Versicolysin A (VerA) is an aegerolysin protein produced by basidiomycetes Trametes versicolor. This mushroom also produces a partner protein versicolysin B (VerB) with membrane attack complex/perforin (MACPF) domain. The purpose of this thesis was to prepare and express recombinant proteins VerA and VerB, and to characterize their biochemical properties. Recombinant proteins were expressed and produced in bacterium Escherichia coli. We also obtained a VerA deletion mutant (Δ37VerA) without the first 37 amino acids. These amino acids are usually not present in other known aegerolysins. Furthermore, we predicted the 3D structures for all these three proteins. Using the sedimentation test, we showed that VerA is not a stable protein and that it precipitates in solution. On the other hand, we found that Δ37VerA binds to lipid vesicles reconstituted from the insect cell line Sf9 total lipid extract. While the combination of VerA and VerB did not induce hemolysis, the combination of relatively high concentrations of Δ37VerA and VerB did show hemolytic activity and this activity was enhanced in acidic conditions. We also tested VerA/VerB or Δ37VerA/VerB cytolytic activity on the insect cell line Sf9 in vitro and found that these protein combinations are not cytolytic for these cells.
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