Term
| Four general classes of virulence factors |
|
Definition
* Adhesins
* Extracellular enzymes
* Antiphagocytic factors
* Toxins |
|
|
Term
| What variable is used to quantify virulence? |
|
Definition
| LD50 (number of microbes needed to kill half of an infected population) |
|
|
Term
| Main difference between primary and secondary virulence factors? |
|
Definition
* Primary factors directly cause disease (eg, exotoxins).
* Secondary factors indirectly convey pathogenicity by facilitating growth, evasion of immune system, etc. |
|
|
Term
| Adhesins are usually what kind of macromolecule (lipis, protein, etc.)? |
|
Definition
| Usually proteins, but can be sugars too |
|
|
Term
|
Definition
| Determine specificity of infection |
|
|
Term
| Main extracellular enzymes that constitute virulence factors |
|
Definition
* Hyaluronidase
* Collagenase
* Coagulase
* Kinases |
|
|
Term
| Purpose of hyaluronidase and collagenase as virulence factors |
|
Definition
| Chew through hyaluronic acid and collagen in extracellular matrix to facilitate invasion and spread |
|
|
Term
| Purpose of coagulase and kinases as virulence factors |
|
Definition
* Coagulase forms clots, making hiding place for bacteria
* Kinases (eg, streptokinase) degrade clot to allow bacterial spread |
|
|
Term
| Major pathogens with coagulase and kinases |
|
Definition
* Staphylococcus aureus
* Streptococcus pyogenes |
|
|
Term
| Major pathogens with hyaluronidase and collagenase |
|
Definition
|
|
Term
| What is the function of staphylokinase? |
|
Definition
| Chews through clots to help spread infection |
|
|
Term
| What extracellular enzymes are used to digest extracellular matrix? |
|
Definition
* Hyaluronidase
* Collagenase |
|
|
Term
| Deadly fungus with antiphagocytic capsule |
|
Definition
|
|
Term
| Composition of bacterial and fungal capsule |
|
Definition
| Non-immunogenic polysaccharides |
|
|
Term
| How do capsules help bacteria evade immune system? |
|
Definition
| Capsules are made of non-immunogenic polysaccharides; ie, they aren't recognized by the host's immune system, so macrophages and neutrophils don't detect them. |
|
|
Term
| What type of virulence factor is Streptococcus pyogenes' M protein? |
|
Definition
|
|
Term
| Leukocidins have what function? |
|
Definition
| Destroy phagocytic white blood cells |
|
|
Term
| Is LPS an endo- or exotoxin? |
|
Definition
|
|
Term
| Bacteria containing LPS are Gram-negative or Gram-positive? |
|
Definition
| Gram-negative (LPS is anchored to the outer cell membrane) |
|
|
Term
| Cytotoxins, neurotoxins, and enterotoxins are examples of endo- or exotoxins? |
|
Definition
|
|
Term
| Where do exotoxins typically act on the host's cells? |
|
Definition
* Cell surface (eg, by inserting a pore)
* Intracellularly (eg, by interfering with metabolism) |
|
|
Term
| Inflammation and immune responses are typically in response to endo- or exotoxins? |
|
Definition
|
|
Term
| Main difference between endo- and exotoxins |
|
Definition
| Exotoxins are secreted by the pathogen; endotoxins (ie, LPS) is part of the pathogen's structure |
|
|
Term
| Etiologic agent of typhoid fever |
|
Definition
|
|
Term
| Etiologic agent of salmonellosis |
|
Definition
|
|
Term
| Do pathogens usually have one or several virulence factors? |
|
Definition
|
|
Term
| How is Staphylococcus aureus transmitted? |
|
Definition
