Disease relevance of glgC

• The nucleotide sequences of the Escherichia coli genome between the glycogen biosynthetic genes glgB and glgC, and 1170 bp of DNA which follows glgA have been determined [1].
• Site-directed mutagenesis of lysine382, the activator-binding site, of ADP-glucose pyrophosphorylase from Anabaena PCC 7120 [2].
• Characterization of a gene cluster for glycogen biosynthesis and a heterotetrameric ADP-glucose pyrophosphorylase from Bacillus stearothermophilus [3].

High impact information on glgC

• Temperature lability of ADP-glucose pyrophosphorylase (AGP; glucose-1-phosphate adenylyltransferase; ADP: alpha-D-glucose-1-phosphate adenylyltransferase, EC 2.7.7.27), a key starch biosynthetic enzyme, may play a significant role in the heat-induced loss in maize seed weight and yield [4].
• Analysis of allosteric effector binding sites of potato ADP-glucose pyrophosphorylase through reverse genetics [5].
• Aspartate residue 142 is important for catalysis by ADP-glucose pyrophosphorylase from Escherichia coli [6].
• Biosynthesis of bacterial glycogen. Mutagenesis of a catalytic site residue of ADP-glucose pyrophosphorylase from Escherichia coli [7].
• One cDNA plasmid, possessing about 1650 nucleotides, was shown by both DNA and RNA sequence analysis to contain the complete ADP-glucose pyrophosphorylase coding sequence of 483 amino acids [8].

Chemical compound and disease context of glgC

• Other studies show that for the SG14 enzyme the concentrations of ATP and Mg2+ in the synthesis direction and the concentrations of ADP-glucose and PPi in the pyrophosphorolysis direction required to give 50% of maximal activity are 3- to 6-fold higher than those observed for the parent E. coli B ADP-glucose pyrophosphorylase [9].
• On the basis of the above results and taking into account the reported concentrations of fructose-P2, of pyridoxal-P, and of the adenine nucleotide pool and its energy charge in E. coli strains, it is concluded that furctose-P2 is the important physiological allosteric activator of E. coli ADP-glucose pyrophosphorylase [9].
• ADP glucose pyrophosphorylase from Escherichia coli has been crystallized from polyethylene glycol 8000 solutions [10].
• Biosynthesis of bacterial glycogen. Incorporation of pyridoxal phosphate into the allosteric activator site and an ADP-glucose-protected pyridoxal phosphate binding site of Escherichia coli B ADP-glucose synthase [11].
• To elucidate the function that Asp(142) might play in the E. coli ADP-glucose pyrophosphorylase, aspartate was replaced by alanine, asparagine, or glutamate using site-directed mutagenesis [6].

Biological context of glgC

• The region between glgB and glgC contains an open reading frame (ORF) of 1521 bp which we call glgX [1].
• Thus both allosteric regulation of the ADP-glucose pyrophosphorylase as well as the genetic regulation of the biosynthesis of the glycogen biosynthetic enzymes are involved in the regulation of glycogen accumulation in E. coli B [9].
• Rice seed ADP-glucose pyrophosphorylase cDNA clones were isolated by screening a lambda expression library prepared from rice endosperm poly(A+) RNA with a heterologous antibody raised against the spinach leaf enzyme and subsequently by nucleic acid hybridization [8].
• A cDNA clone, blpl14, corresponding to the large subunit of ADP-glucose pyrophosphorylase (AGPase), has been isolated from a cDNA library prepared from leaves of barley (Hordeum vulgare L.). An open reading frame encodes a protein of 503 aa, with a calculated molecular weight of 54815 [12].
• The effects of amino acid substitutions at residue 295 on the regulatory properties of Escherichia coli ADP-glucose pyrophosphorylase were studied [13].

Associations of glgC with chemical compounds

• Kinetic studies with ADP-glucose synthase show that 1,6-hexanediol bisphosphate (1,6-hexanediol-P2) is an effective activator that causes the enzyme to have a higher apparent affinity for ATP- and ADP-glucose than when fructose-1,6-P2 is the activator [14].
• Pyridoxal-P has been shown to be an activator of the spinach leaf ADP-glucose pyrophosphorylase [15].
• ADP-glucose pyrophosphorylase from potato tuber: site-directed mutagenesis of homologous aspartic acid residues in the small and large subunits [16].
• (i) The transformed tubers contained increased activities of several enzymes required for sucrose-starch interconversions including two- to three-fold more sucrose synthase and 60% more ADP-glucose pyrophosphorylase [17].

Other interactions of glgC

• Asp142 in the homotetrameric ADP-glucose pyrophosphorylase (ADP-Glc PPase) enzyme from Escherichia coli was demonstrated to be involved in catalysis of this enzyme [Frueauf, J.B., Ballicora, M.A. and Preiss J. (2001) J. Biol. Chem., 276, 46319-46325] [16].
• The results show that the potato tuber enzyme is homologous to UDP-glucose pyrophosphorylase from slime mold, but not to ADP-glucose pyrophosphorylase from Escherichia coli, and provide structural evidence that UDP-glucose and ADP-glucose pyrophosphorylase are two different protein entities [18].

Analytical, diagnostic and therapeutic context of glgC

• Directed molecular evolution of ADP-glucose pyrophosphorylase [19].
• Site-directed mutagenesis was used to explore the role of Lys-195 in ADP-glucose pyrophosphorylase from Escherichia coli [7].
• Crystallization and preliminary diffraction data of Escherichia coli ADP glucose pyrophosphorylase [10].
• Molecular cloning and expression of the gene encoding ADP-glucose pyrophosphorylase from the cyanobacterium Anabaena sp. strain PCC 7120 [20].

References