F-Plasmid-Fertility plasmids 1s3 100KB Tn1000 Can be cured with 1000 acridine orange tra region s· compatibility(imc) Origin of replication (oriS) Transposable elements 75 25 tra region phi: phage inhibition Is (insertion sequence) rep: replication functions inc, rep, oris, phi
F-Plasmid-Fertility Plasmids • 100 KB • Can be cured with acridine orange • Incompatibility (inc) • Origin of replication (oriS) • Transposable elements (Tn) • tra region • phi: phage inhibition • IS (insertion sequence) • rep: replication functions
Cell to Cell transfer of plasmids Conjugative: Plasmids that govern their own transfer by cell-to-cell contact are called conjugative(not all plasmids are conjugative) Some conjugative plasmids can transfer genetic information between distintly related organisms (between gram-positive and gram-negative bacteria, between bacteria and plant cells, and between bacteria and fungi), it is important for evolution. Chromosome Plasmid Conjugation(接合作用)
Cell to Cell Transfer of Plasmids • Conjugative: Plasmids that govern their own transfer by cell-to-cell contact are called conjugative (not all plasmids are conjugative) • Some conjugative plasmids can transfer genetic information between distintly related organisms (between gram-positive and gram-negative bacteria, between bacteria and plant cells, and between bacteria and fungi), it is important for evolution. Conjugation (接合作用）
Plasmid biology Chromosome (a)Plasmid replication inde of chromosom (c)Cell-to-cell transfer during conjugation p Somes (a) Integration of plasmid into chromosome
Plasmid Biology Episomes
Plasmid Biology Growth cuning (b) Curing of plasmid
Plasmid Biology
Types of Plasmids and Their Biological significance The presence of plasmids in a cell can have a profound influence on the cells phenotype the ability of conjugation the ability of rhizobium to interact with plants the resistance to antibiotics and heavy metals the degradation of octane, camphor et al the production of enterotoxin the applications in genetic engineering
Types of Plasmids and Their Biological Significance • The presence of plasmids in a cell can have a profound influence on the cell’s phenotype: – the ability of conjugation – the ability of Rhizobium to interact with plants – the resistance to antibiotics and heavy metals – the degradation of octane, camphor et al – the production of enterotoxin – the applications in genetic engineering