Presence Of Forms Research Articles

Sodium-induced population shift drives activation of thrombin

The equilibrium between active E and inactive E* forms of thrombin is assumed to be governed by the allosteric binding of a Na+ ion. Here we use molecular dynamics simulations and Markov state models to sample transitions between active and inactive states. With these calculations we are able to compare thermodynamic and kinetic properties depending on the presence of Na+. For the first time, we directly observe sodium-induced conformational changes in long-timescale computer simulations. Thereby, we are able to explain the resulting change in activity. We observe a stabilization of the active form in presence of Na+ and a shift towards the inactive form in Na+-free simulations. We identify key structural features to quantify and monitor this conformational shift. These include the accessibility of the S1 pocket and the reorientation of W215, of R221a and of the Na+ loop. The structural characteristics exhibit dynamics at various timescales: Conformational changes in the Na+ binding loop constitute the slowest observed movement. Depending on its orientation, it induces conformational shifts in the nearby substrate binding site. Only after this shift, residue W215 is able to move freely, allowing thrombin to adopt a binding-competent conformation.

Recent Evaluation of Corbicula Form D Distribution in the Midwest, U.S.A.

The genus Corbicula contains one of the most common and successful aquatic invasive species to North America. Prior to 2015 two predominant species of Corbicula were known from the United States—C. fluminea and C. largillierti, referred to as Forms A and B, respectively. Form A has spread throughout most of the U.S., while Form B is mainly contained in the Midwest and southern U.S. In 2015 a novel Corbicula, known as Form D, was discovered in the Illinois River, at Marseilles, Illinois, and was later reported from the Ohio River. Our primary objective for this study was to report additional records of Form D, with a focus on the upper Illinois River watershed. Surveys during summer 2017 verified the presence of Form D in the Tennessee and Mississippi rivers, as well as multiple new locations in the Des Plaines and Illinois rivers, where all three Corbicula forms co-exist.

All-solid-state polymeric screen printed and carbon paste ion selective electrodes for determination of oxymetazoline in pharmaceutical dosage forms

All-solid state potentiometric ion selective electrodes have the merits of being portable, small and suitable for small volume samples. Herein, disposable home-made screen printed polymeric ion selective electrode (SPE) is developed for determination of oxymetazoline (OXM) in pharmaceutical nasal drops and drug substance. Ion selective electrodes with optimal potentiometric response were achieved by careful selection of the ion exchanger and plasticizer. A screen printed electrode utilizing oxymetazoline-tetraphenyl borate (OXM-TPB) as an ion exchanger and dibutyl phthalate (DBP) as a plasticizer exhibited a Nernstian slope of 59.5±0.5 mV/decade (n=3) over the concentration range from 1×10-5 to 1×10-2 M OXM (r = 0.9999) with a detection limit of 5.0×10-6 M. The electrode is useful over a wide pH range from 4.0 to 8.0. The electrode showed a high selectivity for OXM against several common interfering ions. The potential interference from benzalkonium chloride was easily eliminated by treatment the sample with KI. Comparable potentiometric characteristics including linearity, detection limit, pH range and selectivity pattern were obtained with a carbon paste electrode (CPE) comprising same ion exchanger and plasticizer. The electrodes were successfully used for the assay of OXM in the drug substance and in the dosage form in presence of benzalkonium chloride with high accuracy (±2%) and precision (%RSD ˂2.5). The proposed method is simple, accurate and precise.

Dioxins and furans’ behavior in the process of zinc and lead removing from EAF dust

The use of galvanized scrap as a charge material for electric steel-smelting production leads to formation of metallurgical dust suitable for extraction of non-ferrous metals. Chlorine and organic compounds content in metallurgical charge can lead to dioxins and furans formation in the process of electric smelting with their subsequent sedimentation on EAF dust. In the previous study we determined dioxins and furans content in dust at the level of 474 ng/kg of EAF dust. The methodology for conducting an experiment in a muffle furnace at temperatures of 300, 600, 900 and 1150 °Cwas developed for the study of dioxins and furans’ behavior during dust heating. Investigation of EAF dust chemical composition before and after the experiment made it possible to establish that desorption of dioxins and furans occurs during heating in the temperature range of 300 – 900 °C. In parallel with dioxins and furans’ desorption some chemical compounds evaporate indirectly and it is determined by calculation of changes in the content of C, Na, Cl, K, Pb, Zn in the sample. In the studied temperature range, the content of C, Na, Cl decreases to zero; K content is reduced by 81 %; Pb content is reduced by 83.5 %. Reduction of Zn content does not exceed 5 %. Change in content of the remaining components is insignificant. The obtained data confirm the predominant presence of chlorine in inorganic compounds in forms of NaCl and KCl, along with a slight presence in forms of ZnCl, PbCl, and PbCl2 . The study revealed the need of consideration of dioxins and furans’ presence during development of technologies aimed at metallurgical dust processing. It is proposed to perform high-temperature processing of dust (>850 °С) with the subsequent irrigation of exhaust gases with lime milk. The most rational ways to decrease dioxins and furans’ content in EAF dust are conducting afterburning of exhaust gases, followed by rapid cooling in order to avoid secondary synthesis of ecotoxicants or reducing the amount of chlorine-containing and conventional materials during pretreatment of metals.

