Transient superdiffusion and long-range correlations in the motility patterns of trypanosomatid flagellate protozoa

TL;DR

This study analyzes the motility of pathogenic protozoa, revealing transient superdiffusive behavior, self-similar radial position distributions, and long-range velocity correlations, suggesting universal movement mechanisms that could aid drug activity assessment.

Contribution

It uncovers universal superdiffusive motion patterns and long-range correlations in protozoan motility, providing new insights into their movement mechanisms and potential drug testing tools.

Findings

Protozoa exhibit transient superdiffusive motion.

Radial positions follow a stretched Gaussian distribution.

Velocity series show long-range correlations with high Hurst exponents.

Abstract

We report on a diffusive analysis of the motion of flagellate protozoa species. These parasites are the etiological agents of neglected tropical diseases: leishmaniasis caused by Leishmania amazonensis and Leishmania braziliensis, African sleeping sickness caused by Trypanosoma brucei, and Chagas disease caused by Trypanosoma cruzi. By tracking the positions of these parasites and evaluating the variance related to the radial positions, we find that their motions are characterized by a short-time transient superdiffusive behavior. Also, the probability distributions of the radial positions are self-similar and can be approximated by a stretched Gaussian distribution. We further investigate the probability distributions of the radial velocities of individual trajectories. Among several candidates, we find that the generalized gamma distribution shows a good agreement with these distributions. The velocity time series have long-range correlations, displaying a strong persistent behavior (Hurst exponents close to one). The prevalence of "universal" patterns across all analyzed species indicates that similar mechanisms may be ruling the motion of these parasites, despite their differences in morphological traits. In addition, further analysis of these patterns could become a useful tool for investigating the activity of new candidate drugs against these and others neglected tropical diseases.