Class Notes (839,552)
Canada (511,390)
MICB 202 (43)
All (12)
Lecture

Last Lecture on Microbes

4 Pages
94 Views

Department
Microbiology
Course Code
MICB 202
Professor
All

This preview shows page 1. Sign up to view the full 4 pages of the document.
Description
Salmonella intracellular survival strategies • Enters cell by reorganizing actin after injecting virulence factor o Can lyse vacuole and survive in cytoplasm o Can prevent fusion of phagosome and lysosome, survives in the phagosome o If it does fuse with a lysosome, bacteria is acidified and oxidized and hydrolyzed and subject to antimicrobial peptides • Salmonella ingested, taken up by cells similar to phagocytosis o Ligand to surface receptor binding o Injects Src into cell, causing actin rearrangement and phagocytosis o Salmonella can penetrate mucuosal surface through M cells, then move into a variety of different lymphatic cells of peyer’s patches o Induces a severe inflammatory response (neutrophils enter and prostaglandins released, cAMP activation)  Efflux of electrolytes and water, causing diarrhea, vomiting, headaches, chills  But can also sometimes be asymptomatic o Salmonella protein SopB reprograms epithelial cells to become M cells (preferred targets) • Type III secretion systems: o Needle like structures spanning bacterial membranes that deliver virulence proteins into host cells o Many gram negatives have them (Eg. E. coli) o 2 types in salmonella  SPI-1 (injects Sop E2, SipA, SipC) • Gastroenteritis • Pro-inflammatory cytokine release • Macrophage apoptosis • Invasion of epithelial cells • SP1-1 injects bacterial proteins into host cells that cause actin rearrangement and ruffling which allows phagocytosis  SP2 • Systemic disease • Macrophage cytotoxicity—slow process • Induced inside host cells • Allow for survival and replication in mice macrophages • Used for intracellular survival since SPI-2 avoid lysosomal fusion within vacuole • Replicates inside this vacuole and then released from M cells to transfer to intestinal peuyer’s patches where it causes inflammation, diarrhea • Diagnosis and treatment o
More Less
Unlock Document

Only page 1 are available for preview. Some parts have been intentionally blurred.

Unlock Document
You're Reading a Preview

Unlock to view full version

Unlock Document

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit