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Methanotrophs are the sole biological sink of methane. Volatile organic compounds (VOCs) produced by heterotrophic bacteria have been demonstrated to be a potential modulating factor of methane consumption. Here, we identify and disentangle the impact of the volatolome of heterotrophic bacteria on the methanotroph activity and proteome, using Methylomonas as model organism. Our study unambiguously shows how methanotrophy can be influenced by other organisms without direct physical contact. This influence is mediated by VOCs (e.g. dimethyl-polysulphides) or/and CO2 emitted during respiration, which can inhibit growth and methane uptake of the methanotroph, while other VOCs had a stimulating effect on methanotroph activity. Depending on whether the methanotroph was exposed to the volatolome of the heterotroph or to CO2, proteomics revealed differential protein expression patterns with the soluble methane monooxygenase being the most affected enzyme. The interaction between methanotrophs and heterotrophs can have strong positive or negative effects on methane consumption, depending on the species interacting with the methanotroph. We identified potential VOCs involved in the inhibition while positive effects may be triggered by CO2 released by heterotrophic respiration. Our experimental proof of methanotroph–heterotroph interactions clearly calls for detailed research into strategies on how to mitigate methane emissions.

Istaživanje u okviru ove doktorske disertacije je imalo za cilj utvrđivanje uticaja različitih agroekoloških uslova na produktivnost i prinos genotipova proteinskog graška (kroz utvrđivanje fenotipskih razlika između genotipova, vrednosti komponenti prinosa semena, sadržaja i prinosa proteina i analizu sastava proteina u semenu), analizu korelacije između sadržaja proteina u semenu sa komponentama prinosa i prinosom semena, sa glavnim ciljem da se dobiju rezultati koji će poslužiti kao osnova i pokazatelj za utvrđivanje osobina koje utiču na prinos proteina. U tom cilju postavljeni su ogledi na dva lokaliteta tokom dve godine – na oglednom polju Instituta za ratarstvo i povrtarstvo u Novom Sadu, Republika Srbija, i na oglednom polju kompanije Agro Seed Research, Kessenich, Belgija, po eksperimentalnom planu sa delimičnim ponavljanjima (Augmented design) u red-kolona sistemu, sa četiri eksperimentalna bloka. Za istraživanje korišćeno je ukupno 165 genotipova graška, pri čemu su ispitivani genotipovi podeljeni u dve grupe, prema tipu (sorte, linije, eksperimentalne linije, divlji i poludivlji srodnici) i prema upotrebi (povrtarski, za zrno, krmni, eksperimentalne linije i divlji srodnici)., The research involved evaluating phenotypic variations between genotypes, analyzing seed yield components, protein content, and yield, and conducting a protein composition analysis. Multivariate and correlation analysis were performed to examine the relationship between protein content, yield components, and seed yield, with the primary goal of identifying traits that impact protein yield. Experiments were conducted over two years at two locations: the Institute for Crop and Vegetable Agriculture in Novi Sad, Republic of Serbia, and the experimental field of the Agro Seed Research company in Kessenich, Belgium. The experimental design included four blocks with partial repetitions, following an augmented design in a row-column system. A total of 165 pea genotypes were evaluated, and categorized based on type (varieties, lines, experimental lines, wild and semi-wild relatives) and use (vegetable, grain, fodder, experimental lines, and wild relatives).

Temperature, perhaps more than any other environmental factor, is likely to influence the evolution of all organisms. It is also a very interesting factor to understand how genomes are shaped by selection over evolutionary timescales, as it potentially affects the whole genome. Among thermophilic prokaryotes, temperature affects both codon usage and protein composition to increase the stability of the transcriptional/translational machinery, and the resulting proteins need to be functional at high temperatures. Among eukaryotes less is known about genome evolution, and the tube-dwelling worms of the family Alvinellidae represent an excellent opportunity to test hypotheses about the emergence of thermophily in ectothermic metazoans. The Alvinellidae are a group of worms that experience varying thermal regimes, presumably having evolved into these niches over evolutionary times. Here we analyzed 423 putative orthologous loci derived from 6 alvinellid species including the thermophilic Alvinella pompejana and Paralvinella sulfincola. This comparative approach allowed us to assess amino acid composition, codon usage, divergence, direction of residue changes and the strength of selection along the alvinellid phylogeny, and to design a new eukaryotic thermophilic criterion based on significant differences in the residue composition of proteins. Contrary to expectations, the alvinellid ancestor of all present-day species seems to have been thermophilic, a trait subsequently maintained by purifying selection in lineages that still inhabit higher temperature environments. In contrast, lineages currently living in colder habitats likely evolved under selective relaxation, with some degree of positive selection for low-temperature adaptation at the protein level.

