Behavioral Interactions between Bacterivorous Nematodes and Predatory Bacteria in a Synthetic Community
Theory and empirical studies in metazoans predict that apex predators should shape the behavior and ecology of mesopredators and prey at lower trophic levels. Despite the ecological importance of microbial communities, few studies of predatory microbes examine such behavioral res-ponses and the mult...
Main Authors: | , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
MDPI AG
2021-06-01
|
Series: | Microorganisms |
Subjects: | |
Online Access: | https://www.mdpi.com/2076-2607/9/7/1362 |
_version_ | 1797529041717166080 |
---|---|
author | Nicola Mayrhofer Gregory J. Velicer Kaitlin A. Schaal Marie Vasse |
author_facet | Nicola Mayrhofer Gregory J. Velicer Kaitlin A. Schaal Marie Vasse |
author_sort | Nicola Mayrhofer |
collection | DOAJ |
description | Theory and empirical studies in metazoans predict that apex predators should shape the behavior and ecology of mesopredators and prey at lower trophic levels. Despite the ecological importance of microbial communities, few studies of predatory microbes examine such behavioral res-ponses and the multiplicity of trophic interactions. Here, we sought to assemble a three-level microbial food chain and to test for behavioral interactions between the predatory nematode <i>Caenorhabditis elegans</i> and the predatory social bacterium <i>Myxococcus xanthus</i> when cultured together with two basal prey bacteria that both predators can eat—<i>Escherichia coli</i> and <i>Flavobacterium johnsoniae</i>. We found that >90% of <i>C. elegans</i> worms failed to interact with <i>M. xanthus</i> even when it was the only potential prey species available, whereas most worms were attracted to pure patches of <i>E. coli</i> and <i>F. johnsoniae.</i> In addition, <i>M. xanthus</i> altered nematode predatory behavior on basal prey, repelling <i>C. elegans</i> from two-species patches that would be attractive without <i>M. xanthus</i>, an effect similar to that of <i>C. elegans</i> pathogens. The nematode also influenced the behavior of the bacterial predator: <i>M. xanthus</i> increased its predatory swarming rate in response to <i>C. elegans</i> in a manner dependent both on basal-prey identity and on worm density. Our results suggest that <i>M. xanthus</i> is an unattractive prey for some soil nematodes and is actively avoided when other prey are available. Most broadly, we found that nematode and bacterial predators mutually influence one another’s predatory behavior, with likely consequences for coevolution within complex microbial food webs. |
first_indexed | 2024-03-10T10:07:51Z |
format | Article |
id | doaj.art-c65cadd298ca4e0da19f409b6c82abb5 |
institution | Directory Open Access Journal |
issn | 2076-2607 |
language | English |
last_indexed | 2024-03-10T10:07:51Z |
publishDate | 2021-06-01 |
publisher | MDPI AG |
record_format | Article |
series | Microorganisms |
spelling | doaj.art-c65cadd298ca4e0da19f409b6c82abb52023-11-22T01:23:53ZengMDPI AGMicroorganisms2076-26072021-06-0197136210.3390/microorganisms9071362Behavioral Interactions between Bacterivorous Nematodes and Predatory Bacteria in a Synthetic CommunityNicola Mayrhofer0Gregory J. Velicer1Kaitlin A. Schaal2Marie Vasse3Institute of Integrative Biology, ETH Zürich, Universitätstrasse 16, 8092 Zürich, SwitzerlandInstitute of Integrative Biology, ETH Zürich, Universitätstrasse 16, 8092 Zürich, SwitzerlandInstitute of Integrative Biology, ETH Zürich, Universitätstrasse 16, 8092 Zürich, SwitzerlandInstitute of Integrative Biology, ETH Zürich, Universitätstrasse 16, 8092 Zürich, SwitzerlandTheory and empirical studies in metazoans predict that apex predators should shape the behavior and ecology of mesopredators and prey at lower trophic levels. Despite the ecological importance of microbial communities, few studies of predatory microbes examine such behavioral res-ponses and the multiplicity of trophic interactions. Here, we sought to assemble a three-level microbial food chain and to test for behavioral interactions between the predatory nematode <i>Caenorhabditis elegans</i> and the predatory social bacterium <i>Myxococcus xanthus</i> when cultured together with two basal prey bacteria that both predators can eat—<i>Escherichia coli</i> and <i>Flavobacterium johnsoniae</i>. We found that >90% of <i>C. elegans</i> worms failed to interact with <i>M. xanthus</i> even when it was the only potential prey species available, whereas most worms were attracted to pure patches of <i>E. coli</i> and <i>F. johnsoniae.</i> In addition, <i>M. xanthus</i> altered nematode predatory behavior on basal prey, repelling <i>C. elegans</i> from two-species patches that would be attractive without <i>M. xanthus</i>, an effect similar to that of <i>C. elegans</i> pathogens. The nematode also influenced the behavior of the bacterial predator: <i>M. xanthus</i> increased its predatory swarming rate in response to <i>C. elegans</i> in a manner dependent both on basal-prey identity and on worm density. Our results suggest that <i>M. xanthus</i> is an unattractive prey for some soil nematodes and is actively avoided when other prey are available. Most broadly, we found that nematode and bacterial predators mutually influence one another’s predatory behavior, with likely consequences for coevolution within complex microbial food webs.https://www.mdpi.com/2076-2607/9/7/1362microbial food webtrophic interactionspredator–prey interactionsmesopredatorsocial bacterianematodes |
spellingShingle | Nicola Mayrhofer Gregory J. Velicer Kaitlin A. Schaal Marie Vasse Behavioral Interactions between Bacterivorous Nematodes and Predatory Bacteria in a Synthetic Community Microorganisms microbial food web trophic interactions predator–prey interactions mesopredator social bacteria nematodes |
title | Behavioral Interactions between Bacterivorous Nematodes and Predatory Bacteria in a Synthetic Community |
title_full | Behavioral Interactions between Bacterivorous Nematodes and Predatory Bacteria in a Synthetic Community |
title_fullStr | Behavioral Interactions between Bacterivorous Nematodes and Predatory Bacteria in a Synthetic Community |
title_full_unstemmed | Behavioral Interactions between Bacterivorous Nematodes and Predatory Bacteria in a Synthetic Community |
title_short | Behavioral Interactions between Bacterivorous Nematodes and Predatory Bacteria in a Synthetic Community |
title_sort | behavioral interactions between bacterivorous nematodes and predatory bacteria in a synthetic community |
topic | microbial food web trophic interactions predator–prey interactions mesopredator social bacteria nematodes |
url | https://www.mdpi.com/2076-2607/9/7/1362 |
work_keys_str_mv | AT nicolamayrhofer behavioralinteractionsbetweenbacterivorousnematodesandpredatorybacteriainasyntheticcommunity AT gregoryjvelicer behavioralinteractionsbetweenbacterivorousnematodesandpredatorybacteriainasyntheticcommunity AT kaitlinaschaal behavioralinteractionsbetweenbacterivorousnematodesandpredatorybacteriainasyntheticcommunity AT marievasse behavioralinteractionsbetweenbacterivorousnematodesandpredatorybacteriainasyntheticcommunity |