BIOL 2051 Chapter : Chapter 9
Document Summary
Chapter 9 gene transfer, mutations, and genome evolution: dna sequence is not static, horizontal gene transfer, transformation. Insertions new gene or just nonsense: effects of gene transfer, spreads useful genes among bacteria don"t have to be in same species or that close in order to pass, antibiotic resistance genes. Spread wherever antibiotics are overused: hospitals, farms, pathogenicity islands get genome from other organism, encode genes for cell to act as a pathogen, difference between typical e. coli in gut and pathogenic e. coli 0157:h7. Makes new toxins that are disease causing: genes to degrade special metabolites (oil spills) less competition for food, mechanisms of horizontal gene transfer sources, transformation, transduction, conjugation. Transformation- competent cell picks up free dna from the environment; from old cells that have lysed, etc: some cells are naturally competent (bacillus, some cells can be made competent: ____electroporation____- electrical shock opens pores in cell membrane, dna enters through pores.