Pressed cake from rapeseed (Brassica napus L.) is a promising plant protein source not yet utilised for human consumption due to the presence of antinutrients such as glucosinolates. Protein solubility is a crucial parameter influencing the functionality and thereby the applicability of proteins as food ingredients. A novel cruciferin-rich rapeseed protein product was produced by an aqueous processing method in pilot plant scale. Intact glucosinolates were conserved by this procedure and largely removed from the protein products. Protein solubility in this product was examined when dispersed in 50 mm phosphate buffer, pH 8.0 with varying NaCl concentration (0-500 mm). Unexpectedly, a salting-out effect was observed of the globulin proteins, as 15.9 ± 0.6% protein was in solution at 500 mm added NaCl, whereas 21.5 ± 1.1% was solubilised without added NaCl; whether the observed effects originates from lipid and fibre constituents in the product remains to be resolved.

Europe produces 14% of the worldwide meat resulting in a high demand for protein rich feed sources like soy. Soy cannot grow in the European climate and the major part is imported from outside Europe which is costly and gives an extra load to the environment. Duckweed is considered as an alternative protein feed source, able to grow in the European climate. In ECOFERM!, duckweed was fed to the calves to limit the amount soy used. ECOFERM ! is a closed - cycle farm in which by - products from rosé calf farming are used to produce duckweed and biogas. ECOFERM ! is tackling problems with manure regulations and reduc es soy import. However, the production of duckweed turned out to be too expensive for the extra value direct feeding created. Duckweed is used inefficiently when fed directly to calves. Processing of duckweed in a bioref inery can solve this problem trying to maximize all the chemical compounds in duckweed.

Extraction of protein-derived thiols by protease treatment during mashing for improvement of flavor stability in beer has previously been shown to cause concomitant increase in free amino acid concentrations and thereby increased levels of unwanted Maillard reaction products during aging. The previous methodology, with addition of protease dosed at 50 mg of enzyme/kg of malt at the beginning of the protein rest during mashing, resulted in increased amino acid concentrations of approximately 40% and increased free thiol concentrations of approximately 50% in wort compared with a control without protease addition. The objective of this study was to reduce the amount of amino acids in wort obtained by protease treatment but still obtain a significant increase in protein-derived thiols. In this paper we demonstrate that by omitting the protein rest during mashing in combination with addition of a protease with a higher temperature optimum dosed at only 3 mg of enzyme/kg of malt, it is possible to increase thiol concentrations in wort by 30% and with only a maximum 10% increase in amino acid concentration compared with a control. Pilot brewing showed that beer brewed with addition of protease resulted in a 30% increase in total thiol concentration, along with a decrease in or no effect on the concentration of some amino acids but also an increase in the concentration of other amino acids. Sulfite concentration was increased by 37%, so the effect of increasing free thiol concentration on flavor stability during storage could not be evaluated. Overall, similar brewing and sensory characteristics were obtained compared with a control beer brewed without addition of protease. Foam stability was decreased by protease treatment, and formation of haze was reduced by protease treatment.

