Lectures 13-Final Flashcards
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
Creatures that lack any type of microbes in or on them
Gnotobiotic animals
Variable region in the larger portions of the antibody
Heavy variable region
How do gram negative bacteria infect cells?
Directly delivers toxins into the host cell cytoplasm via an injection
PAMPS
Pathogen associated molecular patterns,molecular motifs associated with pathogens such as bacteria and viruses
Clonal selection theory
a clonal expansion of the original lymphocyte occurs when the original lymphocyte is activated by binding to the antigen; however, any clone of the activated lymphocyte with antigen receptors specific to molecules of the organism’s own body (self-reactive receptors) is eliminated
Shigella bacteria properties
G-, Anaerobic, intracellular pathogen, actively invasive, controls the cell cytoskeleton
Fusogenic proteins
Protein that allows for viruses tho enter host cells via endocytosis or membrane fusion with host
Why are Linear DNA transformations rare in nature?
Only 1% of bacteria can uptake naked DNA and the DNA provided has to be from a closely related species
How is a bacterial strain made competent
1)CaCl2 treatment causing pore formation in the membrane
2)Electroporation->exposes the cell to a transient electric feild
3)Biolistics->Shoot at high velocity inert bands coated with DNA
Heritable features that decrease the probability of pathogen success
Nonspecific immunity
Specific immunity types
1)Natural active- due to individuals life time exposure to foreign material
2)Natural passive- Transfer of maternal antibodies via the placenta or colotrum
3)Artificial active- Vaccination
4)Artificial passive-administer antibodies to a specific material
Found on the surface of the cell wall and membrane, they recognize specific DNA sequences and allow for linear DNA uptake
Competence protein
Discovered the bacteriophage
William Twort,
Examples of antigens
1)Outer membrane of G- bacteria
2)Viral spike protein
3)LPS
a state when a cell, usually bacterial, is temporarily partial diploid as result of DNA transfer processes like conjugation
merozygote
Specific immunity response to foreign material
1)Production of specific antibodies that bind the foreign material
2)Proliferation and differentiation of a subset of white blood cells from leukocytes to lymphocytes
How does Internalin B invade cells?
Uses the endocyitc machinery of cells by binding to Met it gets internalized by clatherin at the site of contact
Mary Mallon
First person to be identified as a chronic carrier of Salmonella
How to strengthen or weaken phagocytosis
Weaken- capsule external to the cell wall
Strengthen- coating foreign body with serum proteins (Opsonization)
Newly added DNA that can either incorporate into the host genome or can be degraded by the host enzyme, DNase
exogenote
PRRs
Cause signalling receptors bound to trigger a signalling cascade leading to secretions from macrophages that attract more WBC’s to the foreign material
How does colon tissue avoid infection?
1)Perastalsibility of the intestine,moving smooth muscles
2)Mucous secretions and flow decrease attachment chance
3)Epithelial sloughing
Yersinia pestis
Gram negative, rod shaped bacteria that causes black death. Trasnimted through infected fleas or from inhalation of air from infected person.
Cell to cell infection of shigella
1)Targets tricellular junctions of cells for efficeint cell to cell spreading
2)Uses Tricellulin to attack tricellular junctions and fuse with adjacent membranes
3)Also uses clatherin mediated endocytosis to move cell to cell
B-lymphocytes
B-cells, form 30% of lymphocytes and mature in bone marrow and fetal liver, secrete antibodies and attack viruses, bacteria, and bacterial toxins
Plasmid
Extra chromosomal dsDNA, circular, replicate autonomously fro the host chromosome. Encode up to 30 genes that confer a selective advantage
Disease caused by shigella
Bacillary Dysentery
How is virulence determined?
1)Comparative ease an organism is transmitted to other hosts
2)Invasivness- ability to enter host and spread
3)Adhesiveness-ability to adhere to cells
4)Toxigenicity- ability to produce toxic byproducts
Why is Francisella tularensis considered a type a pathogen?
Causes the overrun of the entire medical system and can be made drug resistant
Francisella tularensis
Gram negative rod shaped bacteria that infects through igestion,inhalation, eyes and urethra, and bites from vectors. Enters epithelial cells and phagocytic cells, via clatherin mediated endocytosis for epithelial and phagocytes by general phagocytosis
How does Ebola virus invade the body
Uses membrane ruffling to get into the cell via actin and actin associated proteins but Zaire ebola virus uses clatherin to enter cells
H5N1
Bird blu, single stranded RNA virus with a helical capsid and envelope. It’s DNA is contained in 8 different segments that must unite together to complete it’s life cycle
Shigella symptoms and duration
Duration:4-7 days
Symptoms:Painful bowel movements,cramps,nausea, loss of appetite, bloody diarrhea and high fever.
