A Short ERAP2 That Binds IRAP Is Expressed in Macrophages Independently of Gene Variation

The M1 zinc metalloproteases ERAP1, ERAP2, and IRAP play a role in HLA-I antigen presentation by refining the peptidome either in the ER (ERAP1 and ERAP2) or in the endosomes (IRAP). They have also been entrusted with other, although less defined, functions such as the regulation of the angiotensin system and blood pressure. In humans, ERAP1 and IRAP are commonly expressed. ERAP2 instead has evolved under balancing selection that maintains two haplotypes, one of which undergoing RNA splicing leading to nonsense-mediated decay and loss of protein. Hence, likewise in rodents, wherein the ERAP2 gene is missing, about a quarter of the human population does not express ERAP2. We report here that macrophages, but not monocytes or other mononuclear blood cells, express and secrete an ERAP2 shorter form independent of the haplotype. The generation of this “short” ERAP2 is due to an autocatalytic cleavage within a distinctive structural motif and requires an acidic micro-environment. Remarkably, ERAP2 “short” binds IRAP and the two molecules are co-expressed in the endosomes as well as in the cell membrane. Of note, the same phenomenon could be observed in some cancer cells. These data prompt us to reconsider the role of ERAP2, which might have been maintained in humans due to fulfilling a relevant function in its “short” form.     

Consequences of the Reproductive Effort of Dioecious Taxus baccata L. Females in a Generative Bud Removal Experiment—Important Role of Nitrogen in Female Reproduction

Dioecious species differ in the pattern and intensity of male and female reproductive investments. We aimed to determine whether female shoots deprived of generative buds show biochemical features, indicating their less-pronounced reproductive effort. For this purpose, the same branches of mature Taxus baccata females were deprived of generative organs. In the second and third years of the experiment, measurements were made in every season from the control and bud-removed shoots of females and control males. Bud removal caused an increase in nitrogen concentration almost to the level detected in the needles of male specimens, but only in current-year needles. Moreover, differences between male and control female shoots were present in the C:N ratio and increment biomass, but they disappeared when bud removal was applied to females. Additionally, between-sex differences were observed for content of phenolic compounds, carbon and starch, and SLA, independent of the female shoot reproductive effort. The study revealed that nitrogen uptake in seeds and arils may explain the lower nitrogen level and consequently the lower growth rate of females compared to males. At the same time, reproduction did not disturb carbon level in adjacent tissues, and two hypotheses explaining this phenomenon have been put forward.     

Cellular mechanism for the improvement of multiple stress tolerance in brewer's yeast by potassium ion supplementation

The ethanol fermentation efficiency was affected by multiple stress tolerance of yeast during brewing and bioethanol industry. The effect of KCl on the multiple stress tolerance of yeast cells was examined. Results showed that KCl addition significantly enhanced the tolerance of yeast cells to osmotic and ethanol stress, which correlated with the decreased membrane permeability, the increased intracellular ergosterol and ATP content, and the improved activity of complex II and complex III in yeast cells. Biomass and viability of yeast cells under osmotic and ethanol stress were increased significantly by KCl addition. Supplementation of 4 and 10 g L⁻¹ KCl exhibited the best promotion activity for yeast cells present in medium with 500 g L⁻¹ sucrose and 10% (v v⁻¹) ethanol, respectively. These results suggested that exogenous potassium addition might be an effective strategy to improve yeast tolerance and fermentation efficiency during industrial very-high-gravity (VHG) fermentation.     

Development of volatile profile of Kumpiak podlaski dry-cured ham during traditional ripening

Main aim of this research was to trace the development of volatile profile of Kumpiak podlaski dry-cured ham during traditional curing and ripening for 30 weeks. Volatiles were extracted from each 6-week period of ripening, and overall fifty-three aroma compounds were identified. Changes in chemical groups share between cured and fully ripened ham were observed: aldehydes (35.49 → 31.37%), ketones (25.18 → 14.62%), alcohols (17.97 → 15.74%), esters (3.37 → 12.04%), hydrocarbons (7.69 → 6.81%), fatty acids (0.02 → 0.53%), terpenes (2.26 → 9.70%) and heterocyclic aromatic compounds (0.99 → 0.78%). The 18th week of ripening is crucial for the aroma of Kumpiak podlaski ham due to start of continuous decrease in ketones and increase in esters’ and terpenes’ share. Formation of esters and terpenes originated from the presence of local herbs and the development of microflora. Principal component analysis (PCA) showed clear separation of samples from each 6-week period of ripening. Obtained results relying on thirty-seven compounds enabled to make a preliminary determination of ripening markers.     

Identifying Dense NiSe2/CoSe2 Heterointerfaces Coupled with Surface High-Valence Bimetallic Sites for Synergistically Enhanced Oxygen Electrocatalysis

Constructing heterostructures with abundant interfaces is essential for integrating the multiple functionalities in single entities. Herein, the synthesis of NiSe₂/CoSe₂ heterostructures with different interfacial densities via an innovative strategy of successive ion injection is reported. The resulting hybrid electrocatalyst with dense heterointerfaces exhibits superior electrocatalytic properties in an alkaline electrolyte, superior to other benchmarks and precious metal catalysts. Advanced synchrotron techniques, post structural characterizations, and density functional theory (DFT) simulations reveal that the introduction of atomic-level interfaces can lower the oxidation overpotential of bimetallic Ni and Co active sites (whereas Ni²⁺ can be more easily activated than Co²⁺) and induce the electronic interaction between the core selenides and surface in situ generated oxides/hydroxides, which play a critical role in synergistically reducing energetic barriers and accelerating reaction kinetics for catalyzing the oxygen evolution. Hence, the heterointerface structure facilitates the catalytic performance enhancement via increasing the intrinsic reactivity of metallic atoms and enhancing the synergistic effect between the inner selenides and surface oxidation species. This work not only complements the understanding on the origins of the activity of electrocatalysts based on metal selenides, but also sheds light on further surface and interfacial engineering of advanced hybrid materials.     

