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rdf:type |
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lifeskim:mentions |
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pubmed:issue |
1
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pubmed:dateCreated |
2001-8-16
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pubmed:abstractText |
Tyrosine feedback-inhibits the 3-deoxy-D-arabino-heptulosonate 7-phosphate (DAHP) synthase isoenzyme AroF of Escherichia coli. Here we show that an Asn-8 to Lys-8 substitution in AroF leads to a tyrosine-insensitive DAHP synthase. This mutant enzyme exhibited similar activities (v=30-40 U mg(-1)) and substrate affinities (K(m)(erythrose-4-phosphate)=0.5 mM, positive cooperativity with respect to phospho(enol)pyruvate) as the wild-type AroF, but showed decreased thermostability. An engineered AroF enzyme lacking the seven N-terminal residues also was tyrosine-resistant. These results strongly suggest that the N-terminus of AroF is involved in the molecular interactions occurring in the feedback-inhibition mechanism.
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pubmed:language |
eng
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pubmed:journal |
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pubmed:citationSubset |
IM
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pubmed:chemical |
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pubmed:status |
MEDLINE
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pubmed:month |
Aug
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pubmed:issn |
0378-1097
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pubmed:author |
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pubmed:issnType |
Print
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pubmed:day |
7
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pubmed:volume |
202
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
145-8
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pubmed:dateRevised |
2009-11-19
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pubmed:meshHeading |
pubmed-meshheading:11506923-3-Deoxy-7-Phosphoheptulonate Synthase,
pubmed-meshheading:11506923-Alleles,
pubmed-meshheading:11506923-Amino Acid Sequence,
pubmed-meshheading:11506923-Amino Acid Substitution,
pubmed-meshheading:11506923-Enzyme Stability,
pubmed-meshheading:11506923-Escherichia coli,
pubmed-meshheading:11506923-Feedback, Physiological,
pubmed-meshheading:11506923-Kinetics,
pubmed-meshheading:11506923-Mutation,
pubmed-meshheading:11506923-Sequence Homology, Amino Acid,
pubmed-meshheading:11506923-Sugar Phosphates,
pubmed-meshheading:11506923-Temperature,
pubmed-meshheading:11506923-Tyrosine
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pubmed:year |
2001
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pubmed:articleTitle |
Characterization of a new feedback-resistant 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase AroF of Escherichia coli.
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pubmed:affiliation |
Institut für Biotechnologie 1, Forschungszentrum Jülich GambH, Germany.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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