Team:ITB Indonesia/Results
Results
Results
Experiments to test our project were segmented into three different sections:
PETase Activity Assay, pSal Inducibility Assay, Biofilm Formation Assay
1. PETase Activity Assay
The goal of this assay is to determine and measure the PET-degrading abilities of our parts. The first experiment is carried out using pNPB Assay. PETase activity was tested using pNPB (p-nitrophenyl butyrate) Assay which measures esterase activity. Trasformants of BBa_K2378005 were grown for 4, 16, 24 hours in LB and tested against pNPB to determine their esterase activities, which were measured spectrophotometrically. As controls, we grew BL21 cells without plasmid with the same variations of age.
The results clearly showed that PETase activities were observed in all different variations of bacterial age, as the absorbance differences with their individual controls were significant. We can thus conclude that this part works as intended.
The difference of PETase activity among the 3 varying culture ages were not significant. One major observation point is that in culture grown for only 4 hours, the initial activities were lower. This might be due to the that the initial concentration of available PETase was lower as well.
Aside from that, we also tested PETase activity by directly applying our PET-degrading bacteria into PET bottle fragments. After 2 days of incubation, the fragments were visualized using Scanning Electron Microscope (SEM) techniques.
The results showed that the surface of PET fragments inoculated by PETase-containing cultures are rougher and have more cracks. This is most likely due to the activity of PETase.
