Search on : Yeasts 2011

 


    

Taxonomy

 Link to MycoBank:
 
 Link to previous version of yeast database:
 
 Associated species:
 
 Authors:Pitt & M.W.
Miller
 
 Year:1968 
 Ecology:Metschnikowia reukaufii appears to be cosmopolitan in distribution,
unlike many other species associated with flowers or
insects that feed or breed in flowers, which would support an association
with the common bumblebee Bombus terrestris, which has also
become more or less ubiquitous in range.
 
 
Strains
 Type strain:
 
 Other strains:
 
 Gene sequence accession numbers, type strain:D1/D2 LSU rRNA 5
U44825.
 
 Origin of the strains studied:CBS 5834 (UCD-FST 62-311) diploid, isolated
by J.F.T. Spencer from flower of fireweed (Epilobium angustifolium,
Onagraceae), Fort Smith, NWT, Canada. The strains studied by Miller and
Phaff (1998) were obtained from flowers over a wide geographic area:
near Fort Smith, North West Territory, Canada (17); Saskatoon,
Saskatchewan, Canada (5); Davis, California, USA (1); Japan (1); State of
Washington, USA (1). More recent isolates whose identity has been confirmed
by sequencing include SUB 99-213.2, flower of morning glory
(Ipomoea sp., Convolvulaceae), and SUB 99-221.2, flower of larger bindweed
(Calystegia sepium, Convolvulaceae), Smoky Mountains National
Park, Tennessee, USA; UWOPS 03-342o2, from milkweed beetle
Tetraopes tetraophthalmus (Coleoptera: Cerambycidae), collected in a
flower of Calystegia sepium, Long Point, Ontario, Canada; UWOPS 06-29.1
and UWOPS 06-32.1, Azalea sp. flower, Statesboro, Georgia, USA;MH396,
proboscis of bumble bee (Bombus sp., Hymenoptera, Apidae); MH 412
and MH 421, nectar of stinking hellebore (Helleborus foetidus,
Ranunculaceae),Marburg, Germany.
 
 Type strain:CBS 5834 
 
Classification
 Division:Ascomycota 
 Subdivision:Saccharomycotina 
 Class:Saccharomycetes 
 Subclass:Saccharomycetidae 
 Order:Saccharomycetales 
 Family:Metschnikowiaceae 
 Genus:
 
 Synonyms:Candida reukaufii (Grüss) Diddens & Lodder (1942)
Chlamydozyma reukaufii Wickerham (1964a)
Chlamydozyma zygota Wickerham (1964a)
Metschnikowia zygota Fell & I.L. Hunter (1968)1
 
 Basis for synonymy:1 Synonymy based on fertility of hybrids 
 Anamorph:Candida reukaufii (Grüss) Diddens & Lodder 
 Systematics:Many strains previously reported as M. reukaukii may in
fact be cryptic representatives of other species. The physiological profile
of the species varies from strain to strain and a clear distinction
from many relatives is often not possible. One such example is Candida
rancensis, reported as a synonym by Miller and Phaff (1998a). The latter
is now recognized as valid based on D1/D2 LSU rRNA gene sequences,
which are quite distinct. Isolates found in nectar of milkweeds and
identified as M. reukaukii (Eisikowitch et el. 1990) were later described
as M. lachancei or M. vanudenii (Giménez-Jurado et al. 2003), and others
from morning glory flowers, originally designated as M. reukaufii-like
on the basis of growth responses (Lachance et al. 1988b), were later
described as Candida ipomoae (Lachance et al. 1998a).
 

Morphology

 Growth on YM/malt agar:After 1 month at 25C, growth is cream
colored, the surface is smooth and glistening, in some strains
sparsely papillate, and the edge is entire to crenulate.
 
 Growth in YM broth/(5%) malt extract:After 3 days at 25C, the cells are ellipsoid
to cylindroid, 26 3 418 ìm, usually 24 3 612 ìm, and
occur singly or catenulate, reproducing by multilateral budding. In
some strains longer cells occur, up to 35 ìm. Chlamydospores are not
present. After 1 month at 25C, somewhat elongate chlamydospores
are usually present, 410 3 830 ìm, but usually 810 3
1020 ìm. They are highly refractile, and contain several to numerous
lipid globules; a thin ring is present, a pellicle is absent.
 
 Dalmau plate cultures on potato and corn meal agar media:Aerobically, pseudohyphae
are not produced; anaerobically, rudimentary pseudohyphae
are profusely formed.
 

Sexuality

 Formation of ascospores:Asci arise from somewhat elongated chlamydospores
that contain several to numerous lipid globules. Asci are
ellipsoidopedunculate to clavate, 59 3 2043 μm, usually 58 3
3037 μm, containing two (rarely one) acicular to acerose ascospores,
0.71.1 3 730 μm (Fig. 46.28). Asci do not lyse at maturity.
Asci develop on dilute (1:2 to 1:29), filtered V8 juice agar, and other
dilute media after 721 days at 1221C (Pitt and Miller 1968).
 

Physiology

 
Fermentations
 D-Glucose (F1):+ 
 D-Galactose (F2):-, + 
 Maltose (F3):- 
 Sucrose (F5):- 
 a,a-Trehalose (F6):- 
 Lactose (F8):- 
 Raffinose (F11):- 
 
Assimilations & growth tests
 
Temperatures growths tests :
at 4ºC ?
at 12ºC ?
at 15ºC ?
at 19ºC yes
at 21ºC ?
at 25ºC yes
 
at 30ºC yes
at 35ºC ?
at 37ºC variable
at 40ºC ?
at 42ºC ?
at 45ºC ?
 
 
Assimilations:
Glucose +
Inulin -
Sucrose +
Raffinose -
Melibiose -
Galactose -, +
Lactose -
Trehalose -, +
Maltose +
Melezitose +
Methyl-α-D-glucoside -, +
Soluble starch -
Cellobiose +
Salicin +
L-Sorbose +
L-Rhamnose -
D-Xylose -, +
L-Arabinose -
D-Arabinose -, +
D-Ribose -, +
Methanol -
Ethanol -, +
Glycerol +
Erythritol -
Ribitol -, +
Galactitol -
D-Mannitol +
D-Glucitol +
myo-Inositol -
 
DL-Lactate -
Succinate +
Citrate -, +
D-Gluconate +
D-Glucosamine -, +
N-Acetyl-D-glucosamine +
Hexadecane +
Nitrate -
Nitrite -
Vitamin-free -
2-Keto-D-gluconate +
5-Keto-D-gluconate ?
Saccharate ?
Xylitol +
L-Arabinitol ?
Arbutin ?
Propane 1,2 diol ?
Butane 2,3 diol ?
Cadaverine +
Creatinine ?
L-Lysine +
Ethylamine +
50% Glucose -, +
10% NaCl/5% glucose ?
Starch formation -
Urease ?
Gelatin liquefaction -, +
Cycloheximide 0.01% -
Cycloheximide 0.1% -
 
 Diazonium Blue B reaction (M4):- 
 Coenzyme Q system:9 
 Cell carbohydrates:Glucose and mannose are present in the cell
wall (Lopandic et al. 1996).
 

DNA

 Molecular % G+C (Average):41.3 
 Type sequences:LSU-U44825