Notebook – Results – 4. CULTIVATION E.coli

Autoinduction reagents were added to the medium in each tube. We give certain treatments to the culture medium which are glucose, fructose, glucose + fructose, or honey. For glucose, fructose, and glucose + fructose treatments, the final concentration given for each tube are gradually increases from tube number 1 - 12.

As shown in figure 1, the medium showed the gradual color change from red to yellow. It proves the catabolite repression mechanism is work in our system. The addition of glucose decrease the expression of mRFP gene, more high the amount of glucose presence in the medium more decrease the expression of mRFP gene.

As shown in figure 2, the medium showed the gradual color change from red to yellow. It proves that fructose and glucose exhibit a very similar trend in catabolite repression by repressing the expression of the mRFP gene. The similarity of the fructose and glucose induction patterns might be due to the fact that fructose and glucose both utilize that PTS, leading to low levels of cAMP (Chu et al, 2002).

As shown in figure 3, plasmid Bba_J04450 that has been added by new circuit containing Adenylate cyclase gene shows the changing of color graduation. Dark red color showed by tube number 4, followed by tubes number 5,6, and 7. Tubes number 1,2, and 3 show brighter red color, while the rest of tubes (8-12) show yellow color. Comparing to the result from plasmid BBa_J04450 cultivation, we can conclude that our system works successfully. The system can measure glucose concentration in higher glucose concentration

As shown in figure 4, plasmid BBa_J04450 has been added by new circuit containing IIAglc gene also shows the changing of color graduation. Dark red yellow showed by tube number 4, followed by tubes number 5, 6, and 7. Tubes number 1,2, and 3 show brigther red color, while the rest of tubes (8-12) show yellow color. Comparing to the result from plasmid BBa_J04450 cultivation, we can conclude that our sysem works successfully. The system changed catabolite repression phenomenon.

1.) Natural honey with glucose concentration 133,2 mM 2.) Chinese honey with glucose concentration 242,5 mM 3.) Sunshine honey with glucose concentration 130,06 mM, 4.) Gapit (Sumbawa honey) with glucose concentration 40,8 mM, 5.) Batu dulang (Sumbawa honey) with glucose concentration 43,6 mM, 6.) Sampa honey (Sumbawa honey) with glucose concentration 44,6 mM.

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