ch13 expression

• transcription inititiation
• transcription elongation
• translation
• posttranslation

housekeeping genes that are expressed continuously

genes that code for inducible enzymes such as beta galactosidase

an inducible enzyme that functions in a catabolic pathway

the activity of regulatory proteins

inhibit transcription (negative control) or promote transcription (positive control)

effector proteins

transcription

prescence of repressor at regulatory site which decreases mRNA synthesis

sequence of bases coding for one or more polypeptides nad promoter and operator or activator binding sites

regulated by lac represor which binds to the operator

regulated by catabolite activator protein (CAP) which binds to CAP site

presence of an activator protein at a regulatory region that promotes transcription

coordinates regulation of catabolite operons

• acive form is bound to cAMP
• inactive form is free of cAMP

adenyl cyclase

when little or no glucose is present

True

biphasic growth patter from preferred use of one carbon source over another when both are available

true

negative transcriptional control of repressible genes

in the absence of tryptophan

attenuation

folding of mRNA leader sequence determines if transcription continues or is terminated

false

non coding rnas that don't function as a normal rna