Lectures 13-Final Flashcards
(215 cards)
A type of symbiosis where both species benefit but do not depend on each other for survival
Cooperation
How do viruses save genome space
1)Overlapping genes
2)No introns
What happens to the cell once shigella invades?
1)Uses T355 effector to control gap junctions
2)Hijack Connexin 26 gaps junction hemichannels releasing ATP from the host
3)Excess ATP is used to fund bacterial invasion
4)Shigella generates IcSA effector to recruit actin that propels it around the cell
Found on the surface of Helper T cells that recognize the MHC2 +antigen complex
T cell receptor
Shigella testing in labs
1)Monkey-expensive and ethically challenging but gives similar results to humans
2)Mice are not susceptible to infections
3)Rabbits can only infect closed off segments of intestinal tract
4)Young guinea pig below 250g
the a.a sequence in this regions gives the antibody variability/ specificity
Variable region
Category B bioterrosim agents
Moderately easy to disseminate, moderate morbidity and mortality rates ex.Salmonella and E.coli
Biosaftey labratory levels
1) Level 1, Lab bench and sink
2)Level 2, BSL 1 facilities and autoclave avalible, negative air pressure
3)Level 3, BSL2 and self closing doors, away from access corridors, separate exhaust systems, everything is autoclaved and serum testing is done
4)Level 4, BSL 3 and shower to exit, change clothes in and out, separate building or zone, decontamination systems, separate ventilation
Steps in diarrhea generation by E.coli via serotonin
1) Alteration to serotonin functions
2) works on the nervous system of the intestine, the
enteric nervous system.
4 tenants of clonal selection theory
1)Each body must contain a pool of lymphocytes that posses a range of antigenic binding sites
2)Lymphocytes that reacts with self molecules are eliminated early in development
3)Each lymphocyte must have a receptor for a specific antigen
4)Each B cell clone can secrete antibodies to the antigen that it binds for
small, colorless cell fragments in our blood that form clots and stop or prevent bleeding made in our bone marrow.
Platelets
Reticulitermes and trichonympha
Live in the hind gut of termites and degrades cellulose, Trichonympha has its own symbiote Reticulitermes that is able to fix nitrogen
How do bacteria become infected with bacteriophages
1)Lytic infection
2)Lysogenic infection
Small peptides that are secreted by white cells to stimulate and activate other white cells
Interleukins
WBC responsible for allergic reactions
Basophils and Eosinophils
Virus naming method
Order-Virales
Family-Viridae
Subfamily-Virinae
Genus-Virus
Type species- Virus with a space between virus and name
6 category A select agents
1)Bacillus anthracis
2)Clostridium botulinum toxin
3)Variola major virus
4)Filoviruses and arenaviruses
5)Yersinia pestis
6)Francisella tularensis
Protein in influenza that binds silalic acid
haemagglutinin
Disulfide bridge linking the two heavy regions together
Hinge region
Virus composition and size
Virus:10nm and few to several hundred genes
Composed of DNA or RNA and a protein coat that binds nucleic acid,Lipid membrane and virally encoded enzymes
Lysogenic infection
1)Phage DNA infects the host bacteriam and the DNA is incorporated into the the host chromosome
2)Phage DNA replicates in the bacterial chromosome and DNA excision may occur. Then the lytic cycle begins
How is EHEC toxin delivered
1) On the bacterial surface
2) Directly delivered into the host cell cytoplasm.
3) Secreted (Toxins)
Francisella tularensis invasion of cells
1)Enters via a Francisella containing vacuoles for 30-60 minutes
2)Vacuole breaks in the cytoplasm of the host cell occupying the entire cell cytoplasm
Uses a type 6 secretion system
Three R’s of specific immunity
1)Recognize, distinguish between self and foreign molecules
2)Respond, respond to eliminate pathogens with lymphocytes
3)Remember, immunological memory stored in wbc that remember first exposure