Team:Cambridge/Bioluminescence/Bacterial Codon optimisation

From 2010.igem.org

(Difference between revisions)
(What is codon usage?)
Line 10: Line 10:
=Altered G-C content=
=Altered G-C content=
DNA curvature is increased by sequences rich in A-T or G-C pairs. The natural ''V.fischeri'' Lux operon, and especially its intergenic regions, contains stretches rich in A-T, resulting in the curvature that H-NS proteins bind to preferentially. Changing the coding DNA sequence also meant changing the curvature of the DNA, which affects the binding affinity of H-NS proteins. To alleviate the repression that H-NS exerts, we took care to raise the G-C content of intergenic regions and coding sequences (at times resorting to suboptimal codons). According to a computational prediction, this resulted in greatly reduced DNA curvature, and thus hopefully to a reduced affinity for H-NS proteins.
DNA curvature is increased by sequences rich in A-T or G-C pairs. The natural ''V.fischeri'' Lux operon, and especially its intergenic regions, contains stretches rich in A-T, resulting in the curvature that H-NS proteins bind to preferentially. Changing the coding DNA sequence also meant changing the curvature of the DNA, which affects the binding affinity of H-NS proteins. To alleviate the repression that H-NS exerts, we took care to raise the G-C content of intergenic regions and coding sequences (at times resorting to suboptimal codons). According to a computational prediction, this resulted in greatly reduced DNA curvature, and thus hopefully to a reduced affinity for H-NS proteins.
 +
 +
[[Image:Example.jpg|600px|center| The LuxC coding region before and after codon optimisation. Blue denotes A-T rich regions. Note the reduction in A-T rich stretches after opitmisation]]
=Differential Expression=
=Differential Expression=

Revision as of 00:57, 26 October 2010