Microorganisms are small organisms invisible to the naked eye because of their extremely small size.They are grouped into various groups like Bacteria, fungi, algae, protozoa and viruses. Many of these organisms are useful to human and nature while some are harmful and even cause diseases.

1. Beneficial Microbes: Health or Hazard?
By Praneeth Silva
Department of Zoology
University of Sri Jayewardenepura

2. Content
(1) Introduction
(2) Beneficial Microbes: Used in Medicine
(5) Beneficial Microbes: Used in Agriculture
(4) Beneficial Microbes: Used in Food industry(Probiotics)
(6) Discussion
(7) References
(3) Pharmacy in the gut

3. Introduction
Microbes
Classification
Beneficial Microbes
Health Hazard
Naturally
Human Involvement

4. Beneficial Microbes: Used in
Medicine
Synthesis of Human Insulin
Synthesis of GH
Synthesis of Vaccines
Synthesis of
Antibiotics

5. Synthesis of Human
Insulin
What's?
Importance?
Bovine
Porcine
Insulin?
Complications
ContaminationHypoglycemia

6. Synthesis of GH
What's?
Importance?
GH?GH?
Limitation
s
Bovine
Porcine
New
approaches

7. What's?
Disease causing
microbes
resembles
Weakened
Killed
Toxins
Types
Strategies
Reduce the risk of illness
Inactivated
Attenuated
Toxoid
Subunit
Conjugate
DNA
Benefits
Hazards
Vaccines Content
Surface
Proteins

8. Inactivated Vaccines
Made from microorganisms
Bacteria Virus Other
Physically
Chemically
killed
Immune response may not be long lived
Several doses of inactivated whole-cell
vaccines may be required.
may not always induce an immune response

9. Adverse reactions associated with inactivated whole-
cell vaccines

10. LAV Vaccines
Disease-causing pathogensWeakened
No Mild
Disease
capable of replicating
within host cells
Continual antigenic
stimulation
Excellent immune
response
Mycobacterium bovis
Tetravalent vaccine

12. Toxoid Vaccines
Toxin produced by certain bacteria
Harmless
Antigen
Cannot cause the
disease
No possibility of
reversion to virulence

13. DNA Vaccines Infectious agent’s DNA
Created from
Under development
Instantly attacked to the
natural pathogens
Potential
advantages
Easy to produce
Easy to store Live for a long time

14. DNA Vaccines
(Hazardous)
Uncontrolled expression
Germ line Transmission
PCR studies
Vaccinated fetuses Gonads of the fetuses Offspring of these fetuses
Non
replicating
plasmids
Narrow host
range
replication
regions

15. Antibiotics
Chemical substances ,that can inhibit the
growth of microorganisms
Fermentation process
Used in many forms
Eye
Skin surface Swallowed
Injected
Chemically differ

16. Antibiotics
action
Weaken the cell walls Damaging the cell membrane
Effect to
metabolism
Tetracycline Erythromycin
Streptomyces
Antibiotic
Roseoflavix
Hyphae formation
Anti fungal compounds
Anti bacterial
compounds

17. Streptomyces
Chloramphenicol-S.roseosphorus
Daptomycin- S.roseosphor
Fosfomycin- S.fradiae
Lincomycin- S.lincolnencis
Neomycin- S.fradidae
Streptomycin- S.griseus
Tetracycline- S.rimosus
Anti bacterial agents/ compounds
Nystatin- S.neursei Anphotericin B- S.nodosus
Natamycin- S.natalensis
Anti fungal agents/ compounds

18. Pharmacy in the gut
Microbial “Finger print”
10 *11/12
(cells/g)
150 times larger than
the human genome
Dominant phyla
Fermicutes
Ex-(Lactobacilli)
Bacteriodes
Actinobacteria
Ex-(Bifidobacterium)
Proteobacteria
Metabolic
Trophic
Protective

19. Translocation of Bacteria
The passage of viable/ dead bacteria from GI
tract,through epithelial mucosa
Translocation of
endotoxins
Dysfunction of the
Gut- mucosal
barrier
Burn injury
Intestinal obstruction
Acute liver failure
Haemorrhagic shock
Distribute
throughout
the body
Shock
Multi system
organ failure Death of the
organism

