Identification of NewN-Acylhomoserine Lactone Signalling Compounds ofDinoroseobacter shibaeDFL-12Tby Overexpression ofluxIGenes

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.

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A novel medium for the isolation of N-acylhomoserine lactone-degrading bacteria

Journal of Industrial Microbiology & Biotechnology ◽

10.1007/s10295-008-0491-x ◽

2008 ◽

Vol 36 (2) ◽

pp. 247-251 ◽

Cited By ~ 49

Author(s):

Kok-Gan Chan ◽

Wai-Fong Yin ◽

Choon-Kook Sam ◽

Chong-Lek Koh

Keyword(s):

Acylhomoserine Lactone ◽

Degrading Bacteria

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Comparative genome analysis reveals the presence of multiple quorum-sensing systems in plant pathogenic bacterium, Erwinia rhapontici

Bioscience Biotechnology and Biochemistry ◽

10.1093/bbb/zbab104 ◽

2021 ◽

Author(s):

Tomohiro Morohoshi ◽

Kanako Nameki ◽

Nobutaka Someya

Keyword(s):

Gene Pair ◽

Large Scale ◽

Insertion Sequence ◽

Plant Pathogenic Bacterium ◽

Comparative Genome Analysis ◽

Genome Sequences ◽

Indigenous Plasmid ◽

Acylhomoserine Lactone ◽

Sensing Systems ◽

Erwinia Rhapontici

Abstract We present the complete genome sequences of three Erwinia rhapontici strains, MAFF 311153, 311154, and 311155. These chromosome sequences contained variety types of luxI/luxR gene pair involved in acylhomoserine lactone (AHL) biosynthesis and reception. Large-scale insertion sequence was observed in the indigenous plasmid of MAFF 311154 and contained eraI3/eraR3 gene pair which make possible to produce acylhomoserine lactone.

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The natural history of defences

10.1093/oso/9780198832140.003.0004 ◽

2021 ◽

pp. 51-108

Author(s):

Paul Schmid-Hempel

Keyword(s):

Innate Immunity ◽

Natural History ◽

Adaptive Immunity ◽

Immune Memory ◽

History Of ◽

Molecular Backbone ◽

Somatic Diversification ◽

Signalling Compounds ◽

Immune Defences ◽

Signalling Cascade

Hosts can avoid infections by behavioural changes and by body walls. After infection, hosts can change their behaviours to reduce the effects of parasitism. Immune defences have different arms (humoral or cellular), and organization (innate, adaptive). Innate immunity consists of a collection of different systems that are evolutionarily very old. Adaptive immunity, based on expansion of specific lymphocytes, evolved in the higher vertebrates. Immune defences are regulated tightly and based on receptors that can recognize parasites (or their activity). This triggers a complex signalling cascade that results in the production of further signalling compounds and effectors. Important protein families, e.g. the immunoglobulins, form the molecular backbone. A key to efficient defences is the diversification of receptors, such as the highly evolved somatic diversification processes of advanced adaptive immunity. The microbiota adds to defences in many ways. Immune memory and priming occur throughout the tree of life.

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

Marine Drugs ◽

10.3390/md17010020 ◽

2018 ◽

Vol 17 (1) ◽

pp. 20 ◽

Cited By ~ 2

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.

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