Get 2 days of premium access
Study Guides (370,000)
US (220,000)
LSU (10,000)
BIOL (3,000)
Study Guide

BIOL 4215- Final Exam Guide - Comprehensive Notes for the exam ( 80 pages long!)


Department
Biological Sciences
Course Code
BIOL 4215
Professor
W.Doerrler
Study Guide
Final

This preview shows pages 1-3. to view the full 80 pages of the document.
LSU
BIOL 4215
FINAL EXAM
STUDY GUIDE

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

Salmonella
Gram negative pathogen often associated with outbreaks associated with
contaminated food
typhimurium still virulent in humans
but symptoms are not as bad
salmonella is often acquired as a
food pathogen; accidentally ingest
and it goes to stomach where a few
may survive and go to small
intestine.
Invades into M cells where inv locus
is necessary for virulence
The barrier of the small intestine works really well most of the time
Salmonella can bind and cross epithelial cells
CDC says outbreaks due to “bearded dragons”, turtles, Tyson chicken etc.
also other reptiles- have strong defenses against salmonella
Cloning and molecular characterization of genes whose products allow
Salmonella typhimurium to penetrate tissue culture cells (Jorge E. Galan)
This is the inv locus paper
Inv A turned out to be homologous to a gene called FlhA, a gene involved
in assembly of flagella
oThe link between invasion and flagella
The invA gene is clustered on a chromosome in
a pathogenic island SPI1 and SPI 2
Flagella in addition to encoding movement
properties, it is attached to a protein secretion
apparatus that anchors it into the envelope of the
cell.
The proteins that make up the filament are secreted
through the part in the envelope
Salmonella and other virulent strains have
taken the flagella secretion apparatus and
made it into an injectosome
Salmonella proteins are then injected into the cytoplasm of the host
cell
Salmonella injectosome is made up of a series
of rings
Series of proteins that repeat themselves
1
find more resources at oneclass.com
find more resources at oneclass.com
You're Reading a Preview

Unlock to view full version

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

All the rings span the entire envelope then you
have the needle portion that goes through the
center of the rings reaching from cytoplasm to
extracellular portion
Visualization of the type III secretion sorting platform
of Shigella flexneri
Minicell is a modified version of shigella which
reproduces symmetrically and one of the daughter
cells doesnt have the DNA; it has the
proteins and such
In the pic you can see all of the
layers and where the injectosome spans
Effector proteins move through the injectosome
Effector proteins affect virulence
Fusion proteins are using ligase to attach
different DNAs
They attached a polypeptide to GFP a
flueorescent protein also folds readily
once synthesized.
The polypeptide usually passes through the injectosome but with GFP it
jams it and then they took pics
They found a direct tunnel going from cytoplasm of cell out of the cell
For a protein to go through it has to unfold completely
Once they get into host cell they then have to refold
The type three secretion machinery is used by a variety of plants and animal
pathogens:
Salmonella enteriditis
Pathogenic E. coli
Shigella flexneri animal pathogens
Pseudomonas aeruginosa
Yersinia pestis
Erwinia amylovora
Ralstonia solanacearum plant pathogens
Xanthomonas oryzae
Pseudomonas syringae
Some pathogens that use a Type III secretion system:
Salmonella enterica: proteins stimulate host cell membrane ruffling and
entry into cells via processes called pinocytosis. Cells proliferate
intracellularly
Yersinia pestis- Yop proteins inhibit phagocytosis and host cell
activation of inflammatory response via transcription factor NF-kB.
Bacteria proliferates extracellularly.
Enteropathogenic E.coli attachment to host cells
2
find more resources at oneclass.com
find more resources at oneclass.com
You're Reading a Preview

Unlock to view full version