BIOL 1107 Study Guide - Midterm Guide: Lac Operon, Galactoside, Allolactose
Document Summary
Bacteria: regulation due to presence of specific nutrients. Transcription - do or don"t do transcription. Translation - stop protein synthesis at mrna state. Lac operon (operon- set of coordinated genes that is transcribed together for a single purpose; cotranscription) | codes for repressor xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx laci promoter laci promoter operator codes for repressor, expressed constitutively (all the time) lacy lac operon laca lacz laci codes for repressor repressor- doing negative control on lac operon inducer- allolactose. Allolactose binds to repressor in allosteric regulation and forces the repressor to let go of the operator to allow transcription to begin. Allolactose does post-translational control on repressor by shutting it off/inhibiting its function through allosteric regulation. Galactoside permease (lacy): protein channel that transports lactose into cell. Beta-galactosidase (lacz): breaks down lactose into glucose and galactose, can convert lactose into allolactose to be inducer. Transacetylase (laca): exports extra sugars from cell (galactose), glucose will be used or stored.