Uptake hexose phosphate

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

The Uptake of Hexose Phosphates (Uhp) is a protein system found in bacteria. It is a type of two-component sensory transduction pathway which helps bacteria react to their environment.[1]

Protein Components[edit]

The uhp system is composed of UhpA, UhpB, UhpC, and UhpT. UhpB and UhpC are both transmembrane proteins which form a complex with each other. UhpA is a signal protein found in the cytoplasm.[2] UhpT is a transporter protein which facilitates the uptake of phosphorylated hexose molecules into the cell.[3]

Functionality[edit]

The Uhp system uptakes phosphorylated hexose sugars into bacteria. The system is triggered by phosphorylated hexose sugars on the outside of the cell. UhpC binds to the phosphorylated hexose, which allows the phosphorylation of UhpB on one of its cytoplasmic histadines. This facilitates the phosphorylation of an aspartate on UhpA,[2] and the phosphorylated UhpA activates the transcription of UhpT.[2] UhpT then facilitates the transport of the phosphorylated hexose sugars into the cell.[3]

References[edit]

  1. ^ Shattuck-Eidens, Donna M.; Kadner, Robert J. (1981). "Exogenous Induction of the Escherichia coli Hexose Phosphate Transport System Defined by uhp-lac Operon Fusions". Journal of Bacteriology. 148 (1): 203–9. PMC 216182. PMID 6793554.
  2. ^ a b c Shattuck-Eidens, Donna M.; Kadner, Robert J. (1983). "Molecular Cloning of the uhp Region and Evidence for a Positive Activator for Expression of the Hexose Phosphate Transport System of Escherichia coli". Journal of Bacteriology. 155 (3): 1062–70. PMC 217799. PMID 6350260.
  3. ^ a b Hoffer, Sally; Uden, Nathalie; Tommassen, Jan (2001). "Expression of the pho regulon interferes with induction of the uhpT gene in Escherichia coli K-12". Archives of Microbiology. 176 (5): 370–6. doi:10.1007/s002030100339. PMID 11702079.