MASS-SPECTROMETRIC STUDIES OF HELMINTHS: INFORMATION TECHNOLOGIES FOR IDENTIFICATION OF PARASITIC INFECTION CAUSES

Abstract

Mass spectrometry is currently used to identify bacteria, mycobacteria and some fungi. Unlike clinical bacteriology, MALDI-TOF MS is practically not used for the identification of human and animal parasites. Homogenate protein profiles were obtained using Microflex LT MALDI-TOF MS (Bruker Daltonics Germany) with Flex Control software, visualized using Flex analysis 3.3 software (Bruker Daltonics). Analysis of protein extracts of nematodes showed spectra with high intensity peaks in the range of 2–20 kDa. Slight differences in the mass spectrometric spectra of Ascaris lumbricoides and Ascaris suum in the same range, which characterizes nematode species, confirm the results obtained in full-genome analysis of helminth data that the causative agent of human ascariasis is an evolutionarily close relative of swine ascarids. In the high ranges of mass spectrometric analysis of Dirofilaria immitis and Dirofilaria repens, significantly frequent peaks were observed, which probably characterize the whole genus of nematodes. In the range above 6000 kDa, the spectra differed in representative peaks, which allowed to differentiate one species from another in protein profile. A comparative analysis of the mass spectrometric peaks of helminths D.repens, D. immitis using R medium (MALDIquant). On the cluster of dendrograms of averaged mass spectra, it was found that for two individuals of D. repens, as well as for two individuals of D. immitis, the sections of the dendrograms coincide with a high degree of probability. For D. immitis, the coincidence rate was 100%, for D. repens 70%. The results obtained can form the basis for the creation of a library of protein profiles with the aim of accelerated and objective dirofilaria differentiation.