BIOL3150 - MIDTERM#2 EXAM QUESTIONS AND ANSWERS
WITH COMPLETE SOLUTIONS VERIFIED
what is a protein domain
any segment of a polypeptide chain that can fold independently into a compact, stable
structure
why are most dna binding proteins specific to certain chemical groups within
DNA
to catalyze a specific reaction on the DNA such as transcription or termination by
blocking transcription
biological information flows from
DNA to RNA to Protein
gene expression
process of gene transcription into mRNA followed by translation of mRNA into protein
constitutive genes
proteins and rna molecules that are needed in the cell under all growth conditions
two major levels of regulation in the cell
- one that controls amount of an enzyme
- one that controls activity of preexisting enzymes
two major levels of regulation in the cell - one that controls amount of an enzyme
regulates level of transcription and translation, slower process (mins)
two major levels of regulation in the cell - one that controls activity of preexisting
enzymes
, post translational regulation and very rapid process (seconds)
DNA binding proteins and transcriptional regulation
negative control; repression and induction
positive control; activation
global control
DNA binding proteins - what can influence the binding of the regulatory proteins
to DNA?
small molecules (metabolites)
how do DNA binding proteins interact w dna?
sequence specific manner
- specificity is provided by interactions between amino acid side chains and chemical
groups on the bases and sugar phosphate backbone of dna
- major groove of dna is main site of protein binding
- inverted repeats frequently are the binding sites for regulatory proteins
DNA binding proteins - homodimeric proteins
proteins composed of two identical polypeptides
- protein dimers interact w inverted repeats on DNA where each polypeptide binds to
one inverted repeat
DNA binding proteins - helix turn helix, which organisms use it?
- first helix is the recognition helix and the second is the stabilizing helix
- dna binding proteins from bacteria contain helix turn helix (lac and trp repressors of
E.coli)
zinc finger - dna binding protein, which organisms use it?
WITH COMPLETE SOLUTIONS VERIFIED
what is a protein domain
any segment of a polypeptide chain that can fold independently into a compact, stable
structure
why are most dna binding proteins specific to certain chemical groups within
DNA
to catalyze a specific reaction on the DNA such as transcription or termination by
blocking transcription
biological information flows from
DNA to RNA to Protein
gene expression
process of gene transcription into mRNA followed by translation of mRNA into protein
constitutive genes
proteins and rna molecules that are needed in the cell under all growth conditions
two major levels of regulation in the cell
- one that controls amount of an enzyme
- one that controls activity of preexisting enzymes
two major levels of regulation in the cell - one that controls amount of an enzyme
regulates level of transcription and translation, slower process (mins)
two major levels of regulation in the cell - one that controls activity of preexisting
enzymes
, post translational regulation and very rapid process (seconds)
DNA binding proteins and transcriptional regulation
negative control; repression and induction
positive control; activation
global control
DNA binding proteins - what can influence the binding of the regulatory proteins
to DNA?
small molecules (metabolites)
how do DNA binding proteins interact w dna?
sequence specific manner
- specificity is provided by interactions between amino acid side chains and chemical
groups on the bases and sugar phosphate backbone of dna
- major groove of dna is main site of protein binding
- inverted repeats frequently are the binding sites for regulatory proteins
DNA binding proteins - homodimeric proteins
proteins composed of two identical polypeptides
- protein dimers interact w inverted repeats on DNA where each polypeptide binds to
one inverted repeat
DNA binding proteins - helix turn helix, which organisms use it?
- first helix is the recognition helix and the second is the stabilizing helix
- dna binding proteins from bacteria contain helix turn helix (lac and trp repressors of
E.coli)
zinc finger - dna binding protein, which organisms use it?
