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AbstractCumulus‐intact and ‐denuded unfertilized oocytes from two mouse strains were exposed to 1.5 m ethanol (EtOH) or two cryoproteclant solutions, 1.5 M propanediol (PROH) or 1.5 M dimethylsulfoxide (DMSO), for 4.5 min at 27°C, and the proportion of activating or degenerating oocytes studied. Exposure to DMSO did not significantly increase activation above that of oocytes not exposed to DMSO. Treatment of oocytes in PROH resulted in the activation of up to 87% of viable oocytes. This was significantly higher (P <01) than in control oocytes and comparable to the rate of activation after treatment with EtOH (59–96% activation). In solutions at 1°C, 47% of control oocytes were activated, which was not significantly different from the rate of activation in EtOH (36%) or PROH (50%) at 1°C. Following treatment with PROH, up to 87% of oocytes degenerated within a period of 6 h in vitro. The age of the oocytes (h post hCG) and the time of cumulus removal with the enzyme hyaluronidase, relative to the time of exposure to the chemicals, influenced the level of degeneration in most groups. Significantly fewer oocytes degenerated when cumulus cells were removed before treatment (0–31%) than when the cumulus was left intact throughout the treatment and 6 h culture period (10–87%). Exposure to PROH at 1°C reduced oocyte degeneration to 5%. We conclude that PROH causes significantly greater losses of oocytes as a result of parthenogenetic activation and degeneration than of exposure to DMSO.

An energy-saving ethanol fermentation technology was developed using uncooked fresh sweet potato as raw material. A mutant strain of Aspergillus niger isolated from mildewed sweet potato was used to produce abundant raw starch saccharification enzymes for treating uncooked sweet potato storage roots. The viscosity of the fermentation paste of uncooked sweet potato roots was lower than that of the cooked roots. The ethanol fermentation was carried out by Zymomonas mobilis, and 14.4 g of ethanol (87.2% of the theoretical yield) was produced from 100g of fresh sweet potato storage roots. Based on this method, an energy-saving, high efficient and environment-friendly technology can be developed for large-scale production of fuel ethanol from sweet potato roots.

Abstract. Regional land carbon budgets provide insights on the spatial distribution of the land uptake of atmospheric carbon dioxide, and can be used to evaluate carbon cycle models and to define baselines for land-based additional mitigation efforts. The scientific community has been involved in providing observation-based estimates of regional carbon budgets either by downscaling atmospheric CO2 observations into surface fluxes with atmospheric inversions, by using inventories of carbon stock changes in terrestrial ecosystems, by upscaling local field observations such as flux towers with gridded climate and remote sensing fields or by integrating data-driven or process-oriented terrestrial carbon cycle models. The first coordinated attempt to collect regional carbon budgets for nine regions covering the entire globe in the RECCAP-1 project has delivered estimates for the decade 2000–2009, but these budgets were not comparable between regions, due to different definitions and component fluxes reported or omitted. The recent recognition of lateral fluxes of carbon by human activities and rivers, that connect CO2 uptake in one area with its release in another also requires better definition and protocols to reach harmonized regional budgets that can be summed up to the globe and compared with the atmospheric CO2 growth rate and inversion results. In this study, for the international initiative RECCAP-2 coordinated by the Global Carbon Project, which aims as an update of regional carbon budgets over the last two decades based on observations, for 10 regions covering the globe, with a better harmonization that the precursor project, we provide recommendations for using atmospheric inversions results to match bottom-up carbon accounting and models, and we define the different component fluxes of the net land atmosphere carbon exchange that should be reported by each research group in charge of each region. Special attention is given to lateral fluxes, inland water fluxes and land use fluxes.

As atmospheric levels of CO(2) increase, reef-building corals are under greater stress from both increased sea surface temperatures and declining sea water pH. To date, most studies have focused on either coral bleaching due to warming oceans or declining calcification due to decreasing oceanic carbonate ion concentrations. Here, through the use of physiology measurements and cDNA microarrays, we show that changes in pH and ocean chemistry consistent with two scenarios put forward by the Intergovernmental Panel on Climate Change (IPCC) drive major changes in gene expression, respiration, photosynthesis and symbiosis of the coral, Acropora millepora, before affects on biomineralisation are apparent at the phenotype level. Under high CO(2) conditions corals at the phenotype level lost over half their Symbiodinium populations, and had a decrease in both photosynthesis and respiration. Changes in gene expression were consistent with metabolic suppression, an increase in oxidative stress, apoptosis and symbiont loss. Other expression patterns demonstrate upregulation of membrane transporters, as well as the regulation of genes involved in membrane cytoskeletal interactions and cytoskeletal remodeling. These widespread changes in gene expression emphasize the need to expand future studies of ocean acidification to include a wider spectrum of cellular processes, many of which may occur before impacts on calcification.

