Title: Studying taxis in real time using optical tweezers: applications for Leishmania amazonensis parasites.
Author: Pozzo, L. Y.; Fontes, A.; Thomas, A. A.; Ayres Dc; Albuquerque, S.; Giorgio, S.; Cesar Cl
Is part of: Micron (Oxford. 1993), v. 40, p. 617 - 620
Citation: Pozzo, L. Y.; Fontes, A.; Thomas, A. A.; Ayres Dc; Albuquerque, S.; Giorgio, S.; Cesar Cl; Studying taxis in real time using optical tweezers: applications for Leishmania amazonensis parasites.. Micron (Oxford. 1993), v.40, p. 617-620, 2009
Abstract: Beads trapped by an optical tweezers can be used as a force transducer for measuring forces of the same order of magnitude as typical forces induced by flagellar motion. We used an optical tweezers to study chemotaxis by observing the force response of a flagellated microorganism when placed in a gradient of attractive chemical substances. This report shows such observations for Leishmania amazonensis, responsible for leishmaniasis, a serious disease. We quantified the movement of this protozoan for different gradients of glucose. We were able to observe both the strength and the directionality of the force. The characterization of the chemotaxis of these parasites can help to understand the mechanics of infection and improve the treatments employed for this disease. This methodology can be used to quantitatively study the taxis of any kind of flagellated microorganisms under concentration gradients of different chemical substances, or even other types of variable gradients such as temperature and pressure. (C) 2009 Elsevier Ltd. All rights reserved.
Funding: The authors are grateful to CAPES, CNPq, FAPESP, Loreal, Brazilian Academy of Sciences and UNESCO. This work is also linked with the CEPOF (Optics and Photonics Research Center, FAPESP) and National Institute of Photonics Applied to Cell Biology.