Modeling aerotaxis band formation in Azospirillum brasilense
Abstract Background Bacterial chemotaxis, the ability of motile bacteria to navigate gradients of chemicals, plays key roles in the establishment of various plant-microbe associations, including those that benefit plant growth and crop productivity. The motile soil bacterium Azospirillum brasilense...
Main Authors: | , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
BMC
2019-05-01
|
Series: | BMC Microbiology |
Subjects: | |
Online Access: | http://link.springer.com/article/10.1186/s12866-019-1468-9 |
id |
doaj-285b53baef1c4d31a757bd59b09d5c54 |
---|---|
record_format |
Article |
spelling |
doaj-285b53baef1c4d31a757bd59b09d5c542020-11-25T02:26:53ZengBMCBMC Microbiology1471-21802019-05-0119111010.1186/s12866-019-1468-9Modeling aerotaxis band formation in Azospirillum brasilenseMustafa Elmas0Vasilios Alexiades1Lindsey O’Neal2Gladys Alexandre3Mathematics, University of TennesseeMathematics, University of TennesseeBiochemistry and Cellular & Molecular Biology, University of TennesseeBiochemistry and Cellular & Molecular Biology, University of TennesseeAbstract Background Bacterial chemotaxis, the ability of motile bacteria to navigate gradients of chemicals, plays key roles in the establishment of various plant-microbe associations, including those that benefit plant growth and crop productivity. The motile soil bacterium Azospirillum brasilense colonizes the rhizosphere and promotes the growth of diverse plants across a range of environments. Aerotaxis, or the ability to navigate oxygen gradients, is a widespread behavior in bacteria. It is one of the strongest behavioral responses in A. brasilense and it is essential for successful colonization of the root surface. Oxygen is one of the limiting nutrients in the rhizosphere where density and activity of organisms are greatest. The aerotaxis response of A. brasilense is also characterized by high precision with motile cells able to detect narrow regions in a gradient where the oxygen concentration is low enough to support their microaerobic lifestyle and metabolism. Results Here, we present a mathematical model for aerotaxis band formation that captures most critical features of aerotaxis in A. brasilense. Remarkably, this model recapitulates experimental observations of the formation of a stable aerotactic band within 2 minutes of exposure to the air gradient that were not captured in previous modeling efforts. Using experimentally determined parameters, the mathematical model reproduced an aerotactic band at a distance from the meniscus and with a width that matched the experimental observation. Conclusions Including experimentally determined parameter values allowed us to validate a mathematical model for aerotactic band formation in spatial gradients that recapitulates the spatiotemporal stability of the band and its position in the gradient as well as its overall width. This validated model also allowed us to capture the range of oxygen concentrations the bacteria prefer during aerotaxis, and to estimate the effect of parameter values (e.g. oxygen consumption rate), both of which are difficult to obtain in experiments.http://link.springer.com/article/10.1186/s12866-019-1468-9ChemotaxisAerotaxisBand formationAzospirillum brasilenseMathematical modeling |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Mustafa Elmas Vasilios Alexiades Lindsey O’Neal Gladys Alexandre |
spellingShingle |
Mustafa Elmas Vasilios Alexiades Lindsey O’Neal Gladys Alexandre Modeling aerotaxis band formation in Azospirillum brasilense BMC Microbiology Chemotaxis Aerotaxis Band formation Azospirillum brasilense Mathematical modeling |
author_facet |
Mustafa Elmas Vasilios Alexiades Lindsey O’Neal Gladys Alexandre |
author_sort |
Mustafa Elmas |
title |
Modeling aerotaxis band formation in Azospirillum brasilense |
title_short |
Modeling aerotaxis band formation in Azospirillum brasilense |
title_full |
Modeling aerotaxis band formation in Azospirillum brasilense |
title_fullStr |
Modeling aerotaxis band formation in Azospirillum brasilense |
title_full_unstemmed |
Modeling aerotaxis band formation in Azospirillum brasilense |
title_sort |
modeling aerotaxis band formation in azospirillum brasilense |
publisher |
BMC |
series |
BMC Microbiology |
issn |
1471-2180 |
publishDate |
2019-05-01 |
description |
Abstract Background Bacterial chemotaxis, the ability of motile bacteria to navigate gradients of chemicals, plays key roles in the establishment of various plant-microbe associations, including those that benefit plant growth and crop productivity. The motile soil bacterium Azospirillum brasilense colonizes the rhizosphere and promotes the growth of diverse plants across a range of environments. Aerotaxis, or the ability to navigate oxygen gradients, is a widespread behavior in bacteria. It is one of the strongest behavioral responses in A. brasilense and it is essential for successful colonization of the root surface. Oxygen is one of the limiting nutrients in the rhizosphere where density and activity of organisms are greatest. The aerotaxis response of A. brasilense is also characterized by high precision with motile cells able to detect narrow regions in a gradient where the oxygen concentration is low enough to support their microaerobic lifestyle and metabolism. Results Here, we present a mathematical model for aerotaxis band formation that captures most critical features of aerotaxis in A. brasilense. Remarkably, this model recapitulates experimental observations of the formation of a stable aerotactic band within 2 minutes of exposure to the air gradient that were not captured in previous modeling efforts. Using experimentally determined parameters, the mathematical model reproduced an aerotactic band at a distance from the meniscus and with a width that matched the experimental observation. Conclusions Including experimentally determined parameter values allowed us to validate a mathematical model for aerotactic band formation in spatial gradients that recapitulates the spatiotemporal stability of the band and its position in the gradient as well as its overall width. This validated model also allowed us to capture the range of oxygen concentrations the bacteria prefer during aerotaxis, and to estimate the effect of parameter values (e.g. oxygen consumption rate), both of which are difficult to obtain in experiments. |
topic |
Chemotaxis Aerotaxis Band formation Azospirillum brasilense Mathematical modeling |
url |
http://link.springer.com/article/10.1186/s12866-019-1468-9 |
work_keys_str_mv |
AT mustafaelmas modelingaerotaxisbandformationinazospirillumbrasilense AT vasiliosalexiades modelingaerotaxisbandformationinazospirillumbrasilense AT lindseyoneal modelingaerotaxisbandformationinazospirillumbrasilense AT gladysalexandre modelingaerotaxisbandformationinazospirillumbrasilense |
_version_ |
1724845209146097664 |