BIOL 3332 Lecture Notes - Lecture 16: Quorum Sensing, Pilus, Gram-Negative Bacteria
Document Summary
Lecture 16: bacteria take up naked dna fragments from the environment. They can use these fragments and incorporate them into their chromosome. They can also use the dna as a food source: natural transformation= bacteria naturally perform transformation. If there are a lot of competence factors. You activate the transformasome complex: lets in single stranded dna. Dependent on cell density quorum sensing. Uses a type iv pilus: artificial transformation. Conjugation: requires cell to cell contact. By means of a sex pilus: fertility (f) factor promotes conjucation. Donor is f+ and recipient is f- The recipient does not have the f factor. Can be located on a plasmid or on the bacterial chromosome. Contains conjugation specific genes: tra genes= transfer genes, sex pilus genes, relaxosome, orit origin of transfer, oriv origin for replication in the vegetative, first off a conjugation bridge forms state. Then it is replicated whilst being transferred to the recipient cell.