Difference between revisions of "Part:BBa K1807001"

Revision as of 23:25, 18 September 2015

Escherichia coli Exopolyphosphatase (PPX)

This part codes for the exopolyphosphatase (PPX) enzyme of Escherichia coli. PPX is able to release phosphate residues from the ends of a polyphosphate chain.

Usage and Biology

Exopolyphosphatase is an enzyme encoded by the PPX gene (Akiyama et al., 1993). Exopolyphosphatase cleaves phosphate residues from the termini of polyphosphate chains. Preferred substrate seems to be polyphosphate with approximately 500 residues long chain. ATP and short polyphosphate chains (around 15 residues) are either not a substrate at all or compete poorly with long polyphosphate.

Akiyama, M., E. Crooke, and A. Kornberg. "An exopolyphosphatase of Escherichia coli. The enzyme and its ppx gene in a polyphosphate operon." Journal of Biological Chemistry 268.1 (1993): 633-639.

iGEM York 2015 designed this protein generator part in order to test exopolyphosphatase's effect on phosphate uptake and storage of polyphosphate. This testing construct was based on the observations made in Keasling et al., 1998.

Keasling, J. D., Stephen J. Van Dien, and Jaya Pramanik. "Engineering polyphosphate metabolism in Escherichia coli: implications for bioremediation of inorganic contaminants." Biotechnology and bioengineering 58.2‐3 (1998): 231-239.

Sequence and Features