The virtual body of Christ and embrace of the seriously ill

ABSTRACT Since the time of the Apostle Paul, the body of Christ has always been a virtual body, made up of members who were not always physically present to one another but were nevertheless part of the same catholic community. Virtual presence in today’s society comes most often via digital technology, a reality that prompts many Christian leaders and theologians to warn of the dangers of disembodied existence. This paper challenges the claim that virtual presence via digital technology is necessarily an inferior form of presence. Using autoethnographic research of living with advanced-stage cancer, the author explores how virtual connection via technology can sometimes be a superior form of presence for those undone by illness and other traumas. The article concludes with a call to churches to draw on biblical, theological, and liturgical resources to help imagine how digital devices can be used to practice healing forms of attentiveness to those who need it most.

Multiplex PCR Method of Detecting Pork to Guarantee Halal Status in Meat Processed Products

One of the halal parameters of food is must be free from pork among from the basic ingredients, additives and the manufacturing process. The aim of this study was ensure the halal status in the form of presence or absence of pork in processed meat product (meatballs and sausages) in traditional markets in Pandeglang Regency. PCR multiplex was a PCR technique that used several primers together in one reaction to amplify several target sequence. The genes often used as markers of animal or meat types include cytochrome b (cyt b), the existence of sequence variations in cyt b causes these genes are widely used as markers to distinguish material from different types of animals. The results showed that the cyt b gene proved successful in amplified DNA from beef and pork with different fragment lengths in the DNA mix of the 2 types of livestock in one reaction so that 2 DNA bands formed with different lengths according to the length of the fragment from each animal. From the results of research showed beef and pork control there was two fragments such as 274 bp for beef and 389 bp for pork. Multiplex PCR testing on meatball samples showed that the meatballs were tested 100% positive containing beef and 0% containing pork DNA. While testing on sausage products, there were one sausage brand that showed the results of DNA amplification of 398pb, which means the product was positive containing pork.

Horn, Sahel and Rift: fault-lines of the African jihad

Stig Jarle Hansen brings years of experience, including field research in the Congo, Egypt, Kenya, Mali, Nigeria, Somalia, Tanzania and Uganda, to bear on a thought-provoking analysis of jihadist organizations in Africa. He argues that these organizations seldom disappear; instead, when faced with adversity, they transform themselves, substituting one form of territorial presence for another. The type of territorial presence varies from one African jihadist organization to another, and it also varies over the history of any one organization. Understanding these differences is central to viewing jihadist groups in Africa as dynamic bodies, experiencing immense changes. To make the point, Hansen develops a four fold typology of territorial presence for the jihadist groups analysed here. The clandestine network is the most commonly studied form of jihadist organization. It generally consists of small, cell-based structures and is normally the entry-level form of territorial presence. In the second scenario, known as accepted presence, the state hosts a jihadist organization in its territory, often manipulating it for its own purposes. In this form of presence, the jihadists may participate in violent acts outside the core areas of the state, but not within the confines of the state itself. In the third scenario, semi-territorial presence, the jihadist group exercises some level of control over part of the state, such as rural areas where the state and international forces are unable to provide security. ‘Semi-territoriality illustrates how these jihadist organizations do not need full control of a territory to implement rudimentary forms of governance, contrary to the conclusions of many scholars analysing rebel governance’ (p. 28). In the fourth and final scenario, territorial control, the jihadists have been able to establish stable control over an area for some time and have begun to build more permanent, public institutions of governance.

