ENZYMES, GROWTH FACTORS, PROTEINS, AND RECEPTORS

DNA polymerase

What enzyme is inhibited by Brincidofovir (CMX001 or Tembexa) for the treatment of human smallpox disease?

orthopoxvirus protein

What protein, required for the formation of an infectious virus particle, is potently inhibited by Tecovirimat (TPOXX)?

IL-1

What endogenous pyrogen is elicited by pathogens and helps increase the hypothalamic set point for fever?

IL-6

What endogenous pyrogen is elicited by pathogens and is released by dendritic cells upon beta-1,3-glucan engagement?

Tumor necrosis factor

What endogenous pyrogen is released in large amounts by polyclonal T-cell proliferation caused by superantigens, and helps increase the hypothalamic set point for fever?

Ciliary neurotrophic factor (CNTF)

What is one example of an endogenous pyrogen that elicits fever?

Interferon-alpha (IFN-alpha)

What endogenous pyrogen is elicited by pathogens, leading to fever?

neuropeptides

What substance is speculated to function as a central antipyretic, mediating the natural thermal ceiling of fever in the pre-antibiotic era?

norepinephrine

What substance is released by the hypothalamus to preserve and produce heat by increasing heat production in brown adipose tissue and inducing vasoconstriction?

Acetylcholine

What substance stimulates the muscles to shiver, converting stored chemical energy into heat?

Prostaglandin E2 (PGE2)

What major fever inducer is synthesized in the hypothalamus and acts on thermoregulatory neurons to raise the body’s temperature set-point?

Superantigens

What virulence factors of S. aureus cause polyclonal T-cell proliferation and release large amounts of IL-1 and TNF?

Antibiotic resistance proteins

What type of virulence factor is produced by S. aureus to survive and infect host structures?

Receptors for fibrinogen (clumping factor)

What receptor used by S. aureus helps the bacteria adhere to the endothelium and facilitate infection?

Receptors for fibronectin

What receptor helps S. aureus adhere to the endothelium and facilitate infection?

Receptors for vitronectin

What receptor helps S. aureus adhere to the endothelium and facilitate infection?

alpha-toxin

What S. aureus toxin forms membrane pores allowing calcium to enter the cell, which causes cell death and damage?

beta-toxin

What S. aureus toxin is a Sphingomyelinase that helps degrade parts of the cell?

delta-toxin

What S. aureus toxin is a detergent-like peptide that causes damage to cells?

gamma-toxin

What S. aureus toxin functions to lyse red cells?

Leukocidin

What S. aureus toxin functions to lyse WBCs or phagocytes?

Exfoliative A and B Toxins

What S. aureus toxins are serine proteases that cleave desmoglein 1?

Serine proteases

What type of enzyme is responsible for cleaving desmoglein 1, causing keratinocyte detachment in Scalded Skin Syndrome?

desmoglein 1

What molecule is cleaved by S. aureus Exfoliative A and B Toxins, leading to skin exfoliation?

enterotoxins (S. aureus)

What superantigens produced by S. aureus cause various gastrointestinal symptoms in food poisoning?

Antistreptococcal M protein antibodies and T cells

What proteins cross-react with cardiac proteins, causing the cardiac manifestations of rheumatic fever?

M protein (S. pyogenes)

What anti-phagocytic virulence factor is produced by S. pyogenes?

Complement C5a peptidase

What S. pyogenes virulence factor interferes with the innate immune system complement system?

Phage-encoded pyrogenic exotoxin

What virulence factor of S. pyogenes causes scarlet fever?

Pneumolysin

What virulence factor of S. pyogenes lyses cells by disrupting the cell membrane?

high-molecular weight glucans

What substance is secreted by S. mutans leading to bacterial aggregation and plaque formation?

Antiphagocytic capsule (Enterococci)

What virulence factor contributes to the low virulence of Enterococci and helps avoid destruction?

enzymes (Enterococci)

What molecules produced by Enterococci function to injure host tissues?

Phage-encoded A-B toxin (Diphtheria)

What toxin blocks host cell protein synthesis by inhibiting Elongation Factor-2?

Elongation Factor-2

What protein synthesis factor is inhibited by Diphtheria's Phage-encoded A-B toxin?

Listeriolysin O

What pore-forming protein helps Listeria monocytogenes escape the phagolysosome?