Cynaeus angustus (LeConte) is characterized as a pest of stored grain, there is several food substrates on their feeding ecology including corn, wheat, sorghum and soybeans. But there is no record of their habits in peanut in natura, so the aim of this study was to present the static life table, to C. angustus in laboratory conditions using as substrate the peanut, and evaluate the protein composition in different stages of development C. angustus. The quantification of proteins was taken by microbiureto method and qualitative method was done per electrophoretic method. Protein quantitation indicated an increase of its values during development of insects: larvae 38,22 mg/mL, pupae 47,53 mg/mL and adults 60,00 mg/mL. It was possible to observe the electrophoretic profile C. angustus showed a significant increase in the variety of proteins (29-700 kDa) on the different stages of the insect. Data obtained from the population analysis indicate that C. angustus shows higher initial survival rates, high biotic potential and continuous developing in favorable conditions showing potential growing conditions and, that can be used as a nutritional source such as mentioned for other species of the same family., Cynaeus angustus (LeConte) caracteriza-se como praga de grãos armazenados, possui diversos substratos alimentares listados em sua ecologia alimentar entre eles o milho, trigo, sorgo e soja. Porém não há registro de seus hábitos no amendoim in natura, assim o objetivo deste estudo foi apresentar a tabela de vida estática, para C. Angustus em condições de laboratório utilizando como substrato o amendoim, e avaliar a composição proteica nos diferentes estádios de desenvolvimento de C. angustus. A quantificação de proteínas foi feita pelo método de microbiureto e o método qualitativo foi feito per método eletroforético. Assim a quantificação de proteínas indicou um aumento de seus valores durante o desenvolvimento dos insetos: larvas 38,22 mg/mL, pupas 47,53 mg/mL e adultos de 60.00 mg/mL. Foi possível observar o perfil electroforético de C. angustus indicando um aumento significativo na variedade de proteínas (29 a 700 kDa) sobre as diferentes etapas deste inseto. Os dados obtidos pela analise populacional indicam que C. angustus apresenta maiores taxas iniciais de sobrevivência, alto potencial biótico e desenvolvimento contínuo em condições favoráveis que mostram potenciais condições de cultivo e pode ser usado como uma fonte nutricional tal como mencionado para outras espécies da mesma família.

The photosynthetic thylakoid membrane has a hierarchically ordered structure containing pigment-protein complexes that capture solar radiation and convert it into chemical energy. Its highly dynamic structure is capable to continuously respond to the altered environmental conditions, e.g., light quality and quantity, temperature changes and nutrient availability. Having detailed knowledge about the photosynthetic apparatus and its regulating factors is of paramount importance for the potential use of photosynthesis as alternative energy source or for removing toxic pollutants. The thesis provides new information about the role of various carotenoid molecules for the structure and energy transfer capacity of photosynthetic complexes in cyanobacteria. Our results demonstrate that besides the known structural importance of carotenoids they are also required for the oligomerisation of photosystems and for maintaining the structure of the light-harvesting antenna complexes, called phycobilisomes. Part of the thesis focuses on the Photosystem II (PSII) macro-organisation in the chloroplast thylakoid membrane of plants. The general importance of a small-molecular-weight protein, PsbW is demonstrated for the organisation of the PSII supercomplexes and the formation of the parallel rows of PSII and the accompanying psi-type circular dichroism signal. A new, circular dichroism (CD) spectroscopy-based fingerprinting method is described that can be used to study the PSII macrodomain organization. CD is a potentially powerful method to follow the dynamic changes of the pigment-protein complex organisation of chloroplast membranes in vivo. In this thesis the cadmium-induced toxic effects on photosynthetic processes are also investigated. The observed changes can be merged into a cascade mechanism model. Such detailed knowledge of toxic events is crucial for the effective use of cyanobacteria to remove the cadmium pollution from water.In conclusion, this thesis contributes to our

BACKGROUND: Black widow spider (L. tredecimguttatus) has toxic components not only in the venomous glands, but also in other parts of the body and its eggs. It is biologically important to investigate the molecular basis of the egg toxicity. RESULTS: In the present work, an aqueous extract was prepared from the eggs of the spider and characterized using multiple physiological and biochemical strategies. Gel electrophoresis and mass spectrometry demonstrated that the eggs are rich in high-molecular-mass proteins and the peptides below 5 kDa. The lyophilized extract of the eggs had a protein content of 34.22% and was shown to have a strong toxicity towards mammals and insects. When applied at a concentration of 0.25 mg/mL, the extract could completely block the neuromuscular transmission in mouse isolated phrenic nerve-hemidiaphragm preparations within 12.0 ± 1.5 min. Using whole-cell patch-clamp technique, the egg extract was demonstrated to be able to inhibit the voltage-activated Na+, K+and Ca2+ currents in rat DRG neurons. In addition, the extract displayed activities of multiple hydrolases. Finally, the molecular basis of the egg toxicity was discussed. CONCLUSIONS: The eggs of black widow spiders are rich in proteinous compounds particularly the high-molecular-mass proteins with different types of biological activity The neurotoxic and other active compounds in the eggs are believed to play important roles in the eggs' toxic actions.

