2. Classification
• From a common ancestor, 3 domains developed.
These include Eukarya, Archaea, and Bacteria. From
each of these domains, there are different phylum.
 The phylum under Eukarya is the Eukaryotes.
 The phylums under Archaea include Korarchaotes,
Euryarchaeotes, Crenarchaeotes, and Nanoarchaeotes.
 The phylums under domain bacteria include
Proteobacteria, Chlamydias, Spirochetes,
Cyanobacteria, and Gram- positive bacteria.

4. • Korarchaeum cryptofilum
 These archaea have only been found in high
temperature hydrothermal environments, particularly
hot springs.
 They have only been found in very small numbers.
 Research on the gene sequences of these organisms
indicates that they are very closely related, although
still unique, from Crenarchaeotes and
Euryarchaeotes.

5. • Methanococcus jannischii
 This is a thermophilic methanogenic archaea,
meaning that it thrives at high temperatures and
produces methane.
 This archaea was the first to have its complete genome
sequenced.
 When the genome was sequenced, it became evident
that it was very unique and helped with the argument
that there are 3 domains instead of 2.

6. • Sulfolobus solfataricus
 The origins for DNA replication for this organism were
identified in 2004.
 The results showed that the organism contained 2
origins in its genome. This was the first prokaryote to
have evidence of more than one origin for its DNA.
 Today, it is used to study DNA replication in archaea.

7. • Nanoarchaeum equitans
 This organism was discovered in 2002 and is
considered a thermophile.
 It must be in contact with other cells to survive.
 Scientists still debate whether or not it is a living
organism.
 However, if it proves to be, it would be the smallest
living organism on the planet, whose cells have a
diameter of 400 nanometers and have a genome of
only 490, 885 nucleotides long.

9. • Escherichia coli
 This organism is often abbreviated E. Coli.
 It is a rod shaped bacteria that is found in the lower
intestine of warm blooded animals.
 Although most E. Coli is harmless, certain strands of it
can be dangerous and cause food poisoning

10. • Salmonella enterica
 This organism is a rod shaped, flagellated bacteria.
 It is a facultative anaerobe, meaning that it can live
with or without oxygen.
 It is known to infect cattle and poultry, and then when
people eat the infected meat, they develop a condition
called salmonellosis.
 Raw eggs can also contain the bacteria, and so this is
why people are often cautioned before they consume
foods containing raw egg.

11. • Chlamydia trachomatis
 This is an obligate intracellular pathogen, meaning
that it can grow and reproduce in its host’s cell.
 It causes complications such as urethritis, proctitis,
trachoma, and infertility.
 Trachoma is a major condition associated with this
bacteria, which is an infection of the eye.

12. • Chlamydia muridarum
 This was originally considered to be chlamydia
trachomatis.
 However, the difference is that chlamydia trachomatis
affects only humans, while chlamydia muridarum
affects the family Muridae.
 This family includes species such as mice and
hamsters.

13. • Borrelia burgdorferi
 This bacteria mainly exists in North America.
However, it has appeared, although more rarely, in
Europe.
 It is the cause of Lyme Disease, which is carried by
ticks.
 Borrelia burgdorferi is one of the few pathogens that
can survive without iron.
 It was the 3rd microbial genome ever sequenced.

14. • Treponema pallidum
 This bacteria is associated with the diseases of syphilis,
bejel, pinta, and yaws.
 They are gram- negative, meaning that they have an
outer membrane, but cannot be seen on a Gram
stained smear because they are too skinny to be seen
under a light microscope.

15. • Prochlorococcus marinus
 They are the smallest known photosynthetic
organisms.
 In comparing a marine cyanobacteria with eukaryotic
algae, the difference in numbers of genes is
astounding. While eukaryotic algae has more than
10,000 genes, this species contains only roughly 2,000.
 It is estimated that 20% of the Earth’s oxygen comes
from these creatures.
 They are also essential to food chains in the ocean.

16. • Prochloron didemni
 This is a unicellular photosynthetic organism found
mainly in coral reefs.
 It is theorized in the endosymbiotic theory that these
organisms are precursors to the photosynthetic parts
of eukaryotes, although this is still highly debated.

17. • Actinomyces israelii
 This is known as the “most misdiagnosed disease”
because doctors often do not catch it until the later
stages.
 It affects the vagina, colon and mouth.
 One of the most common diseases associated with the
bacteria is Oral- cervicofacial disease, in which the
infected person has a lumpy, but painless jaw.
 Another common disease is thoracic disease, although
this is commonly misdiagnosed as a neoplasm.

18. • Streptomyces achromogenes
 This bacteria is grown under conditions of 28 degrees
Celsius in yeast and malt extract with glucose.
 It was the original source of a drug intended to help
treat pancreatic cancer called, “streptozoticus”

19. • Streptomyces griseus
 This bacteria is most commonly found in the soil.
 It is a well-known producer of antibiotics, and this is
the first bacterium to ever produce an antibiotic.
 It has also been recently discovered as an efficient
water purifier.