Swarming growth is shown by which gram positive bacilli: September 2009
Ans. A: Clostridium tetani C tetani is an anaerobic gram-positive rod that forms terminal spores, giving it a characteristic tennis racquet appearance. Some strains do not sporulate readily, and spores may not appear until the third or fouh day of culture. Most strains are motile with peritrichous flagella; colonies often swarm on agar plates, but some strains are nonflagellated and nonmotile. The presence of C tetani should be suspected on isolation of a swarming rod that produces indole and has terminal spherical spores, but does not produce acid from glucose. Toxigenic C tetani contains a plasmid that produces a toxin called tetanospasmin, but nontoxigenic strains also exist. Tetanospasmin is responsible for the infamous toxemia called tetanus. The two animal species most susceptible to this toxemia are horses and humans.
Clostridium tetani
Clostridium welchii
Proteus
All of the above