Proteins used by listeria that triggers the internalization of Listeria into the cell.
Internalin
What happens to Listeria once it has been internalized into the cell?
1)Forms a vacuole that breaks shortly after entry
2)Listeria is now free to move in the cell using actin tails. Due to the lack of a vacuole surrounding it, lysosomes are incapable of fusing and destroying the bacteria
Macrophage like cells that sample and engulf foreign material
Dendritic cells
Salmonellosis pathology
Occupies: GI tract
Incubation:8-48 hours
Symptoms: Headache, cramps, diarrhea, high fever, nausea, vomiting, appetite loss
Duration:4-7 days
a substance that is harmful to your digestive system. It is produced by certain bacteria. Enters your stomach and intestines if you eat contaminated food or water ex.Cholera and Salmonella
enterrotoxin
Protein that cleaves sialic acid to prevent viral recapture
Neuraminidase
extra-chromosomal DNA elements that are capable of horizontal transmission. Required to assemble the pilus, marked with an F factor
Conjunctive plasmid
Responsible for bacterial entry into non phagocytic cells using Human E-cadherin as the receptor
Internalin A
Fragment that binds to cells and allows antibodies to activate the immune system
Fc fragment
Symbiosis
The association of 2 or more dissimilar organisms together
concluded that cells from the hen’s tumor contained an infectious substance, a virus, that transmits cancer. Fufilling Kochs postulates
Peyton Rous
The B cell differentiation types
1)Plasma cell which secrete antibodies
2)Memory cells long circulating time in the system and requires T cells help
Lymphoid tissues that closely associate with skin. Confers microbes to the superficial layers of the skin to prevent access to the blood stream
Skin associated lymphoid tissue (SALT)
Features of viruses
1)Simple acelluar structure
2)DNA or RNA but never both
3)Obligate intracellular parasites, a host is required for reproduction
Why does our body cause diarrhea
to rid the bacteria from
our system and remove much of the E. coli as possible
2)Causes dehydration,loss of ions,hemorrhage and death
Legionella
Cause legionares disease, likes stagnant water. Legionella secrete proteins into the macrophage to prevent phagosome maturation and recruits ER membrane to the phagosome. This protects the legionella from lysosomal attacks in the ER phagosomes and replicates inside of it.
Diseases caused by Salmonella
Salmonellosis and Typhoid Fever
Showed that viruses were mainly made of nucleic acid and proteins
Stanley Bowen and Prairie
remove foreign debris and particles that have come from the hepatic portal system when passing through the liver
Kupffer cells
How does G+ pathogens infect cells?
Uses surface proteins to invade the cells and control them
Names for
Redness
Heat
Pain
Swelling
1)Rubor
2)Calor
3)Dolor
4)Tugor
Inanimate material that can transmit pathogens ex. surgeon tools
Vehicle
What is this capsid shape
Isohedral
RNA virus types
1)Positive single strand
2)Negative single strand
3)Double strained RNA
4)Retroviruses
Lytic infection
1_Phage contacts bacteria and infects with phage DNA
2)Phage DNA is transcribed and replicated while host DNA is degraded
3)New phage particles are assembled and Lyse the cell
Steps in viral budding from a host cell
1)Viral proteins are inserted into the host plasma membrane
2)Nucelocapsid will bind to inner surface of the plasma membrane
3)Viral proteins will collect at the site of viral contact and host proteins are excluded
4)The plasma membrane buds this forming the viral envelope
5)A virion is released
Heavy chain types and their names
1)α->IgA
2)Y->IgG
3)E->IgE
4)δ->IgD
5)u->IgM
MALT
Mucous associated lymphoid tissue Lymphoid tissue closely associated with mucous membranes
protomers
Protein monomers that self assemble into the capsid via non covalent bonds
How does Listeria gain its actin tail?
