In enology, "Brett" character refers to the wine spoilage caused by the yeast Dekkera/Brettanomyces bruxellensis and its production of volatile phenolic off-flavours. However, the spoilage potential of this yeast is strain-dependent. Therefore, a rapid and reliable recognition at the strain level is a key point to avoid serious economic losses. The present work provides an operative tool to assess the genetic intraspecific variation in this species through the use of introns as molecular targets. Firstly, the available partial D./B. bruxellensis genome sequence was investigated in order to build primers annealing to introns 5' splice site sequence (ISS). This analysis allowed the detection of a non-random vocabulary flanking the site and, exploiting this feature, the creation of specific probes for strain discrimination. Secondly, the separation of the intron splice site PCR fragments was obtained throughout the set up of a capillary electrophoresis protocol, giving a 94% repeatability threshold in our experimental conditions. The comparison of results obtained with ISS-PCR/CE versus the ones performed by mtDNA RFLP revealed that the former protocol is more discriminating and allowed a reliable identification at strain level. Actually sixty D./B. bruxellensis isolates were recognised as unique strains, showing a level of similarity below 79% and confirming the high genetic polymorphism existing within the species. Two main clusters were grouped at similarity levels of about 46% and 47%, respectively, showing a poor correlation with the geographic area of isolation. Moreover, from the evolutionary point of view, the proposed technique could determine the frequency of the genome rearrangements that can occur in D./B. bruxellesis populations.
Intraspecific variations of Dekkera/Brettanomyces bruxellensis genome studied by capillary electrophoresis separation of the intron splice site profiles / I. Vigentini, G. De Lorenzis, C. Picozzi, S. Imazio, A. Merico, S. Galafassi, J. Piškur, R. Foschino. - In: INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY. - ISSN 0168-1605. - 157:1(2012), pp. 6-15.
|Titolo:||Intraspecific variations of Dekkera/Brettanomyces bruxellensis genome studied by capillary electrophoresis separation of the intron splice site profiles|
|Parole Chiave:||capillary electrophoresis separation; intron splice site; wine spoilage; yeast typing; Brettanomyces; intron|
|Settore Scientifico Disciplinare:||Settore AGR/16 - Microbiologia Agraria|
Settore CHIM/11 - Chimica e Biotecnologia delle Fermentazioni
Settore AGR/03 - Arboricoltura Generale e Coltivazioni Arboree
|Data di pubblicazione:||2012|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1016/j.ijfoodmicro.2012.02.017|
|Appare nelle tipologie:||01 - Articolo su periodico|