|
|
Term
| Is S. aureus Gram-positive or Gram-negative? |
|
Definition
|
|
Term
| Species of Staphylococcus that is normal flora of nose |
|
Definition
|
|
Term
| S. aureus is responsible for common infections of what areas? |
|
Definition
|
|
Term
| Staphylococcus virulence factors |
|
Definition
Enzymes
* Coagulase
* Staphylokinase
* Lipase
* Beta-lactamase
Antiphagocytic factors
* Polysaccharide slime layer
* Protein A
Toxins
* Cytolytics (enterotoxin -> food poisoning)
* Leukocidin (pus)
* Exotoxins (variable) |
|
|
Term
| Extracellular enzyme virulence factors of Staphylococcus |
|
Definition
* Coagulase
* Staphylokinase
* Lipase
* Beta-lactamase |
|
|
Term
| Antiphagocytic virulence factors of Staphylococcus |
|
Definition
* Polysaccharide slime layer
* Protein A |
|
|
Term
| Toxins produced by Staphylococcus |
|
Definition
* Cytolytics (enterotoxins causing food poisoning)
* Leukocidin (kill phagocytic WBCs, producing pus)
* Exotoxins (exfoliative toxin and TSS toxin) |
|
|
Term
| Are pathogenic Streptococci Gram-negative or Gram-positive? |
|
Definition
|
|
Term
| Major pathogenic species in genus Streptococcus |
|
Definition
* S. pyogenes
* S. pneumonia
* S. faecallis |
|
|
Term
| Other name for group A, beta-hemolytic Streptococcus |
|
Definition
|
|
Term
| Pathogenic species of Streptococcus that is alpha-hemolytic |
|
Definition
| S. pneumoniae, S. viridans |
|
|
Term
| Beta-hemolytic species of pathogenic Streptococcus |
|
Definition
|
|
Term
| Gamma-hemolytic pathogenic species of Streptococcus |
|
Definition
|
|
Term
| Lansfield group A Streptococcus is also called what? |
|
Definition
|
|
Term
| Colony morphology of Streptococci |
|
Definition
|
|
Term
| Diseases/disorders associated with Streptococcus pneumoniae |
|
Definition
* Bacteremia
* Pneumonia (85% of cases)
* Meningitis |
|
|
Term
| Species of Streptococcus commonly associated with endocarditis |
|
Definition
|
|
Term
| Are pathogenic Streptococci aerobic or anaerobic? |
|
Definition
|
|
Term
| Two ways of classifying Streptococci species |
|
Definition
* Immunogenic (Lansfield groups)
* Hemolysis (alpha, beta, gamma) |
|
|
Term
| Streptococcus pyogenes virulence factors |
|
Definition
* M protein (attachment, antiphagocytic, superantigen
* Hyaluronic acid capsule (antiphagocytic)
* Erythrogenic toxin (superantigen, scarlet fever rash)
* Exotoxin B (necrotizing fasciitis)
* Hemolysins/Streptolysins (blood-agar reaction)
* Streptokinase (fibrinolytic) |
|
|
Term
| S. pyogenes virulence factor that causes necrotizing fasciitis |
|
Definition
|
|
Term
| S. pyogenes virulence factor that causes strep throat |
|
Definition
|
|
Term
| Antiphagocytic virulence factors of S. pyogenes |
|
Definition
* M protein
* Hyaluronic acid capsule |
|
|
Term
| Superantigen virulence factors of S. pyogenes |
|
Definition
* M protein
* Erythrogenic toxin |
|
|
Term
| S. pyogenes virulence factor responsible for blood-agar reaction |
|
Definition
|
|
Term
| S. pyogenes virulence factor that causes scarlet fever rash |
|
Definition
|
|
Term
| S. pyogenes virulence factor that conveys tissue specificity and mediates attachment to host |
|
Definition
|
|
Term
| Antiphagocytic virulence factor of S. pyogenes that interferes with the C3b complement component |
|
Definition
|
|
Term
| Role of S. pyogenes erythrogenic toxin in disease |
|
Definition
|
|
