Cumulative MM flashcard set

from copilot, yeah I'm ashamed

DFI screen

Identifies promoters induced in vivo; requires suicide plasmid for chromosomal integration.

STM screen

Missing tags in recovered pool indicate attenuated mutants required for virulence.

Invasion assay

Gentamicin protection assay distinguishes attachment vs invasion.

Complementation test

Adding gene back restores phenotype and proves causation.

Cytotoxicity assay

Measures host cell lysis via LDH release.

TLR4

Detects LPS.

TLR5

Detects flagellin.

TLR9

Detects CpG DNA.

NOD1/NOD2

Detect peptidoglycan fragments.

NK cell KIR

Recognizes MHC I and inhibits killing.

NK cell NKG2D

Recognizes stress ligands and activates killing.

Inflammasome

Activates caspase‑1 to release IL‑1β and IL‑18.

MHC I

Activates CD8+ T cells for intracellular pathogens.

MHC II

Activates CD4+ T cells for extracellular pathogens.

Superantigen

Binds outside MHC–TCR groove causing massive T‑cell activation.

IFN‑γ release assay

Measures Th1 memory response to TB antigens.

BvgAS system

Bvg+ activates virulence genes; Bvg– activates motility genes.

Pertussis toxin

ADP‑ribosylates Gi to increase cAMP.

CFTR mutation

Causes thick mucus and promotes Pseudomonas biofilms.

AHL quorum sensing

Activates biofilm and toxin genes at high density.

Pyocyanin

Oxidizes NADPH/NADH and generates ROS.

CR1/CR3/CR4

Entry receptors enabling “silent entry.”

LAM

Blocks vesicle trafficking and phagosome maturation.

PtpA

Blocks lysosome docking by dephosphorylation.

PtpB

Prevents apoptosis and inflammation.

Siderophores

Acquire iron for intracellular survival.

ESX‑1 secretion

Required for virulence and cytosolic access.

RIG‑I/MDA5

Detect viral dsRNA.

Double‑membrane vesicles

Hide viral RNA from innate sensors.

dsDNA virus replication

Uses host polymerases; low mutation rate.

ssRNA(+) virus replication

Uses viral RdRp; high mutation rate.

M protein

Prevents C3b opsonization; molecular mimicry causes rheumatic fever.

SpeA/B/C

Superantigens causing toxic shock.

S. pyogenes hemolysis

Beta‑hemolytic and bacitracin sensitive.

S. pneumoniae virulence

Capsule is primary virulence factor.

Dot/Icm system

Legionella Type IVB secretion blocking lysosome fusion.

Legionella replicative form

Non‑motile, intracellular growth.

Legionella transmissive form

Flagellated and infective.

Coxiella niche

Acidic phagolysosome where it thrives.

Coxiella secretion

Type IV secretion but does not block fusion.

SPI‑1 function

Mediates invasion of epithelial cells.

SPI‑2 function

Maintains SCV and intracellular survival.

SopE/SopE2

GEF mimics activating Cdc42/Rac.

SipA

Stabilizes actin filaments.

SipC

Nucleates and bundles actin.

SptP

GAP that reverses cytoskeletal rearrangements.

SopB

PI phosphatase causing ruffling, Cl‑ secretion, caspase‑1 activation.

SifA/PipB2

Form SIFs for SCV maintenance.

SseF/SseG

Anchor SCV near Golgi.

GtgE

Cleaves Rab32 to allow survival in mouse macrophages.

Rab32

Restricts S. Typhi in mice.

CdtB

DNase component of typhoid toxin.

PtlA

ADP‑ribosyltransferase of typhoid toxin.

PtlB

Binding subunit of typhoid toxin.

Typhoid toxin export

SCV

EPEC

LEE T3SS forms pedestals; no shiga toxin.

EHEC

Produces shiga toxin; no invasion.

ETEC

LT/ST toxins cause watery diarrhea.

EIEC

Shigella‑like invasion and intracellular spread.

Infectious dose

10–500 organisms.

Invasion plasmid

Encodes Mxi‑Spa T3SS.

IpaB

Activates caspase‑1 to kill macrophages.

IcsA

Actin‑based motility.

VirF

Temperature‑regulated master activator at 37°C.

VirB

Activates T3SS genes downstream of VirF.

Cytoplasmic replication

After vacuole escape.

Internalin A

Binds E‑cadherin for invasion.

LLO (Listeriolysin O)

Vacuole escape.

ActA

Mimics WASP to drive actin rockets.

Perforin A

Membrane disruption.

Motility

Cell‑to‑cell spread via actin.

Yops

Block phagocytosis.

YopE

GAP targeting Rho GTPases.

YopH

Tyrosine phosphatase blocking signaling.

YopJ

Blocks MAPK and NF‑κB.

YadA

Adhesion to host cells.

YMT

Required for flea survival.

T3SS

Central virulence mechanism.

Cholera toxin acquisition

Via CTXφ bacteriophage.

Serogroups O1/O139

Cause epidemic cholera.

T6SS

Kills competing bacteria.

Polar flagellum

Motility.

Two chromosomes

Vibrio genome structure.