Substrate Set

Our substrate screening experiment produced a large number of interesting substrates for our detection assay. We looked at the raw fluorescence measurements, but we also applied statistical analysis to identify the peptides that had significant differences between the three venoms. In addition, we modelled the enzymatic activity of the venoms based on our measurements.

Venn Diagram — Figure 1: Significant substrates found in our experiment, by looking at the signal difference between the three snakes after the 60 minutes timepoint. BA represents *Bitis arietans*, BG represents *Bitis gabonica* and NN *Naja nigricollis*. Significance here is defined by log10(p) < -9.

You can find the plots of logarithmic fluorescence signal and time of all the substrates here

The relative signal of each substrate between the three snakes was also analyzed. You can find that part here

Lastly, we looked at the fluorescence output in terms of enzymatic activity. We fit a non-linear model in the reactions and calculated their rates. You can find the models for all the substrates here

J12_MR — Figure 2a, 2b, 2c, 2d: Non-linear model fitted in fluorescence measurements. The sequences of the peptides can be seen next to their well numbers. J12 is cleaved by all three venoms, N21 by *Bitis gabonica* and *Bitis arietans*, B17 only by *Bitis arietans*, and O22 only by *Bitis gabonica*. Background noise has been deducted from the measurements.

N21_MR — Figure 2a, 2b, 2c, 2d: Non-linear model fitted in fluorescence measurements. The sequences of the peptides can be seen next to their well numbers. J12 is cleaved by all three venoms, N21 by *Bitis gabonica* and *Bitis arietans*, B17 only by *Bitis arietans*, and O22 only by *Bitis gabonica*. Background noise has been deducted from the measurements.

Histogram — Figure 3: Occurrences of enzymatic rates of the models for each snake venom.

LacZ Device

Purpose

If β-galactosidase is used as a reporter in our biosensor, we would have an output of our device that depends on two subsequent enzymatic reactions. We want to model how the enzymatic activity of the first reaction affects the kinetics of the secondary reaction, and find some optimal time for the first reaction to run, if we want the combined time of both enzymatic reactions to be as short as possible.

Background

In investigating if our prototype would be a viable option for in-field detection we decided to meet with Andreas Lausten, Co-founder of VenomAB, a producer of breakthrough solutions to modern antivenom monovalent production . As per his recommendation our system would ideally have to give a rapid response. As of yet, our assays had shown response time above 45 minutes for certain venoms, and we should seek to reduce the response time. In doing this we would have to amplify the output of our device compared to that of just using chromoproteins such as AmilCP.

Team:DTU-Denmark/Model

Substrate Set

LacZ Device

Purpose

Background

Central assumptions