The field of systems biology is often held back by difficulties in obtaining comprehensive, highquality, quantitative data sets. In this paper, we undertook an interlaboratory effort to generate such a data set for a very large number of cellular components in the yeast Saccharomyces cerevisiae, a widely used model organism that is also used in the production of fuels, chemicals, food ingredients and pharmaceuticals. With the current focus on biofuels and sustainability, there is much interest in harnessing this species as a general cell factory. In this study, we characterized two yeast strains, under two standard growth conditions. We ensured the high quality of the experimental data by evaluating a wide range of sampling and analytical techniques. Here we show significant differences in the maximum specific growth rate and biomass yield between the two strains. on the basis of the integrated analysis of the highthroughput data, we hypothesize that differences in phenotype are due to differences in protein metabolism.

Background: Characterization of cellular growth is central to understanding living systems. Here, we applied a three-factor design to study the relationship between specific growth rate and genome-wide gene expression in 36 steady-state chemostat cultures of Saccharomyces cerevisiae. The three factors we considered were specific growth rate, nutrient limitation, and oxygen availability.

Purpose In the food chain the identification of household food wastes represents the most problematic aspect to analyze: both as regards the assessment of its qualitative and quantitative aspects and for the detection of measures to reduce or control its generation. In 2012, in fact, the analyzed area showed an inequality index for disposable income of 6.3, and a relative poverty risk index of 42.3. The paper aims to discuss these issues. Design/methodology/approach In order to get deeper insights into consumers’ wasting behaviors, a survey on food waste generation in households was carried out in a province of Sicily (Italy). The questionnaire has been formulated taking into account the socio-demographic characteristics for the person who, in the family, usually makes the expenditure, in particular: gender, age, marital status, number of household members, education level, type (single, with or without children, married with or without children), worker and/or student if responsible for food shopping, the number of monthly meals, the kind of ready meal eaten (frozen, fresh, canned or freeze-dried), net monthly income for the family, etc. (adapted by Bae et al., 2010). The data collected from the statistical return of the consumers were drawn up to transform the same data into information of simpler and more concise interpretation. Findings The results of the survey are presented in this paper. They can help understand the reasons for discarding edible food and to identify the food groups that are most wasted. Research limitations/implications The analysis of a larger land area or community allows most relevant conclusions. The research has an exploratory perspective since the sample strategy is not probabilistic. Social implications The findings could be susceptible to support practical and social implications for the identification of measures and instruments aimed at reducing food waste and at increasing consumers’ awareness on that issue. Originality/value The study can stimulate sustainable consumption and consumer behavior especially in light of the current economic crisis.

The objective of this study was the application of the synthetic promoter library (SPL) technology for modulation of actinorhodin production in Streptomyces coelicolor A3(2). The SPL technology was used to optimize the expression of a pathway specific positive transcriptional regulator ActII orf4, which activates the transcription of the S. coelicolor actinorhodin biosynthetic gene cluster. The native actII orf4 promoter was replaced with synthetic promoters, generating a S. coelicolor library with a broad range of expression levels of actII orf4. The resulting library was screened based on the yield of actinorhodin. Selected strains were further physiologically characterized. One of the strains from the library, ScoSPL20, showed considerably higher yield of actinorhodin and final actinorhodin titer, compared to S. coelicolor wild type and S. coelicolor with actII orf4 expressed from a strong constitutive promoter. ScoSPL20 demonstrated exceptional productivity despite having a comparatively weak expression from the promoter. Interestingly, the ScoSPL20 promoter was activated at a much earlier stage of growth compared to the wild type, demonstrating the advantage of fine-tuning and temporal tuning of gene expression in metabolic engineering. Transcriptome studies were performed in exponential and actinorhodin-producing phase of growth to compare gene expression between ScoSPL20 and the wild type. To our knowledge, this is the first successful application of the SPL technology for secondary metabolite production in filamentous bacteria.

The essential yeast kinases Mec1 and Rad53, or human ATR and Chk1, are crucial for checkpoint responses to exogenous genotoxic agents, but why they are also required for DNA replication in unperturbed cells remains poorly understood. Here we report that even in the absence of DNA-damaging agents, the rad53-4AQ mutant, lacking the N-terminal Mec1 phosphorylation site cluster, is synthetic lethal with a deletion of the RAD9 DNA damage checkpoint adaptor. This phenotype is caused by an inability of rad53-4AQ to activate the downstream kinase Dun1, which then leads to reduced basal deoxynucleoside triphosphate (dNTP) levels, spontaneous replication fork stalling, and constitutive activation of and dependence on S phase DNA damage checkpoints. Surprisingly, the kinase-deficient rad53-K227A mutant does not share these phenotypes but is rendered inviable by additional phosphosite mutations that prevent its binding to Dun1. The results demonstrate that ultralow Rad53 catalytic activity is sufficient for normal replication of undamaged chromosomes as long as it is targeted toward activation of the effector kinase Dun1. Our findings indicate that the essential S phase function of Rad53 is comprised by the combination of its role in regulating basal dNTP levels and its compensatory kinase function if dNTP levels are perturbed.

BackgroundAddition of sugar syrups to the basic wort is a popular technique to achieve higher gravity in beer fermentations, but it results in dilution of the free amino nitrogen (FAN) content in the medium. The multicomponent protease enzyme Flavourzyme has beneficial effect on the brewer's yeast fermentation performance during high gravity fermentations as it increases the initial FAN value and results in higher FAN uptake, higher specific growth rate, higher ethanol yield and improved flavour profile.ResultsIn the present study, transcriptome and metabolome analysis were used to elucidate the effect on the addition of the multicomponent protease enzyme Flavourzyme and its influence on the metabolism of the brewer's yeast strain Weihenstephan 34/70. The study underlines the importance of sufficient nitrogen availability during the course of beer fermentation. The applied metabolome and transcriptome analysis allowed mapping the effect of the wort sugar composition on the nitrogen uptake.ConclusionBoth the transcriptome and the metabolome analysis revealed that there is a significantly higher impact of protease addition for maltose syrup supplemented fermentations, while addition of glucose syrup to increase the gravity in the wort resulted in increased glucose repression that lead to inhibition of amino acid uptake and hereby inhibited the effect of the protease addition.