Virulence factor for Griffith's Experiment?
Casular polysaccaride is the structure that helps a pathogen cause infection or disease
What are the two pathways of Phage infection?
- Lytic (virulent).
- Lysogenic (temperate)
What is Generalized Transduction?
- Lytic Phage - Bacterial DNA is randoml incorporated into phage.
- Phages that are released have partial viral and bacterial DNA.
- Phage containing bacterial DNA transfers it to a new host cell.
What is Specialized Transduction?
- Specific Genes are transferred.
- Some Lysogenic phages insert at specific locationsin the chromosome.
- Lambda phage in E.Coli inserts between galactose gene & biotin gene
What is a Bacteriophage?
A virus that can infect bacteria
What is the structure of a bacteriophage?
- nucleic acid core covered in a protein coat.
- Have a head with genome, collar, tail sheath, plate, pin, tail fibers
Phage DNA that has incorporated into the host bacterium's DNA
What are Plasmids?
extrachromosomal, circular 2 stranded DNA molecules.
What are characteristics of Plasmids?
- self replicating.
- numerous copies per cell.
- genes coded for are useful, but not essential fo growth
What are F+ plasmids
- Contain Fertility (f) plasmids and make an F pilis.
- donor cells (male)
What are F- Plasmids?
- Fertility plasmids that code for f-pili.
- Direct their own transfer.
- recipient cells (female)
Types of Plasmids include:
- F plasmids.
- R (resistance) plasmids.
- Virulence Plasmids.
- Ti (Tumor inducing plasmids.
- bacteriocins (direct synthesis of bac. proteins)
R plasmids contain which gene?
Resistance (R) plasmids contain genes that provide resistance to various antibiotics
What is transposon?
- Tansposon is a jumping gene.
- a mobile sequence that contains genes with the abilit to move from one locaiton to another.
- may carry r gene.
- may interupt gene function.