Movatterモバイル変換

[0]ホーム
URL:

Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
Thehttps:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

NIH NLM Logo
Log inShow account info
Access keysNCBI HomepageMyNCBI HomepageMain ContentMain Navigation
pubmed logo
Advanced Clipboard
User Guide

Full text links

Atypon full text link Atypon Free PMC article
Full text links

Actions

Share

.2015 Oct;81(20):7098-105.
doi: 10.1128/AEM.01781-15. Epub 2015 Jul 31.

Quantitative Analysis of Lysobacter Predation

Affiliations

Quantitative Analysis of Lysobacter Predation

Ivana Seccareccia et al. Appl Environ Microbiol.2015 Oct.

Abstract

Bacteria of the genus Lysobacter are considered to be facultative predators that use a feeding strategy similar to that of myxobacteria. Experimental data supporting this assumption, however, are scarce. Therefore, the predatory activities of three Lysobacter species were tested in the prey spot plate assay and in the lawn predation assay, which are commonly used to analyze myxobacterial predation. Surprisingly, only one of the tested Lysobacter species showed predatory behavior in the two assays. This result suggested that not all Lysobacter strains are predatory or, alternatively, that the assays were not appropriate for determining the predatory potential of this bacterial group. To differentiate between the two scenarios, predation was tested in a CFU-based bioassay. For this purpose, defined numbers of Lysobacter cells were mixed together with potential prey bacteria featuring phenotypic markers, such as distinctive pigmentation or antibiotic resistance. After 24 h, cocultivated cells were streaked out on agar plates and sizes of bacterial populations were individually determined by counting the respective colonies. Using the CFU-based predation assay, we observed that Lysobacter spp. strongly antagonized other bacteria under nutrient-deficient conditions. Simultaneously, the Lysobacter population was increasing, which together with the killing of the cocultured bacteria indicated predation. Variation of the predator/prey ratio revealed that all three Lysobacter species tested needed to outnumber their prey for efficient predation, suggesting that they exclusively practiced group predation. In summary, the CFU-based predation assay not only enabled the quantification of prey killing and consumption by Lysobacter spp. but also provided insights into their mode of predation.

Copyright © 2015, American Society for Microbiology. All Rights Reserved.

PubMed Disclaimer

Figures

FIG 1
FIG 1
Effect of predators on different prey bacteria as determined by the prey spot plate assay. The table shows the mean (± 95% confidence interval [n = 3]) diameter of the lysis zone (in millimeters). Images depict spots of E. coli that have been coinoculated with a single colony of M. fulvus (A), L. capsici (B), L. enzymogenes (C), or L. oryzae (D) after 10 days of incubation.
FIG 2
FIG 2
Effect of predators on different prey bacteria as determined by the lawn predation assay. Shown is the mean swarm expansion (± 95% confidence interval [n = 3]) (in millimeters) of four species of predatory bacteria. Pairedt test: *,P < 0.05 between day 1 and day 10. All other comparisons were not significant (P > 0.05).
FIG 3
FIG 3
Effect of predators on different prey bacteria and vice versa as determined by the CFU-based predation assay. (A) Mean killing efficiency (ē; ± 95% confidence interval) of all three Lysobacter spp. tested against different species of prey bacteria (percent). Asterisks denote significant differences between the number of prey CFU of the control group (i.e., monocultures) and samples containing both predator and prey (i.e., cocultures) (Mann-Whitney U test: ***,P < 0.001 *,P < 0.05; #,P < 0.07; df = 2). (B) Mean prey utilization (ū; ± 95% confidence interval) of all three Lysobacter spp. tested against different species of prey bacteria (percent). Asterisks denote significant differences in the prey utilization when comparing control groups consisting exclusively of predators with samples containing both predators and prey (Wilcoxon test: *,P < 0.05; #,P < 0.07). n.d., prey species for whichu was not determined.
FIG 4
FIG 4
Frequency dependence of predatory efficiency. Shown are different predator/prey ratios versus the mean killing efficiency (ē; ± 95% confidence interval) of each predatory species. The number of B. subtilis CFU was held constant in all experiments.
FIG 5
FIG 5
Contact dependence of predatory behavior. The killing of the prey bacterium B. subtilis by Lysobacter cells and culture supernatants was analyzed in the CFU-based predation assay. Asterisks denote significant differences between the number of prey CFU of the control group and samples containing both predator and prey (Mann-Whitney U test: **,P < 0.01; df = 2).
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Faust K, Raes J. 2012. Microbial interactions: from networks to models. Nat Rev Microbiol 10:538–550. doi:10.1038/nrmicro2832. - DOI - PubMed
    1. Lidicker WZ., Jr 1979. A clarification of interactions in ecological systems. Bioscience 29:475–477. doi:10.2307/1307540. - DOI
    1. Abrams PA. 2000. The evolution of predator-prey interactions: theory and evidence. Annu Rev Ecol Syst 31:79–105. doi:10.1146/annurev.ecolsys.31.1.79. - DOI
    1. Jurkevitch E, Davidov Y. 2007. Phylogenetic diversity and evolution of predatory prokaryotes, p 1–56. In Jurkevitch E. (ed), Predatory prokaryotes—biology, ecology, and evolution. Springer, Heidelberg, Germany.
    1. Davidov Y, Jurkevitch E. 2004. Diversity and evolution of Bdellovibrio-and-like organisms (BALOs), reclassification of Bacteriovorax starrii as Peredibacterstarrii gen. nov., comb. nov., and description of the Bacteriovorax-Peredibacter clade as Bacteriovoracaceae fam. nov. Int J Syst Evol Microbiol 54:1439–1452. doi:10.1099/ijs.0.02978-0. - DOI - PubMed

Publication types

MeSH terms

LinkOut - more resources

Full text links
Atypon full text link Atypon Free PMC article
Cite
Send To

NCBI Literature Resources

MeSHPMCBookshelfDisclaimer

The PubMed wordmark and PubMed logo are registered trademarks of the U.S. Department of Health and Human Services (HHS). Unauthorized use of these marks is strictly prohibited.

[8]ページ先頭
©2009-2025 Movatter.jp