Chapter Microbial genetics 8.1 DNA as genetic material 8.2 Mutation 8.3 DNA repair
Chapte8 Microbial genetics 8.1 DNA as genetic material 8.2 Mutation 8.3 DNA repair
Microbial molecular biology and genetics a clone: a population of cells that are derived asexually from a parental cell and are genetically identical Genome: all the genes present in a cell or virus Central dogma: DNA→>RNA→> protein transcription translation
Microbial molecular biology and genetics • A clone: a population of cells that are derived asexually from a parental cell and are genetically identical. • Genome: all the genes present in a cell or virus. • Central dogma: DNA→RNA → protein transcription translation
8.1 dNA as genetic material Coll t No capsule mooth (S) Lie S strain Live R Live R strain Heat→kled Heat-killed s strain Livo S and R strains isolated from dead Figure 1l.1 Grifmith's Transformation Experiments. (a) Mice died of pneumonia when injected with pathogenic strains of s pneumococci, which have a capsule and form smooth-looking colonies. (b) Mice survived when injected with a nonpathogenic strain of R pneumocoeci,whic lacks a capsule and forms rough colonies. (e) Injection with heat-killed strains of S pneumococci had no effect. (d) Injection with a live R strain and a heat-killed S strain gave the mice pneumonia. and live S strain pneumococci could be isolated from the dead mice
8.1 DNA as genetic material
R cells+ purified s cell polysaccharide R colonies R cells purified S cell protein R colonies R cells purified s cell RNA R colonies R cells purified S cell DNA S colonies S cell extract protease +R cells S colonies S cell extract + RNase +R cells S colonies Figure 11. 2 Experiments on the Transforming Principle. Summary of the experiments of Avery, MacLeod, and McCarty on the transforming principle. DNA alone changed R to S cells, and this effect was lost when the extract was treated with deoxyribonuclease. Thus DNA carried the genetic information required for the R to S conversion or transformation
The hershey-Chase experiments s protein DNA Blender treatment coat Protein DNA Blendor treatment
The Hershey-Chase experiments