This paper studies the echo-contrast properties of an alumina nanopowder suspension using ultrasonography (US) fully corresponding in its characteristics to the techniques of medical ultrasound diagnostics of organs and tissues. The purpose of this study was to search for the possible effect of the ionic and protein composition of the biological medium on the intensity of the reflected echo signal of the contrast material based on nanoparticles. It was found that the pH of the blood promotes the maximum use of echo contrast options of alumina nanopowder suspensions. Particle size measurements in the suspension using the dynamic light scattering technique showed the stabilizing effect of blood serum and plasma on the nanopowder suspension, resulting in the attenuation of the echo signal. The data offer a basis for the development of new contrast materials based on nanoparticles for the ultrasound imaging of the heart and blood vessels. The considered mechanisms of the established phenomena make it possible to elucidate the processes of interaction of metal oxide nanoparticles with biological molecules. © 2013 Pleiades Publishing, Ltd.

The quality of soybean [Glycine max (L.) Merr.] food products been associated with subunit composition of storage proteins. The objective of this study was to estimate protein composition of seed storage proteins, glycinin and β-conglycinin, among high-protein soybean genotypes. The trials were carried out at Experimental Fields of Institute of Field and Vegetable Crops in Novi Sad, Serbia during 2004 and 2005. The protein structure was estimated by scanning SDS-PAGE gels using densitometry. Our study confirmed observation that high-protein cultivars accumulated higher amount of both glycinin and β-conglycinin. Genotype KO5311 had the optimal protein composition and could be beneficial in breeding programs aimed at altering composition of seed storage proteins. The significant differences were observed among years for the protein content, α’ and β-subunits of β-conglycinin., Kvalitet proizvoda od soje zavisi od sadržaja proteinskih frakcija rezervnih proteina. Cilj ovog rada je utvrđivanje proteinske strukture visoko- proteinskih genotipova soje, kao i određivanje relativnog sadržaja glicininskih i β-konglicininskih subjedinica. Ogled je izveden na poljima Instituta za ratarstvo i povrtarstvo tokom 2004. i 2005. godine, a proteinska struktura određena je pomoću SDS PAGE i analizirana denzitometrijski. Dobijeni rezultati pokazuju da usled povećanja ukupnih proteina dolazi i do povećanja sadržaja proteinskih frakcija. Genotip KO5311 pokazao je najpovoljniju proteinsku strukturu i mogao bi imati značaj u oplemenjivanju soje na specifičan proteinski sastav. Uticaj godine na proteinske frakcije ustanovljen je samo kod α’ i β subjedinice β konglicinina i sadržaj ukupnih proteina.

The influence of limited proteolysis of soy protein concentrate on protein extractability, the composition of the extractable proteins, their emulsifying properties and some nutritional properties were investigated. Traditional concentrate (alcohol leached concentrate) was hydrolyzed using trypsin and pepsin as hydrolytic agents. Significant differences in extractable protein composition between traditional concentrate and their hydrolysates were observed by polyacrylamide gel electrophoresis (PAGE) and by SDS-PAGE. All hydrolysates showed better extractability than the original protein concentrate, whereas significantly better emulsifying properties were noticed at modified concentrates obtained by trypsin induced hydrolysis. These improved properties are the result of two simultaneous processes, dissociation and degradation of insoluble alcohol-induced protein aggregates. Enzyme induced hydrolysis had no influence on trypsin-inibitor activity, and significantly reduced phytic acid content.