Act A

What Listeria surface protein induces actin polymerization to propel the bacteria into adjacent uninfected cells, dubbed as “actin rockets”?

Antiphagocytic polyglutamyl capsule (Anthrax)

What protein structure helps Bacillus anthracis avoid the human immune system?

protective antigen (B subunit of Anthrax toxin)

What Anthrax toxin subunit binds the endothelial receptor, allowing delivery of the A subunit into the host cell?

Edema Factor (EF) (A subunit of Anthrax toxin)

What Anthrax toxin subunit binds calcium and calmodulin to form an adenylate cyclase?

calmodulin

What molecule does Edema Factor (EF) bind along with calcium?

adenylate cyclase (Anthrax toxin related)

What enzyme is formed when Edema Factor (EF) binds calcium and calmodulin, converting ATP to cAMP and altering cell function?

Lethal Factor (LF) (A subunit of Anthrax toxin)

What Anthrax toxin subunit is a protease that destroys mitogen-activated protein kinase kinases?

mitogen-activated protein kinase kinases

What host proteins are destroyed by the Lethal Factor (LF) of the Anthrax toxin?

Capsule (N. meningitidis)

What structure inhibits opsonization, helping N. meningitidis avoid the immune system?

CD46

What epithelial cell receptor is bound by the long pili of N. gonorrhoeae during adherence?

OPA proteins

What outer membrane proteins in N. gonorrhoeae increase binding to epithelial cells and promote bacterial entry into host cells?

pili proteins (N. gonorrhoeae)

Recombination of the genes coding for these proteins allows N. gonorrhoeae to use antigenic variation to escape the immune response?

filamentous hemagglutinin

What Bordetella pertussis factor binds carbohydrates on respiratory epithelial cells and CR3 (Mac-1) integrins on macrophages?

CR3 (Mac-1) integrins

What receptors on macrophages are bound by the filamentous hemagglutinin of B. pertussis?

Pertussis Toxin (A-B Toxin) A unit

What unit of Pertussis Toxin ADP-ribosylates and inactivates guanine nucleotide-binding proteins?

Pertussis Toxin (A-B Toxin) B unit

What unit of Pertussis Toxin has 4 subunits which allows the A unit to enter the cell?

guanine nucleotide-binding proteins (G proteins)

What proteins are inactivated by the A unit of Pertussis Toxin via ADP-ribosylation?

Toxic Adenylate Cyclase

What Bordetella pertussis factor converts ATP to cAMP, which inhibits phagocytosis and oxidative burst in neutrophils and causes apoptosis of macrophages?

A-B Exotoxin (P. aeruginosa)

What virulence factor inhibits host protein synthesis via ADP ribosylation of Elongation Factor-2?

Elastase (P. aeruginosa)

What exoenzyme produced by P. aeruginosa degrades the extracellular matrix?

Leukocidin (P. aeruginosa)

What virulence factor produced by P. aeruginosa kills leukocytes?

Hemolysin (P. aeruginosa)

What virulence factor produced by P. aeruginosa destroys cell membranes?

Alginate (P. aeruginosa)

What mucoid exopolysaccharide forms a biofilm, protecting the bacteria from immune components and antibiotics?

Yop virulon

What plasmid-borne complex of genes in Yersinia pestis injects bacterial proteins (Yops) into the host cell?

Yops (YopE, YopH, YopT)

What bacterial proteins, injected by Yop virulon, block phagocytosis by inactivating actin polymerization?

YopJ

What bacterial protein, injected by Yop virulon, inhibits pathways activated by LPS, preventing inflammatory cytokines?

mycolic acids

What specific glycolipids and lipids are responsible for the waxy cell wall structure of mycobacteria?

mannose-binding lectin

What macrophage receptor is used by M. tuberculosis to enter the macrophage via phagocytosis?

CR3 (macrophage receptor)

What macrophage receptor is used by M. tuberculosis to enter the macrophage via phagocytosis?

IL-12

What cytokine drives the TH1 response against TB and is released from dendritic cells upon TLR2 stimulation?

toll-like receptor 2 (TLR2)

What receptor is stimulated by mycobacterial ligands to promote IL-12 production by antigen-presenting cells?

