While many prokaryotes cause human diseases like tuberculosis and diarrhea, prokaryotes also have beneficial uses. They play an important role in bioremediation by breaking down pollutants and cleaning up oil spills. Additionally, genetically engineered prokaryotes can now produce useful compounds like vitamins and antibiotics. However, overuse of antibiotics has led to increased antibiotic resistance in prokaryotes due to their rapid reproduction.

2.  Intro
 Pathogenic Prokaryotes
 Prokaryotes in research and technology

3.  Although one may think the amount of
harmful prokaryotes is higher than the
amount beneficial prokaryotes, it is
actually the opposite.

4.  Prokaryotes cause about half of all
human diseases
 There are many diseases caused by
prokaryotes
› Tuberculosis
› Diarrheal diseases
› Lyme disease (caused by parasites)

5. Lyme disease

6.  Illness producing poisons are classified as
exotoxins and endotoxins
 Exotoxins are proteins secreted by
eukaryotes
› Can produce a disease even if the prokaryotes
that manufacture them are not present
 Endotoxins are lipopolysaccharide
components of the outer membrane of
gram-negative bacteria
› Only released when the bacteria die and their
cell walls break down

7.  So how have humans slowed the
reproduction of prokaryotic diseases?
› Antibiotics
› Better sanitation habits

8.  Improvements in sanitation and
antibiotics has reduced the threat of
pathogenic prokaryotes.
 However, resistance to the antibiotics
are becoming more likely because of
the fast reproduction of prokaryotes.

9.  Horizontal gene transfer turns normally
harmless prokaryotes to fatal pathogens.
 E.Coli for example is harmless, but strains
that cause bloody diarrhea emerged.
 O157:H7 causes 75,000 infections per
year often from contaminated beef.
› It was compared to K-12 and 1,387 out of
5,416 genes have no counterpart in K-12.

10.  Prokaryotes are the principal agents in
bioremediation.
› Bioremediation is the use of organisms to
remove pollutants from soil, air, or water.
› Bioremediation also breaks down
radioactive waste and cleans up oils
spills.

11. Figure 27.17

12.  Prokaryotes are used in mining.
 Through genetic engineering, humans can
now modify prokaryotes to produce
vitamins, antibiotics, and hormones.
 Craig Venter – one of the leaders of the
Human Genome Project.