Study of the ability of Bacillus toyonensis to interfere with the quorum-sensing systems of enterotoxigenic Escherichia coli K88 in the pig gut

ABSTRACTBacterial rapid surfing motility is a novel surface adaptation ofPseudomonas aeruginosain the presence of the glycoprotein mucin. Here, we show that other Gram-negative motile bacterial species, includingEscherichia coli,Salmonella enterica,Vibrio harveyi,Enterobacter cloacae, andProteus mirabilis, also exhibit the physical characteristics of surfing on the surface of agar plates containing 0.4% mucin, where surfing motility was generally more rapid and less dependent on medium viscosity than was swimming motility. As previously observed inPseudomonas aeruginosa, all surfing species exhibited some level of broad-spectrum adaptive resistance, although the antibiotics to which they demonstrated surfing-mediated resistance differed. Surfing motility inP. aeruginosawas found to be dependent on the quorum-sensing systems of this organism; however, this aspect was not conserved in other tested bacterial species, includingV. harveyiandS. enterica, as demonstrated by assaying specific quorum-sensing mutants. Thus, rapid surfing motility is a complex surface growth adaptation that is conserved in several motile bacteria, involves flagella, and leads to diverse broad-spectrum antibiotic resistance, but it is distinct in terms of dependence on quorum sensing.IMPORTANCEThis study showed for the first time that surfing motility, a novel form of surface motility first discovered inPseudomonas aeruginosaunder artificial cystic fibrosis conditions, including the presence of high mucin content, is conserved in other motile bacterial species known to be mucosa-associated, includingEscherichia coli,Salmonella enterica, andProteus mirabilis. Here, we demonstrated that key characteristics of surfing, including the ability to adapt to various viscous environments and multidrug adaptive resistance, are also conserved. Using mutagenesis assays, we also identified the importance of all three known quorum-sensing systems, Las, Rhl, and Pqs, inP. aeruginosain regulating surfing motility, and we also observed a conserved dependence of surfing on flagella in certain species.

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The Effect of Furanone on Enterotoxigenic Escherichia Coli (ETEC) O139 Transcriptome Was Analyzed Using RNA-seq

10.21203/rs.3.rs-117288/v1 ◽

2020 ◽

Author(s):

Jing-He Li ◽

Jia-Lin Yu ◽

Qiang An ◽

Chun-Lei Zhang ◽

Peng-Fei Yi

Keyword(s):

Escherichia Coli ◽

Quorum Sensing ◽

Virulence Factors ◽

Biofilm Formation ◽

Homoserine Lactone ◽

Enterotoxigenic Escherichia Coli ◽

Biological Behavior ◽

Signal Molecules ◽

Rna Seq ◽

Safe Food

Abstract Background: In recent years, the effective ingredients of some medicine play an anti-infection role in inhibiting the formation of bacterial virulence factors and biofilm without affecting the growth of bacteria, which can reduce the survival pressure of bacteria and is not easy to develop drug resistance. It is considered to be a better way to control the infection of pathogenic microorganisms. Bacteria can produce signal molecules called auto-inducers (AIs) which can sense the bacteria density change. When auto-inducers accumulate to the threshold, they will regulate the bacteria biological behavior to adapt the changes of environment, including the formation of biofilm, virulence factors and bioluminescence. This is quorum sensing (QS).4-Hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF) is a non-halogenated furanone found in strawberries, pineapples and other fruits and widely used as a safe food additive in beverages, ice cream and cigarettes. At present, there are lots of studies about furanone. Previous studies have shown that this kind of compound can compete with Acyl-homoserine lactone (AHL) in binding with its receptors, which inhibits the initiation of quorum sensing system. Results: In recent years, few studies about the transcriptome analysis of the furanone interacting with Enterotoxigenic Escherichia coli (ETEC) were reported. Therefore, we analyzed the effect of furanone on ETEC O139 transcriptome by RNA-seq. The result show that genes related to QS did not change after the interaction of 10μg/ml furanone and ETEC O139, while the expression of some genes related to the pathogenicity of ETEC O139 increased, such as flagellum assembly, biofilm formation and adhesion and so on.Conclusions: 10μg/ml furanone have no influence on QS system, but could contribute to adhesion, invasion, flagellum assembly and biofilm formation of ETEC O139.