Term
| Pathogenesis of rheumatic fever |
|
Definition
| S. pyogenes infection leads to Abs against M protein with cross-reactivity against myosin protein in heart, leading to heart valve damage |
|
|
Term
| Role of S. pyogenes in pathogenesis of acute glomerulonephritis |
|
Definition
| M protein antigen:antibody complexes lodge in glomeruli |
|
|
Term
| S. pyogenes disease associated with damaged mitral valve |
|
Definition
|
|
Term
| Substructure of S. pyogenes that is structurally similar to compounds in host's joints |
|
Definition
| Hyaluronic acid (in S. pyogenes capsule) |
|
|
Term
| Major pathogenic Neisseria species |
|
Definition
* N. meningitidis
* N. gonorrhoeae |
|
|
Term
| Neisseria species are Gram-negative or Gram-positive? |
|
Definition
|
|
Term
| Colony morphology of Neisseria |
|
Definition
|
|
Term
| Neisseria virulence factors |
|
Definition
* Polysaccharide capsule
* Fimbriae (attachment to mucosal epithelium)
* LPS
* Protease (cleaves IgA antibodies)
* Survival within macrophages |
|
|
Term
| Name for severe bacterial gastroenteritis |
|
Definition
|
|
Term
| How many E. coli O157:H7 cells does it take to cause disease? |
|
Definition
|
|
Term
| Bacteria associated with salmonellosis |
|
Definition
* S. enteritidis
* S. typhimurium |
|
|
Term
| Causative agent of travelers' diarrhea |
|
Definition
|
|
Term
| Colony morphology and Gram staining characteristics of E. coli |
|
Definition
|
|
Term
| Is E. coli part of the normal flora? |
|
Definition
|
|
Term
| E. coli virulence factors |
|
Definition
* Adhesins
* Fimbriae
* LPS
* Toxins |
|
|
Term
| Types of pathogenic E. coli |
|
Definition
* EHEC (enterohemorrhagic; eg, O157:H7; produces shiga-like toxin)
* ETEC (enterotoxigenic; two toxins; travelers' diarrhea)
* EPEC (enteropathogenic; shiga-like toxin; diarrhea in infants/children)
* EIEC (invasive colon disease; no toxins; invasiveness similar to Shigella)
* UPEC (uropathogenic; P-pili; most UTIs) |
|
|
Term
| Most enteric infections are Gram-negative or Gram-positive? |
|
Definition
|
|
Term
| Salmonella species that cause typhoid fever |
|
Definition
* S. typhi
* S. paratyphi |
|
|
Term
| Salmonella virulence factors |
|
Definition
* Fimbriae (attachment)
* Antigenic variation (change expression of H antigen)
* Pathogenicity islands (SPI-1, SPI-2) |
|
|
Term
| Name for collection of genes that encode a virulence factor or set of such factors in Salmonella species |
|
Definition
|
|
Term
| How do fimbriae convey virulence to Salmonella? |
|
Definition
| Allow for attachment to mucosal surface |
|
|
Term
| Bacteria associated with rapid mutation of H antigens |
|
Definition
|
|
Term
| Pathogenicity island that encodes proteins that prevent fusion of phagosome and lysosome |
|
Definition
|
|
Term
| Function of SPI-1 pathogenicity island in Salmonella |
|
Definition
| Allow for type III endocytosis of bacteria into host cell |
|
|
Term
| Is Helicobacter pylori Gram-negative or Gram-positive? |
|
Definition
|
|
Term
| H. pylori virulence factors |
|
Definition
* Flagella
* Adhesins
* Urease
* Toxins |
|
|
Term
| Function of urease on H. pylori |
|
Definition
| Catalyze conversion of urea and acid to bicarbonate and ammonium to allow H. pylori to inhabit acid environment of stomach |
|
|
Term
| Is urease a primary or secondary virulence factor? |
|
Definition
