Mycoplasma mobile sp. nov., a New Species from Fish

Abstract

Mycoplasma strain 163K was isolated from the gills of a tench (Tinca tinca L.) with red disease. The cells are elongated, ovoid or flask shaped, consisting of a thicker body and a more slender part ending in a hemispherical terminal structure, that is apparently stabilized by a cytoskeleton. They are able to attach to inert surfaces and living cells. The most exciting property of the organisms is their fast gliding motion, which occurs on glass and plastic surfaces and which is not interrupted by resting periods. Growth occurs between 17 and 30.degree. C, with an optimum at 25.degree. C, in modified Hayflick medium with horse or bovine serum and in medium with swine serum. Acid is produced from several carbohydrates, but arginine and urea are not catabolized. The organism reduces tetrazolium chloride, produces film and spots and hydrogen peroxide, and is able to hemolyze and to adsorb to erythrocytes of several animal species. Indirect immunofluorescence test, growth inhibition, and metabolism inhibition tests indicate that the mycoplasma represents a new species for which the name Mycoplasma mobile is proposed. Strain 163K (ATCC 43663) is the type strain.