Duffy blood group system - the frequency of Duffy antigen polymorphisms and novel mutations in the Polish population.

Duffy blood group genes are highly polymorphic with the distribution of alleles varying between different populations and ethnic groups. The aim of this study was to genotype Duffy blood group antigens and to establish FY alleles frequency in the Polish population and screen for novel FY gene mutations. Duffy phenotype and genotype frequencies analysis was based on studies of 596 persons. All these subjects were genotyped by high-resolution melting (HRM) method. It was shown that phenotype Fy(a+b+), defined by genotypes FY*A/FY*B (33%), FY*A/FY*B298A (13%), and FY*A/FY*02W.01 (2.8%) was the most common in Polish population (˜49%), followed by Fy(a-b+), ˜29%, determined by genotypes arising from FY*B allele and all its variants. Fy(a+b-) phenotype occurred with a frequency of 21.3% and was defined by the following genotypes: FY*A/A (21%), and FY*A/02N.01 (0.3%). Among the Polish population the frequencies of FY*A, FY*B, and FY*B298A alleles were 45.7%, 36% and 15.5%, respectively. The alleles FY*B298A and FY*B combined together, represented higher frequency (51%) than FY*A. Alleles FY*02W.01 and FY*02N.01 had frequencies 2.51% and 0.25%, respectively. The distribution of Duffy genotypes in the Polish population was in accordance with Hardy-Weinberg equilibrium (p = 0.9682). Alleles in the genotypes are independent from each other (r = 0.0278, R2 = 0.00077). New mutations identified in the promoter region (c.-79T > C) and the coding region of the FY gene (c.147C > A and c.175 G > A) did not affect the Duffy antigen expression on erythrocyte. Although FY alleles frequency is known in different populations, no data for Polish population is available.

Hydrogenation of Carbon Dioxide to Methane by Ruthenium Nanoparticles in Ionic Liquid.

The efficient transformation of carbon dioxide into fuels can be an excellent alternative to sequestration. In this work, we describe CO2 hydrogenation to methane in imidazolium-based ionic liquid media, using ruthenium nanoparticles prepared in situ as catalyst. The best yield of methane (69 %) was achieved using 0.24 mol % ruthenium catalyst (in [omim][NTf2 ], 1-octyl-3-methylimidazolium bistrifluoromethanesulfonylimide, at 40 bar of hydrogen pressure plus 40 bar of CO2 pressure, and at 150 °C.

[Duffy blood group antigens: structure, serological properties and function]. / Antygeny ukladu grupowego Duffy: budowa, wlasciwosci serologiczne i funkcja.

Duffy (Fy) blood group antigens are located on seven-transmembrane glycoprotein expressed on erythrocytes and endothelial cells, which acts as atypical chemokine receptor (ACKR1) and malarial receptor. The biological role of the Duffy glycoprotein has not been explained yet. It is suggested that Duffy protein modulate the intensity of the inflammatory response. The Duffy blood group system consists of two major antigens, Fy(a) and Fy(b), encoded by two codominant alleles designated FY*A and FY*B which differ by a single nucleotide polymorphism (SNP) at position 125G>A of the FY gene that results in Gly42Asp amino acid change in the Fy(a) and Fy(b) antigens, respectively. The presence of antigen Fy(a) and/or Fy(b) on the erythrocytes determine three Duffy-positive phenotypes: Fy(a+b-), Fy(a-b+) and Fy(a+b+), identified in Caucasian population. The Duffy-negative phenotype Fy(a-b-), frequent in Africans, but very rare in Caucasians, is defined by the homozygous state of FY*B-33 alleles. The FY*B-33 allele is associated with a SNP -33T>C in the promoter region of the FY gene, which suppresses erythroid expression of this gene without affecting its expression in other tissues. The FY*X allele, found in Caucasians, is correlated with weak expression of Fy(b) antigen. Fy(x) antigen differs from the native Fy(b) by the Arg89Cys and Ala100Thr amino acid substitutions due to SNPs: 265C>T and 298G>A in FY*B allele. The frequency of the FY alleles shows marked geographic disparities, the FY*B-33 allele is predominant in Africans, the FY*B in Caucasians, while the FY*A allele is dominant in Asians and it is the most prevalent allele globally.

High-resolution melting analysis for genotyping Duffy blood group antigens.

Antigens of the Duffy (Fy) blood group are significant in medical transfusions since they may cause serious post-transfusion reactions and hemolytic disease of the fetus and newborn. Results of serotyping performed on donors with reduced or abolished erythrocyte Duffy expression may be misleading, since the Duffy antigen is also present on non-erythroid cells. In such cases only DNA-based genotyping may reveal the actual Duffy antigen status. Here we describe the high-resolution melting (HRM) method for Duffy genotyping, which is a new post-PCR analysis method used for identifying genetic variations in nucleic acid sequences. It is based on the PCR melting curve technique where single nucleotide polymorphism (SNP) in DNA determines a characteristic shape of the melting curve and melting temperature (Tm) of a sample. HRM analysis for FY genotyping can discriminate SNPs in the FY gene through detection of small differences in melting profiles of variants when compared to controls. Recently, we have shown the usefulness of HRM analysis in elucidation of the molecular basis of Duffy-negative phenotype in a Polish family and in large-scale Duffy genotyping.

