Extraction of Genomic DNA from
Bacterial Cells using CTAB Method.
Aim: To extract high-quality genomic DNA from bacterial cells using the
CTAB (Cetyltrimethylammonium Bromide) method.
Principle: The CTAB method for DNA extraction uses a cationic detergent
(CTAB) to lyse bacterial cell walls and membranes by disrupting lipid bilayers.
CTAB binds to polysaccharides and proteins, precipitating them out of the
solution, thereby facilitating the isolation of pure DNA.
The process involves:
Cell lysis
Removal of proteins and other contaminants through phenol-chloroform
extraction
Precipitation of DNA using isopropanol.
Fig 1.1: DNA found in the aqueous
medium.
Reagents and Their Functions:
CTAB Extraction Buffer
CTAB (Cetyltrimethylammonium Bromide): Lysing agent that disrupts
bacterial membranes, binds to polysaccharides and proteins, and purifies
DNA.
NaCl (Sodium Chloride): Stabilizes DNA and helps in precipitation of
polysaccharides and proteins by neutralizing their charges.
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Bacterial Cells using CTAB Method.
Aim: To extract high-quality genomic DNA from bacterial cells using the
CTAB (Cetyltrimethylammonium Bromide) method.
Principle: The CTAB method for DNA extraction uses a cationic detergent
(CTAB) to lyse bacterial cell walls and membranes by disrupting lipid bilayers.
CTAB binds to polysaccharides and proteins, precipitating them out of the
solution, thereby facilitating the isolation of pure DNA.
The process involves:
Cell lysis
Removal of proteins and other contaminants through phenol-chloroform
extraction
Precipitation of DNA using isopropanol.
Fig 1.1: DNA found in the aqueous
medium.
Reagents and Their Functions:
CTAB Extraction Buffer
CTAB (Cetyltrimethylammonium Bromide): Lysing agent that disrupts
bacterial membranes, binds to polysaccharides and proteins, and purifies
DNA.
NaCl (Sodium Chloride): Stabilizes DNA and helps in precipitation of
polysaccharides and proteins by neutralizing their charges.
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