Original Research ARTICLE
Hydrodynamics enhances colonization of sinking nutrient sources by motile microorganisms
- 1Purdue University, United States
In this study, we document hydrodynamics-mediated trapping of microorganisms around a moving spherical nutrient source such as a settling marine snow aggregate. There exists a range of size and excess density of the nutrient source, and motility and morphology of the microorganism under which hydrodynamic interactions enable the passive capture of approaching microorganisms onto a moving nutrient source. We simulate trajectories of chemotactic and non-chemotactic bacteria encountering a sinking marine snow particle effusing soluble nutrients. We calculate the average nutrient concentration to which the bacteria are exposed, under regimes of strong and weak hydrodynamic trapping. We find that hydrodynamic trapping can significantly amplify (by ~ 40%) the nutrient exposure of bacteria, both chemotactic and non-chemotactic. The subtle interactions between hydrodynamic and chemotactic effects reveal non-trivial variations in this `hydrodynamic amplification', as a function of relevant biophysical parameters. Our study provides a consistent description of how microorganism motility, fluid flow and nutrient distribution affect foraging by marine microbes, and the formation of biofilms on spherical nutrient sources under the influence of fluid flow.
Keywords: Marine snow particles, Hydrodynamic interactions, Chemotaxis, marine bacteria, Phytoplakton
Received: 01 Oct 2018;
Accepted: 04 Feb 2019.
Edited by:Albert Siryaporn, University of California, Irvine, United States
Reviewed by:Rachel Bearon, University of Liverpool, United Kingdom
Steve Presse, School of Life Sciences, Arizona State University, United States
Copyright: © 2019 Desai, Shaik and Ardekani. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Dr. Arezoo M. Ardekani, Purdue University, West Lafayette, United States, email@example.com