Team:HKUST/Back4

The binary toxin BinA and BinB, which is produced in ''Bacillus sphaericus'', is a mosquito-larvicidal crystal protein. It has its maximum activity when both components are present in equimolar ratio[1]. It could kill larvae by forming pores once binA binds to and binB inserts to membrane lipid bilayer, leading to swelling and lysis of the cell[2].

Attempts have been made to produce the binary toxin at a high level in many organisms including ''Escherichia coli''[3]. To obtain a high expression level and a high-potency toxin, one approach is to improve solubility by tagging T7 tag [4] or glutathione S-transferase (GST), between which GST seems to work better. Not only does GST increase the protein expression level, it also improves the solubility of these proteins as well[2].

Yeast has also been a good tool for bacterial toxin studies. It can functionally express many bacterial toxins[5]. Since the binary toxin Bin A and Bin B are very specific to insects, we propose that yeast can express this toxin without damaging itself; at the same time, insects will be killed by the toxin if they eat the yeast. This is why we choose this binary toxin as our “insect killer”.

Background

Experimental Design

Parts Design

Future Work

References