We present the wavelength dependence of homogeneous holewidths of persistent spectral holes burnt in O2-evolving Photosystem II core complexes isolated from spinach, in the temperature range 2.5-8 K. The data supports the assignment that those chlorophylls which undergo persistent spectral hole-burning are specific CP43 and CP47-trap states that transfer their excitation energy to the reaction center. The lifetime-limited holewidths show that when PS II is in the S1(QA -) (closed) state, the CP43/CP47-trap states have excited-state lifetimes in the range from 70 to 270 ps. These lifetimes correspond to excitation transfer rates to the reaction center, and are far slower than required for models in which the PS II reaction center (P680) acts as a 'shallow-trap' for excitations. For wavelengths at which both traps absorb, the hole shape is clearly a composite of two Lorentzians, corresponding to hole-burning in both states simultaneously. The temperature dependence of the homogeneous holewidth does not follow the usual T1.3 dependence found in many chlorophyll-protein systems. Our data indicates T 2 temperature dependence, typically found in crystalline systems where the chromophore is coupled to localized phonon modes.

Anaphylactic reactions to ethanol are rare with only seven cases reported in the literature. All previous cases have occurred following ingestion of alcoholic beverages or food to which an alcoholic beverage has been added. To date there are no cases in the literature of ethanol-induced anaphylaxis caused by the accumulation of endogenous ethanol in overripe fruit.We report a patient with ethanol-induced anaphylaxis who developed anaphylaxis following ingestion of overripe, but not fresh rock melon (Cucumis melo). The patient is a 24-year-old, previously well woman who experienced five episodes of acute anaphylaxis following ingestion of various alcoholic beverages and, on one occasion, following ingestion of overripe rock melon to which no ethanol was added. Ethanol-induced anaphylaxis was confirmed on blinded challenge; however, challenge with freshly prepared rock melon was negative. The patient declined further challenges.Ingestion of overripe fruits may cause anaphylaxis in patients with ethanol-induced anaphylaxis. These patients should therefore, be advised to avoid ingestion of overripe fruits.

Abstract Background As a strong fermentator, Saccharomyces cerevisiae has the potential to be an excellent host for ethanol production by consolidated bioprocessing. For this purpose, it is necessary to transform cellulose genes into the yeast genome because it contains no cellulose genes. However, heterologous protein expression in S. cerevisiae often suffers from hyper-glycosylation and/or poor secretion. Thus, there is a need to genetically engineer the yeast to reduce its glycosylation strength and to increase its secretion ability. Results Saccharomyces cerevisiae gene-knockout strains were screened for improved extracellular activity of a recombinant exocellulase (PCX) from the cellulose digesting fungus Phanerochaete chrysosporium. Knockout mutants of 47 glycosylation-related genes and 10 protein-trafficking-related genes were transformed with a PCX expression construct and screened for extracellular cellulase activity. Twelve of the screened mutants were found to have a more than 2-fold increase in extracellular PCX activity in comparison with the wild type. The extracellular PCX activities in the glycosylation-related mnn10 and pmt5 null mutants were, respectively, 6 and 4 times higher than that of the wild type; and the extracellular PCX activities in 9 protein-trafficking-related mutants, especially in the chc1, clc1 and vps21 null mutants, were at least 1.5 times higher than the parental strains. Site-directed mutagenesis studies further revealed that the degree of N-glycosylation also plays an important role in heterologous cellulase activity in S. cerevisiae. Conclusions Systematic screening of knockout mutants of glycosylation- and protein trafficking-associated genes in S. cerevisiae revealed that: (1) blocking Golgi-to-endosome transport may force S. cerevisiae to export cellulases; and (2) both over- and under-glycosylation may alter the enzyme activity of cellulases. This systematic gene-knockout screening approach may serve as a convenient means for increasing the extracellular activities of recombinant proteins expressed in S. cerevisiae.