A second allosteric site in Escherichia coli aspartate transcarbamoylase.
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ABSTRACT:
SUBMITTER: Peterson AW
PROVIDER: S-EPMC3428212 | biostudies-literature | 2012 Jun
REPOSITORIES: biostudies-literature
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A second allosteric site in Escherichia coli aspartate transcarbamoylase.
Peterson Alexis W AW Cockrell Gregory M GM Kantrowitz Evan R ER
Biochemistry 20120606 24
Escherichia coli aspartate transcarbamoylase is feedback inhibited by CTP and UTP in the presence of CTP. Here, we show by X-ray crystallography that UTP binds to a unique site on each regulatory chain of the enzyme that is near but not overlapping with the known CTP site. These results bring into question all of the previously proposed mechanisms of allosteric regulation in aspartate transcarbamoylase. ...[more]
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