There is the fifth video by Miss Aymen Arif Sindh Biotechnologist Association has taken initiative for all young scientists, researchers, and students to have the platform to show their talent and interest in different activities. Topic: Plasmids and its types Presentation by: Aymen Arif Research Officer at Halal Food and testing Laboratory, Industrial Analytical Center, H.E.J (ICCBS). Youtube: https://www.youtube.com/watch?v=-spdnc-2z6Q

1. PLASMIDS
PRESENTED BY:
AYMEN ARIF
SINDH BIOTECHNOLOGIST
ASSOCIATION (SBA)

2. Joshua Lederberg
• American Biologist who first
discovered plasmids in bacteria
and indicate that bacteria can
mate and exchange genes in
1952.
• He won Noble Prize for this
discovery along with Beadle and
Tatum.

3. UNDERSTANDING A PLASMID
 Small, circular double-stranded DNA
molecules
 They can exist independently of host
chromosomes
 They have their own replication origins
and are autonomously replicating and
stably inherited .
 Plasmids and bacterial chromosomes
are separate replicons.
 They range in size from few hundreds
to thousands genes (around 8-10 kbp)

4. STRUCTURE
 An Origin of replication (ORI)
region.
 Multiple cloning sites( a
polylinker to clone the gene
of interest) .
 An antibiotic resistance
gene (Selectable marker).
 Occurrence: Bacteria, fungi,
or yeast

5. pBR322
• An origin of replication (ori)
• Two genes that confer resistance to
different antibiotics (tet R , amp R )
• Several unique recognition sequences
(EcoRI, BamH1) Small size (4,361
bp).

6. TYPES OF PLASMIDS
1. Fertility Plasmids ( F-PLASMID ) – carry the fertility genes (tra-
genes) for conjugation, the transfer of genetic information between
two cells.
2. Resistance Plasmids (R-PLASMID) – Contain genes that can build
resistance to antibiotics or poisons.
3. Colicins Plasmids (COL-PLASMIDS) – contain genes that encode for
the antibacterial polypeptides called bacteriocins, a protein that
kills other strains of bacteria. The col proteins of E. coli are encoded
by proteins such as Col E1.

7. • Degradative Plasmids – Allows to digest unusual substances.
• Virulence Plasmids – Turn bacterium into a pathogen
• Episomes an episome is a plasmid of bacteria or viral DNA that can
integrate itself into the chromosomal DNA of the host organism .

8. BY THEIR ABILITY TO TRANSFER TO
OTHER BACTERIA
PLASMIDS
CONJUGATIVE
PLLASMIDS
NON-
CONJUGATIVE
PLLASMIDS
INTERMEDIATE
PLASMIDS

9. MODE
OF
ACTION

10. APPLICATIONS OF PLASMIDS
 Prevention of disease.
 Production of therapeutic
drugs and proteins
 Gene knockout study
 Gene Cloning and Gene Mapping

11. BIBLIOGRAPHY
• National Center for Biotechnology Information.
https://www.ncbi.nlm.nih.gov/
• Info:Main Page. https://www.newworldencyclopedia.org
• Margo R Monroe. Plasmids 101: What is a plasmid? by the addgene
blog, 2014.
• Carsten Voss. Production of plasmid DNA for pharmaceutical use.
Biotechnol Annu Rev. 2007; 13: 201–222