GUP1 and its close homologue GUP2, encoding multi-membrane-spanning proteins involved in active glycerol uptake in Saccharomyces cerevisiae

Many yeast species can utilise glycerol, both as sole carbon source and as an osmolyte. In Saccharomyces cerevisiae, physiological studies have previously shown the presence of an active uptake system driven by electrogenic proton symport. We have used transposon mutagenesis to isolate mutants affected in the transport of glycerol into the cell. Here we present the identification of YGL084c, encoding a multi-membrane-spanning protein, as being essential for proton symport of glycerol into Saccharomyces cerevisiae. The gene is named GUP1 (Glycerol UPtake) and is important for growth on glycerol as carbon and energy source, as well as for osmotic protection by added glycerol, of a strain deficient in glycerol production. Another ORF, YPL189w, presenting a high degree of homology to YGL084c, similarly appears to be involved in active glycerol uptake in salt-containing glucose-based media in strains deficient in glycerol production. Analogously, this gene is named GUP2. To our knowledge, this is the first report on a gene product involved in active transport of glycerol in yeasts. Mutations with the same phenotypes occurred in two other open reading frames of previously unknown function, YDL074c and YPL180w.Comunidade Europeia (CE) - contract BIO4-CT95-0161

The potential of alternative seed treatments to control anthracnose disease in white lupin

White lupin (Lupinus albus L.) is a promising crop to meet the rising global demand for plant-based protein. The seed-borne pathogen Colletotrichum lupini, however, threatens lupin cultivation worldwide. Seed dressings using synthetic fungicides were shown effective to reduce infection levels, but their negative environmental impact and exclusion from organic production calls for more sustainable solutions. In this study, a total of eleven different alternative seed treatments were tested in field trials in Switzerland between 2018 and 2021. Treatment types consisted of: hot water, steam, electron, long-term storage, elevated partial pressure of oxygen (EPPO), vinegar, plant extracts and biological control agents (BCAs). The BCAs were tested for potential antagonistic activity against C. lupini during white lupin infection under controlled conditions prior to field trials. Long-term storage and vinegar treatments successfully reduced disease incidence and increased yield to levels similar to those observed for certified seeds, without significantly affecting germination rate. Although promising, effectiveness of these treatments needs further validation. Four BCAs showed significant disease reductions under controlled conditions. Besides lowering disease severity, two BCAs also reduced C. lupini DNA in stem tissue. These reductions, however, were not observed in the field, highlighting the importance of field validations. The treatments identified in this study provide a solid basis for the development of sustainable and effective seed protection strategies in white lupin to control C. lupini successfully