The influence of limited proteolysis of soy protein concentrate on protein extractability, the composition of the extractable proteins, their emulsifying properties and some nutritional properties were investigated. Traditional concentrate (alcohol leached concentrate) was hydrolyzed using trypsin and pepsin as hydrolytic agents. Significant differences in extractable protein composition between traditional concentrate and their hydrolysates were observed by polyacrylamide gel electrophoresis (PAGE) and by SDS-PAGE. All hydrolysates showed better extractability than the original protein concentrate, whereas significantly better emulsifying properties were noticed at modified concentrates obtained by trypsin induced hydrolysis. These improved properties are the result of two simultaneous processes, dissociation and degradation of insoluble alcohol-induced protein aggregates. Enzyme induced hydrolysis had no influence on trypsin-inibitor activity, and significantly reduced phytic acid content.

A comparison of catabolic capacity was made between S. cerevisiae cells subjected to 24 h carbon or nitrogen starvation. The cells were shifted to starvation conditions at the onset of respiratory growth on ethanol in aerobic batch cultures, using glucose as the carbon and energy source. The results showed that the catabolic capacity was preserved to a much larger extent during carbon compared to nitrogen starvation. Nitrogen starvation experiments were made in the presence of ethanol (not glucose) to exclude the effect of glucose transport inactivation (Busturia and Lagunas, 1986). Hence, the difference in catabolic capacity could not be attributed to differences in glucose transport capacity during these conditions. In order to understand the reason for this difference in starvation response, measurement of protein composition, adenine nucleotides, inorganic phosphate, poly phosphate and storage carbohydrates were performed. No clear correlation between any of these variables and catabolic capacity after starvation could be obtained. However, there was a positive correlation between total catabolic activity and intracellular ATP concentration when glucose was added to starved cells. The possible mechanism for this correlation, as well as what determines the ATP level, is discussed.

Synaptonemal complexes (SCs) are ladderlike protein structures, which are formed between homologous chromosomes during the prophase of the first meiotic division. SCs consist of two axial elements, one along each chromosome, and transverse filaments (TFs), which connect the axial elements. On the TFs, between the axial elements, there is a third longitudinal structure, the central element (CE). Possible functions of the axial elements include organization of the chromatin in loops, providing sister chromatid cohesion, stabilization of chiasmata and regulation of recombination. These possible functions are explained in chapter 1 . In axial elements of SCs of rat, two major protein components have been identified, named SCP2 and SCP3, with relative electrophoretic mobilities ( Mr ) of 190,000 and 30,000-33,000. This study mainly focused on the analysis of the function of SCP2.In chapter 2 we describe how we isolated and sequenced the cDNA encoding SCP2 of the rat (rnSCP2). The protein predicted from the nucleotide sequence is basic and has a mass of 173 kDa. At the C-terminus, SCP2 contains a region, which is predicted to be capable of forming a coiled-coil structure. Furthermore, SCP2 contains two clusters of S/T-P motifs, which are common in DNA-binding proteins, and several potential phosphorylation sites. The SCP2 gene is expressed predominantly in meiotic prophase cells.In order to identify conserved domains within SCP2, we isolated and analyzed the human SCP2 cDNA (hsSCP2). This is described in chapter 3 . Although there is only 63% identity at the amino acid level between hsSCP2 and rnSCP2, several structural features and amino acid sequence motifs are conserved; hsSCP2 contains S/T-P motifs, which are commonly found in DNA-binding proteins, in the same domains as rnSCP2 and has a predicted coiled-coil region at its C-terminus. The structural organization of hsSCP2 and rnSCP2 resembles the structural organization of Red1, a protein component of the axial elemen

Using historic lactation records for Ayrshire cattle, we report a gradual increase in the production of milk, butter fat and protein levels across four decades. This was generally at the extent of attaining a level of increase per decade which was similar to the increase seen between animals during their first and second lactations in the previous decade. However these increases were achieved without significantly affecting the percentage of butter fat or protein throughout the time examined, and also without changing the heifer : second lactation ratios.

Using historic lactation records for Ayrshire cattle, we report a gradual increase in the production of milk, butter fat and protein levels across four decades. This was generally at the extent of attaining a level of increase per decade which was similar to the increase seen between animals during their first and second lactations in the previous decade. However these increases were achieved without significantly affecting the percentage of butter fat or protein throughout the time examined, and also without changing the heifer : second lactation ratios.