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.