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The phosphoryl group on PEP is eventually transferred to the imported sugar via several proteins. The phosphoryl group is transferred to the Enzyme E I (EI), Histidine Protein (HPr, Heat-stable Protein) and Enzyme E II (EII) to a conserved histidine residue, whereas in the Enzyme E II B (EIIB) the phosphoryl group is usually transferred to a cysteine residue and rarely to a histidine.
Transphosphorylation is a chemical reaction in which a phosphate group or a phosphono group is transferred between a substrate and a receptor. [1] There are various phosphate esters in living body including nucleic acid, and phosphorylation reaction related to their synthesis and interconversion is the basis of biochemical reaction.
In biochemistry, a kinase (/ ˈ k aɪ n eɪ s, ˈ k ɪ n eɪ s,-eɪ z /) [2] is an enzyme that catalyzes the transfer of phosphate groups from high-energy, phosphate-donating molecules to specific substrates. This process is known as phosphorylation, where the high-energy ATP molecule donates a phosphate group to the substrate molecule.
The phosphotransferase system (PTS) is a complex group translocation system present in many bacteria. The PTS transports sugars (such as glucose , mannose , and mannitol ) into the cell. The first step of this reaction is phosphorylation of the substrate via phosphotransferase during transport.
Phosphorylation allows cells to accumulate sugars because the phosphate group prevents the molecules from diffusing back across their transporter. Phosphorylation of glucose is a key reaction in sugar metabolism. The chemical equation for the conversion of D-glucose to D-glucose-6-phosphate in the first step of glycolysis is given by:
Phosphoglucomutase (EC 5.4.2.2) is an enzyme that transfers a phosphate group on an α-D-glucose monomer from the 1 to the 6 position in the forward direction or the 6 to the 1 position in the reverse direction. More precisely, it facilitates the interconversion of glucose 1-phosphate and glucose 6-phosphate.
Phosphoglycerate kinase (EC 2.7.2.3) (PGK 1) is an enzyme that catalyzes the reversible transfer of a phosphate group from 1,3-bisphosphoglycerate (1,3-BPG) to ADP producing 3-phosphoglycerate (3-PG) and ATP : 1,3-bisphosphoglycerate + ADP ⇌ glycerate 3-phosphate + ATP. Like all kinases it is a transferase.
The dimers can dimerize as well to form a homotetrameric enzyme. A double phosphoryl transfer mechanism was proposed on the basis of this study: this would involve breakage of PEP's phosphorus-oxygen bond to form a phosphoenzyme intermediate, followed by transfer of the phosphoryl group from the enzyme to carbon-3, forming PPR.