Surface proteins on listeria recruit ActA to bring and build the actin tail
Variable region in the smaller arm of the antibody
Light variable region
Virally induced lesion
Pock
E.coli transmissions, duration, effective dose and symptoms
Transmission:Contaminated food or person to person
Duration:7 days
Effective dose:10-100
Symptoms:Hemolytic uremic syndrome, Bloody diarrhea and abdominal cramping
organized structures that support immune responses ex. Spleen, bone marrow
Lymphoid tissue
Positive symbiosis types
1)Mutualism
2)Cooperation
3)Commensalism
Main outcomes of complement activation
1)Opsonization, which increases the probabiliy of phagocytosis
2)One complement protein acts as a chemokine and recruits WBC
3)Several complement proteins act coordinate to form a pore in a foreign cell and lyse it
Steps for a pathogen to cause an infectious disease
1)Maintain a reservoir
2)Be transported to and enter a suitable host through a suitable route
3)Adhere to colonize,invade host tissue
4)Initially evade host defesnes
75kDa chain that forms the antibody
Heavy chain
Developed a porcelain filter that could eliminate Bacteria
Chamberland
Features of IgG, Y
80-85% of serum, 21 days in the blood, placental transfer, bind bacteria, viruses, toxins, haptins and carriers
a clear-to-white fluid made of: White blood cells, especially lymphocytes, the cells that attack bacteria in the blood and body tissues.
Lymph
Marburg virus
1 species similar to ebola but with no cross protection, genome is 19.1 kb in length with a 25% mortality rate
T-lymphocytes
T-cells, form 70% of all lymphocytes and mature in the thymus, attack virally infected cells, cancer cells, transplant tissue, any foreign cells.
Differences between specific and non specific immunity
1)Discrimination-distinguish between self and nonself
2)Diversity-recognizes trillions of non self cells
3)Specificity-distinguish specific molecular structure with no cross reactivity to similar but non identical structures
4)Memory- congers the ability to mount a strong er and faster response upon future exposures
A bacterial strain that donates its genes with a high frequency to a recipient during the conjugation because the F+ factor is integrated into the bacterial chromosome
HFR strain
Safety equipment and BSL
1)No barriers needed, personal protective equipment
2)BSL1 and Biological safety cabinets
3)BSL2+ Stricter protocols
4)Pressurized suits, and glove boxes
Valence
Number of antigenic determinants possessed by an antigen
Links the heavy and light chain together as well as forms the hinge region
Disulfide bridge
How do T cells recognize foreign antigens?
The antigen needs to be digested by a different cell and presented to the surface of the T-helper cells by antigen presenting cells such as B cells
Examples of chemical barriers
Lysozymes, found in WBC and epithelial cells they bind to and lyse foreign cells. Are activated by compliment protein cascade
Steps in diarrhea generation by E.coli via Aquaporins
Alteration of water charmed (aquaporin [AQP])
2)Use EspF and ESPG
3)Removes AQP2 and AQP3 from the membrane
Protein used by listeria to invade hepatocytes by recruiting clatherin
Internalin B
5 species of ebolavirus
1)Zaire ebolavirus
2)Sudan Ebolavirus
3)Tai Forest ebola virus
4)Bundibugyo ebolavirus
5)Reston ebolavirus, does not cause human disease
Infectious diseases that can be transmitted from animals to humans ex.hanatavirus
Zoonoses
Types of Negative symbiosis
1)Predation
2)Parasitism
3)Amensalism
4)Competition
Shigella infection pathway
1)Uses a type 3 secretion sytem in inject effector proteins into the cell
2)Uses membrane ruffling to invade host cells
how does the EHEC toxin affect cells
Modifies
1)Cytoskeleton
2)organellar functions
3)cellular structures
4)channels
5) signalling pathways
Steps in diarrhea generation by E.coli via ion channels
1) Alteration of ion channels
2) Shiga toxins attach to receptors
3)Cause intracellular signalling
cascades that alter the
functions of many different ion channels.
4) Ions and water and released
from the cells
Run down on Ebola
Incubation 2-21 days, infectious dose 1-10 days, causes fever, headache, joint and muscle paint, bleeding and 80-90% fatal. Infects the endothelial cells, mono nuclear phagocytes and hepatocytes
Observed changes to cells due to viral replication depending on virus and cell type
Cytopathic effect
Lysozyme
Cleaves cell walls Nam-Nag bonds in peptidogylcan and is produced in tears and sweat
Category C bioterrosim agents
Emerging pathogens that could be engineered for mass dissemination with potential for high morbidity and mortality rates with major impacts. Ex.Hanata virus and MRSA
Features of IgM, μ
10-15% of serum antibodies, 10 days in the blood, used in agglutination
Difference from retroviruses and RNA viruses
RNA viruses use RNA polymerase to replicate where as retroviruses need reverse transcriptase to copy the RNA to DNA
Receptor protein for Internalin A
Human E-cadherin
Examples of phagocytosis
1)Blood-Monocytes, polymorphonuclear leukocytes
2)Tissue- monocytes, resident macrophages,polymorphonuclear leukocytes
Developed the Bacteriophage Plaque assay
d’Herelle
Antigen binding fragment, proteins that form part of the antigen recognition site
Fab Fragment
How do antibodies bind to diverse antigen structures?
