Chapter 16: Host Microbe Interaction Flashcards
Establishment of growth of a microorganism on a surface
Colonization
A lipopolysaccharide component of Gram-negative bacteria; lipid A is responsible for the toxic properties
Endotoxin
Difference between opportunistic and primary pathogens
Opportunistic only affect sick people
Primary in healthy
A symbiotic relationship were both partners benefit
Mutalism
Relationship between 2 organsim in which 1 partner benefits and the other is unaffected
Commensalism
Are all pathogens parasitic
Yes
An imbalance in the microbiome is called
Dysbiosis
The ability of a pathogen to overcome body defense and cause disease
Virulence
Number of microbes sufficient to establish an infection is expressed as
Ld50
Progression of infectious disease
Incubation
Illness
Convalescence
- Prodromal phase is also included what is this and where does it belong
Before illnesss
It is a general feeling of MALAISE (general not feeling well)
Acute illness caused by an inflammatory response that results when pathogens or their products circulate in the blood stream
Sepsis
Circulation of toxins in the blood
Toxemia
Circulation of virus particles in the blood
Viremia
Criteria used to determine the cause of an infections disease by culturing the agent and reproducing the disease
Kochs postulates
Production of toxins
Colonization of mucos membranes
Invasion of host tissues
Invasion of host tissues followed by toxin Production
Are what?
Pathogenic mechanisms to invade a healthy host
Iron binding substance produced by bacteria to scavenge iron
Siderophore
This Phage like mechanism called ________ is used by bacterial cells to inject gene products directly into host cells
Type III secretion system
Characteristic mechanism of engulfment that some bacteria induces by triggering rearranging the cells actin
Membrane ruffling
2 methods bacterial pathogens use to infect body through the mucus membranes
Direct uptake
Exploiting Antigen Sampling Process
This is the process a bacterial cell injects an effector protien into host cell causing it to endocytoize the pathogen
Direct uptake
2 parts of the antibody
____ binds to the antigen
_____ functions as a Red Flag
Fab
Fc
How does the complement system lyis foreign cells
Membrane attack complexes
Bacteria that avoid being killed by the complement system are called
Serum resistant
This enzyme cleaves a class of antibodies found in mucus and other secretions
IgA protease
Mechanisms for avoiding antibodies include (3)
IgA protease, antigenic variation, mimicking host cells
Vaccination against toxins like tetanus & diphtheria are called
Toxoids
If a person injest toxins this can be reversed by
Antitoxins
These toxins have 2 parts: 1st part is the toxic part
2nd part is the binding part
A-B toxins
These antigens bind to the MHC II molecule on antigen presenting cells and t cells, causing false recognition. This produces a cytokine storm which maybe deadly
Superantigens
3 types of ExoToxins
A-B, membrane damaging, superantigens
Certain antibodies produced in response to an infection can bind to the bodies own tissues promoting an autoimmune response.
These are called
Cross-reactive antibodies
What are Pattern Recognition receptors looking for
Viral nucleic acids
Multinucleated body formed by cell fusion
Syncytium
Firmicutes and bacteriodsetes are commonly represented phyla in the _____ of adults
Intestinal tract
4 Roles of the human microbiome include
Excluding pathogens & Priming adaptive immune system against pathogens
Tolerance to non harmful substances
Aids in digestion
Produces vitamins
_____ provide a foundation for determining the cause of infections disease
____ provides a foundation for identifying virulence factors that contribute to disease
Kochs postulate
Molecular Kochs postulate
Rapid turnover of pili, antigenic variation, and IgA protease allow bacteria to avoid the effects of secretory ____
Iga
____ enable microbes to scavenge iron
Siderophores
Mechanism that allow bacteria to transfer gene products directly into host cells
Type III secretion systems
A protein in the cell walls of group A Streptococci that is associated with virulence
M protein
Capsules, M protein, Fc receptors all serve for this function in pathogens
Avoid recognition and attachment of phagocytes
____ describes bacteria that have a mechanism to avoid the killing effects of the complement system proteins
Serum resistant
Toxins that damage a variety of different cell types
Cytotoxins
Neurotoxins, enterotoxins, cytotoxins are all this type of toxic protein
Exotoxins
A-B is an exotoxin composed of an active subunits ____ and a binding subunit ____
A / B
_____ override the specificity of the T-cell response, causing a cytokine storm
Superantigens
Symptoms associated with (this type of toxin) ____ are due to a vigorous host response .
Lipid A is responsible for its toxic properties
Endotoxin
This combination of the antibody/ antigen complex can cause kidney and joint damage
Immune complex
These fungi are generally opertunistic…..