20. Colon cancer
Dietary factors + Genetic factors
Rich
Fat Meat
Bacteroides sp..
Clostridium sp.
Carcinogens Cocarcinogens Procarcinogens
N-nitroso compounds
Damage to DNA in colon cells
(Promotors of colon cancer)
Colonic cancers

21. Probiotics
Beneficial
microbes
Prevention and treatment of specific
pathogenic conditions
When they are ingested
Lactobacillus sp. Bifidobacterium sp. E. coli Streptococcus sp.
Enterococcus sp. Bacillus sp.
Prevent and treat to GI
disorders
Competition for limited
food sources
epithelial and mucosal
adherence
Epithelial invasion and
production of antimicrobisl
substsnces
Inhibit

22. Intestinal disorders
Treated
Probiotics
Antibiotic-induced
diarrheal disease
Infectious diarrhea
Travelers disease
Rotavirus diarrheaHIV/AIDS diarrhea
Lactose intolerance

23. Lactose intolerance
Deficiency of beta- galactosidase
Lactose fermentation
Bloating
Diarrhea
Nausea
Lactose positive strains
Lactobacillus sp.
Bifidobacterium sp.
Streptococcus sp.
Digestibility of lactose
present products
Release Lactase

24. Hepatic encephalopathy
Neurologic disorder
Caused by
Blood NH3
Urea
Bacterial
ureases
Intestine
Healthy individuals Patients with liver failure
Detoxified by the liver Not detoxified by the liver
Patients
Treated
with
Neomycin+L.acidophillus
Decreased urease activity

25. Mechanism of action
(Probiotics)
Protect the host from
intestinal disorders
Production of
inhibitory
substances
Blocking of
adhesion sites
Competition
for nutrients
Degradation of
the toxin
receptor

26. Beneficial microbes
used in Agriculture
Bacillus thuringiencis Insect resistant plants
Naturally occurring
Soil bacteria
Produced a toxin
Reduction of
insecticide
application
Recombinant DNA
technology

27. Adverse effect of Bt cotton
Effect to natural
enemies
Dipterans
Coleopterans
Lepidopteron
Pollen of Bt corn
blown
Milk weed
leaves
Fed by Monarch
caterpillars

28. Adverse effect of Bt crops
Researchers did some experiment
Using rats
found
Bt corn was fed to rats
Dmaged
Liver
Kidney Small intestine
Cause Changes
Heart
Adrenal
Spleen
Blood cells

29. Discussion
Microbes
Beneficial Non- Beneficial
Health
Hazardous
Most
Hazardous
Natural
enviroment
But
Beneficial
microbes
Human
involvement
Technology
Extract the
benefits
Beneficial
microbes
Hazardous

30. References
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Gilbert, H.J., 2004. Assessing the survival of transgenic plant DNA in the human gastrointestinal
tract. Nature biotechnology, 22(2), p.204.
(2) Linares, D.M., Ross, P. and Stanton, C., 2016. Beneficial microbes: the pharmacy in the gut.
Bioengineered, 7(1), pp.11-20.
(3) Guarner, F. and Malagelada, J.R., 2003. Gut flora in health and disease. The Lancet,
361(9356), pp.512-519.
(4) Hooper, L.V., Bry, L., Falk, P.G. and Gordon, J.I., 1998. Host–microbial symbiosis in the
mammalian intestine: exploring an internal ecosystem. Bioessays, 20(4), pp.336-343.

31. (5) Nagpal, R., Behare, P.V., Kumar, M., Mohania, D., Yadav, M., Jain, S., Menon, S., Parkash,
O., Marotta, F., Minelli, E. and Henry, C.J.K., 2012. Milk, milk products, and disease free
health: an updated overview. Critical Reviews in Food Science and Nutrition, 52(4), pp.321-
333.
(6) Parvez, S., Malik, K.A., Ah Kang, S. and Kim, H.Y., 2006. Probiotics and their fermented
food products are beneficial for health. Journal of applied microbiology, 100(6), pp.1171-
1185.
(7) Drisko, J.A., Giles, C.K. and Bischoff, B.J., 2003. Probiotics in health maintenance and
disease prevention. Alternative medicine review, 8(2), pp.143-155.