Microbial Communication System

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DEPARTMENTAL SEMINAR
Topics Microbial Communication System
Presented By-
Jausrang.B Years
2017 DEPARTMENT OF BIOTECHNOLOGY
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CONTENTS

• INTRODUCTION
• QUORUM SENSING
• OCCURANCE
• GRAM POSITIVE BACTERIA
• GRAM NEGATIVE BACTERIA
• APPLICATION OF QUORUM SENSING
• CONCLUSION

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INTRODUCTION

• In their natural habitats microorganism live in
  permanent exchange with their environment
  surrounding microbes and higher organism.

• Microbial communication, cooperation and
  cheating, quorum sensing drives the evolution of
  cooperation in bacteria.

• The regulation of gene expression in response to
  fluctuations in cell population density Produce
  and release signal molecules into the environment
  , auto inducers.

• The communication between different cell is
  continuous in order to maintain, balancing and
  homeostasis

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• Quorum Sensing is a Latin Word.
• It means the number of members of a group
  required to be present to transact or carry out
  an activity of legally.
• In this process bacteria can connect via secreted
  signals molecules called Autoinducer which
  contribute to the regulations of the expansion of
  particular genes.

Quorum Sensing

• Quorum sensing as a population-density-dependent
  determinant of bacterial physiology.

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QUORUM SENSING BACTERIA
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HISTORY QUORUM SENSING
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Occurance

• Occurs within a single bacterial species known as
  Intraspecies Communication.
• Occurs between different bacterial population
  known as Interspecies communication.
• These Occurs between bacteria and other organism
  known as Interkingdom Communication.

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Gram positive Bacteria

• Intercellular communication is also used by gram
  positive pathogens to control virulence. By using
  AHL based sgnaling molecules and detection of
  modified oligopeptide called Autoinducing
  peptide(AIPs).

• Autoinducer- peptide (oligopeptides)
• Secreted by ABC transporter (ATP binding
  cassette transporter.
• Example Bacillus subtilis Streptococcus
  pneumonia use to develop bacterial competence.

• Peptide signal works by binding a sensor protein
  histadine kinase located in the cell membrane of
  the bacteria .Histadine kinase become activated.
• Peptide used as autoinducer in Gram positive
  Quorum sensing is secreted through ATP binding
  cassette transport(ABC).

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MECHANISM OF GRAM BACTERIA
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Gram Negative Bacteria
Acylhomoserine lactone (AHL) signaling

• The lux type quorum sensing system is the
  mechanism species specific communication in gram
  negative bacteria. The lux quorum sensing is
  based on the production of and response to AHSs.
• In general lux system consist of two component
  autoinducer with synthesis AHLs and
  transcriptional regulator(luxR).Because of its
  small size and lipophilic character. AHL freely
  diffuse across cell membranes. As the population
  density increase intracellular AHL bind the
  functional linked LuxR like receptor at a
  sufficient concentration with cytoplasm to induce
  different gene expression.

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Gram negative Bacteria
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Application of Quorum Sensing

• Biosensor It is an interesting application of
  quorum sensing whole cell microbial biosensor
  can distinguish pathogenic microbe present in
  environment with disease organism.
• Pathogen diagnostics
• Cancer Detection.
• Recombinant gene expression.

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Conclusion
Quorum sensing plays a main role in controlling
diversity of microbial cell activities, biofilm
formation, virulence human health ,,agriculture
,marine, commercial manufacture, and transfort
system.
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YOU