Biotechnology Applications
1.Quorum sensing
Definition:- type of decision-making process used by groups of creatures to coordinate behavior.
- signaling molecule that affect a reaction in a population of cells that is distinct from the manner in which the cells would behave individually.
-Examples:
1-Bacteriae.g. vibrio fischeri
-use quorum sensing to coordinate their gene expression according to the local density of their population.
2-social insects e.g. honey bees and ants
-use quorum sensing to make decisions about where to nest.
Mainly through (dancing number, waiting periods)
1)At low cell density (i.e. small no. of bacteria):
-low conc. Of activator molecules >>>>>>> No Quorum sensing occur (NO bioluminescence).
2) At High cell density (i.e. high no. of bacteria):
-accumulation of activator molecules (inducers) >>>>>>>> action on sp. Receptors >>>>> inductionof transcription of luciferase enzyme genes>>>>>> bioluminescence(emission of blue-green light).
Mechanism:
-Organisms that use quorum sensing are able to constantly produce certain signaling molecules (inducers).
-At sufficient cell density, These molecules are specifically interacting with corresponding receptors.
-when the inducer binds the receptor; it activates transcription of certain genes.
-Inducer(signaling molecule) + receptor(in bacteria) ----------->(At high no. of cells) gene transcription
E.g. luciferse enzyme in (V.fischeri)
-Importance of Quorum sensing to bacteria
1-Regulation of cell division e.g. Escherichia coli .
2-Regulation of cell aggregation and formation of biofilms .
3-Regulation of expression of virulence factors, immune system invasion, resistance to antibiotics .
e.g. Pseudomonas aeruginosa& Staphylococcus aureus .
Applications:
A.Medicinal applications:
-Controlof pathogenic bacteria(e.g. Staph. aureus& Pseudomonas aeuroginosa) through controlling their ability to form biofilm (cell aggregation) or expressionof their virulence factors.
e.g. Garlic inhibition of pulmonary pseudomonas infections.
e.g. inhibition of biofilm formation within catheters or artificial valves.
B.Industrial applications:
1.Inhibitionof biofilm formation in the oil pipes.
2.Improvement of the yield of production of valuable bio-products such as proteins or antibiotics(through the regulation of gene expression) .
c. Environmental applications:
1. Induction of the biofilm forming ability to enhance the biodegradation capacity for removal of xenobiotics and other toxic pollutants.
2. Pest control through inhibition of multiplication and nest formation through misleading signals.
2-Nanotechnology
-is the study of the controlof matter on an atomicand molecular scale.-There are 2 mainly approaches used in nanotechnology:
1-Bottom-up approaches: Arrange smaller (nano-) components into complex structure
2-Top-down approaches: Convert lager materials to smaller (nano-) devices
-Materials reduced to the nano-scale can show different properties(mechanical, electrical, optical, etc.) compared to what they exhibit on a macro scale.
-Examples:
-opaque substances become transparent (e.g. copper).
-stable materials turn combustible(e.g. aluminum).
-A material such as gold, which is chemically inert at normal scales, can serve as a potent chemical catalyst at nanoscales.
Bionanotechnology=Nanobiotechnology
Applications of bionanotechnology :
1. DNA nanotechnology: based on using base pairing to construct well defined structures of DNA (e.g. genes).