1. MICROBIOLOGY
CONJUGATION
Meghna V
III Semester
MGMCH

2. BACTERIAL CONJUGATION WAS FIRST
DISCOVERED BY
Lederberg And Tatum
IN 1946
IN Esch.coliK12 STRAINS

3. CONJUGATION
BACTERIA A
BACTERIA B
TRANSFER OF GENETIC MATERIAL FROM BACTERIA A
TO BACTERIA B BY MATING OR CONTACT IS CALLED
CONJUGATION.

4. WHO IS A DONOR?
F PLASMID
DONOR
F+
MALE CELL
ABSENT
RECIPIENT
F–
FEMALE

5. F PLASMID
FERTILITY FACTOR
SEX FACTOR
TRANSFER FACTOR

6. THIS F PLASMID ENCODES FOR THE SEX PILUS

7. WHAT HAPPENS DURING
CONJUGATION?

8. THE ONCE FEMALE RECIPIENT CELL NOW
BECOMES THE MALE DONOR CELL
THIS CHARACTERISTIC OF MALENESS (F+) IN
BACTERIA IS TRANSMISSIBLE OR
INFECTIOUS

9. What is Hfr cell?
When F factor/ plasmid exists in
an integrated state with the host
chromosome

10. Hfr CONJUGATION

11. F+ (free plasmid)
Hfr ( integrated )
REVERSIBLE
TURNS A (F-)
INTO A (F+) UPON
CONJUGATION
CONJUGATION WITH A
Hfr , AN (F-) RARELY
BECOMES (F+) BUT IT
RECEIVES CHROMOSOMAL
DNA FROM THE
DONOR

12. REVERSIBLE
(F+)
Hfr

13. SEXDUCTION

14. F+
Hfr
REVERSIBLE
WHEN THE F FACTOR REVERTS FROM
INTEGRATED
FREE STATE IT MAY
SOMETIMES CARRY WITH IT SOME
CHROMOSOMAL DNA FROM ADJACENT SITE OF
ITS ATTACHMENT
SUCH AN F FACTOR IS KNOWN AS F’ FACTOR

15. ( F’) + ( F-)
SEXDUCTION
WHEN (F’) CONJUGATES WITH A RECIPIENT (F), IT TRANSFERS, ALONG WITH THE F
FACTOR, THE HOST DNA INCORPORATED
WITH IT.

16. MEDICALLY IMPORTANT FACTORS
WHICH CAN BE TRANSFERRED BY
CONJUGATION
1. COLICOGENIC FACTOR (COL)
2. RESISTANCE TRANSFER FACTOR (RTF)

17. THANKYOU