Part:BBa_K1019004
YdeH Diguanylate Cyclase
YdeH is a diguanylate cyclase that is involved in producing the key secondary messenger c-di-GMP. c-di-GMP is proposed to be a "master regulator" of biofilm formation.
Its expression increases surface adhesion and various aspects of the biofilm response.
For further details and additional references please visit [http://ecocyc.org/ECOLI/NEW-IMAGE?type=GENE&object=EG11643 EcoCyc]
Usage and Biology
This part is originated from Pseudomonas aeruginosa. In our project we used this Wspr to test biofilm quantification in order to see what diguanylate cyclase is more efficient in biofilm formation. We use this and others diguanylate cyclases (Yddv and YdeH) in pETSUMO plasmid to run the tests. We did experiments with and without agitation, and also testing the efficiency of biofilm adherence in coconut fiber.
Characterization
By Team iGEM19_USP_SaoCarlos-Brazil 2019
We use this and others diguanylate cyclases (Wspr, YddV) in pETSUMO plasmid to run the test. We did experiment with and without agitation, and also testing the efficiency of biofilm in coconut fiber. The quantification was made by optical absorption measurement of Crystal violet. To know the specific protocol we used, access https://2019.igem.org/Team:USP_SaoCarlos-Brazil/Experiments.
As it can be seen from figure 1, the bacteria transformed with YdeH showed a higher biofilm production in a non-static condition. This DGC did not produce significant amounts of biofilm, even though we can see a small increase in the absorption bar when under agitation. It’s interesting to note that a certain quantity of biofilm was expected for the control, pETSUMO without DGC insert, since our bacteria naturally produces low rates of biofilm.
The 48h static plate showed lower biofilm formation if compared to the 24h static plate. This could indicate a natural tendency for the E. coli to not maintain the small amount of biofilm that they produced under static conditions, since forming this matrix it’s a costly metabolic function.
As for the 48h agitated plate, the absorption rate changed significantly for the bacteria transformed with YdeH, and showed the biggest change in the absorption rate from 24 hours to 48 hours, indicating a preference for a longer period of incubation under agitated conditions.
The agitated YdeH showed a very heterogeneous growth, so we can infer that this is a form of response from this DGC and that these bacterias would reach a higher level of absorbance if a longer incubation time was tested.
The same results can be presented in a different manner, In order to evaluate the changes happening from 24h to 48h, we plotted the change in absorption against time:
In the end of our experiments, we came to the conclusion that YdeH is very efficient in biofilm production when incubated for a minimum of 48h in agitation.
In order to test our project in a large scale, we tried to grow and quantify biofilm in coconut fiber.
Comparing with previous experiments, there is a possibly of biofilm adhesion on coconut fiber given it’s decreased stained in the plate reading. We measured absorbance of crystal violet in both components: fiber and plate, to confirmate the distribution of biofilm growth. Our plan was use LB broth as a normalization of the experiment but after measures we realized that could possibly occurred a saturation on absorbance value that didn’t surpassed 3.3.
We obtained a similar result for 72 hours well plate for the fibers and an increase of growth in the plate compared with 48 hours. Limit of absorbance remained the same, reinforcing the idea of a saturated solution of crystal violet, preventing our initial comparison plan. So with this experiment we tried to measure the concentration of biofilm with coconut fiber. But we noticed that our results had a methodological problem because although we realized that there was a biofilm, with 48h and 72h of growth we reached the acid acetic and violet crystal saturation and we couldn’t conclude how much biofilm grown up adhered.
References
Escherichia coli K-12 substr. MG1655 Enzyme: diguanylate cyclase. (2013). Ecocyc. Retrieved May 20, 2013, from http://ecocyc.org/ECOLI/NEW-IMAGE?type=GENE&object=EG11643
Ha DG, O'Toole GA. c-di-GMP and its Effects on Biofilm Formation and Dispersion: a Pseudomonas Aeruginosa Review. Microbiol Spectr. 2015;3(2):10.1128/microbiolspec.MB-0003-2014. doi:10.1128/microbiolspec.MB-0003-2014
Valentini M, Filloux A. Biofilms and Cyclic di-GMP (c-di-GMP) Signaling: Lessons from Pseudomonas aeruginosa and Other Bacteria. J Biol Chem. 2016;291(24):12547–12555. doi:10.1074/jbc.R115.711507
Sequence and Features
- 10COMPATIBLE WITH RFC[10]
- 12COMPATIBLE WITH RFC[12]
- 21COMPATIBLE WITH RFC[21]
- 23COMPATIBLE WITH RFC[23]
- 25COMPATIBLE WITH RFC[25]
- 1000INCOMPATIBLE WITH RFC[1000]Illegal SapI.rc site found at 775
Illegal SapI.rc site found at 800
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