1)Exon shuffling in antibody gene sequences
2)Differential slicing of antibody genes
3)During differentiation B cells undergoes a high level of somatic mutations for immunoglobulins
Filoviruses
Viral hemorrhagic fevers, caused by single stranded, negative sense RNA virus that damages the vascular systems and causing hemorrhaging. Transmitted by bats and Rodents ex. Manburg virus and Ebola
Conjugative pili allow for the transfer of DNA between bacteria, in the process of bacterial conjugation
Sex pilus
A living organism that transfers an infective agent between hosts ex. ticks
Vector
Major histocompatibility complex 2
Cells capable of presenting antigens to T cells such as B cells, macrophages, dendritic cells
Shigella types
1)Shigella dysenteriae
2)Shigella flexneri
3)Shigella Sonnei
Conjugation of an HFR strain with a F- strain
1)Pilus attaches the cell and pulls them close
2)New strain is synthesized by a rolling circle replication, host chromosome is transferred first
3)Donor and Host cells recombine, F factor is not inserted
Serum immunoglobins
Antibody
Features of IgD, δ
0.2% of serum antibodies, 3 days in the blood, atttached to the surface of b-lymphocytes
Bio-terrorism
The intentional or threatened used of viruses,bacteria,fungi, or toxins from living organism to produce death or disease,to humans animals or plants
Factors affecting outcome of host vs disease
1)Innoculum size
2)Location of infection
3)Health of host
4)Virulence of pathogen
Causes Salmonellosis
Salmonella Typhimurium and Salmonella enteritidis
Viral entry of membranes
1)Clatherin is recruited to entry site
2)Bud forms and a clathein coated vesicle is formed
3)Endosome is acidified with H+ ions leads to nuclear capsid being release
Steps in diarrhea generation by E.coli via tight junctions
1) Breach of tight junctions
2) uses bacterial effector proteins :EspF, EspG , Map ,
Spike proteins
proteins that trigger an immune response
ex.Influenza
1)Hemagglutinin:links and clumps RBC
2)Neuraminidase: The enzyme breaks down the glycosidic bonds in glycoproteins, glycolipids, etc. to release neuraminic acid.
A zone of clearing caused by virally induced lysis
Plaque
T cell independent antigen
Antigen simulated B cells that produce antibodies. Antigen receptors on the B cell surface is capped after endocytosis and activates expansion of that B cell clone and the production of plasma cells using IgM
Properties of the Salmonella bacterium
G-, Intracellluar pathogen, actively invasive, controls host cytoskeleton, injects effector proteins to induce membrane ruffling to enter cells
25kDA peptides that form the antibody
Light chain
Insertion sequence
small DNA segments capable of moving (transposing) within and between replicons. Allows plasmid integration into the chromosome
The original complete genome of a bacterium, before addition of new genetic material (an exogenote) from a donor by the process of genetic recombination or by genetic engineering
Endogenote
An infected individuals who is a potential source of infection for others
Carrier
Where does Yersinia pestis attack?