Mutational and structural studies uncover crucial amino acids determining activity and stability of 17β-HSD14

17β-Hydroxysteroid dehydrogenase type 14 (17β-HSD14) catalyzes the conversion of highly active estrogens and androgens into their less active oxidized forms in presence of NAD+ as cofactor. The crystal structure of 17β-HSD14 has been determined, however, the role of individual amino acids likely involved in the enzymatic function remains poorly understood. Objective of this study was to further characterize the enzyme by site-directed mutagenesis considering five amino acids next to the catalytic center. The tools used for the characterization of the enzyme variants are X-ray crystallography and enzyme kinetics. Lys158 was confirmed to belong to the catalytic triad. Tyr253′, located on the C-terminal loop of the adjacent monomer, enters into the active site of the neighboring monomer and interacts with the catalytic Tyr154. Therefore, Tyr253′ helps to tie the two monomers together. Cys255, located at the interface between both monomers, can form a disulfide bridge with the Cys255′ from the adjacent monomer. In contrast to the contact provided by Tyr253, the latter interaction is not crucial for dimer formation. His93 and Gln148 are located at the rim of the substrate binding pocket. His93 does not interact directly with the ligand in the active site. However, it influences the turnover of the enzyme. The Gln148 restricts in size the access tunnel of the substrate to the binding pocket.

Does “Being There” Matter? The Impact of Web-Based and Virtual World’s Shopping Experiences on Consumer Purchase Attitudes

The use of virtual worlds as an emerging technology is already having a significant impact on business to consumer commerce and on corporate Internet retailing strategies. This research investigates consumer behavior in e-commerce retail environments, particularly with respect to consumer attitudes toward using virtual world’s shopping compared to web-based, online shopping for real-world items. We investigate two forms of presence, perceived social presence and telepresence, and their effect on attitudes toward e-commerce, attitudes that ultimately influence the consumer's intention to shop using a particular e-commerce environment. Key implications of this research for researchers and practitioners are discussed.

BERENTAK DALAM RITUAL BESALE SUKU BATIN SEMBILAN KABUPATEN BATANGHARI, PROVINSI JAMBI, (KAJIAN ANALISIS TEKS DAN KONTEKS)

This research aimed to analyze the existence of a ritual besale typical movement, movement in the besale ritual process is berentak. Berentak motion is a movement running straight forward, backward, around and jumping, the movement continues to be done by Malin Pengasu (shaman) during the process of ritual besale. Besale is from of a magical traditional ceremony, which lives in remote indigenous communities of Suku Batin Sembilan, precisely in Jambi Province forest area. Besale (berasale) means the origin of man, ritual besale involves Malin Pengasu (shaman) and Sidi (good spirits who treat the sick through shaman), to cleanse and cast out the evil spirits that are considered as the source of the disease. Malin Pengasu (shaman) is a person who set all forms of preparation of beterkas up to the ritual besale. The research using the method of qualitative approach text and the context of according Y. Sumandiyo Hadi, which analyze and review the form, techniques, and style the choreography, and analyze the context of based social culture community. The results of research show about how the process of choreography and the emergence of distinctive motion in ritual besale, which in principle socio-cultural society that has been behind the presence of form, technique and style of motion.

TRANSITION ECONOMIES PROBLEMS WITH SPECIFIC FOCUS ON DEALING WITH SCALE OF CORRUPTION CASE STUDY – KOSOVO

Theoretical and empirical debate on the impact of corruption on the economy remains unclear. Many studies on corruption seem that the world is occupied by two kinds of people, "sanders" and "greasers”. It depends on what the meaning of "corruption" is for them. Some scholars argue that corruption is an obstacle to economic growth, whereas others believe that corruption can (in some circumstances) endorse growth. Corruption also has a negative impact on investment, Foreign Direct Investment, and economic development as a whole. Measuring corruption is still an issue for most economists due to the difficulties of defining it, and also different forms of corruption require different objective measures. Nevertheless, recently, some measures of corruption have been widely accepted and recognized by researchers. This paper is a critical review at these positions by reviewing the theoretical literature on the impact of corruption on an economy as a whole. In this paper we will treat the corruption level in Kosovo, and its presence in forms and ways how the bribe is been given. Instead, this document reviews different measurements of corruption to reveal that corruption is harmful for the economy.

