GENE20001 Lecture Notes - Lecture 12: Antimicrobial Resistance, Mobile Genetic Elements, Transposable Element
Document Summary
Mobile genetic elements that can move from one location in the genome to another. Dna segments that move by transposition (change in position). Encode only genes required for mobilisation and insertion into a new location. Its only function is to code for a transposase enzyme (allows it to move around the genome) They are similar in sequence but backwards relative to one another. Recognised by transposase to move a new copy elsewhere in the genome. Genes for mobilisation (transposase) and other unrelated functions (e. g. antibiotic resistance) A copy of the tn inserts into a new chromosome location and the original tn remains. Transposase cuts dna: twice at irs and twice at target sites. Single stranded dna filled in by dna polymerase. Plasmids encode resistance to antibiotics, heavy metal, antiseptics. More than one resistance gene, often located in transposons. Resistance to a number of drugs is acquired as a single genetic package located on an r plasmid.
