scholarly journals Differential response to prey quorum signals indicates predatory range of myxobacteria

2021 ◽  
Author(s):  
Shukria Akbar ◽  
Sandeep K. Misra ◽  
Joshua S. Sharp ◽  
David Cole Stevens
Keyword(s):  
Homoserine Lactone ◽  
Signaling Molecules ◽  
Biologically Active ◽  
Generalist Predators ◽  
Predator Prey ◽  
Specialized Metabolites ◽  
Acylhomoserine Lactone ◽  
Common Response ◽  
General Response ◽  
Insight Into

A potential keystone taxa, myxobacteria contribute to the microbial food web as generalist predators. However, the extent of myxobacterial impact on microbial community structure remains unknown. The chemical ecology of these predator-prey interactions provides insight into myxobacterial production of biologically active specialized metabolites used to benefit consumption of prey as well as the perception of quorum signals secreted by prey. Using comparative transcriptomics and metabolomics, we compared how the predatory myxobacteria Myxococcus xanthus and Cystobacter ferrugineus respond to structurally distinct exogenous quorum signaling molecules. Investigating acylhomoserine lactone (AHL) and quinolone type quorum signals used by the clinical pathogen Pseudomonas aeruginosa, we identified a general response to AHL signals from both myxobacteria as well as a unique response from C. ferrugineus when exposed to the quinolone signal 4-hydroxy-2-heptylquinolone (HHQ). Oxidative detoxification of HHQ in C. ferrugineus was not observed from M. xanthus. Subsequent predation assays indicated P. aeruginosa to be more susceptible to C. ferrugineus predation. These data indicate that as generalist predators myxobacteria demonstrate a common response to the ubiquitous AHL quorum signal class, and we suggest this response likely involves recognition of the homoserine lactone moiety of AHLs. We also suggest that oxidation of HHQ and superior predation of P. aeruginosa observed from C. ferrugineus provides an example of how prey signaling molecules impact predatory specialization of myxobacteria by influencing prey range.

scholarly journals Functional genomics study of Pseudomonas putida to determine traits associated with avoidance of a myxobacterial predator

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shukria Akbar ◽  
D. Cole Stevens
Keyword(s):  
Pseudomonas Putida ◽  
Bacterial Communities ◽  
Predator Avoidance ◽  
Phenotypic Diversity ◽  
Myxococcus Xanthus ◽  
Predator Prey ◽  
Mucoid Conversion ◽  
Small Colony ◽  
Predator Prey Models ◽  
Insight Into

AbstractPredation contributes to the structure and diversity of microbial communities. Predatory myxobacteria are ubiquitous to a variety of microbial habitats and capably consume a broad diversity of microbial prey. Predator–prey experiments utilizing myxobacteria have provided details into predatory mechanisms and features that facilitate consumption of prey. However, prey resistance to myxobacterial predation remains underexplored, and prey resistances have been observed exclusively from predator–prey experiments that included the model myxobacterium Myxococcus xanthus. Utilizing a predator–prey pairing that instead included the myxobacterium, Cystobacter ferrugineus, with Pseudomonas putida as prey, we observed surviving phenotypes capable of eluding predation. Comparative transcriptomics between P. putida unexposed to C. ferrugineus and the survivor phenotype suggested that increased expression of efflux pumps, genes associated with mucoid conversion, and various membrane features contribute to predator avoidance. Unique features observed from the survivor phenotype when compared to the parent P. putida include small colony variation, efflux-mediated antibiotic resistance, phenazine-1-carboxylic acid production, and increased mucoid conversion. These results demonstrate the utility of myxobacterial predator–prey models and provide insight into prey resistances in response to predatory stress that might contribute to the phenotypic diversity and structure of bacterial communities.

scholarly journals Inhibition of Quorum Sensing in Serratia marcescens AS-1 by Synthetic Analogs of N-Acylhomoserine Lactone

2007 ◽  
Vol 73 (20) ◽  
pp. 6339-6344 ◽  
Author(s):  
Tomohiro Morohoshi ◽  
Toshitaka Shiono ◽  
Kiyomi Takidouchi ◽  
Masashi Kato ◽  
Norihiro Kato ◽  
...  
Keyword(s):  
Quorum Sensing ◽  
Serratia Marcescens ◽  
Biofilm Formation ◽  
Acyl Chain ◽  
Regulatory System ◽  
Homoserine Lactone ◽  
Signal Molecule ◽  
Swarming Motility ◽  
Gram Negative ◽  
Acylhomoserine Lactone

ABSTRACT Quorum sensing is a regulatory system for controlling gene expression in response to increasing cell density. N-Acylhomoserine lactone (AHL) is produced by gram-negative bacteria, which use it as a quorum-sensing signal molecule. Serratia marcescens is a gram-negative opportunistic pathogen which is responsible for an increasing number of serious nosocomial infections. S. marcescens AS-1 produces N-hexanoyl homoserine lactone (C6-HSL) and N-(3-oxohexanoyl) homoserine lactone and regulates prodigiosin production, swarming motility, and biofilm formation by AHL-mediated quorum sensing. We synthesized a series of N-acyl cyclopentylamides with acyl chain lengths ranging from 4 to 12 and estimated their inhibitory effects on prodigiosin production in AS-1. One of these molecules, N-nonanoyl-cyclopentylamide (C9-CPA), had a strong inhibitory effect on prodigiosin production. C9-CPA also inhibited the swarming motility and biofilm formation of AS-1. A competition assay revealed that C9-CPA was able to inhibit quorum sensing at four times the concentration of exogenous C6-HSL and was more effective than the previously reported halogenated furanone. Our results demonstrated that C9-CPA was an effective quorum-sensing inhibitor for S. marcescens AS-1.