Relating variations in water saturation of a sandstone sample to pore geometry by neutron tomography and image analysis of thin sections

Neutron tomography experiments were undertaken on a quartz arenite sample in order to determine saturation variations in the sample after the initially water-saturated sample was subjected to air flushing. The experiments were carried out in order to study the applicability of the neutron tomography facility at the Paul Scherrer Institute, Switzerland, for imaging fluid distribution in porous rocks. The variation in water saturation was related to the pore geometry of the sample as investigated by petrographic image analysis of thin sections. A variation in fluid saturation was successfully imaged. The spatial saturation distribution noted from the neutron tomography corresponds well with variations in pore geometry, indicating that the water was preferentially flushed from the coarse-grained laminae. Résumé. Des mesures tomographiques neutroniques ont été réalisées sur un échantillon de grès quartzeux dans le but d'y déterminer des variations de degré de saturation après que l'échantillon initialement saturé en eau ait été soumis à un drainage forcé. Les expériences ont été conduites afin d'étudier la capacité d'un dispositif de tomographie neutronique de l'Institut Paul Scheerer (Suisse) à donner une image de la répartition des fluides dans les roches poreuses. Des variations de degré de saturation ont été identifiées avec succès, variations en relation avec la géométrie des pores de l'échantillon comme cela a pu être identifié par des techniques d'analyse d'image de lames minces. La répartition spatiale du degré de saturation observée à partir de la tomographie neutronique correspond bien à des variations dans la géométrie des pores, indiquant que l'eau avait été préférentiellement chassée des lamines constituées de gros grains. Electronic Publication     

The glyceridic and nonglyceridic constituents of virgin olive oil after use of a novel method of enzyme extraction

Summary The composition of three virgin olive oil varieties (Caroleo, Coratina and Leccino) was investigated after extraction with a new enzyme processing aid called Bioliva. Comparisons with reference oils extracted without using the biological preparation were made. The oils extracted by enzymes showed the following features: (i) higher contents of total phenols, o‐diphenols, major free and hydrolysable phenols, tocopherols, chlorophylls, pheophytins (Mg‐free chlorophyll derivatives), β‐carotene, major xanthophylls (lutein, violaxanthin and neoxanthin), agreeable volatiles, long‐chain aliphatic alcohols and superior triterpene alcohols; (ii) lower contents of disagreeable volatiles; (iii) higher sensory scoring and resistance to autoxidation; (iv) higher values of Naudet's integral colour index, carotenoid colour index, chroma and 1,2‐diglycerides/1,3‐diglycerides ratio and (v) lower values of lightness. These findings suggested that the oil's analytical pattern was meaningfully improved following this novel enzyme treatment.     

Efficient UV polymerisation of 3BCMU: Optical and waveguiding properties of the material

A modified method to synthesize 3BCMU and to polymerize it by ultraviolet (UV) radiation is presented; the polymerization technique gave a maximum yield of 18%. Langmuir-Blodgett and spin coated films of UV/poly-3BCMU have been fabricated. Visible and resonance Raman spectroscopy and waveguide tests were performed: the results are compared with those obtained with y/poly-3BCMU films.     

Continuous biotransformation of pyrogallol to purpurogallin using cross‐linked enzyme crystals of laccase as catalyst in a packed‐bed reactor

Cross‐linked enzyme crystals (CLEC) of laccase were prepared by crystallizing laccase with 75% (NH₄)₂SO₄ and cross‐linking using 1.5% glutaraldehyde. The cross‐linked enzyme crystals were further coated with 1 mmol L^?1 β‐cyclodextrin by lyophilization. The lyophilized enzyme crystals were used as such for the biotransformation of pyrogallol to purpurogallin in a packed‐bed reactor. The maximum conversion (76.28%) was obtained with 3 mmol L^?1 pyrogallol at a residence time of 7.1 s. The maximum productivity (269.03 g L^?1 h^?1) of purpurogallin was obtained with 5 mmol L^?1 pyrogallol at a residence time of 3.5 s. The productivity was found to be 261.14 g L^?1 h^?1 and 251.1 g L^?1 h^?1 when concentrations of 3 mmol L^?1 and 7 mmol L^?1 respectively were used. The reaction rate of purpurogallin synthesis was maximum (2241.94 mg purpurogallin mg^?1 CLEC h^?1) at a residence time of 3.5 s, when 5 mmol L^?1 pyrogallol was used as the substrate. The catalyst to product ratio calculated for the present biotransformation was 1:2241. The CLEC laccase had very high stability in reuse and even after 650 h of continuous use, the enzyme did not lose its activity. Copyright © 2006 Society of Chemical Industry     

Anaerobic degradation of polyethylene glycol mixtures

Anaerobic treatment of polyethylene glycol may represent an alternative to integrated chemical–biological treatment for the elimination of polyethylene glycol. Anaerobic biodegradation of synthetic waters are made with a mix of polyethylene glycol of molecular weights 400, 600 and 1000 and another made with polyethylene glycol of molecular weights 1500, 3000 and 10 000, was studied using an inoculum adapted to polyethylene glycol 10 000. The critical and minimum retention times were estimated and ranged from 13.2 to 14 and from 18 to 20 days, respectively. Under these operational conditions, the removal percentage ranged from 85 to 90%. Thus, anaerobic degradation of synthetic water containing polyethylene glycol produces removal percentages and hydraulic retention times similar to those of biodegradable wastewater tested at the same operational conditions. Copyright © 2003 Society of Chemical Industry