Proteins and Quality Control Flashcards
What Are Molecular Chaperones?
proteins that assist the covalent folding or unfolding and the assembly or disassembly of other macromolecular structures
What are Chaperonins?
Proteins that facilitate folding of mis folded proteins
Acetylation
process where an acetyl functional group is transferred from one molecule (in this case, Acetyl-Coenzyme A) to another
Phosphorylation
post-translational modification of proteins in which an amino acid residue is phosphorylated by a protein kinase by the addition of a covalently bound phosphate group
Glycosylation
reaction in which a carbohydrate, i.e. a glycosyl donor, is attached to a hydroxyl or other functional group of another molecule
Hydroxylation
chemical process that introduces a hydroxyl group (-OH) into an organic compound
Methylation
a process by which methyl groups are added to the DNA molecule. Methylation can change the activity of a DNA segment without changing the sequence
Carboxylation
a chemical reaction in which a carboxylic acid group is introduced in a substrate
What are some forms of protein Modifications?
Acetylation, Phosphorylation, Glycosylation, Hydroxylation, Methylation, Carboxylation
What are 3 ways Proteins are Degradated?
- Within lysosomes
- Degestive proteases
- Ubiquitin-mediated protein degradation
What is Ubiquitin?
is a small regulatory protein that has been found in almost all tissues. The addition of ubiquitin to a substrate protein is called ubiquitination or ubiquitylation
How can Ubiquitin effect proteins?
Ubiquitination can affect proteins in many ways: it can signal for their degradation via the proteasome, alter their cellular location, affect their activity, and promote or prevent protein interactions
Sepcificity
ability of one protein to bind one molecule in preference to another
Affinity
strength of binding
What is an example of an Enzyme working as a catalyst?
Kinases
