Metabolomic Comparison of Saccharomyces cerevisiae and the Cryotolerant Species S. bayanus var. uvarum and S. kudriavzevii during Wine Fermentation at Low Temperature

Temperature is one of the most important parameters affecting the length and rate of alcoholic fermentation and final wine quality. Wine produced at low temperature is often considered to have improved sensory qualities. However, there are certain drawbacks to low temperature fermentations such as reduced growth rate, long lag phase, and sluggish or stuck fermentations. To investigate the effects of temperature on commercial wine yeast, we compared its metabolome growing at 12°C and 28°C in a synthetic must. Some species of the Saccharomyces genus have shown better adaptation at low temperature than Saccharomyces cerevisiae. This is the case of the cryotolerant yeasts Saccharomyces bayanus var. uvarum and Saccharomyces kudriavzevii. In an attempt to detect inter-specific metabolic differences, we characterized the metabolome of these species growing at 12°C, which we compared with the metabolome of S. cerevisiae (not well adapted at low temperature) at the same temperature. Our results show that the main differences between the metabolic profiling of S. cerevisiae growing at 12°C and 28°C were observed in lipid metabolism and redox homeostasis. Moreover, the global metabolic comparison among the three species revealed that the main differences between the two cryotolerant species and S. cerevisiae were in carbohydrate metabolism, mainly fructose metabolism. However, these two species have developed different strategies for cold resistance. S. bayanus var. uvarum presented elevated shikimate pathway activity, while S. kudriavzevii displayed increased NAD+ synthesis. © 2013 López-Malo et al.This work has been financially supported by the grants AGL2010-22001-C02-01 and AGL2009-12673-C02-01, from the Spanish government, awarded to JMG and AQ, respectively; PROMETEO/2009/019 and ACOMP/2012/014 from Generalitat Valenciana, awarded to AQ and JMG, respectively. MLM also wishes to thank the Spanish government for her FPI grant.Peer Reviewe

Molecular analysis of the genes involved in aroma synthesis in the species S. cerevisiae, S. kudriavzevii and S. bayanus var. uvarum in winemaking conditions

The Saccharomyces genus is the main yeast involved in wine fermentations to play a crucial role in the production and release of aromatic compounds. Despite the several studies done into the genome-wide expression analysis using DNA microarray technology in wine S. cerevisiae strains, this is the first to investigate other species of the Saccharomyces genus. This research work investigates the expression of the genes involved in flavor compound production in three different Saccharomyces species (S. cerevisiae, S. bayanus var. uvarum and S. kudriavzevii ) under low (12°C) and moderate fermentation temperatures (28°C). The global genes analysis showed that 30% of genes appeared to be differently expressed in the three cryophilic strains if compared to the reference strain (mesophilic S. cerevisiae), suggesting a very close cold adaptation response. Remarkable differences in the gene expression level were observed when comparing the three species, S. cerevisiae, S. bayanus var. uvarum and S. kudriavzevii, which will result in different aroma profiles. Knowledge of these differences in the transcriptome can be a tool to help modulate aroma to create wines with the desired aromatic traits. © 2014 Gamero et al.AGL2009-12673-CO2-01, AGL2012-39937-C02-01 and from the Spanish Government and PROMETEO grant (Project PROMETEO/2009/019) from the Generalitat Valenciana to A. Querol. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer Reviewe

230th ENMC International Workshop: : Improving future assessment and research in IgM anti-MAG peripheral neuropathy: A consensus collaborative effort, Naarden, The Netherlands, 24-26 February 2017

The 230th European Neuromuscular Center (ENMC) international workshop occurred in Naarden, the Netherlands, from February 24th to 26th, 2017. The aims of the workshop were: 1) to create an IgM associated peripheral neuropathy study group and achieve consensus regarding the registration of patients with IgM associated peripheral neuropathy in a patient-based registry, 2) to improve future assessment of patients with IgM associated peripheral neuropathy from hematological markers to clinical trials, and 3) to discuss promising therapies for future clinical trials. Seventeen clinicians and researchers (sixteen neurologists and one hematologist) from nine countries (Belgium, Curaçao, France, Italy, the Netherlands, Spain, Switzerland, the United Kingdom, and the United States of America) were present. A patient with IgM associated peripheral neuropathy, a representative of the GBS/CIDP Foundation International, and a PhD student, who received support from the ENMC Young Scientist Program, also attended