Difference between revisions of "Part:BBa K1675000"

Revision as of 20:10, 18 September 2015

NhaA; sodion-proton antiporter; membrane protein

Nha is a family containing a number of bacterial sodium-proton anti-porters. These are integral membrane proteins that catalyze the exchange of protons for sodiums in a manner highly dependent on the pH. To resist different pH, we selected two genes, NhaA and NhaB, from this family. NhaA is the archetypal sodium/proton anti-porter and the only member of the family that is required by E.coli for survival under alkaline stress. It is a membrane protein consisting of 388 residues. NhaA excretes sodiums from the cytoplasm using the energy from the cotransport of protons down their electrochemical gradient into the cell, with a characteristic electrogenic stoichiometry of two protons to one sodium (Fig.1). Like many other sodium/proton anti-porters, NhaA is regulated by pH. It is essentially inactive below pH 7, and the sodium efflux rate increases by three orders of magnitude between pH 6.5 and 8.5.

Sequence and Features

Assembly Compatibility:

10
COMPATIBLE WITH RFC[10]
12
INCOMPATIBLE WITH RFC[12]
Illegal NheI site found at 261
21
INCOMPATIBLE WITH RFC[21]
Illegal BglII site found at 458
Illegal BamHI site found at 995
23
COMPATIBLE WITH RFC[23]
25
INCOMPATIBLE WITH RFC[25]
Illegal NgoMIV site found at 321
1000
COMPATIBLE WITH RFC[1000]

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 <partinfo>BBa_K1675000 short</partinfo>
-The gene, ''NhaA'', is the archetypal sodium/proton anti-porter in ''E. coli''. It is the only member of the family that is absolutely required by ''E. coli'' for survival in high-salt conditions, under alkaline stress, or in the presence of otherwise toxic Lithium-ion concentration.
+''Nha'' is a family containing a number of bacterial sodium-proton anti-porters. These are integral membrane proteins that catalyze the exchange of protons for sodiums in a manner highly dependent on the pH. To resist different pH, we selected two genes, ''NhaA'' and ''NhaB'', from this family.
-''NhaA'' catalyzes the exchange of 2 protons per soduim ion. The anti-porter active at alkaline pH, whose activity is strongly down-regulated below pH 6.5. Therefore, ''NhaA'' could make sure ''E. coli''’s survival under alkaline pH, which are in desperate need in our project.
+''NhaA'' is the archetypal sodium/proton anti-porter and the only member of the family that is required by ''E.coli'' for survival under alkaline stress. It is a membrane protein consisting of 388 residues. ''NhaA'' excretes sodiums from the cytoplasm using the energy from the cotransport of protons down their electrochemical gradient into the cell, with a characteristic electrogenic stoichiometry of two protons to one sodium (Fig.1). Like many other sodium/proton anti-porters, ''NhaA'' is regulated by pH. It is essentially inactive below pH 7, and the sodium efflux rate increases by three orders of magnitude between pH 6.5 and 8.5.
+[[File:BIT_China_Resistance_System_pic1.png]]