Team:Wageningen UR/Demonstrate

Wageningen UR iGEM 2016




Our project does not have a finished product that is ready to be deployed in the field. However, we felt that we have accomplished a great many parts of our project and we want to show you what we did.

Sensing Varroa in Infected Beehives

We demonstrated the functionality of the mite-sensing system in beehives. We cannot demonstrate the BeeT product in the field, as this would break the do not release requirement. We also cannot keep a beehive in the lab, for obvious reasons. We tested the guanine and vitamin B12 riboswitches on crushed up hive fragments (Figure 1).

Figure 1. Fluorescence data for guanine (a) and vitamin B12 (b) riboswitch constructs with inverter and mRFP reporter. We show three replicates for two different samples from a contaminated beehive. For the beehive 2 sample we are sure that this part of the hive was infested with Varroa, for the beehive 1 sample we cannot be sure whether it has been in contact with Varroa mites.

From Figure 1 becomes apparent that the beehive samples cause a different mRFP response on both mite sensing systems. Initially, the mRFP amount is increases more rapidly in samples containing beehive fragments. This suggests that the constructs are indeed able to sense and report guanine and vitamin B12 in contaminated beehives.

BeeT Survival in Beehive Conditions

We simulated the sugar water conditions, BeeT would encounter when applied, in the lab to check for survival. This is shown in Figure 2.

Figure 2. The relationship between the maximum ATP available for survival for an E. coli in a sugar-water environment and the theoretical survival time, given a constant water efflux over this time and a starting volume of 2.8e-13 grams. The various coloured lines indicate water tolerance thresholds for the E. coli

Effectiveness of BeeT on Beecolonies

Additionally, we modeled the impact of BeeT on bee and mite dynamics under real world weather conditions. We show this in figure 3.

Figure 3. The honey bee population is shown in blue and the Varroa mite population in red. A: Colony rapidly declines when no BeeT is present. Starting population is 20 Varroa B: Colony barely survives Varroa mite infestation. Shows Varroa mite in red and worker bee population in blue. Starting population is 20 Varroa. C: Colony thrives regardless of Varroa mite infestation. Starting population is 20 Varroa mites. D: Colony thrives regardless of heavy Varroa mite infestation. Starting population is 10,000 Varroa mites.

We asked design student Thieu Custers, from the Design Academy Eindhoven, to develop a visual prototype. Below you can find his design and explanation.

See our design page.