Psychrophilic yeasts in glacial environments of Alpine glaciers.
The presence of psychrophilic yeasts in supra- and subglacial sediments, ice and meltwater collected from two glaciers of the Italian Alps (Forni and Sforzellina-Ortles-Cevedale group) was investigated. After incubation at 4 degrees C, subglacial sediments contained from 1.3 x 10(3) to 9.6 x 10(3) CFU of yeasts g(-1). The number of yeast cells in supraglacial sediments was c. 10-100-fold lower. A significant proportion of isolated yeasts exhibited one or more extracellular enzymatic activities (starch-degrading, lipolytic, esterolytic, proteolytic and pectinolytic activity) at 4 degrees C. Selected isolates were able to grow at 2 degrees C under laboratory-simulated in situ conditions. In all, 106 isolated yeasts were identified by MSP-PCR fingerprinting and 26S rRNA gene sequencing of the D1/D2 region as belonging to 10 species: Aureobasidium pullulans, Cryptococcus gilvescens (over 50% of the total), Cryptococcus terricolus, Mrakia gelida, Naganishia globosa, Rhodotorula glacialis, Rhodotorula psychrophenolica, Rhodotorula bacarum, Rhodotorula creatinivora and Rhodotorula laryngis. Four strains, all belonging to a new yeast species, yet to be described, were also isolated.
Turchetti
Benedetta
B
Dipartimento di Biologia Applicata, Sezione di Microbiologia, University of Perugia, Borgo XX Giugno 74, Perugia, Italy.
Buzzini
Pietro
P
Goretti
Marta
M
Branda
Eva
E
Diolaiuti
Guglielmina
G
D'Agata
Carlo
C
Smiraglia
Claudio
C
Vaughan-Martini
Ann
A
D003080:Cold Temperature; D015169:Colony Count, Microbial; D003454:Cryptococcus / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification; D016172:DNA Fingerprinting / Q000379:methods; D004271:DNA, Fungal / Q000032:analysis; D019015:Geologic Sediments / Q000382:microbiology*; D046448:Ice Cover / Q000737:chemistry / Q000382:microbiology*; D007558:Italy; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012335:RNA, Ribosomal / Q000235:genetics; D012248:Rhodotorula / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification; D017422:Sequence Analysis, DNA; D015003:Yeasts / Q000145:classification / Q000235:genetics / Q000254:growth & development* / Q000302:isolation & purification
D004271:DNA, Fungal; D012335:RNA, Ribosomal; C065096:RNA, ribosomal, 26S