Introduction to Bacteria

Introduction to Bacteria

L.Os

• Describe the basic structure of bacteria
• Describe basic functions of different structures
• Describe and apply basic concepts of taxonomy

Bacteria are small, rate at which nutrients and waste enter and leave the cell = inversly proportional to cell size
Therefore:

• Higher growth rates
• Faster evolution
• Adapt and exploit new environments

Basic Structure of Prokaryotic cell

• Cell wall = petidoglycan
  + flagella, pili etc. Provide ridgidity
• Cell/Plasma membrane = phospholipid bilayer
  Regulates passage in/out bacteria via pore and channels
• Cytoplasm
  DNA, RNA, Enzymes, Regulatory proteins, Protein synthesis machinery
• Nuclear region
  No true nucleus 

Cell Wall
DIvides bacteria into 2 main groups
- Gram -- = doesn't tuen purple in crystal violet. then use safranin/carbol fuchsin = Pink stained
- Gram + = turn purple in crystal violet

CW = largely Peptidoglycan
- Polysaccharide backbone + NAG and NAM with cross-linked peptides (short-chain Animo Acids)
- These AAs provide rigid structure
- Enzymes involved in forming crosslinks = targets of antibiotics e.g penecillin

(Comparison in other resource)
Basically, Gram -- has an outer membrane whereas Gram+ don't.

Gram -- Outer Cell Membrane
= permeable lipid bilayer containing phospholipids and LPS (lipopolysaccharide)
Main role as protection, in…