Attacks the blood or lymph tissues. Replicates inside of phagocytes via a type 3 secretion system called YOPS
myeloid cells, which includes monocytes, macrophages, neutrophils, tissue dendritic cells and mast cells
Professional phagocytes
Receptor for Internalin B
Hepatocyte growth factor receptor (Met)
Type of symbiosis where one species benefits while the other species is not affected
Commensalism
A molecule that is NOT immunogenic on its own but when bound to a carrier protein (from the host) forms an antigen ex.Penecillian
Hapten
Bacteriophage
Phage injects its own phage DNA into the recipient cell and new phages will be generated eventually lysing the cell
Examples of Biosaftey levels and viruses
1)Cultured cells, non pathogenic microbes
2)Pathogenic E.coli Salmonella species
3)Francisella tularensis
4)Ebola Virus
How does E.coli cause diarrhea
1)injected effector
2) Shiga toxin
Conjugation by F factor
1)Donor chromosome with F+ factor moves towards F- cell
2)Pilus shortens and brings the two cells together
3)A protein complex called relaxosome cuts the DNA to be transferred at the origin of transfer
4)Accessory proteins of the ribsome are released but remains attached to the DNA and coupling with a together factors being it to the export region of the pilus
5)Relaxase is used to join the two ends of DNA and DNA is replicated
6)The F- cell is now a F+ cell
A deviation of the normal structure or function of any part of the body that is manifested by a characteristic onset of symptomes
Disease
Diffrence between virus and plasmid
Unlike viruses, which encase their genetic material in a protective protein coat called a capsid, plasmids are “naked” DNA and do not encode genes necessary to encase the genetic material for transfer to a new host
Transduction
Transfer of genes between bacterial or archeal cells via viruses
T cell dependent antigen
Requires both B and T cells to produce a strong immune response, uses against viruses, bacterial toxins etc. IgA. IgG, IgE plus T-helper cells
Virus without a lipid membrane
Naked virus
Parasite types
1)Protozoans
2)Worms
A type of symbiosis where both species benefit and depend on each other for survival
Mutualism
a network of delicate tubes throughout the body. It drains fluid that has leaked from the blood vessels into the tissues and empties it back into the bloodstream.
Lymphatic system
Mechanism of transduction
1)Host DNA is degraded
2)Some phage accidentally incorporate host DNA and can infect other bacterium
3)Recombination occurs
RNA Virus strand types
(+)= Sense strand mRNA immediately transmitted to viral proteins
(-)= Antisense strand, a complimentary RNA of (+) must be made before viral proteins can translate
Generate plasma cells and memory cells
BCDF’s or B cell differentiation factors
E.coli diseases
1)Intestinal disease
2)Urinary Tract infections
3)Neonatal meningitis
E.coli pedestals
They cause actin restructuring and polymerization within the host cell to create an actin-rich protrusion below the site of adherence, termed the pedestal.
filter substances that travel through the lymphatic fluid
Lymph nodes
Shiga toxin
A sub unit toxin that bins to ribosomes inhibit protein synthesis leading to diarrhea containing blood,mucus, and pus
Dangers of H5N1
Mortality Rate:50% lethality rate
High antigenic drift rate
Spreads quickly and comes form chicken facotries
Herpes simplex virus infection of cells
1)Nucelocapsid enters cytosol
2)Viral dsDNA is injected into the nucleus
3)In the nucleus the viral genome circularize and early genes are transcribed
4)Viruses bud from nuclear membrane and are release by exocytosis
Found that filtered extracts from tobacco could transmit disease to other plants leading to discover of mosaic virus
Ivanovsky and Beijerinck
Ways in which E.coli can trigger diarrhea
1)Breach fight junctions
2)Alterations of water channels (Aquaporins)
3) Alteration to serotonin functions
4) Alteration of ion channels .
Transformation
Uptake of naked DNA in the form of linear DNA segments or Plasmid DNA
Basic background of Salmonella infectious history
Transmission: Person to person, animal to person or through contaminated food
Infective dose:100-1,000,000,000 organisms
Source:Intestinal tract of birds or other animals
Antibody responses
1)Precipitation of soluble antigens
2)Neutralization of foreign material reducing infectivity
3)Complement fixation, cell destruction
4)Agglutination insoluble antigens clump together
5)Opsonization, Fc receptors call for macrophages to destroy cells
Salmonella infections
1)Injects effector protein using type 3 secretion system
2)Gains entry to cells by controlling actin
3)Causes membrane ruffling
4)Enters cell and is found in a SCV
5)Blocks lysosomes
6)Survives and replicates in the SCV
7)Kills host cell
Why can’t microbes invade the skin barrier?
1)Good phsyical barrier
2)Inhospitable environment, Low Aw, keratenized layer, constantly shedding, salty, Lysozymes
discovered avian leukosis virus (ALV), the first known tumor virus.
Ellermann and Bang
Living space of Salmonella once it invades, protects from lysosomes consumption
Salmonella containing vacuoles
Listeria basic background
Disease: Listeriosis
Caused by: Listeria monocytogenes
Transmission: Contaminated food
Symptoms: Nausea, diarrhea, Muscle aches, fever, start after 30 days
Nervous system symptoms: Headache, stiff neck, confusion, loss of balance, convulsions.
