how is the N-terminus of the polypeptide modified to become a mature protein? - Answer-removal of the N-formyl group from N-fMet
______ are proteins that correct misfolding and suppress incorrect folding as the protein comes out of the E site of rRNA - Answer-chaperones
_____ is a chaperone t...
MCB 3020 - Exam 2 (Chapters 11, 13, 16,
17, 19) Questions and Answers
how is the N-terminus of the polypeptide modified to become a mature protein? -
Answer-removal of the N-formyl group from N-fMet
______ are proteins that correct misfolding and suppress incorrect folding as the protein
comes out of the E site of rRNA - Answer-chaperones
_____ is a chaperone that associates w the ribosome and masks hydrophobic regions
so they don't fold with each other prematurely - Answer-trigger factor
______ is a chaperone that helps iron-sulfur centers obtain their iron atom - Answer-
DnaJ/DnaK/GrpE
_____ is a chaperone that forms a cage for misfolded proteins to be uncoiled and
refolded, away from cytoplasmic crowding - Answer-GroES/GroEL
______ and _____ are chaperones that are cytoplasmic and require ATP - Answer-
DnaJ/DnaK/GrpE and GroES/GroEL
_____ is when proteins are moved from the cytoplasm to/across the plasma membrane
- Answer-translocation
protein ____ refers to the movement of proteins from the cytoplasm to the external
environment - Answer-secretion
the ____ system is the name for the general secretion pathway - Answer-Sec
the ____ -terminal is the signal peptide/sequence - Answer-N
____ (SRP) is a protein-RNA complex that surveys actively translating ribosomes and
will escort the entire ribosome to the membrane. It looks for membrane proteins with
really hydrophobic signal peptides - Answer-signal recognition particle
the alternative route to the membrane is via the _____ protein - Answer-SecA
the _____ system is another translocation route that will only secrete folded proteins -
Answer-Tat
the 3 main translocation systems for gram-positive and gram-negative bacteria are: -
Answer-Sec
SRP
Tat
,after polypeptide translocation, the two final maturation steps are - Answer-1) signal
peptidase removing the signal peptide
2) protein disulfide isomerase (PDI) forming disulfides
_____ is the enzyme that removes the signal peptidee - Answer-signal peptidase
_____ (PDI) is the enzyme that oxidizes cysteine residues to form disulfides - Answer-
protein disulfide isomerase
____ is a second signal that some proteins have at the C-terminus that directs them to
sortase enzymes embedded in the membrane - Answer-sorting signal
_____ is an enzyme that catalyzes the rxn btw the sorting signal and Lipid II, the
peptidoglycan precursor - Answer-sortase
_____ is the peptidoglycan precursor - Answer-Lipid II
protein secretion in gram-______ bacteria requires crossing 2 membranes - Answer-
negative
secreted proteins that cause host injury are called _____ - Answer-effectors
the 3 two-step secretion systems involved in protein secretion in gram-negative cells
are: - Answer-1) type 5
2) type 2
3) type 9
type 2 secretion systems are only found in _____ - Answer-proteobacteria
type 9 secretion systems are only found in ____ - Answer-bacteroidetes
the 5 one-step secretion systems involved in protein secretion in gram-negative cells
are: - Answer-1) type 1
2) type 3
3) type 4
4) type 6
5) type 7
proteins exported by the type ___ secretion system (a one-step system) pass through
an ATP binding cassette, a membrane fusion protein, and a barrel protein - Answer-1
the type ___ secretion system is a one-step system that works as a molecular syringe -
Answer-3
, the type ___ secretion system is a one-step system that is used for DNA transfer, that
works at the cell poles, using integral membrane proteins, ATPases, and a pilus -
Answer-4
the type ____ secretion system is a one-step system that is a contractile weapon used
by bacteria to deliver toxins to neighboring cells, whether bacterial or eukaryotic -
Answer-6
the type ____ secretion system is a one-step system that is found in Mycobacterium
spp. despite that being a gram-positive bacterium. this ss gives important virulence
factors to host cells. it has roles in DNA transfer, cell envelope integrity, sporulation,
metal uptake, and competition for nutrients - Answer-7
________ (OMVs) are made of a lipid bilayer of outer membrane + lipopolysaccharide
and integral outer membrane proteins. the lumen contains molecules found in the
periplasm. these are ONLY FOUND in gram-NEGATIVE bacteria - Answer-outer
membrane vesicles
_____ (EVs) are vesicles that pinch off the plasma membrane and have to cross a thick
peptidoglycan cell wall. these are ONLY FOUND in gram-POSITIVE bacteria - Answer-
extracellular membrane vesicles
_____ initiates the formation of the replication bubble - Answer-DnaA
____ is a protein involved in termination of transcription - Answer-rho
_____ is the subunit/factor on the replisome that recognizes the promoter region -
Answer-sigma factor
the Shine-Dalgarno sequence is found on the _____ - Answer-mRNA
_____ binds to the initiation complex first (translation) - Answer-IF-3
the protein that promotes translation termination is called _____ - Answer-release factor
genes that encode housekeeping functions and are needed almost always are called
_____ - Answer-housekeeping genes
genes that are expressed continuously are called _____ - Answer-constitutive genes
an ______ enzyme is one whose level rises in the presence of a small effector molecule
called an inducer - Answer-inducible
many catabolic enzymes are _____ enzymes - Answer-inducible
many anabolic enzymes are ____ enzymes - Answer-repressible
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller lectknancy. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £13.50. You're not tied to anything after your purchase.