Physical Sciences and Mathematics Commons^™

Site-Directed Mutagenesis Of Serine-72 Reveals The Location Of The Fructose 6-Phosphate Regulatory Site Of The Agrobacterium Tumefaciensadp-Glucose Pyrophosphorylase, Mashael Alghamdi Dr., Rania Ali Z Hussien, Yuanzhang Zheng, Hiral Patel, Matias D. Asencion Diez, Alberto A. Iglesias, Dali Liu, Miguel A. Ballicora

Chemistry: Faculty Publications and Other Works

The allosteric regulation of ADP–glucose pyrophosphorylase is critical for the biosynthesis of glycogen in bacteria and starch in plants. The enzyme from Agrobacterium tumefaciens is activated by fructose 6-phosphate (Fru6P) and pyruvate (Pyr). The Pyr site has been recently found, but the site where Fru6P binds has remained unknown. We hypothesize that a sulfate ion previously found in the crystal structure reveals a part of the regulatory site mimicking the presence of the phosphoryl moiety of the activator Fru6P. Ser72 interacts with this sulfate ion and, if the hypothesis is correct, Ser72 would affect the interaction with Fru6P and activation …