Bacterial recombination can occur through generalized transduction, where bacterial viruses called bacteriophages inadvertently package bacterial DNA from one host and deliver it to another during infection. Bacterial chromosomes are usually circular DNA molecules located in the nucleoid region. Plasmids are smaller ring DNA molecules that also reside in bacteria and can help them survive stress. Gene mapping techniques like physical mapping using molecular markers and genetic mapping using restriction sites help determine the locus and distance between genes on bacterial chromosomes. These mapping techniques benefit medicine, agriculture, forensics, and environmental applications.

2. Recombination in bacteria

3. Bacterial recombination

7. Generalized transduction:

12. significance:

13. Bacterial chromosomes

14. Bacterial chromosomes:
• Bacterial chromosomes consists of DNA molecule and is
located at a region is called nucleloid.
• The chromosomes along with proteins formed the irregular
nucleoid.
• In E.coli the length of cell is many times as compared to the
length of cell.

15. Plasmids:
• In addition to normal bacterial DNA cells have smaller ring of
DNA is called plasmid.
• Types of plasmids
• Conjugative plasmid
• non-conjugative plasmid

16. How plasmid help bacteria:
• Plasmids help the bacteria to survive in stress.
• Bio-technology delivery DNA

17. Bacterial chromosomes:
• Multiple circular chromosomes
• Linear chromosomes

18. Functions of bacterial chromosomes:
• Transcription
• translation

19. Gene mapping
introduction

20. Gene mapping:
• Technique use to find locus of the gene and distance between the two
genes.
• Gene map is the Graphical representation of gene and DNA markers
on the genome of organisms.

21. Types of gene mapping:
• Physical mapping
• Genetic mapping

22. Markers of physical and genetic
mapping:
• Physical mapping:
• Genes with physical phenotype
• Molecular marker such as RFLP
• Genetic mapping:
• Restriction enzyme sites
• cDNA clones
• Expressed sequence tags
• Any unique DNA sequence

23. Benefits of genetic mapping:
• Medicine
• Agricultural applications
• Forensic applications
• Energy and environment

24. Gene mapping by
conjugation

25. MappingbyInterruptedMatingExperiment
 The two French geneticists, F.Jacob and E. Wollman in the late 1950’s.
 The genotypes of the two E. coli strains involved was:
 Donor – Hfr: leu+ azi’r tonA’r lac+ gal+ str’s
 Recipient – F-: leu- azi’s tonA’s lac- gal- str’r
 The two strains mixed in nutrient medium at 37°C to allow conjugation to start.
 The conjugation can be interrupted using kitchen blender.
 By interrupted the matting at various times.
 This technique can be used to make a map of circular E.coli chromosome.

26. Experiment

27. Time of gene Transfer

28. Result

29. Map:

30. Gene mapping by
transformation and
transduction:

31. Transformation:
• What is transformation:
• Discovery:
• Competence cell:
• Process of transformation

32. Types of transformation:
• There are two types of transformation:
• Natural transformation
• Artificial transformation

33. Natural transformation:
• It is the ability of recipient cell absorb donor DNA and
become transformed, it is said to be a competent cell.it
also having the property of take up DNA .

34. Artificial transformation
techniques:
Electroporation:
• Method of promoting
competence.
• When electric field of 20vis
applied artificial pore of water
is produced. which is
hydrophobic outside and
hydrophilic inside .
• DNA can pass through this
hydrophilic pore. Polar
molecules cannot pass through
this hydrophilic pore. This
method is commonly used
because of its abundant
availability.
Calcium chloride:
• The cells are dipped in a
solution containing divalent
cations of calcium chloride
under cold condition.
• Ca2+ interacts with the
negatively charged creating an
electrostatically neutral
situation.
• lowering the temperature that
stabilizes the functions of
charges. when the temperature
is increased that caused the
imbalance in temperature from
this DNA get into the cell.

35. Linkage and gene mapping:
• Co-transformation:
• It is an indication that two genes linked to each other.

36. Transduction:
• Transduction, a process of genetic recombination in
bacteria in which genes from a host cell (a bacterium) are
incorporated into the genome of a bacterial virus
(bacteriophage) and then carried to another host cell when
the bacteriophage initiates another cycle of infection.