Archaebacteria and Eubacteria

Archaebacteria and Eubacteria:-

1. Alternative Names:-

Archaebacteria:- Archaebacteria are called ancient bacteria.

Eubacteria:- Eubacteria are called true bacteria.

2. Size:-

Archaebacteria:- Individual archaebacterium is 0.1-15 μm in diameter.

Eubacteria:- Individual eubacterium is 0.5-5 μm in diameter.

3. Shape:-

Archaebacteria:- Archaebacteria are spheres, rods, plates, spiral, flat or square-shaped.

Eubacteria:- Eubacteria are cocci, bacilli,  vibrio, rods, filaments or spirochetes in shape.

4. Complexity:-

Archaebacteria:- Archaebacteria are simple in their organization.

Eubacteria:- Eubacteria are more complex than archaebacteria.

5. Habitat:-

Archaebacteria:- Archaebacteria are found in extreme environments.

Eubacteria:- Eubacteria are found everywhere on earth.

6. Cell Wall:-

Archaebacteria:- Cell wall is composed of pseudo peptidoglycans.

Eubacteria:- Cell wall is composed of peptidoglycans with muramic acid.

7. Membrane Lipids:-

Archaebacteria:- Membrane lipids of archaebacteria is ether-linked, branched, aliphatic chains, containing D-glycerol phosphate.

Eubacteria:- Membrane lipids of eubacteria are ester-linked, straight chains of fatty acids, containing L-glycerol phosphates.

8. RNA Polymerase:-

Archaebacteria:- RNA polymerase of archaebacteria consists of a complex subunit pattern, which is similar to eukaryotic RNA polymerase.

Eubacteria:- RNA polymerase of eubacteria consists of a simple subunit pattern.

9. Transfer RNA:-

Archaebacteria:- No thymine is present in the TψC arm of the tRNA, carrying methionine. 

Eubacteria:- Thymine is present in most of the tRNA, carrying N-formyl methionine.

10. Introns:-

Archaebacteria:- Introns are present in archaebacteria.

Eubacteria:- Introns are absent in eubacteria.

11. Growth and Reproduction:-

Archaebacteria:- Asexual reproduction methods like binary fission, budding and fragmentation are used by archaebacteria during their reproduction.

Eubacteria:- Other than binary fission, budding and fragmentation, eubacteria are capable of producing spores in order to remain dormant during unfavorable conditions.

12. Glycolysis/Kreb’s cycle:-

Archaebacteria:- Archaebacteria exhibit neither glycolysis nor Kreb’s cycle.

Eubacteria:- Eubacteria exhibit both glycolysis and Kreb’s cycle.

13. Types:-

Archaebacteria:- Archaebacteria are three types: methanogens, halophiles and thermophiles.

Eubacteria:- Eubacteria are two types: gram positive and gram negative.

14. Examples:-

Archaebacteria:- Halobacterium, Lokiarchaeum, Thermoproteus, Pyrobaculum, Thermoplasma and Ferroplasma are the examples of archaebacteria.  

Eubacteria:- Mycobacteria, Bacillus, Sporohalobacter, Clostridium and Anaerobacter are the examples of eubacteria.