Pregnant women: Lead to miscarriages and infection of new born
Infective dose:100-1000 organisims
A type of symbiosis where one species kills the other
Amensalism
Steps in phagocytosis
1)Binds to molecules on pathgoen surface via specific receptors
2)Internalization into phagosome
Virus capsid shapes
1)Helical
2)Isohedral-20 sided
3)Complex-able to change shape
Mechanism for Internalin A invasion of intestinal cells
Since old cells are at the top of the villi when the old layer is shed during extrusion it exposes E-cadherin receptors allowing Listeria to bind and invade cells
Physiological effects of lacking microbes
1)Thinner gut walls
2)poorly developed lymphoid tissues
3)More susceptible to disease
4)No cavities
5)Require high vitamin B and K since commensels produce this
5 E.coli types
1)EHEC-Enterohemorragic
2)EPEC-Enteropathogenic
3)ETEC-Enterotoxigenic
4)EIEC-Enteroinvasive
5)EAggEC-Enteroaggrevative
Branches of the vertebrate immune system
1)Humoral->antibodies are secreted by B-lymphocytes
2)Cell mediated-> Cytokines are secreted by T-lymphocytes
E-cadherin
Intercellular junction protein
Disease caused by Francisella tularensis
Causes tularemia a disease which causes flu like symptoms and skin lesions after 2-10 days
tailors its attack to a specific antigen that was previously encountered. Its hallmarks are its ability to learn, adapt, and remember.
Specific immunity
Salmonella
host endosomal vesicles are associated with Salmonella effectors. Effector-positive vesicles continuously fuse with SCV and SIF membranes, providing a route of effector delivery by translocation, interaction with endosomal vesicles, and ultimately fusion with the continuum of SCV/SIF membranes
a type of virus that inserts a DNA copy of its RNA genome into the DNA of a host cell that it invades, thus changing the genome of that cell.
Retrovirus
Sources of undifferentiated lymphocytes
Bone marrow
Virus vs Virion
Virus:Replicated intracellular form
Virion:Extracellular infections particle
Limits on host range for a virus
1)Limited by the specific receptors available on the host cell
2)Non permissible for viral replication
How do you grow a virus in lab?
1)Embryonic chicken eggs are injected with virus
2)Cell culture mono layer derived from a specific cell type
An antibody generator known as an immunogen that is a foreign molecule that will elicit antibody production
Antigen
Primary vs secondary response of immune system
1)Primary has longer latent period allowing for full life time to occur
2)IgM response is less in the secondary response but IgG and total antibodies is significantly higher
3)Log phase is significantly steeper
4)Plateau phase is longer
a system used to classify viruses based on their manner of messenger RNA (mRNA) synthesis.
Baltimore virus system
Route of infection for listeria
1)Bacteria is ingested
2)Transported to intestine and crosses the intestinal barrier
3)Enters lymphatic system into the blood
4)infects and replicates in the spleen and liver
5)Jumps back into the blood stream and moves to the brain or placenta
a group of amino acids or other chemical groups exposed on the surface of a molecule, frequently a protein, which can generate an antigenic response and bind antibody.
Epitote
Features of IgE, ε
0.0005% of serum antibodies, last 2 days in the blood, binds to mast cells and activates them as well as fights parasites and worms by increasing gut motility
A general term used to indicate any soluble protein or glycoprotein release by 1 cell population that acts as an inter cellular mediator or signalling molecule.
Cytokines
Features of IgA, α
10% of serum antibodies, 6 days in the blood, secretion at mucous surfaces
Examples of physical barriers
1)Lactoferrin: an iron-binding glycoprotein found in human and bovine milk that has powerful immune boosting effect
2)Mucus associated lymphioid tissue(MALT) found in but and urogenic tracts
3)Mucocilliary elevator, traps microbes larger than 10um in hair and cillia
4)Mucocilliary blanket, traps microbes less than 10um in the lower respiratory system
Viral envelope
A lipid bi layer that surrounds the nucleocapsid derived from the host plasma membrane, ER, or golgi
Category A bioterrosim agents
Easily disseminated or transmitted person to person with high mortality rate, potential for major health impacts, causes public panic and social disruption and requires action for public prepardness
Nonspecific barriers to potential pathogens
1)Physical barriers
2)Chemical barriers
3)Phagocyotisis
Mast cell
Cell packed with histamines and other pharmacologically active substances
Purpouse of Diarrhea for pathogens
Spreads the virus into the enviroment
DNA sequence that contains 1 or more strucutral genes that encode for the regulation of a gene
Operon
A type of granular white cell
Lymphocytes