A representação linguístico-discursiva de Jesus Cristo em seu sermão sobre o cumprimento do amor a partir do Evangelho segundo São Mateus

Este trabalho delimita como objeto de estudo “a representação linguístico-discursiva do sujeito enunciativo Jesus Cristo em seu sermão sobre o cumprimento do amor, a partir dos registros evangelísticos de São Mateus”. Os pontos de vista desse autor conferenciam responsividade diante dos acontecimentos registrados. Remetemo-nos a Bakhtin e o círculo para fundamentar nossa pesquisa, uma vez que a remissão ao campo da religião e ao universo cristão, com suas particularidades e símbolos, são recorrentes na produção dos estudiosos russos. O dado constitui-se de 5 (cinco) versículos bíblicos relatados por São Mateus sobre as palavras de Jesus. A exposição oral (sermão expositivo) geralmente se realiza numa situação de comunicação específica em que o orador (ou expositor) une-se, pela interação verbal, ao(s) seu(s) destinatário(s). Dessa forma, a exposição oral se caracteriza pelas diferentes formas de presença do outro, ou seja, presença de diversas vozes sociais resultantes de interações interdiscursivas. Trata-se, portanto, a pesquisa, de uma produção de cunho qualitativo-interpretativo. A versão bíblica que se adotou como suporte e referência para a composição deste trabalho foi a Bíblia de Jerusalém (Nova Edição Revista e Ampliada), cuja tradução foi realizada direto dos textos originais (hebraico e grego).

Molecular dynamics characterization of the SAMHD1 Aicardi–Goutières Arg145Gln mutant: structural determinants for the impaired tetramerization

Aicardi-Goutières syndrome, a rare genetic disorder characterized by calcification of basal ganglia, results in psychomotor delays and epilepsy states from the early months of children life. This disease is caused by mutations in seven different genes encoding proteins implicated in the metabolism of nucleic acids, including SAMHD1. Twenty SAMHD1 gene variants have been discovered and in this work, a structural characterization of the SAMHD1 Aicardi-Goutières Arg145Gln mutant is reported by classical molecular dynamics simulation. Four simulations have been carried out and compared. Two concerning the wild-type SAMHD1 form in presence and absence of cofactors, in order to explain the role of cofactors in the SAMHD1 assembly/disassembly process and, two concerning the Arg145Gln mutant, also in presence and absence of cofactors, in order to have an accurate comparison with the corresponding native forms. Results show the importance of native residue Arg145 in maintaining the tetramer, interacting with GTP cofactor inside allosteric sites. Replacement of arginine in glutamine gives rise to a loosening of GTP-protein interactions, when cofactors are present in allosteric sites, whilst in absence of cofactors, the occurrence of intra and inter-chain interactions is observed in the mutant, not seen in the native enzyme, making energetically unfavourable the tetramerization process.

SIMULTANEOUS DETERMINATION OF METFORMIN, LINAGLIPTIN IN JENTADUETO AND METFORMIN, SAXAGLIPTIN IN KOMBIGLYZE BY LC-MS METHOD

Objective: The objective of the present investigation was to develop a novel, simple and economic method for the determination of metformin (MET), linagliptin (LIN) and saxagliptin (SAX) in jentadueto and kombiglyze sample by employing the liquid chromatography and mass spectrometric method for estimation in bulk and pharmaceutical dosage form in presence of degradation products.Methods: The chromatographic separation was achieved by using the mobile phase composition of methanol and ammonium acetate buffer pH 4.5 (85:15 % v/v) on the Hypurity advance C-18 column at a flow rate of 0.5 ml/min. Ion signals m/z “130.10/70.10, 473.10/420.40 and 316.30/180.20” for metformin, linagliptin and saxagliptin respectively measured in positive ion mode. The detailed validation of the method was performed as per ICH guidelines.Results: The results of all validation parameters found within acceptance limits. The linearity of the drugs was found to be in the concentration range of 50–5000 ng/ml for all the drugs. Accuracy of the drugs was found to be from 94-102% and precision was found 4.67% RSD for all three drugs. The validated method was employed for the determination of drugs in the formulation and also determined the drugs in the presence of degradation products under stress conditions.Conclusion: The method was developed and validated as per guidelines. Hence, this method can be used for the simultaneous determination of metformin, linagliptin and metformin, saxagliptin in bulk and combined dosage forms.

