Team:NYMU-Taipei/Project/Phosphate

From 2008.igem.org

(Difference between revisions)
(Phosphate removal by Microbe)
(Goal)
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* Enhance and regulate the phosphate absorption of ''E.coli'' to balance phosphate concentration to a normal level in patients with kidney failure.
* Enhance and regulate the phosphate absorption of ''E.coli'' to balance phosphate concentration to a normal level in patients with kidney failure.
* This device operates when:
* This device operates when:
-
** external pH is high.
+
** external pH is high and
-
** external phosphate level is high.
+
** external phosphate level is high
 +
* This device stops when
 +
** external pH is low or
 +
** external phosphate level is low
== Circuit Design ==
== Circuit Design ==

Revision as of 08:10, 3 August 2008

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Contents

Motivation

  • When the phosphate level in blood exceeds 6.5 mg/dl, a patient kidney failure has a high risk of death.
  • A high serum concentration of [http://en.wikipedia.org/wiki/Phosphate phosphate (pi)] is clearly related to pruritus (搔癢症) and hyperparathyroidism (甲狀旁腺功能亢進症), both manifestations of the uremic syndrome.
  • Phosphorus excess also inhibits 1 alpha-hydroxylase and hence the production of [http://www.nlm.nih.gov/medlineplus/druginfo/medmaster/a682335.html calcitriol], the active vitamin D metabolite.
  • Phosphorus retention also alters polyamine metabolism by causing decreases in intestinal function and proliferation of intestinal villi.

Goal

  • Enhance and regulate the phosphate absorption of E.coli to balance phosphate concentration to a normal level in patients with kidney failure.
  • This device operates when:
    • external pH is high and
    • external phosphate level is high
  • This device stops when
    • external pH is low or
    • external phosphate level is low

Circuit Design

NYMU iGEM08 phosphate removal device v 1.0

NYMU IGEM08 phosphate device.png

  • over-expression of pst operon can enhance the total phosphate absorption by improving the cellular phosphate import
  • over-expression of ppK gene can enhance the total phosphate absorption by improving the cellular phosphate storage

References

Phosphate Metabolism and Regulation in E.coli

  • [http://jb.asm.org/cgi/content/abstract/183/17/5008 Characterization of PitA and PitB from Escherichia coli, JB 2001]
  • [http://aem.asm.org/cgi/content/full/68/8/4107?view=long&pmid=12147514 Accumulation of Inorganic Polyphosphate in phoU Mutants of Escherichia coli and Synechocystis sp. Strain PCC6803, AEM 2002]
  • [http://www.blackwell-synergy.com/doi/abs/10.1111/j.1574-6976.2008.00101.x The phosphate regulon and bacterial virulence: a regulatory network connecting phosphate homeostasis and pathogenesis, FEMS Microbiology Reviews 2008]

Phosphate removal by Microbe

  • [http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=182526 Genetic improvement of Escherichia coli for enhanced biological removal of phosphate from wastewater, AEM 1993]
  • [http://www.ncbi.nlm.nih.gov/pubmed/10448683 Genetic improvement of bacteria for enhanced biological removal of phosphate from wastewater, Prog Mol Subcell Biol. 1999]
  • [http://www.ncbi.nlm.nih.gov/pubmed/12964240 Microbial phosphate removal and polyphosphate production from wastewaters, Adv Appl Microbiol. 2003]
  • [http://www.ncbi.nlm.nih.gov/pubmed/12187377 Enhanced phosphate uptake and polyphosphate accumulation in Burkholderia cepacia grown under low pH conditions, Microb Ecol. 2002]
  • [http://www.springerlink.com/content/t6qkt5214pqncmjd/ Intelligent yeast strains with the ability to self-monitor the concentrations of intra- and extracellular phosphate or ammonium ion by emission of fluorescence from the cell surface, AMB 2004]
  • [http://www.jstage.jst.go.jp/article/jbb/95/6/95_637/_article/-char/en A method for screening polyphosphate-accumulating mutants which remove phosphate efficiently from synthetic wastewater, Journal of Bioscience and Bioengineering 2005]