Purdue/7 July 2008

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Death of the lycopene gene
Was in contact with Dr. Chris French from the University of Edinburgh over the weekend about their BioBrick part that encoded the lycopene producing gene. Dr. French stated that the part worked only marginally and that it took a long time to produce the faint pink color they recorded. Upon further contact with Dr. French, the team decided that going another route would be more beneficial to our cause in the immediate future. Further information about the carotenoid producing genes will be very useful in latter production of our UV bio-sensor.

A new search was undertaken by Janie and Craig to find a new color responder. Briefly, luciferase was considered, but then neglected when the availability of luciferin was found. Craig remembered his Microbiology class and the fact that certain differential medias selected bacteria on the basis of metabolic activity. MacConkey agar will turn pink as a result of a pH drop when lactose is metabolized into lactic acid.

Upon further investigation into the genotype of the competent cells we have been using, we found them to be lac- but still containing the lacZ omega fragment. Therefore, we have decided to attempt a construct containing the lacZ alpha fragment and the lacY gene, transformed in behind the phr promoter that when activated will form pink colonies on the MacConkey agar. The SOS response will remain the same with X-gal and the blue producing color. Part numbers (I732018 (LacZ alpha), I763015 (LacY), I732017 (LacZ full), J22106 (SOS)) will be incorporated to test this theory.

Edited by Craig Barcus and Janie Stine

Shipment of DNA
Katie Clifford has proved instrumental in obtaining more SOS and lacZ DNA after our failed attempts at transforming ourselves. Further research into the problems of our transformations will be taking place in the near future. Tubes innoculated with glycerol stocks of the library cells were shipped out today and should arrive either tomorrow or the next day.

Edited by Craig Barcus