About Bacteriophage as for replacing antibiotic

1. Bacteriophage
Replacing Antibiotic
Therapy
Uttam Belbase

2. Antibiotic (anti-bacterial)
A type of antimicrobial drug .
Used in the treatment and
prevention of bacterial
infections .
Kill or inhibit the growth of
bacteria .

3. Antibiotics Discovery
In 1928 - Alexander Fleming discovered first antibiotic
penicillin. Penicillin was the first antibiotic to be
discovered. Penicillin is derived from a substance
produced from molds of the Penicillium fungi.
Penicillin works by disrupting bacterial cell wall
assembly processes and interfering with bacterial
reproduction. Today, other penicillin-related
antibiotics including ampicillin,
amoxicillin, methicillin, and flucloxacillin are used to
treat a variety of infections.

4. Antibiotics work?
# A Bactericidal antibiotic kills the bacteria generally by
either interfering with the formation of the bacterium's
cell wall or its cell contents. Penicillin, daptomycin,
fluoroquinolones, metronidazole, nitrofurantoin and
co-trimoxazole are some example of Bactericidal
antibiotics.
# A Bacteriostatic antibiotic stops bacteria from
multiplying by interfering with bacterial protein
production, DNA replication, or other aspects of
bacterial cellular metabolism. Some Bacteriostatic
antibiotics are tetracyclines, sulphonamides,
spectinomycin, trimethoprim, chloramphenicol,
macrolides and lincosamides.

5. Mechanism of Antibiotic Resistance
*Drug inactivation due to enzyme modification.
*Alternation of target site.
*Alternation of metabolic pathway.
*Reduce drug accumulation.
*Bio-film formation.
*Restricted penetration of antibiotics.
*Adaptive response.
*Quorum sensing.
*Genetic alternation to persister cell.
*Nutritent limitations altered microenvironment.

9. What are alternative to antibiotics?
#Bacteriophages .
#Probiotics & Prebiotics.
#Bacteriocins.
#Phytochemicals & Heavy metals.
#Host derived antimicrobials.
#Acidifying agents.
#Small interfering RNAs.
#Naturally occuring antibacterial lytic enzymes.
#Recombinant & Hyperimmune therapeutic
antibodies.
#Immune enhancers & Cytokines.

10. Bacteriophage

11. Discovery / History of
Bacteriophage
# In 1896 Ernest hanbury hankin, British
bacteriologist found bacteriophage in ganges
& yamuna rivers in india. They pass theough a
very fine porcealin filter & was heat labile.
Presence of marked antibacterial activity
against vibro cholerae, which he observed in
the waters.
# In 1915 - Frederick twort & In 1917 Felix
d’herellein both scientists discovered
bacteriophage independently.

12. Phages ?
# Viruses that infect bacteria ,invading
bacterial cells by injecting genetic
material.
#Host specific infections.
#Infect & replicate in bacterial host cells.
#Lifecycle - Lytic & Lysogenic cycle.
#DNA phage - ssDNA & dsDNA
#RNA Phage - ssRNA & dsRNA.

13. Phage location ?
#Human and animal intestine.
#Bunning water.
#Soil.
#Effluent outlets.
#Sewage from corpses.
#Most common & diverse entities
in the biosphere.

14. Classification/ Taxonomy
By International Committee on
Taxonomy of Viruses(ICTV):
3-order,
73-families,
9-subfamilies,
287-genera &
1938 virus species.

15. Type of phages ?
# λphage – Lysogen.
#T1phage.
#T2 phage.
#T4 phage.
#T7phage.
#M13 phage.
#MS2 phage.
#P1 Phage.
#Enterobacteria Phage P2.

