lecture 20 - Bacterial Protein Secretion

know Sec pathway, Know SRP pathway, know TAT pathway

This is the process of transferring proteins through one or both membranes

secretion

These are the three protein secretion pathways in Gram - and Gram +

Sec, SRP, TAT

What are the domain structures of signal peptides?

N-region, H-region, C-region

This region of signal peptides is used for export and transport

n-region

This region of signal peptides is hydrophobic

h-region

This region of signal peptidesis for cleavage

c-region

This component of Sec pathway is used for translocation of pre-protein to the SecYEG channel

SecA

This component of the Sec pathway chaperones new proteins to the cell membrane

SecB

This component of the Sec pathway form the transport channel

SecYEG

This component of the Sec pathway is used for refolding of the proteins

SecD/F

This component of the Sec pathway is responsible for membrane insertion

YidC

This component of the Sec pathway cleaves after AXA

SPaseI

This protein pathway is mediated through cotranslation export

SRP pathway

Delivers the stalled ribosome and its protein to the cell membrane to bind to FtsY

SRP

This delivers the signal sequence to the SecYEG translocon

FtsY

This protein in the TAT pathway recognizes signal sequence and recruits TatA

TatBC

This TAT pathway protein forms the channel for translocation and has an energy requirement (proton motive force)

TatA

This protein secretion system in Gram + bacteria works by covalently anchoring proteins to the peptidoglycan

Sortase pathway

This protein covalently anchors the proteins to the peptidoglycan

srtA