Bio lecture 28-30 slide 14
What enzyme has the ability to detect and remove mismatched bases?
DNA pol III
What activity is used to remove mismatched nucleotides?
3'-5' exonuclease activity
What enzyme removes nucleotides FROM THE END of the polymer?
Exonuclease
When does proofreading occur?
DURING DNA replication
When does mismatch repair occur?
Shortly AFTER synthesis of the new DNA strand
Which enzyme cuts off the mispaired nucleotides WITHIN the DNA strand?
Endonuclease
What is the function of nucleotide excision repair?
Remove dimers formed by UV radiation and some other defects involving modified nucleotides that cause a SIGNIFICANT DISTORTION in the DNA helix
Which enzyme replaces the missing nucleotides in the nucleotide excision repair process?
DNA pol I
What are the secondary structure of proteins and what forms them?
Coiling or folding of the aa chain into alpha helix or beta pleated sheet. Results from H-bonds between atoms in the polypeptide backbone where R groups are NOT involved
Can all proteins have a secondary structure?
No