Team:Newcastle/Swarming
From 2010.igem.org
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Swarming
It is known that Bacillus subtilis (strain 168) which is generally used in the lab is unable to swarm on a solid surface eg. agar plate. This is because of two reasons which are:
- Surfactin is a natural surfactant which helps in reducing surface tension and aids the bacteria to swarm on a solid or semi solid medium. Strain 168 is unable to produce the bacterial cyclic lipopeptide surfactin.
- Strain 168 is also unable to bio synthesize flagellum and thus has a very low amount of swarming.
sfp
Strain 168 is unable to produce surfactin because it contains a frameshift mutation in the gene named sfp. In a non domisticated strain 3610, sfp gene is intact and thus produces a protein which helps in the post translational modification of the immature surfactin peptide formed by the srfABCD operon. After the modification, this peptide is exported out of the cell and helps in breaking the surface tension and aids the movement of the bacteria.
swrA
In the undomesticated strain 3610, the gene swrA along with the gene swrB helps in the bio synthesis of flagellum. swrA acts on the the gene sigD which acts a transcription for the genes required in the late flagellum biosynthesis. The laboratory strain 168 contains a fameshift mutation in the gene swrA and thus the stain moves on the surface with a very slow pace.
swrC
It provides resistance to the antimicrobial action of the peptide surfactin.
efp
efp stands for Elongation Factor P and this gene helps in the non dendritic swarming.