Quorum Sensing and Bioluminescence in Bacteria

Bioluminescence

Light production by living organisms.

Quorum

Minimum entities required for a process.

Vibrio harveyi

Bioluminescent bacteria using quorum sensing.

Hawaiian Bobtail Squid

Host organism for Vibrio harveyi.

Signal Reception

Initial detection of signaling molecules.

Transduction

Conversion of a signal into a cellular response.

Response

Cellular action following signal transduction.

Signal Molecules

Chemical messengers for communication between cells.

AI-1

Autoinducer molecule for quorum sensing.

AI-2

Another autoinducer molecule for signaling.

Receptors

Proteins that bind signal molecules.

Phosphorylation

Addition of phosphate group to proteins.

Signaling Cascade

Series of biochemical events triggered by a signal.

Activated Transcription Factor

Protein that initiates gene transcription.

LuxO

Regulatory protein in quorum sensing pathway.

Luciferase

Enzyme that catalyzes bioluminescence.

Luciferase Gene

Gene encoding the luciferase enzyme.

Luciferin

Substance that produces light when oxidized.

Colony Forming Units (CFUs)

Estimate of viable bacterial cells.

Serial Dilution

Stepwise dilution to reduce concentration.

Aseptic Technique

Methods to prevent contamination in experiments.

Incubation

Process of maintaining conditions for growth.

Aliquot

A portion of a larger sample.

Dilution Factor

Ratio used to calculate concentration changes.

Cell Contact Mediated

Direct signaling through cell-to-cell contact.

Secreted and Diffusible

Signals that spread through the environment.

Light Production

Result of luciferase activity in bacteria.

Nutrient Agar Plates

Growth medium for culturing bacteria.

Colony Counting

Method to estimate bacterial concentration.