Glossina (G.) spp. (Diptera: Glossinidae), known as tsetse flies, are vectors
of African trypanosomes that cause sleeping sickness in humans and nagana in
domestic livestock. Knowledge on tsetse distribution and accurate species
identification help identify potential vector intervention sites.
Morphological species identification of tsetse is challenging and sometimes
not accurate. The matrix-assisted laser desorption/ionisation time of flight
mass spectrometry (MALDI TOF MS) technique, already standardised for microbial
identification, could become a standard method for tsetse fly diagnostics.
Therefore, a unique spectra reference database was created for five lab-reared
species of riverine-, savannah- and forest- type tsetse flies and incorporated
with the commercial Biotyper 3.0 database. The standard formic
acid/acetonitrile extraction of male and female whole insects and their body
parts (head, thorax, abdomen, wings and legs) was used to obtain the flies'
proteins. The computed composite correlation index and cluster analysis
revealed the suitability of any tsetse body part for a rapid taxonomical
identification. Phyloproteomic analysis revealed that the peak patterns of G.
brevipalpis differed greatly from the other tsetse. This outcome was
comparable to previous theories that they might be considered as a sister
group to other tsetse spp. Freshly extracted samples were found to be matched
at the species level. However, sex differentiation proved to be less reliable.
Similarly processed samples of the common house fly Musca domestica (Diptera:
Muscidae; strain: Lei) did not yield any match with the tsetse reference
database. The inclusion of additional strains of morphologically defined wild
caught flies of known origin and the availability of large-scale mass
spectrometry data could facilitate rapid tsetse species identification in the
futur