| Secondary, because it doesn't directly cause disease |
|
|
Term
| Pseudomonas aeruginosa colony morphology and Gram staining characteristics |
|
Definition
|
|
Term
| Major nosocomial pathogen of burn patients |
|
Definition
|
|
Term
| Pseudomonas aeruginosa virulence factors |
|
Definition
* Fimbriae
* Adhesins
* Capsule
* Pyocyanin (impairs cilia, triggers superoxide formation)
* Elastase
* Bacteriocins |
|
|
Term
| Major Gram-negative bacillus associated with cystic fibrosis |
|
Definition
|
|
Term
| P. aeruginosa virulence factor that leads to superoxide formation and cilia dysfunction |
|
Definition
|
|
Term
| Function of capsule in P. aerugionisa |
|
Definition
* Antiphagocytic
* Adhesion |
|
|
Term
| What is P. aeruginosa resistant to? |
|
Definition
| Wide range of antibiotics and disinfectants |
|
|
Term
| Conditions in which Pseudomonas aeruginosa is a significant threat |
|
Definition
* Burn victims
* Cystic fibrosis |
|
|
Term
| Colony morphology, metabolism, and staining of Bacteroides fragilis ("B. frag") |
|
Definition
| Gram-negative anaerobic bacillus |
|
|
Term
| Predominant microbe of colon |
|
Definition
|
|
Term
| Bacteroides fragilis virulence factors |
|
Definition
* LPS
* Capsule
* Protease
* Enterotoxin
* Beta-lactamase |
|
|
Term
| Pathogen that can cause septicemia and peritoneal abscesses |
|
Definition
|
|
Term
| Two main pathogens that produce endospores |
|
Definition
|
|
Term
| Bacteria responsible for gangrene |
|
Definition
|
|
Term
| Causative agent of pseudomembranous colitis and severe diarrhea |
|
Definition
|
|
Term
| Clostridium virulence factors |
|
Definition
* Endospores
* Exotoxins
* Collagenase
* Hyaluronidase
* Protease |
|
|
Term
| Etiologic agent of botulism |
|
Definition
|
|
Term
| Causative agent of tetanus disease |
|
Definition
|
|
Term
| Disease associated with Clostridium perfringens |
|
Definition
|
|
Term
| Disease associated with Clostridium difficile |
|
Definition
|
|
Term
| Botulinum toxin mechanism of action |
|
Definition
| Blocks release of acetylcholine from neuromuscular junction by inhibiting exocytosis machinery (VASP, SNAPs), causing flaccid paralysis |
|
|
Term
| Tetanus toxin mechanism of action |
|
Definition
| Inhibits release of inhibitory neurotransmitters through similar mechanism as botulinum toxin, causing ridig paralysis (lockjaw) and respiratory failure (spastic paralysis) with high mortality |
|
|
Term
| Bacteria that stains with acid-fast |
|
Definition
|
|
Term
| Mycobacterium staining characteristics |
|
Definition
* Gram-positive
* Acid-fast |
|
|
Term
| Bacteria capable of surviving within host macrophages |
|
Definition
* Neisseria
* Mycobacteria
* Salmonella
* Listeria |
|
|
Term
| Causative agent of leprosy (Hansen's disease) |
|
Definition
|
|
Term
| Etiologic agent of tuberculosis |
|
Definition
| Mycobacterium tuberculosis |
|
|
Term
| Mycobacteria virulence factors |
|
Definition
* Mycolic acid
* Survives in alveolar macrophages
* Cord factor |
|
|
Term
| Function of Mycobacterial cord factor |
|
Definition
| Cell wall protein keeps daughter cells attached after division; required for pathogenesis |
|
|
Term
| Virulence factor of Mycobacterium that allows it to remain viable in aerosol drops |
|
Definition
| Mycolic acid in cell wall |
|
|
Term
|
Definition
|
|
Term
| Example of a Gram-positive acid-fast pathogen |
|
Definition
|
|