DEVELOPMENT AND VALIDATION OF HPLC METHOD FOR THE SIMULTANEOUS DETERMINATION OF ENALAPRIL MALEATE IN PRESENT OF THEIR IMPURITIES: APPLICATION TO TABLET ANALYSIS

Objective: A simple, rapid, economical, and highly sensitive stability-indicating HPLC method was developed and fully validated for determination of enalapril maleate in presence of its related substances namely enalaprilat dihydrate and diketopiperazine.Methods: Chromatographic separation was achieved on Grace Platinumр C8 EPS column (4.6 mm i.d. X 250 mm, 5 μm) at room temperature. The mobile phase consisted of acetonitrile: 20 mmol phosphate buffer adjusted to pH 2.2 (25:75 v/v) isocratically pumped at a flow rate 2 ml/min and UV-detection was monitored at 215 nm.Results: The proposed method was validated according to ICH guidelines with total run time less than 9 min. The correlation coefficient (r2) was noted as 0.99981 which states that the method was good linear to the concentration versus peak area responses. The developed method found to be high sensitivity with LOD and LOQ of 0.021 and 0.062 %; respectively. The developed, validated method was successfully applied for the determination of enalapril maleate in presence of their impurities in tablet dosage form.Conclusion: A rapid, economical, simple and sensitive HPLC method was developed and validated for the determination of enalapril maleate in tablet dosage form in presence of their impurities. The developed method can help research studies, quality control and routine analysis with lesser resources available. Therefore, the proposed validated method is fast and reliable and can be used for routine quantitative analysis as well as quality control of enalapril maleate in pharmaceutical formulation.

Wkład Marie-Dominique Chenu i Paula Ricœura w odnowę nauki społecznej Kościoła w okresie wczesnej recepcji Soboru Watykańskiego II

The subject of the article is to show the contribution of the two thinkers of the time of the Second Vatican Council Marie-Dominique Chenu and Paul Ricœur in the debate concerning the methodological status and tasks of the social doctrine of the Church. The period of direct reception of Vatican II is seen as a time of disclosure to the crisis of the social doctrine of the Church and its setbacks. Presentation of the contribution of the above researchers of the social doctrine of the Church will be made on the background of the process of the development of new forms of presence and the relationship of the Church to the modern world.

Arsenite and arsenate immobilization by preformed and concurrently formed disordered mackinawite (FeS)

Arsenic (As) immobilization in aqueous environments is controlled by sorption and/or coprecipitation with iron (Fe) oxyhydroxides under oxic conditions and with ferrous iron (Fe(II)) and sulfide (S(-II)) minerals under anoxic conditions. Shifts to reducing conditions trigger the release of dissolved As by reductive dissolution of Fe oxyhydroxides. More stringent reducing conditions in sulfur (S) rich environments form solid S(-II) phases that immobilize As. This work studied the association of arsenite and arsenate with freshly-formed disordered mackinawite (FeS), a model Fe and reduced S mineral of environmental relevance. The association of As to preformed FeS (Set P experiments) was contrasted to the case when As is present during FeS precipitation (Set C experiments). Most abiotic studies of As reactivity under reducing conditions have been done under Set P setting, despite that redox shifts are likely to induce environments analogous to Set C experiments. Dissolved As removal was initially higher for Set C compared to Set P experiments at least by a factor of two, except for arsenate with low initial redox potential. Set C experiments had a rapid initial As sorption, followed by some As desorption. When stringent reducing conditions ensue, the extent and rate of As removal by FeS is misrepresented by sorption experiments to preformed FeS. A continuous release of As concurrent with the formation of thioarsenates - a dissolved form of As with weaker binding to Fe minerals - was observed in Set C experiments with arsenite. The formation of thioarsenates occurred preferably in Set C experiments at low redox potential, while it was negligible for arsenate experiments. Remarkably, the occurrence of thioarsenates disputes a widespread notion that their formation is inhibited by Fe(II)-S(-II) affinity and precipitation as FeS. This study shows the potential of FeS to scavenge arsenite and to decrease its mobility in reduced sediments and groundwater, and highlights the role of thioarsenates in As mobility in systems with changing redox conditions where the reactive solid forms in presence of the contaminant.

In the Eye of the Storm: Photographs of Russian Prisoners of War in Denmark during the First World War

ABSTRACTIn 1915 prisoners of war escaped to neutral Denmark from German camps. In 1917, in order to support its politics of neutrality, Denmark opened two POW camps where soldiers from the warring countries were nursed. The proliferation of images in Danish archives shows that the prisoners were photographed frequently. Portraits and group photographs were carried by soldiers, sent home and left with new acquaintances establishing new forms of presence in a landscape of distance and loss. Furthermore, the development of documentary photography and mass media brought the images of prisoners into the historical records of Denmark’s neutrality. In this context the collection of the young academic Ingeborg Stemann plays a key part. While working as an aid worker and as an interpreter in the POW camps she collected photographs and written records in order to document the experiences of Russian POWs. Taking her collection as a starting point this article conducts an analysis of photography as a means to strengthen identity and community across time and place. Along with other photographs from the period, it also tells the story of conflicts and tensions in a period of war and revolution as well as in the act of taking photographs itself.

