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 1C, subglacial sediments contained from 1.3x10^3 to 9.6x10^3 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 1C. Selected isolates were able to grow at 2 1C under laboratorysimulated 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.
Psychrophilic yeasts in glacial environments of Alpine glaciers
TURCHETTI, BENEDETTA;BUZZINI, Pietro;GORETTI, MARTA;BRANDA, EVA;VAUGHAN, Ann Elizabeth
2008
Abstract
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 1C, subglacial sediments contained from 1.3x10^3 to 9.6x10^3 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 1C. Selected isolates were able to grow at 2 1C under laboratorysimulated 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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
