The deep-subsurface sulfate reducer Desulfotomaculum kuznetsovii employs two methanol-degrading pathways

Methanol is generally metabolized through a pathway initiated by a cobalamine-containing methanol methyltransferase by anaerobic methylotrophs (such as methanogens and acetogens), or through oxidation to formaldehyde using a methanol dehydrogenase by aerobes. Methanol is an important substrate in deep-subsurface environments, where thermophilic sulfate-reducing bacteria of the genus Desulfotomaculum have key roles. Here, we study the methanol metabolism of Desulfotomaculum kuznetsovii strain 17T, isolated from a 3000-m deep geothermal water reservoir. We use proteomics to analyze cells grown with methanol and sulfate in the presence and absence of cobalt and vitamin B12. The results indicate the presence of two methanol-degrading pathways in D. kuznetsovii, a cobalt-dependent methanol methyltransferase and a cobalt-independent methanol dehydrogenase, which is further confirmed by stable isotope fractionation. This is the first report of a microorganism utilizing two distinct methanol conversion pathways. We hypothesize that this gives D. kuznetsovii a competitive advantage in its natural environment.Research was funded by grants of the Division of Chemical Sciences (CW-TOP 700.55.343) and Earth and Life Sciences (ALW 819.02.014) of The Netherlands Organisation for Scientific Research (NWO), the European Research Council (ERC grant 323009), and the Gravitation grant (024.002.002) of the Netherlands Ministry of Education, Culture and Scienceinfo:eu-repo/semantics/publishedVersio

The Cobalamin-Binding Protein in Zebrafish Is an Intermediate between the Three Cobalamin-Binding Proteins in Human

In humans, three soluble extracellular cobalamin-binding proteins; transcobalamin (TC), intrinsic factor (IF), and haptocorrin (HC), are involved in the uptake and transport of cobalamin. In this study, we investigate a cobalamin-binding protein from zebrafish (Danio rerio) and summarize current knowledge concerning the phylogenetic evolution of kindred proteins. We identified a cobalamin binding capacity in zebrafish protein extracts (8.2 pmol/fish) and ambient water (13.5 pmol/fish) associated with a single protein. The protein showed resistance toward degradation by trypsin and chymotrypsin (like human IF, but unlike human HC and TC). The cobalamin analogue, cobinamide, bound weaker to the zebrafish cobalamin binder than to human HC, but stronger than to human TC and IF. Affinity for another analogue, adenosyl-pseudo-cobalamin was low compared with human HC and TC, but high compared with human IF. The absorbance spectrum of the purified protein in complex with hydroxo-cobalamin resembled those of human HC and IF, but not TC. We searched available databases to further explore the phylogenies of the three cobalamin-binding proteins in higher vertebrates. Apparently, TC-like proteins are the oldest evolutionary derivatives followed by IF and HC (the latter being present only in reptiles and most but not all mammals). Our findings suggest that the only cobalamin-binding protein in zebrafish is an intermediate between the three human cobalamin binders. These findings support the hypothesis about a common ancestral gene for all cobalamin-binding proteins in higher vertebrates

Comparison of Recombinant Human Haptocorrin Expressed in Human Embryonic Kidney Cells and Native Haptocorrin

Haptocorrin (HC) is a circulating corrinoid binding protein with unclear function. In contrast to transcobalamin, the other transport protein in blood, HC is heavily glycosylated and binds a variety of cobalamin (Cbl) analogues. HC is present not only in blood but also in various secretions like milk, tears and saliva. No recombinant form of HC has been described so far. We report the expression of recombinant human HC (rhHC) in human embryonic kidney cells. We purified the protein with a yield of 6 mg (90 nmol) per litre of cell culture supernatant. The isolated rhHC behaved as native HC concerning its spectral properties and ability to recognize both Cbl and its baseless analogue cobinamide. Similar to native HC isolated from blood, rhHC bound to the asialoglycoprotein receptor only after removal of terminal sialic acid residues by treatment with neuraminidase. Interestingly, rhHC, that compared to native HC contains four excessive amino acids (…LVPR) at the C-terminus, showed subtle changes in the binding kinetics of Cbl, cobinamide and the fluorescent Cbl conjugate CBC. The recombinant protein has properties very similar to native HC and although showing slightly different ligand binding kinetics, rhHC is valuable for further biochemical and structural studies

Sport, War and Democracy in Classical Athens

This article concerns the paradox of athletics in classical Athens. Democracy may have opened up politics to every class of Athenian but it had little impact on sporting participation. The city’s athletes continued to drawn predominantly from the upper class. It comes as a surprise then that lower-class Athenians actually esteemed athletes above every other group in the public eye, honoured them very generously when they won, and directed a great deal of public and private money to sporting competitions and facilities. In addition athletics escaped the otherwise persistent criticism of upper-class activities in the popular culture of the democracy. The research of social scientists on sport and aggression suggests this paradox may have been due to the cultural overlap between athletics and war under the Athenian democracy. The article concludes that the practical and ideological democratization of war by classical Athens legitimized and supported upper-class sport

Using computer simulation to aid the research of drilling processes

Drilling wells is one of the primary methods used for mineral exploration. Scientific studies have aimed at improving the technical and economic aspects of drilling because of the current competitive economic conditions. Note that the primary topic of these studies has been developing new effective rock-cutting tools. To design a new rock-cutting tool, a thorough, reliable, and accurate study of the processes that occur during drilling is necessary. During drilling, mechanical, hydraulic, thermal, and chemical phenomena, which are interdependent and affect the performance of a drilling tool, simultaneously occur; therefore, a systematic, integrated approach is required for studying drilling processes. Field-based and laboratory experiments are quite tedious to perform and require high material costs, and it is often not possible to separately evaluate small elements of the drilling model. Therefore, computer simulation is an important research tool that enables accurate and reliable visualization of even small parts of the model. The aim. The aim of this study is to examine the potential for computer simulation of the processes that occur during drilling. Objective. In this study, we evaluated the simulation features of various software products, such as KOMPAS-3D, ANSYS, Delphi, and LabVIEW, for their utility in studying the processes that occur during drilling. The possibility of computer simulation for studying drilling processes, including its advantages and disadvantages, are demonstrated. The results are obtained from a model that simulates a rock cutting tool. The main uses of the rock cutting tool are outlined, and the drilling simulation development is planned. Choice of research method. The study of the capabilities of existing modern software products, for use in drilling process research, is carried out by an analytical review method

# 78 Methods to Support Co-operative Product Development

Abstract World-wide distributed product development processes and manufacturer supplier co-operation has become more important in recent years. This requires support for collaboration on the one hand and the administration of the generated data on the other hand. In this paper methods for determination of co-operation needs during distributed product development processes are presented. The particular cooperation situation which shall be supported can be classified by given criteria. New data management methods to support a distributed co-operation process are shown. A mapping scheme is provided that allows to assign these new data management methods to the classified co-operation needs