Microwave-assisted synthesis of mixed ligands organotin(IV) complexes of 1,10-phenanthroline and l-proline: Physicochemical characterization, DFT calculations, chemotherapeutic potential validation by in vitro DNA binding and nuclease activity

Diorganotin(IV) and triphenyltin(IV) derivatives of L-proline (HPro) having general formula R2Sn(Pro)2 (R=n-Bu (1), Ph (2)) and Ph3Sn(Pro) (3), respectively, and the mixed ligands di-/triorganotin(IV) derivatives of L-proline and 1,10-phenanthroline (phen) with general formula [R2Sn(Pro)(Phen)Cl] and [R3Sn(Pro)(Phen)] (where R=Me (4 and 7), n-Bu (5 and 8), Ph (6 and 9)), respectively, have been synthesized by microwave-assisted method and characterized by elemental analysis, IR, NMR (1H, 13C and 119Sn) and DART-mass spectral studies. The results suggest bicapped tetrahedron or a skew trapezoidal-bipyramid geometry for R2Sn(Pro)2, a distorted tetrahedral geometry for Ph3Sn(Pro) and a distorted octahedral geometry for [R2Sn(Pro)(Phen)Cl] and [Ph3Sn(Pro)(Phen)] around the Sn atom, and the same has been validated by density functional theory calculations (DFT). In vitro DNA binding studies of 1–9 have been investigated by UV–Vis, fluorescence and circular dichroism titrations, viscosity and DNA melting experiments. The observed hypochromic shift in UV–Vis and fluorescence studies evidenced a partial intercalative mode of binding of complexes to CT-DNA. The binding affinity and quenching ability have been quantified in terms of intrinsic binding constant (Kb) and Stern-Volmer quenching constant (Ksv). The determined values suggest that di- and triorganotin(IV) derivatives of L-proline possess lesser affinity to bind with CT-DNA in comparison to the mixed ligands di-/triorganotin(IV) derivatives of L-proline and 1,10-phenanthroline. The partial intercalative mode of binding of these complexes with CT DNA has also been supported by a change in the viscosity and melting point of DNA as well as a change in the intensity of positive and negative bands in circular dichroism spectra. The cleavage studies by agarose gel electrophoresis indicate effective cleavage of supercoiled plasmid DNA into its nicked form by all the complexes and even to its linear form in presence of 9.

Biochemical characterization of Arabidopsis thaliana starch branching enzyme 2.2 reveals an enzymatic positive cooperativity

Starch Branching Enzymes (SBE) catalyze the formation of α(1 → 6) branching points on starch polymers: amylopectin and amylose. SBEs are classified in two groups named type 1 and 2. Both types are present in the entire plant kingdom except in some species such as Arabidopsis thaliana that expresses two type 2 SBEs: BE2.1 and BE2.2. The present work describes in vitro enzymatic characterization of the recombinant BE2.2.The function of recombinant BE2.2 was characterized in vitro using spectrophotometry assay, native PAGE and HPAEC-PAD analysis. Size Exclusion Chromatography separation and SAXS experiments were used to identify the oligomeric state and for structural analysis of this enzyme.Optimal pH and temperature for BE2.2 activity were determined to be pH 7 and 25 °C. A glucosyl donor of at least 12 residues is required for BE2.2 activity. The reaction results in the transfer in an α(1 → 6) position of a glucan preferentially composed of 6 glucosyl units. In addition, BE2.2, which has been shown to be monomeric in absence of substrate, is able to adopt different active forms in presence of branched substrates, which affect the kinetic parameters.BE2.2 has substrate specificity similar to those of the other type-2 BEs. We propose that the different conformations of the enzyme displaying more or less affinity toward its substrates would explain the adjustment of the kinetic data to the Hill equation.This work describes the enzymatic parameters of Arabidopsis BE2.2. It reveals for the first time conformational changes for a branching enzyme, leading to a positive cooperative binding process of this enzyme.