Lab method
Motility test concept
Diffuse growth from the stab = motile
High-yield clue
Cloudy spreading away from the stab line indicates a motile, flagellated organism such as Proteus.
Overview
A semisolid-medium concept where organisms with flagella spread out from the inoculation stab, producing diffuse cloudiness rather than growth confined to the stab line.
Classification
- Semisolid motility medium concept
- Detects flagellar motility
- Often paired with indole (SIM)
Lab & identification clues
- Diffuse haze from stab = motile
- Growth only along stab = non-motile
- SIM medium combines sulfide, indole, motility
- Tetrazolium/TTC can highlight growth
Associations
- Proteus swarming study vocabulary
- Klebsiella is a non-motile contrast
- Flagella and identification framing
Commonly confused with
- TSI agar
- Triple sugar iron agar
Your notes
Original concept summary for coursework. Sources checked: OpenStax Microbiology 2e and NCBI Bookshelf Medical Microbiology; reviewed 2026-06. Describes vocabulary and interpretation concepts only; not a lab protocol and not for handling specimens or identifying patient isolates.