Pretreatment and fractionation of wheat straw using various ionic liquids.

Pretreatment of lignocellulosic biomass with ionic liquids (ILs) is a promising and challenging process for an alternative method of biomass processing. The present work emphasizes the examination of wheat straw pretreatment using ILs, namely, 1-butyl-3-methylimidazolium hydrogensulfate ([bmim][HSO4]), 1-butyl-3-methylimidazolium thiocyanate ([bmim][SCN]), and 1-butyl-3-methylimidazolium dicyanamide ([bmim][N(CN)2]). Only [bmim][HSO4] was found to achieve a macroscopic complete dissolution of wheat straw during pretreatment. The fractionation process demonstrated to be dependent on the IL used. Using [bmim][SCN], a high-purity lignin-rich material was obtained. In contrast, [bmim][N(CN)2] was a good solvent to produce high-purity carbohydrate-rich fractions. When [bmim][HSO4] was used, a different behavior was observed, exhibiting similarities to an acid hydrolysis pretreatment, and no hemicellulose-rich material was recovered during fractionation. A capillary electrophoresis (CE) technique allowed for a better understanding of this phenomenon. Hydrolysis of carbohydrates was confirmed, although an extended degradation of monosaccharides to furfural and hydroxymethylfurfural (HMF) was observed.

Pre-treatment of lignocellulosic biomass using ionic liquids: wheat straw fractionation.

This work is devoted to study pre-treatment methodologies of wheat straw with 1-ethyl-3-methylimidazolium acetate ([emim][CH3COO]) and subsequent fractionation to cellulose, hemicellulose and lignin. The method developed and described here allows the separation into high purity carbohydrate and lignin fractions and permits an efficient IL recovery. A versatility of the established method was confirmed by the IL reuse. The fractionation of completely dissolved biomass led to cellulose-rich and hemicellulose-rich fractions. A high purity lignin was also achieved. To verify the potential further applicability of the obtained carbohydrate-rich fractions, and to evaluate the pre-treatment efficiency, the cellulose fraction resulting from the treatment with [emim][CH3COO] was subjected to enzymatic hydrolysis. Results showed a very high digestibility of the cellulose samples and confirmed a high glucose yield for the optimized pre-treatment methodology.

Outlook on the phase equilibria of the innovative system of "protected glycerol": 1,4-dioxaspiro[4.5]decane-2-methanol and alternative solvents.

Fundamental data on 1,4-dioxaspiro[4.5]decane-2-methanol are scarce. This work presents the foremost systematic data on the solubility of 1,4-dioxaspiro[4.5]decane-2-methanol in sustainable solvents such as water and ionic liquids accompanied by the interpretation of interactions occurring in such binary systems. 1,4-Dioxaspiro[4.5]decane-2-methanol, here called protected glycerol, has been synthesized in order to protect the two hydroxyl groups of glycerol, thus avoiding the formation of side products in a specific process. A series of imidazolium salts accompanied by pyridinium, phosphonium, and ammonium ones with various types of counterions were used in this study. The liquid-liquid and solid-liquid equilibrium measurements in binary systems were carried out by using a dynamic method at atmospheric pressure over the temperature range from 273.00 to 378.30 K or below the boiling point of the solvent. Among all tested sustainable solvents, protected glycerol exhibited limited solubility, with only a few of them in the temperature range studied. The majority of the examined ionic liquids, either hydrophilic or hydrophobic, showed complete miscibility with this monohydroxyol. The Fourier-transform infrared (FTIR) spectroscopy studies of solute and solvents showing a miscibility gap and of their mixtures were performed to obtain insight into major inter- and intramolecular interactions in the investigated systems. Furthermore, the differential scanning calorimetry was used for the first time to determine the melting point, the enthalpy of melting, and the temperature and enthalpy of the solid-solid phase transition of 1-allyl-3-methylimidazolium chloride [Amim][Cl]. The results for the solubility of protected glycerol in sustainable solvents can be used to design future alternative reactions, such as telomerization with protected glycerol in ionic liquids for more specific building blocks and extraction/or separation that involves these mixtures.

The use of agroinfiltration for transient expression of plant resistance and fungal effector proteins in Nicotiana benthamiana leaves.

Agroinfiltration is a versatile, rapid and simple technique that is widely used for transient gene expression in plants. In this chapter we focus on its use in molecular plant pathology, and especially for the expression of plant resistance (R) and fungal avirulence (Avr) (effector) genes in leaves of Nicotiana benthamiana. Co-expression of an R gene with the corresponding Avr gene triggers host-defence responses that often culminate in a hypersensitive response (HR). This HR is visible as a necrotic sector in the infiltrated leaf area. Staining of the infiltrated leaves with trypan blue allows visual scoring of the HR. Furthermore, fusion of a fluorescent tag to the recombinant protein facilitates determination of its sub-cellular localization by confocal microscopy. The matching gene pair I-2 and Avr2, respectively from tomato and the fungal root-pathogen Fusarium oxysporum f. sp. lycopersici, is presented as a typical example.

