BACTERIAL MORPHOLOGY CONTD...

B) STRUCTURE INTERNAL TO CELL WALL;

1) Cytoplasmic membrane:  It is a thick structure( 8 nm)  that separates the cytoplasm from outer membrane. It is composed of phospholipid & protein. Phospholipid forms the bi layer in which protein( integral & peripheral) are held.

Functions:
  • It acts as permeability barrier & prevents the leakage of cytoplasmic constituents  into or out of the cell. 
  • Specific proteins in membrane facilitates passage of small molecules across the membrane.
  • It contains several enzymes involved in respiratory metabolism & in synthesis of cell wall & capsular components. 
Note: Polymyxins  makes holes on cytoplasmic membrane while detergents & alcohol dissolves the bi-layers.



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