Bacterial genetics Flashcards
DNA nucleotides
2 Purines (AG)
2 Pyrimidine (CT)
DNA nucleotides held by which bond
Hydrogen
RNA Nucleotides
2 Purines (AG)
2 Pyrimidine (CU)
Types of Mutation
Point Mutation
Frameshift Mutation
Classification of Point Mutation
Transition - Purine replaced by purine or Pyrimidine replaced by Pyrimidine
Transversion - Purine replaced by Pyrimidine or vice versa
Types of Point Mutation
Silence Mutation
Missense Mutation eg SCA
Non-sense Mutation Eg Beta Thalassemia
Frameshift Mutation means
Shift in frame
Deletion of nucleotides or addition of nucleotide
Methods of Gene transfer in Bacteria
Transduction
Conjugation
Transformation
Who first identified Transformation method
Griffith
Transformation method is finally rediscovered by
Avery, McLeod and McCarty
How bacteria transfers gene by Transformation method
Transfer of free DNA
uptake of soluble DNA fragments by bacteria
Mediator in Transduction process
Bacteriophage
Transduction process is first demonstrated in which organism
Salmonella
Transduction is most common method of drug resistance in which organism
S. Aureus
Bacteriophage cycle
Lytic cycle - break and come out
Lysogenic cycle - combined with bacteria
Types of Bacteriophage
Virulent phage - Follow only lytic cycles
Eg T1,T2 phage of Ecoli
Temperate Phage - Follow both lytic and Lysogenic cycle
Eg Lambda phage of Cycle
Types of Transduction
Specialised Transduction
Generalized Transduction
Cycle followed in Generalized Transduction
Lytic cycle
Cycle followed in Specialized Transduction
Lysogenic cycle
Generalized Transduction occurs due to
Mispackaging
Specialised Transduction occurs due to
Defective excision during induction of a prophage
Generalized Transduction is mediated by which bacteriophage
Virulent or temperate phage
Specialised Transduction is mediated by which phage
Temperate Phage only
Conjugation method is first demonstrated by
Leduberg and Tatum in Ecoli
Most common mode of MDR is done by which method
Conjugation
M/C. Bacterial resistance in which method
Conjugation Except
S Aureus - Transduction
S. Pneumoniae - Transformation
Plasmid means
Extrachromosomal circular dsDNA
When plasmid combines with Host cell DNA, termed as
Episone
Types of Plasmid
Virulence Plasmid
Fertility Plasmid
Resistance Plasmids
Col Plasmids - code for Bacteriocin
Types of Plasmid based on Transfer
Conjugate Plasmid
Non Conjugate Plasmid
Conjugate Plasmid is
Transferred vertically as well as Horizontally
Non Conjugative Plasmid
Only transferred Vertically (Bacteria to offspring)
F Plasmid
Fertility factor
F+ Male
F- Female
Hfr means
DNA and Plasmid combined with each other
F’ MEANS
Plasmid separated along with DNA
F+ X F-
F+F+
F+ X F-
F+F+
Hfr X F-
F-
F’ x F-
F’F’
Types of Drug Resistance
Transferrable Drug Resistance
Mutational Drug resistance
Which type of drug resistance is more dangerous
Transferrable Drug resistance - Difficult to treat
Mutational Drug resistance
Due to single mutation
Easier to treat
Restriction endonuclease are produced by bacteria for
Defense against foreign bacteria
Cofactor of Restriction endonuclease
Mg+2
Bacteria protects it own genome from Restriction endonuclease by
Methylation
CRISPR-CAS9 is
Bacterial defense against virus infection
CRISPR-CAS9 Full form
Clustered Regularly Interspaces short Palindromic repeats
