viral and bacterial genome

1. BY
NABAA AL WAZEN
BACTERIAL & VIRAL
GENOME

3. Structure
 Bacteria are prokaryotes, lacking well-defined
nuclei and membrane-bound organelles, and with
chromosomes composed of a single closed DNA
circle.
 They come in many shapes and sizes, from
minute spheres, cylinders and spiral threads, to
flagellated rods, and filamentous chains. They are
found practically everywhere on Earth and live in
some of the most unusual places.

4.  Evidence shows that bacteria were in existence
as long as 3.5 billion years ago, making them one
of the oldest living organisms on the Earth.
 Even older than the bacteria are the archeans
,tiny prokaryotic organisms that live only in
extreme environments: boiling water, super-salty
pools, sulfur-spewing volcanic vents, acidic water.

6. Bacterial genome

7.  Bacterial genomes are generally smaller and less
variant in size among species when compared
with genomes of animals and single cell
eukaryotes.

8. Plasmids
 a genetic structure in a cell that can replicate
independently of the chromosomes, typically a
small circular DNA strand in the cytoplasm of a
bacterium or protozoan.
 They are most commonly found as small circular,
double-stranded DNA molecules in bacteria;
however, plasmids are sometimes present in
archaea and eukaryotic organisms.
 In nature, plasmids often carry genes that may
benefit the survival of the organism,

10.  A virus is a biological agent that reproduces
inside the cells of living hosts.
 When infected by a virus, a host cell is forced to
produce thousands of identical copies of the
original virus at an extraordinary rate.

12. Retrovirus
 A retrovirus is a single-stranded positive-sense
RNA virus with a DNA intermediate and, as an
obligate parasite, targets a host cell.
 Once inside the host cell cytoplasm, the virus
uses its own reverse transcriptase enzyme to
produce DNA from its RNA genome, the reverse
of the usual pattern, thus retro (backwards).
 The new DNA is then incorporated into the host
cell genome by an integrase enzyme, at which
point the retroviral DNA is referred to as a
provirus.

13.  The host cell then treats the viral DNA as part of
its own genome, transcribing and translating the
viral genes along with the cell's own genes,
producing the proteins required to assemble new
copies of the virus.

16.  https://micro.magnet.fsu.edu/cells/bacteriacell.ht
ml
 https://courses.lumenlearning.com/microbiology/c
hapter/the-viral-life-cycle/
 Wikipeidia

17. Thank you