Spirillum

A genus of large (1.4–1.7 μm in diameter), rigid, helical, Gram-negative bacteria (family Spirillaceae) that are motile by means of bipolar fascicles of flagella. These freshwater organisms are obligately microaerophilic and chemoorganotrophic, possessing a strictly respiratory metabolism; they neither oxidize nor ferment carbohydrates. The type species is S. volutans. [Mod. L. dim. of L. spira, coil, fr. G. speira]

- S. minus a species of uncertain taxonomic classification that causes a form of rat-bite fever (sodoku). This species has never been cultured.

- S. volutans a species found in fresh water; it is the type species of S..

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spi·ril·lum spī-'ril-əm n

1) cap a genus of gram-negative bacteria comprising elongated forms having tufts of flagella at both poles and usu. living in stagnant water rich in organic matter see RAT-BITE FEVER (b)

2) pl -ril·la -'ril-ə any bacterium of the genus Spirillum

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n.

a genus of highly motile rigid spiral-shaped bacteria usually found in fresh and salt water containing organic matter. They bear tufts of flagella at one or both ends of the cell. Most species are saprophytes, but S. minus causes rat-bite fever.

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Spi·ril·lum (spi-rilґəm) [L., dim. of spira coil] a genus of gram-negative bacteria of the family Spirillaceae, consisting of short, rigid, helical cells with bipolar flagella; organisms are motile, and microaerophilic or aerobic, with a respiratory metabolism, and are found in stagnant freshwater environments. The type species is S. voґlutans.