Structure and function of the Bacterial Cell

Morphologies of prokaryotic cells

• coccus

• rod

• spirillum

• spirochete

cell size

• prokaryotes: 0.2 um - 600+ um

• eukaryotes: 5 - 100 um

Gram positive cell envelopes

• thick peptidoglycan layer

• 1 cytoplasmic membrane

Gram negative cell envelopes

• thin peptidoglycan layer

• cytoplasmic membrane

• outer membrane

what does the cytoplasmic membrane do

• surrounds cytoplasm

• separates it from environment

• selective permeability

Membrane structure of Bacteria and Archaea

• Bacteria: phospholipid Bilayer

• Archaea: phospholipid Monolayer

Functions of the cytoplasmic membrane

• selective permeability

• protein anchor

• energy conservation

where does energy come from in bacteria

the proton motive force

where does energy come from in Archaea

ATP

simple transport

ABC transport

group translocation