16. Bacteriophages as an intervention?
#Felix d’Herelle explored using phage solutions to treat
dysentery in humans.
#During World war II phage solutions were supplied to
soviet union & russian soldiers, where it was used to
prevent diarrhea caused by E.coli.
#Republic of Georgia has been using phage therapy
since the 1940s.
#Present phage therapy for humans is available at the
phage therapy centre in the Republic of Georgia & in
poland.
#In 2006,US FDA approved Listeria phage solution for
using in ready-to-eat meat & poultry.
#In 2011,US FDA approved Ecoli phage for using on
food.

17. Lifecycle: Lytic cycle Vs Lysogenic Cycle

19. Phage Therapy
# Therapeutic use of bacteriophages to treat
pathogenic bacterial infections.
# Biocontrol.
#Lysin therapy & Prophylaxis.
#Ultimate Goal – Sufficent bacterial killing to
prevent or alleviate infection & clinical Symptoms.

20. Why Phage Therapy?
Issue Phage Antibiotics
Fate of the “drug” molecule Exponential growth in
numbers, so that the
“drug” makes more of
itself at the site of
infection, where it is
needed.
Metabolic destruction of the
molecule, as it works
Concentration of the “drug”
required to kill a given
bacterium
One phage particle is
sufficient to kill a given
bacterium.
Numerous molecules of the
antibiotic are needed to kill a
given bacterium.

21. Issue Phage Antibiotics
Ability to overcome bacterial
resistance
Phages are “living” organisms
that undergo mutations,
some of which can overcome
bacterial mutations.
Antibiotics are fixed & cannot
adapt to a bacterial mutation.
Bacteria that have resisted
them can pass along the
resistance trait within and
between species
Spread of bacterial resistance Phages tend not to cross
species boundaries. Thus
even though the targeted
bacterial species may become
resistant to the phage, it is
unlikely that other species
will.
The antibiotics in use tend to
be broad spectrum, thereby
provoking resistance in
several species and genera of
bacteria.
Specificity Very specific. Affect only the
targeted bacterial species so
secondary infections doesn't
occur.
Antibiotics target both
pathogenic microorganisms
and normal microflora. Thus
the the microbial balance in
the patient is affected, which
may lead to serious secondary

22. USES OF PHAGE THERAPY
# Destruction of biofilm .
# Enzymes produced by phages used as enzybiotics.
# In food industry for control of bacterial loads on
food & to control the presence of biofilms in the
food processing environment.
# Candidate for co-therapy with antibiotics –
prevent the emergence of bacterial resistance to
antibiotic.
# PhagoBioDerm - used to treat recurrent leg ulcer
and infections in burn victims.
# Future application – Phage Particles as Vaccine
Delivery Vehicles

23. Large scale production & purification
strategy.
1st Production of bacteria.
2nd Inoculating the bacteriophage.
3rd Separation of lysate by filteration.
4th Primary purification(ATPE yamamoto et.al).
5th Secondary purification(size exclusion-
chromatographic focussing).
6th Final(freeze drying).

24. Advantages of phage
#Ubiquitous in nature,
# Highly active & Specific.
#Genetically modified or amenable.
#Versatile use along food chain.
#Tools for detecting pathogenesis.
#Source of potent antimicrobials.
#Effective against most resistant bacteria.
#Low cost for preparation (Cheap).
#Intelligent drug.
#Effective even to mature form of biofilm.

25. Prerequisites of bacteriophage therapy
#Up-to now internationally not accepted
phage therapy as best method.
#Should not be attempted before the biology
of the therapeutic phage is well understood.
#Should meet all the safety requirements.
#Phage receptor should be known.
#Efficiency of phage therapy should be tested
in animal.
#Purity of Bacteriophages suspension should
be done before administration.

26. Conclusion
The need for alternatives to antibiotics such as
phage therapy is essential due to increase of
resistance of bacteria towards antibiotics. Thus
revisiting the exploitation & research on
therapeutic property of phages are needed. Though
this approach has been neglected by the western
world in the past but due to antibiotic resistance, it
has been recently stressed by the WHO. Thus
knowing the history of this therapy helps us to
understand and develop it further for future use.

27. Thank You