This is all about the kingdom Archaebacteria.

1. KINGDOM
OF
ARCHAEBACTERIA

2. ARCHAEBACTERIA?
• The oldest organism living on Earth. They are
unicellular prokaryotes microbes without cell nucleus
and any other membrane-bound organelles in their
cells and belong to the kingdom, Archaea. They were
first discovered in 1977 by Carl Woose and George E.
Fox and classified as bacteria. Most archaebacteria
appear like bacteria, when observed under the
microscope. However, they are quite different from
bacteria and eukaryotes.

3. WHERE CAN WE FIND THEM?
•Archaebacterial are found in very harsh
conditions such as in the volcanic vents
or at the bottom of the sea. They can
easily survive in such extreme
environment as sea vents releasing
sulfide-rich gases, hot springs, or boiling
mud around volcanoes.

6. WAIT, THERE’S MORE!
•Under the kingdom
Archaea, archebacteria
are classified into the
following phyla

7. • Phylum Euryaarchaeota: This is the most studied
division of archaea, and mostly includes methanogens
and halophiles
• Phylum Crenarchaeota: It includes thermophiles,
hyperthermophiles and thermoacidophiles. These
archebacteria are mostly found in the marine
environment.
• Phylum Korarchaeota: This division consists of
hyperthermophiles found in high temperature
hydrothermal environment.

8. • Phylum Thaumarchaeota: This phylum includes
ammonia- oxidizing archaea, as well as those with
unknown energy metablolism.
• Phylum Nanoarchaeota: This phylum has a single
representative member named Nanoarchaeum
equitans. This unusual archebacterium is an
obligate symbiont of another archaea belonging to
the genus Ignicoccus.

9. WHAT ARE THE IMPORTANCE OF THIS?
Archaebacteria are important, almost indispensable, for the following reasons:
• They have phylogenetic importance that helps in
studying their homology and establish their
phylogeny.
• Their ability to tolerate extreme conditions helps
researchers learn about the climatic conditions,
environment and their survival on ancient earth.

10. • Methanogens can grow in biogas fermentors and
decompose cow dung into methane gas as a by-product.
Thus, they are used for production of domestic gas for
cooking.
• Organisms like Methanobacterium ruminantium are present
in the guts of ruminating animals, helping them digest the
cellulose.
• Poor ores of molybdenum are microbial leached
using Sulfolobus.
• Archaebacteria are also used to synthesize thermophilic
enzymes, restriction enzymes and are also used as
biosensors.

11. • Archaebacteria have an important role in many
chemical cycles, like carbon cycle, nitrogen cycle,
sulfur cycle, etc.
• Due to their extremophilic nature,
archaebacteria have proven to be of great help
in the field of Bioechnology, by helping in the
production of enzymes that work at very high
temperatures, as well as in the production of
some antibiotics.

12. • The characteristics of
Archaebacteria kingdom prove that life can
exist anywhere, under any condition. The
mere existence of these extremophiles
gives us hope. Maybe we will discover
something on the other planets yet!