Lecture 3.1: Bacterial Genetics 1 Flashcards
describe typical genetic organization
a single promoter drives expression of a single gene
what is a promotor?
site on DNA where RNA polymerase binds
do bacterial genes have introns?
no
where do transcription and translation occur in bacteria?
in the same compartment
an opening reading frame starts with __ and ends in __
ATG; TAA, TAG, TGA
an open reading frame has potential to encode a__
protein product
what happens when bacterial genes are co-expressed?
single promotor controls expression of multiple genes
each reading frame has its own corresponding __
Ribosome binding site
what happens in the ribosome binding site?
proteins are made
genes are regulated based on
environment/immediate factors such as temp, nutrients, growth cycle, infections
bacteria have ___ that control a dedicated set of genes
transcriptional activators
what are transcriptional activators?
proteins that bind to DNA at specific sites to promote RNA polymerase (turn on transcription)
what are sigma factors?
proteins that bind to RNA polymerase and DNA sequence to promote transcription
bacterial genes do not have introns therefore, ___ does not need to occur
splicing to remove introns
what are introns?
sequences of DNA that dont encode for protein sequence
in bacteria, both transcription and translation occur in the
cytoplasm
mRNA starts to form at the ___ and ends at the ___
transcriptional start site; terminator
do eukarya experience co-expression of genes?
no
five open reading frames leads to the transcription of ___ genes
5
transcriptional regulation prevents
all genes being expressed all the time
what species of bacteria is know to have 14 sigma factors? Why?
bacillus; because they want spores created at the right time and not to be expressed too early/too late