Cell-Based Biosensors Based on Intein-Mediated Protein Engineering for Detection of Biologically Active Signaling Molecules

2018 ◽  
Vol 90 (16) ◽  
pp. 9779-9786 ◽  
Author(s):  
Hyunjin Jeon ◽  
Euiyeon Lee ◽  
Dahee Kim ◽  
Minhyung Lee ◽  
Jeahee Ryu ◽  
...  
Keyword(s):  
Protein Engineering ◽  
Signaling Molecules ◽  
Biologically Active

Predator–prey interactions and climate change

2019 ◽  
pp. 199-220 ◽  
Author(s):  
Vincent Bretagnolle ◽  
Julien Terraube
Keyword(s):  
Climate Change ◽  
Species Interactions ◽  
Experimental Studies ◽  
Trophic Levels ◽  
Generalist Predators ◽  
Top Down ◽  
Predator Prey ◽  
Key Topics ◽  
Available Information

Climate change is likely to impact all trophic levels, although the response of communities and ecosystems to it has only recently received considerable attention. Further, it is expected to affect the magnitude of species interactions themselves. In this chapter, we summarize why and how climate change could affect predator–prey interactions, then review the literature about its impact on predator–prey relationships in birds, and provide prospects for future studies. Expected effects on prey or predators may include changes in the following: distribution, phenology, population density, behaviour, morphology, or physiology. We review the currently available information concerning particular key topics: top-down versus bottom-up control, specialist versus generalist predators, functional versus numerical responses, trophic cascades and regime shifts, and lastly adaptation and selection. Finally, we focus our review on two well-studied bird examples: seabirds and raptors. Key future topics include long-term studies, modelling and experimental studies, evolutionary questions, and conservation issues.

scholarly journals Exquisitely Preserved Fossil Snakes of Messel: Insight into the Evolution, Biogeography, Habitat Preferences and Sensory Ecology of Early Boas

Diversity ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 100 ◽  
Author(s):  
Agustín Scanferla ◽  
Krister T. Smith
Keyword(s):  
Body Size ◽  
New World ◽  
Middle Eocene ◽  
Habitat Preferences ◽  
Sensory Ecology ◽  
Morphological Diversity ◽  
Predator Prey ◽  
Upper Jaw ◽  
Spectrum Evaluation ◽  
Insight Into

Our knowledge of early evolution of snakes is improving, but all that we can infer about the evolution of modern clades of snakes such as boas (Booidea) is still based on isolated bones. Here, we resolve the phylogenetic relationships of Eoconstrictor fischeri comb. nov. and other booids from the early-middle Eocene of Messel (Germany), the best-known fossil snake assemblage yet discovered. Our combined analyses demonstrate an affinity of Eoconstrictor with Neotropical boas, thus entailing a South America-to-Europe dispersal event. Other booid species from Messel are related to different New World clades, reinforcing the cosmopolitan nature of the Messel booid fauna. Our analyses indicate that Eoconstrictor was a terrestrial, medium- to large-bodied snake that bore labial pit organs in the upper jaw, the earliest evidence that the visual system in snakes incorporated the infrared spectrum. Evaluation of the known palaeobiology of Eoconstrictor provides no evidence that pit organs played a role in the predator–prey relations of this stem boid. At the same time, the morphological diversity of Messel booids reflects the occupation of several terrestrial macrohabitats, and even in the earliest booid community the relation between pit organs and body size is similar to that seen in booids today.

scholarly journals An Unprecedented Medium-Chain Diunsaturated N-acylhomoserine Lactone from Marine Roseobacter Group Bacteria

Marine Drugs ◽  
2018 ◽  
Vol 17 (1) ◽  
pp. 20 ◽  
Author(s):  
Lisa Ziesche ◽  
Laura Wolter ◽  
Hui Wang ◽  
Thorsten Brinkhoff ◽  
Marion Pohlner ◽  
...  
Keyword(s):  
Quorum Sensing ◽  
Acyl Chain ◽  
Homoserine Lactone ◽  
Compound Identification ◽  
Structural Element ◽  
Mass Spectral ◽  
Acylhomoserine Lactone ◽  
The North ◽  
Bacterial Signaling ◽  
Roseobacter Group

N-acylhomoserine lactones (AHLs), bacterial signaling compounds involved in quorum-sensing, are a structurally diverse group of compounds. We describe here the identification, synthesis, occurrence and biological activity of a new AHL, N-((2E,5Z)-2,5-dodecadienoyl)homoserine lactone (11) and its isomer N-((3E,5Z)-3,5-dodecadienoyl)homoserine lactone (13), occurring in several Roseobacter group bacteria (Rhodobacteraceae). The analysis of 26 strains revealed the presence of 11 and 13 in six of them originating from the surface of the macroalgae Fucus spiralis or sediments from the North Sea. In addition, 18 other AHLs were detected in 12 strains. Compound identification was performed by GC/MS. Mass spectral analysis revealed a diunsaturated C12 homoserine lactone as structural element of the new AHL. Synthesis of three likely candidate compounds, 11, 13 and N-((2E,4E)-2,4-dodecadienoyl)homoserine lactone (5), revealed the former to be the natural AHLs. Bioactivity test with quorum-sensing reporter strains showed high activity of all three compounds. Therefore, the configuration and stereochemistry of the double bonds in the acyl chain seemed to be unimportant for the activity, although the chains have largely different shapes, solely the chain length determining activity. In combination with previous results with other Roseobacter group bacteria, we could show that there is wide variance between AHL composition within the strains. Furthermore, no association of certain AHLs with different habitats like macroalgal surfaces or sediment could be detected.

Sign in / Sign up

Export Citation Format

Share Document