MIIM20001 Lecture Notes - Lecture 20: Dna Gyrase, Bacillus Cereus, Antimicrobial Resistance

• School: University of Melbourne
• Department: Microbiology and Immunology
• Course: MIIM20001
• Professor: A/Prof Jason Mackenzie

Document Summary

Extra cookbooks: not possible for a bacterial genome to contain every gene that might be useful, evidence of gene transfer- antibiotic resistance. Metabolic burden if bacterial genome contained ever gene. Plasmids: extrachromosomal, self-replicating dna molecules, diverse tools for bacteria and for us, add flexibility to a bacterium. In the lab plasmids can be manipulated to encode genes for a variety of functions incredible importance to biotech: replicate independently of circular chromosome. What purpose do they serve: contain genes that are not essential for bacterial growth, offer the bacteria a selective advantage under specific conditions (virulence, resistance, metabolism) Presence of absence of a plasmid can transform the phenotype. Very genetically related different plasmids hence different. Having a plasmid and the type of plasmid can change the phenotypically phenotype of the particular strain. Plasmid structure: usually present as double stranded circular dna molecules, although some are linear bacterium.