall biosynthesis. NMR studies were performed using perdeuterated, uniformly 13C/15N-labeled samples of MurB. In the case of substrate-free MurB, one or more backbone atoms have been assigned for 334 residues (96%). The assigned backbone atoms include 309 1HN and 15N atoms (94%), 315 13CO atoms (91%), 331 13C(alpha) atoms (95%), and 297 13C(beta) atoms (93%). For NADP+-complexed MurB, one or more backbone atoms have been assigned for 313 residues (90%); these include 283 1HN and 15N atoms (86%), 305 13CO atoms (88%), 310 13C(alpha) atoms (89%), and 269 13C(beta) atoms (84%). The strategies used for obtaining resonance assignments are described in detail. Information on the secondary structure in solution for both the substrate-free and NADP+-complexed forms of the enzyme has been derived both from 13C(alpha) and 13C(beta) chemical-shift deviations from random-coil values and from 1HN-1HN NOEs. These data are compared to X-ray crystallographic structures of substrate-free MurB and MurB complexed with the UDP-N-acetylglucosamine enolpyruvate (UNAGEP) substrate. NADP+ binding induces significant chemical-shift changes in residues both within the known UNAGEP and FAD binding pockets and within regions known to undergo conformational changes upon UNAGEP binding. The NMR data indicate that NADP+ and UNAGEP utilize the same binding pocket and, furthermore, that the binding of NADP+ induces structural changes in MurB. Finally, many of the residues within the UNAGEP/NADP+ binding pocket were difficult to assign due to dynamic processes which weaken and/or broaden the respective resonances. Overall, our results are consistent with MurB having a flexible active site.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Bacterial Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/Carbohydrate Dehydrogenases,
http://linkedlifedata.com/resource/pubmed/chemical/Carbon Isotopes,
http://linkedlifedata.com/resource/pubmed/chemical/Deuterium,
http://linkedlifedata.com/resource/pubmed/chemical/NADP,
http://linkedlifedata.com/resource/pubmed/chemical/Nitrogen Isotopes,
http://linkedlifedata.com/resource/pubmed/chemical/Recombinant Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/UDP-N-acetylmuramate dehydrogenase
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pubmed:status |
MEDLINE
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pubmed:month |
Apr
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pubmed:issn |
0022-2836
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
18
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pubmed:volume |
267
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
1223-46
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:9150408-Amino Acid Sequence,
pubmed-meshheading:9150408-Bacterial Proteins,
pubmed-meshheading:9150408-Carbohydrate Dehydrogenases,
pubmed-meshheading:9150408-Carbon Isotopes,
pubmed-meshheading:9150408-Deuterium,
pubmed-meshheading:9150408-Magnetic Resonance Spectroscopy,
pubmed-meshheading:9150408-Models, Molecular,
pubmed-meshheading:9150408-Molecular Sequence Data,
pubmed-meshheading:9150408-NADP,
pubmed-meshheading:9150408-Nitrogen Isotopes,
pubmed-meshheading:9150408-Protein Structure, Secondary,
pubmed-meshheading:9150408-Recombinant Proteins
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pubmed:year |
1997
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pubmed:articleTitle |
Characterization of NADP+ binding to perdeuterated MurB: backbone atom NMR assignments and chemical-shift changes.
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pubmed:affiliation |
Division of Macromolecular Structure, Bristol-Myers Squibb Pharmaceutical Research Institute, Princeton, NJ 08543-4000, USA.
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pubmed:publicationType |
Journal Article,
Comparative Study
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