Coiled-coil domain-dependent homodimerization of intracellular barley immune receptors defines a minimal functional module for triggering cell death.

Plants and animals have evolved structurally related innate immune sensors, designated NLRs, to detect intracellular nonself molecules. NLRs are modular, consisting of N-terminal coiled-coil (CC) or TOLL/interleukin-1 receptor (TIR) domains, a central nucleotide-binding (NB) domain, and C-terminal leucine-rich repeats (LRRs). The polymorphic barley mildew A (MLA) locus encodes CC-containing allelic immune receptors recognizing effectors of the pathogenic powdery mildew fungus. We report the crystal structure of an MLA receptor's invariant CC domain, which reveals a rod-shaped homodimer. MLA receptors also self-associate in vivo, but self-association appears to be independent of effector-triggered receptor activation. MLA CC mutants that fail to self-interact impair in planta cell death activity triggered by the CC domain alone and by an autoactive full-length MLA receptor that mimics its ATP-bound state. Thus, CC domain-dependent dimerization of the immune sensor defines a minimal functional unit and implies a role for the dimeric CC module in downstream immune signaling.

Insight into the phase equilibrium phenomena of systems containing dienes and dicyanamide ionic liquids as a new potential application.

This work presents a systematic investigation into liquid-liquid phase equilibria for systems containing three various ionic liquids and four dienes as they have not been reported yet. The systems employed in this study containing dicyanamide based ionic liquids and dienes reveal the phase envelopes that have a similar shape to binodal curves with the upper critical solution temperature. Generally, 1-methyl-3-octylimidazolium dicyanamide ([C(8)mim][DCA]) was found to be a better solvent for nonpolar dienes. The 1-butyl-3-methylimidazolium dicyanamide ([C(4)mim][DCA]) ionic liquid is a much worse solvent for 1,5-cyclooctadiene, 1,3-cyclooctadiene, 1,5-hexadiene, and 1,7-octadiene compared to other ionic liquids studied. The miscibility gaps shrink for a less polar [C(8)mim][DCA] or even more for 1-dodecyl-3-methylimidazolium dicyanamide ([C(12)mim][DCA]). In the range of the studied temperatures, the solubility of dienes is significantly higher compared to the solubility of the ionic liquids containing the shorter alkyl chain in the cation. The solubility of the presented dienes in ([C(4)mim][DCA]) ionic liquid is also relatively high and may reach up to 0.19 mol fraction of the diene. The attained results demonstrate that nonpolar compounds can be dissolved to some extent in highly charged and polar solvents such as ionic liquids.

The small heat shock protein 20 RSI2 interacts with and is required for stability and function of tomato resistance protein I-2.

Race-specific disease resistance in plants depends on the presence of resistance (R) genes. Most R genes encode NB-ARC-LRR proteins that carry a C-terminal leucine-rich repeat (LRR). Of the few proteins found to interact with the LRR domain, most have proposed (co)chaperone activity. Here, we report the identification of RSI2 (Required for Stability of I-2) as a protein that interacts with the LRR domain of the tomato R protein I-2. RSI2 belongs to the family of small heat shock proteins (sHSPs or HSP20s). HSP20s are ATP-independent chaperones that form oligomeric complexes with client proteins to prevent unfolding and subsequent aggregation. Silencing of RSI2-related HSP20s in Nicotiana benthamiana compromised the hypersensitive response that is normally induced by auto-active variants of I-2 and Mi-1, a second tomato R protein. As many HSP20s have chaperone properties, the involvement of RSI2 and other R protein (co)chaperones in I-2 and Mi-1 protein stability was examined. RSI2 silencing compromised the accumulation of full-length I-2 in planta, but did not affect Mi-1 levels. Silencing of heat shock protein 90 (HSP90) and SGT1 led to an almost complete loss of full-length I-2 accumulation and a reduction in Mi-1 protein levels. In contrast to SGT1 and HSP90, RSI2 silencing led to accumulation of I-2 breakdown products. This difference suggests that RSI2 and HSP90/SGT1 chaperone the I-2 protein using different molecular mechanisms. We conclude that I-2 protein function requires RSI2, either through direct interaction with, and stabilization of I-2 protein or by affecting signalling components involved in initiation of the hypersensitive response.

STANDing strong, resistance proteins instigators of plant defence.

Resistance (R) proteins are involved in specific pathogen recognition and subsequent initiation of host defence. Most R proteins are nucleotide binding - leucine rich repeat (NB-LRR) proteins, which form a subgroup within the STAND (signal transduction ATPases with numerous domains) family. Activity of these multi-domain proteins depends on their ability to bind and hydrolyse nucleotides. Since R protein activation often triggers cell-death tight regulation of activation is essential. Autoinhibition, which seems to be accomplished by intramolecular interactions between the various domains, is important to retain R proteins inactive. This review summarizes recent data on intra- and intermolecular interactions that support a model in which pathogen perception triggers a series of conformational changes, allowing the newly exposed NB domain to interact with downstream signalling partners and activate defence signalling.