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Genetic and functional diversity of PsyI/PsyR quorum-sensing system in the Pseudomonas syringae complex

FEMS Microbiology Ecology ◽

10.1093/femsec/fiaa254 ◽

2020 ◽

Author(s):

Tomohiro Morohoshi ◽

Akinori Oshima ◽

Xiaonan Xie ◽

Nobutaka Someya

Keyword(s):

Escherichia Coli ◽

Quorum Sensing ◽

Pseudomonas Syringae ◽

Dna Sequences ◽

Homoserine Lactone ◽

Sensing System ◽

Sensing Systems ◽

Quorum Sensing System ◽

High Level ◽

Functionally Diverse

Abstract Strains belonging to the Pseudomonas syringae complex often possess quorum-sensing systems that comprise N-acyl-l-homoserine lactone (AHL) synthase (PsyI) and AHL receptors (PsyR). Here, we investigated the diversity of PsyI/PsyR quorum-sensing systems in 630 strains of the P. syringae complex. AHL production was observed in most strains of P. amygdali and P. meliae, and a few strains of P. coronafaciens and P. syringae. The DNA sequences of psyIR and their upstream and downstream regions were categorized into eight types. P. amygdali pv. myricae, P. savastanoi, and P. syringae pv. solidagae, maculicola, broussonetiae, and tomato encoded psyI, but did not produce detectable amounts of AHL. In P. savastanoi, an amino acid substitution (R27S) in PsyI caused defective AHL production. The psyI gene of P. syringae pv. tomato was converted to pseudogenes by frameshift mutations. Escherichia coli harboring psyI genes from P. amygdali pv. myricae, P. syringae pv. solidagae and broussonetiae showed high level of AHL production. Forced expression of functional psyR restored AHL production in P. amygdali pv. myricae and P. syringae pv. solidagae. In conclusion, our study indicates that the PsyI/PsyR quorum-sensing systems in P. syringae strains are genetically and functionally diverse, with diversity being linked to phylogenetic and pathovar classifications.

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Engineered Orthogonal Quorum Sensing Systems for Synthetic Gene Regulation in Escherichia coli

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2019.00080 ◽

2019 ◽

Vol 7 ◽

Cited By ~ 5

Author(s):

Stefan J. Tekel ◽

Christina L. Smith ◽

Brianna Lopez ◽

Amber Mani ◽

Christopher Connot ◽

...

Keyword(s):

Escherichia Coli ◽

Gene Regulation ◽

Quorum Sensing ◽

Synthetic Gene ◽

Sensing Systems

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Engineered orthogonal quorum sensing systems for synthetic gene regulation

10.1101/499681 ◽

2018 ◽

Author(s):

Stefan J. Tekel ◽

Christina L. Smith ◽

Brianna Lopez ◽

Amber Mani ◽

Christopher Connot ◽

...

Keyword(s):

Escherichia Coli ◽

Quorum Sensing ◽

Signaling Pathways ◽

Gene Networks ◽

Synthetic Gene ◽

Synthetic Gene Networks ◽

Homoserine Lactones ◽

Signaling Systems ◽

Sensing Systems ◽

Engineered Bacteria

AbstractGene regulators that are controlled by membrane-permeable compounds called Homoserine lactones (HSLs) have become popular tools for building synthetic gene networks that coordinate behaviors across populations of engineered bacteria. Synthetic HSL-signaling systems are derived from natural DNA and protein elements from microbial quorum signaling pathways. Crosstalk, where a single HSL can activate multiple regulators, can lead to faults in networks composed of parallel signaling pathways. Here, we report an investigation of quorum sensing components to identify synthetic pathways that exhibit little to no crosstalk in liquid and solid cultures. In previous work, we characterized the response of a single regulator (LuxR) to ten distinct HSL-synthase enzymes. Our current study determined the responses of five different regulators (LuxR, LasR, TraR, BjaR, and AubR) to the same set of synthases. We identified two sets of orthogonal synthase-regulator pairs (BjaI/BjaR + EsaI/TraR and LasI/LasR + EsaI/TraR) that show little to no crosstalk when they are expressed in Escherichia coli BL21. These results expand the toolbox of characterized components for engineering microbial communities.

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