Decoding the mystery of how bacteria “talk”: Among Gram-negative microorganisms

To date, microbial diversity is still the least well understood component of biodiversity. Bacteria are the most abundant microorganisms where most species are often found ubiquitous. Microorganisms such as bacteria are diverse in their impacts such as in spreading of infectious diseases or play a valuable role in biotechnological purposes. Hence, it is interesting to gain a look upon the ways where bacteria regulate their daily processes in the environment. Bacteria communicate with each other through extracellular signalling molecules or also known as autoinducers (AIs) that are produced, detected and show response. This process is termed as quorum sensing (QS) which indicates that bacteria do communicate in order to perform various physiological activities. QS enable bacteria to have the advantages that are unattainable as individual bacterial cell. This review emphases on the characteristics of quorum sensing (QS) and its benefits in understanding different kind of bacterial QS-dependent activities. This fundamental insight from QS system will enable us to manage bacterial activities by targeting their communication circuit.

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How do we de-escalate therapy for Gram-negative nosocomial infections in an infectious diseases intensive care unit?

10.26226/morressier.56d5ba30d462b80296c95508 ◽

2016 ◽

Author(s):

Diana Neves

Keyword(s):

Intensive Care Unit ◽

Intensive Care ◽

Infectious Diseases ◽

Nosocomial Infections ◽

Gram Negative

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Faculty Opinions recommendation of In Vitro Model of the Gram-Negative Bacterial Cell Envelope for Investigation of Anti-Infective Permeation Kinetics.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.733245095.793563395 ◽

2019 ◽

Author(s):

Erin Carlson

Keyword(s):

Bacterial Cell ◽

In Vitro Model ◽

Cell Envelope ◽

Gram Negative ◽

Bacterial Cell Envelope ◽

Vitro Model ◽

Permeation Kinetics

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The Quorum Sensing Auto-Inducer 2 (AI-2) Stimulates Nitrogen Fixation and Favors Ethanol Production over Biomass Accumulation in Zymomonas mobilis

International Journal of Molecular Sciences ◽

10.3390/ijms22115628 ◽

2021 ◽

Vol 22 (11) ◽

pp. 5628

Author(s):

Valquíria Campos Alencar ◽

Juliana de Fátima dos Santos Silva ◽

Renata Ozelami Vilas Boas ◽

Vinícius Manganaro Farnézio ◽

Yara N. L. F. de Maria ◽

...

Keyword(s):

Nitrogen Fixation ◽

Quorum Sensing ◽

Ethanol Production ◽

N2 Fixation ◽

Energy Demand ◽

Zymomonas Mobilis ◽

Biomass Accumulation ◽

High Energy ◽

Gram Negative ◽

Expression Of Genes

Autoinducer 2 (or AI-2) is one of the molecules used by bacteria to trigger the Quorum Sensing (QS) response, which activates expression of genes involved in a series of alternative mechanisms, when cells reach high population densities (including bioluminescence, motility, biofilm formation, stress resistance, and production of public goods, or pathogenicity factors, among others). Contrary to most autoinducers, AI-2 can induce QS responses in both Gram-negative and Gram-positive bacteria, and has been suggested to constitute a trans-specific system of bacterial communication, capable of affecting even bacteria that cannot produce this autoinducer. In this work, we demonstrate that the ethanologenic Gram-negative bacterium Zymomonas mobilis (a non-AI-2 producer) responds to exogenous AI-2 by modulating expression of genes involved in mechanisms typically associated with QS in other bacteria, such as motility, DNA repair, and nitrogen fixation. Interestingly, the metabolism of AI-2-induced Z. mobilis cells seems to favor ethanol production over biomass accumulation, probably as an adaptation to the high-energy demand of N2 fixation. This opens the possibility of employing AI-2 during the industrial production of second-generation ethanol, as a way to boost N2 fixation by these bacteria, which could reduce costs associated with the use of nitrogen-based fertilizers, without compromising ethanol production in industrial plants.

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Molecular Dynamics Simulation of the Interaction of Two Linear Battacin Analogs with Model Gram-Positive and Gram-Negative Bacterial Cell Membranes

ACS Omega ◽

10.1021/acsomega.0c04752 ◽

2020 ◽

Author(s):

Aparajita Chakraborty ◽

Elisey Kobzev ◽

Jonathan Chan ◽

Gayan Heruka de Zoysa ◽

Vijayalekshmi Sarojini ◽

...

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulation ◽

Bacterial Cell ◽

Cell Membranes ◽

Dynamics Simulation ◽

Gram Positive ◽

Gram Negative

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Environmental modification via a quorum sensing molecule influences the social landscape of siderophore production

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2017.0200 ◽

2017 ◽

Vol 284 (1852) ◽

pp. 20170200 ◽

Cited By ~ 22

Author(s):

Roman Popat ◽

Freya Harrison ◽

Ana C. da Silva ◽

Scott A. S. Easton ◽

Luke McNally ◽

...

Keyword(s):

Quorum Sensing ◽

Public Goods ◽

Bacterial Species ◽

Relative Fitness ◽

Iron Starvation ◽

Signal Molecule ◽

Signalling Molecules ◽

Signalling Molecule ◽

The Impact ◽

Social Trait

Bacteria produce a wide variety of exoproducts that favourably modify their environment and increase their fitness. These are often termed ‘public goods’ because they are costly for individuals to produce and can be exploited by non-producers (cheats). The outcome of conflict over public goods is dependent upon the prevailing environment and the phenotype of the individuals in competition. Many bacterial species use quorum sensing (QS) signalling molecules to regulate the production of public goods. QS, therefore, determines the cooperative phenotype of individuals, and influences conflict over public goods. In addition to their regulatory functions, many QS molecules have additional properties that directly modify the prevailing environment. This leads to the possibility that QS molecules could influence conflict over public goods indirectly through non-signalling effects, and the impact of this on social competition has not previously been explored. The Pseudomonas aeruginosa QS signal molecule PQS is a powerful chelator of iron which can cause an iron starvation response. Here, we show that PQS stimulates a concentration-dependent increase in the cooperative production of iron scavenging siderophores, resulting in an increase in the relative fitness of non-producing siderophore cheats. This is likely due to an increased cost of siderophore output by producing cells and a concurrent increase in the shared benefits, which accrue to both producers and cheats. Although PQS can be a beneficial signalling molecule for P. aeruginosa , our data suggest that it can also render a siderophore-producing population vulnerable to competition from cheating strains. More generally, our results indicate that the production of one social trait can indirectly affect the costs and benefits of another social trait.

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Draft Genome Sequence of Pantoea sp. Strain A4, a Rafflesia-Associated Bacterium That ProducesN-Acylhomoserine Lactones as Quorum-Sensing Molecules

Journal of Bacteriology ◽

10.1128/jb.01619-12 ◽

2012 ◽

Vol 194 (23) ◽

pp. 6610-6610 ◽

Cited By ~ 12

Author(s):

Kar-Wai Hong ◽

Han Ming Gan ◽

Siew-Moon Low ◽

Patrick Kok Yuen Lee ◽

Yee-Meng Chong ◽

...

Keyword(s):

Quorum Sensing ◽

Genome Sequence ◽

Draft Genome ◽

Draft Genome Sequence ◽

Negative Bacterium ◽

Gram Negative ◽

Content Type ◽

First Time

ABSTRACTPantoeasp. strain A4 is a Gram-negative bacterium isolated from theRafflesiaflower. We present here, for the first time, the genome sequence ofRafflesia-associatedPantoeasp. strain A4, which exhibited quorum-sensing activity.

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