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By the name of Allah. Report about: Bacterial Motility by : Islam Radi 220050911 Supervised by Dr. Abdelraouf A. Elmanama. introductio n. Most bacteria, but not all, that are motile, move by using structures call FLAGELLA
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By the name of Allah Report about: Bacterial Motility by : Islam Radi 220050911 Supervised by Dr. Abdelraouf A. Elmanama
introduction Most bacteria, but not all, that are motile, move by using structures callFLAGELLA Flagella are long rigid rod-like structures made of repeating protein subunits They are attached to a MOTOR located in the cell wall that turns them like a propeller. The flagella motor is powered by a flow of PROTONS, sort acting like electricity
As flagella rotate they turn or rotate like a propeller and drive the bacterial cell through liquid • We will use this ability to detect whether the test bacteria are motile or non-motile
The following flagellar arrangements may be found Monotrichous: a single flagellum at one pole
Lophotrichous: two or more flagella at one or both poles of the cell
MOTILITY AGAR **Motile bacteria require liquid to move. Thus bacteria can propel themselves in broth or across the surface of a wet agar plate. **They will not however move whenembedded in 1.5% agar,the minimum concentration found in most agar media. **Semisolid agar has a reduced agar concentration (0.4 %) that allows flagellated bacteria to migrate from the site of inoculation..
**Semisolid media are prepared in tubes and are inoculated through most of their length by stabbing with a needle. **Thus after 48 hours of incubation, growth of a motile organism will be observed as a turbid region extending from the stab. **Nonmotile bacteria will only grow along the stab line
**inoculate the tube by stabbing with the needle to approximately three-quarters of its depth Be careful to bring the needle into the center of the medium and not to touch the side of the tube • Incubate at room temperature for 48 hours • **Examine for growth
HANGING DROP SLIDE **This method is commonly used to view living organisms for the rapid determination of motility. **The hanging drop is prepared by suspending a fluid sample from a coverslip over a depression well in a specially designed microscope slide.
MATERIALS *Depression slides Cover slips** ***Petroleum jelly ****Toothpicks
Procedure *With the toothpick , put a small amount of petroleum on each corner of the cover slip ** place one or tow loopful of a culture in the center of cover slip *** the depression slide is placed on the cover slip with the depression over the frop of fluid **** Examine with low power