Ureaplasma

Abstract

U.re.a.plas'ma. N.L. fem. n. urea urea; Gr. neut. n. plasma anything formed or moulded, image, figure; N.L. neut. n. Ureaplasma urea form. Tenericutes / Mollicutes / Mycoplasmatales / Mycoplasmataceae / Ureaplasma Coccoid cells about 500 nm in diameter ; may appear as coccobacillary forms in exponential growth phase; filaments are rare. Nonmotile. Facultative anaerobes. Form exceptionally small colonies on solid media that are described either as tiny ( T ) “ fried‐egg ” colonies or as “ cauliflower head ” colonies having a lobed periphery. Unusual pH required for growth ( about 6 . 0–6 . 5 ). Optimal incubation temperature for examined species is 35–37°C. Chemo‐organotrophic. Like Mycoplasma , species of Ureaplasma lack oxygen‐dependent, NADH oxidase activity . Unlike Mycoplasma , species of Ureaplasma lack hexokinase or arginine deiminase activities but have a unique and obligate requirement for urea and produce potent ureases that hydrolyze urea to CO 2 and NH 3 for energy generation and growth. Genome sizes range from 760 to 1170 kbp (PFGE). Commensals or opportunistic pathogens in vertebrate hosts, primarily birds and mammals (mainly primates, ungulates, and carnivores). DNA G + C content ( mol %): 25–32 (Bd, T m ). Type species : Ureaplasma urealyticum Shepard, Lunceford, Ford, Purcell, Taylor‐Robinson, Razin and Black 1974, 167 emend. Robertson, Stemke, Davis, Harasawa, Thirkell, Kong, Shepard and Ford 2002, 593.