Saprophytes
____ cause superficial infections of skin, hair, and nails
Dermatophytes
Which type of fungi cause the most serious infections
Dimorphic
Capsules and M proteins are thought to interfere with Opsonization by…
Complement proteins
C5a peptidase enzyme of S. pyrogenes breaks down C5a resulting in…
Decrease accumulation of phagocytes
Is diphtheria an endotoxin or exotoxin
Exotoxin
Endotoxin is
An A-B toxin
Component of Gram-positive bacteria
Can be converted into a toxoid
Heat-stable
Causes T cells to release cytokines
Heat stable
Syncitium
A multinucleated formed cell
The _____ coats group A streptococci (GAS) and acts as the primary antigen and determinant of type-specific immunity. Is essential for GAS virulence, providing antiphagocytic functions critical to survival in human tissues and fluids.
M protein
Dysbiosis
An imbalance of the microbiome
Can normal flora be opportunistic
Yes, in a weakened immune system
How much vitamin K does normal flora provide
10%
Which is more pathogenic
3000 Id 50
200 id 50
200
It is saying that 200 pathogens are required to infect 50 people
Can acute illnesses be latent?
Yes
Toxins: Eaten, don’t need organsim just toxin it produces
Give 2 examples
Staph food poisoning
Botism
Pathogenicity mechanics
Colonization on surface of host and toxin production
Name 2 such pathogens
Diphtheria
E coli 0157 :H7
Pathogenicity mechanics
Invasion of host tissues
Avoid macrophages & detection by antibodies
Name 3 pathogens
TB
Salmonella
Strep pyogenes
Bacteria use Adhesion Proteins on Pili or Fambriae to attach to ____ & _____ receptors
Glycoproteins & Glycolipids
_____ shock (from a bacterial infection). Example: A serious infection complication. Caused by pathogens
_____ shock (from an allergic reaction or asthma attack). Example: An allergic reaction to peanuts
Septic
Anaphylactic
Find the cause of disease
Organsim must be grown in pure culture
Pure culture used to infect new host
Organsim must be found in New Host
Describes this process
Kochs postulate
Finding cause of disease
Virulence factor is cloned and inserted into Non pathogenic strain
Virulence genes expressed during disease
Antibodies against Virulence gene gives host protection
Describes this process
Molecular Kochs postulate
Pathogens deliver _______ to host cells
Destroy microvilli in intestines
Force host cell to take in bacteria
Effector molecules
Mucous membrane penetration
Direct uptake by ____ cells
Or
Exploit antigen sampling by ____ cells
Epithelial
M
Where are M cells located
Peyers Patches MALT
Bacteria can avoid phagocytes by destroying the Complement component that attracts phagocytes with _____ peptidase of strep pyrogenes
C5a
_____ contains Streptolysin O that destroys phagocytes cell membrane
Strep pyrogenes
____ is a strong chemoattractant and is involved in the recruitment of inflammatory cells such as neutrophils, eosinophils, monocytes, and T lymphocytes, in activation of phagocytes
C5a
____ toxins can cause local or systemic infections
____ toxins only produce systemic
Exotoxins
Endotoxins
Endotoxins of the outer membrane of Gram-negative are composed of 2 parts
Lipid A
O polysaccharide
Lipid A & O polysaccharides are found in
Endotoxins of the outer membrane of Gram-negative are composed of 2 parts
Endotoxins are detected by blood from this useless animal
Horseshoe crab
Cross reacting Ab
Attacks heart lining and contributes in ______ an auto immune disease
Rheumatic fever
______ are due to damaged heart valves, where they don’t close properly
Heart murmurs
Viral damage to host
Destroy host cell by …
Viral lytic cycle
Ring worm and athletes foot are examples of…
Dermatophytes
What is Candida albicans
Yeast normal flora
Dimorphic fungi are ____ in the environment but ____ in body
Molds / Yeast
Histoplasma in bat droppings can cause infection of this area…
Lungs
____ is the larger of two elements formed by the cleavage of complement component 3, and is considered an important part of the innate immune system.
It is potent in opsonization: tagging pathogens, immune complexes (antigen-antibody), and apoptotic cells for phagocytosis.
C3b
_____ is a strong chemoattractant and is involved in the recruitment of inflammatory cells such as neutrophils, eosinophils, monocytes, and T lymphocytes, in activation of phagocytic cells and release of granule-based enzymes and generation of oxidants, all of which may contribute to innate immune functions or tissue …
C5a