This presentation mentions a brief alternative for antibiotics

1. Alternatives for conventional
Antibiotics
BY MUSTAFA MASOOD

2. contents
Introduction
Bacteriophage Therapy
Anti-quorum Sensing
Bacteriocin
Probiotic
Predatory bacteria ‘living antibiotic’
Combining Antimicrobial Peptides with Nanotechnology
Nanorobots

3. Introduction
The golden age of antibiotics
 In 1928 penicillin discovered by Alexander Fleming..
 1950 to 1960 was the golden age natural product antibiotic.
 Since then, the discovery of antibiotic was declined.
 Since 1962 only two new classes of antibiotics discovered.

4. Post antibiotic era
 Overuse of antibiotics in clinical, veterinary and agriculture felids
have led to antibiotic resistance (Altamirano and Barr 2019).
 In 2019, WHO announced that ten threats face global health:
Antimicrobial resistance was one of them.
 A recent review suggests that ten million lives will be lost each
year by the year 2050.

5. 1. Bacteriophage Therapy
 Bacterial viruses, known as bacteriophage,
were discovered 20 years after discovering
viruses.
 After scientists knew there is a battle
between phages and bacteria, they tried to
use phages in many applications such as
biopreservation, biosanitation, phage
therapy.

6. The lytic cycle
The lysogenic cycle
How Phages Work ?
 Phage invades bacteria in order to
make their genome and proteins. Then,
it will rupture the host cell and release
new phages..
 Advantages: Bactericidal, Dosing by itself,
Species-specific and Keeps normal flora safe ..
 FDA approved phage cocktails for use in the
agri-food sector in order to prevent
Foodborne bacterial pathogens and improve
food safety..

7. 2. Anti-quorum Sensing
 Bacteria produce molecules and send
them outside of the cell such a signal
to other bacteria. this phenomenon
called quorum sensing which lead
Biofilm formation.
 In recent years, several anti-quorum
sensing compounds were reported in
plants and microbes.
A community
is always
stronger than
an individual

8. Quorum sensing inhibitors (QSIs) have either been obtained from
natural sources like plants and fungi or prepared as synthetic
compounds.
should not interfere
with the basal
metabolic processes
low molecular mass
should not be toxic

9. 3. Bacteriocin
Bacteriocins produced by bacteria and Are
Defined As Ribosomally Synthesized
Antibacterial Peptides/Proteins That Either Kill
Or Inhibit The Growth Of Closely Related
Bacteria.
More Than 200 Bacteriocins Were Described..
They Can Function As Natural Food
Preservatives Through The Inhibition Of
Spoilage Or Pathogenic Bacteria..

10. Bacteriocins Antibiotics
Restrict their activity to strains of species
related to the producing species and
particularly to strains of the same species.
Antibiotics on the other hand have a wider
activity spectrum and even if their activity is
restricted this does

11. 4. Probiotic
 Probiotics are defined as microorganisms that live in symbiosis with the
human host.
 Currently, the main probiotic microorganisms used by humans are
Lactobacillus spp.
The mechanisms of action:
1) Producing inhibitory substances and hydrogen peroxide inhibit both gram +
and - ..
2) Blockage of adhesion sites..
3) Competition for nutrients..

12. 5. Predatory bacteria ‘living antibiotic’
Small Gram-negative bacteria that naturally
invade and kill Gram-negative pathogens of
humans, animals and plants)
Mechanism of action:
Creates a porthole in a host’s cell membrane to enter
its body. Once inside, it seals the hole up and then
releases enzymes to digest the host’s contents.
 Human immune response to predatory bacteria ?!

13. Predatory bacteria

15. 6. Combining Antimicrobial Peptides with
Nanotechnology
 It make up by combinations of antimicrobial Peptides
(Amps) And Several Nanoparticles And Quantum Dots.
 Conjugation and functionalization of nanoparticles with
potentially active antimicrobial peptides have added
advantages that widen their applications in the field of drug
discovery

17. Mechanism of work:
• Target and neutralization of pathogenic bacteria and toxins, by ultrasound-propelled biomimetic nanorobots.
• The gold body of the nanorobots responds to ultrasound, which gives them the ability to swim around rapidly
without chemical fuel.
• This method are used in vitro.
7. Nanorobots
Gold nanowires cloaked
with a hybrid of red blood cell (RBC)
membranes and platelet (PL) membranes.

18. Sources
https://www.frontiersin.org/articles/10.3389/fmicb.2021.695081/full
Alternatives to Conventional Antibiotics in the Era of Antimicrobial Resistance: Trends in
Microbiology (cell.com)
These Robots Kill Antibiotic-Resistant Bacteria – ASME
Bacteriocin - an overview | ScienceDirect Topics
Probiotics as an alternative antimicrobial therapy: Current reality and future directions –
ScienceDirect
Inner Workings: Probing predatory bacteria as an antibacterial remedy | PNAS