Team:Edinburgh/Experiments

malS test systems

Since constructing a cellulose-degrading system would involve three enzymes, a simpler system involving starch degradation by an amylase enzyme (the malS gene of E. coli) is being attempted.

4 August: malS starch degradation assay

Starch turns black in the presence of iodine, so we can do a qualitative test for starch degradation by flooding a starch agar plate with iodine. If starch degradation is occurring, we would expect to see a zone of clearing around the bacterial colonies.

Colonies with the malS gene under the control of the lac promoter (i.e. <partinfo>BBa_K523006</partinfo> we hope; awaiting sequencing) did not show starch degradation. This is sort of expected. The malS amylase is periplasmic and so is not expected to actually degrade starch until we get it fused to INP so that it is present on the outside of the cell.

Fixme: this should be redone with proper controls.