Interferon-gamma (IFN-gamma)

What cytokine, primarily from TH1 cells, stimulates the maturation of the phagolysosome and the expression of inducible nitric oxide synthase (NOS)?

inducible nitric oxide synthase (NOS)

What enzyme's expression is stimulated by Interferon-gamma (IFN-gamma) to aid in bacterial killing?

antimicrobial peptides (defensins)

What molecules' mobilization is stimulated by Interferon-gamma (IFN-gamma) against bacteria?

Interferon-gamma (IFN-gamma)

What function does this cytokine perform by stimulating autophagy in infected macrophages?

Interferon-gamma (IFN-gamma)

What function does this cytokine perform to mobilize antimicrobial peptides (defensins) against bacteria?

Interferon-gamma (IFN-gamma)

What function does this cytokine perform by stimulating the maturation of the phagolysosome in infected macrophages?

Interferon-gamma (IFN-gamma)

What function does this cytokine perform by stimulating the expression of inducible nitric oxide synthase (NOS)?

IL-12 receptor

Genetic deficiencies in what receptor pathway increase susceptibility to Tuberculosis?

Interferon-gamma receptor

Genetic deficiencies in what receptor pathway increase susceptibility to Tuberculosis?

TprK protein gene

What gene in T. pallidum undergoes recombination to cause antigenic diversity and escape the immune response?

cardiolipin

What host tissue antigen do nontreponemal syphilis tests (RPR, VDRL) test for specific antibodies against?

lipoproteins (bacterial)

What molecules in Borrelia burgdorferi bind to TLR2 on macrophages, initiating immune damage in Lyme disease?

IL-6 (Lyme disease related)

What cytokine is released upon the binding of bacterial lipoproteins to TLR2 in Lyme disease pathogenesis?

Tumor necrosis factor (TNF) (Lyme disease related)

What cytokine is released in Lyme disease that helps generate bactericidal reactive nitrogen intermediates?

antigenic surface protein (Borrelia burgdorferi)

Variation in the gene coding for this protein allows B. burgdorferi to escape neutralizing antibodies?

collagenase (Clostridium)

What enzyme produced by Clostridium degrades extracellular matrix proteins, facilitating invasion and destruction?

hyaluronidase (Clostridium)

What enzyme produced by Clostridium degrades extracellular matrix proteins, facilitating invasion and destruction?

collagenase and hyaluronidase

What two enzymes produced by Clostridium degrade extracellular matrix proteins, allowing invasion and destruction?

alpha-toxin (Clostridium perfringens)

What phospholipase C degrades cell membranes and has sphingomyelinase activity that can cause nerve sheath damage?

phospholipase C (C. perfringens)

What type of enzyme is the alpha-toxin, responsible for degrading cell membranes?

Enterotoxin (Clostridium perfringens)

What toxin forms pores in epithelial cell membranes, leading to damage and diarrhea in food poisoning?

toxins (C. tetani)

What prevents the release of gamma-aminobutyric acid (GABA), causing spastic paralysis (tetanus)?

gamma-aminobutyric acid (GABA)

What inhibitory neurotransmitter's release is blocked by C. tetani toxins?

Neurotoxin (C. botulinum)

What toxin binds gangliosides on motor neurons and cleaves synaptobrevin, blocking acetylcholine release?

gangliosides

What molecules on motor neurons are bound by the C. botulinum neurotoxin?

synaptobrevin

What molecule is cleaved by a fragment of C. botulinum neurotoxin, blocking neurotransmitter vesicle fusion?

acetylcholine

What neurotransmitter's synaptic release is prevented by C. botulinum neurotoxin, resulting in flaccid paralysis?

Toxin A (C. difficile)

What enterotoxin stimulates chemokine production, recruiting white blood cells in pseudomembranous colitis?

Toxin B (C. difficile)

What cytotoxin has direct cytopathic effects in pseudomembranous colitis?

Membrane pumps (Chlamydia)

What structures allow Chlamydia to capture amino acids and ATP for survival inside host cells?

Elementary body (C. trachomatis)

What is the infectious, metabolically inactive form of C. trachomatis that prevents phagolysosome fusion?

Reticulate body (C. trachomatis)

What is the metabolically active form of C. trachomatis that uses host cell ATP and amino acids to replicate?

Reticulate body (C. trachomatis)

What metabolically active form of C. trachomatis uses ATP and amino acids from the host cell to replicate?