Lattice Enthalpies of Lanthanide Orthovanadates LnVO4

Lattice enthalpies ΔLH° of lanthanide orthovanadates, LnVO4 (Ln = Ce - Lu, except Pm) have been deter-mined from the Born-Haber thermochemical cycle and compared with those calculated by an empirical equation. Two different sets of enthalpies of formation of LnVO4, from oxides (Ln2O3, V2O5) and from elements, have been used but the differences in ΔLH° are small. The Born-Haber cycle in both routes yields close values of ΔLH° to those obtained after an empirical equation proposed by Glasser and Jenkins. It has been found that the partial derivative of the lattice enthalpies to the molar volumes corresponds by magnitude and dimension to the shear moduli of these crystals. (doi: 10.5562/cca2298

Regulation of the phosphotransferase system (PTS)-mediated sugar uptake in Corynebacterium glutamicum in response to perturbations of the central metabolism

Corynebacterium glutamicum is a Gram-positive bacterium used in the biotechnological production of amino acids. It co-metabolizes most substrates, such as glucose and sucrose. The uptake and concomitant phosphorylation of those two substrates is mediated by the phosphoenolpyruvate (PEP)-dependent phosphotransferase system (PTS), consisting of the common proteins HPr and EI, and an array of substrate-specific EII permeases. The PTS plays a central role in the regulation of nutrient uptake and metabolism in bacteria. However, the regulatory functions of the PTS in C. glutamicum are not understood. As the availability of NADPH is a limiting factor for the biosynthesis of amino acids, the deletion of pgi, encoding the enzyme phosphoglucoisomerase, is a promising approach for strain improvement. It blocks the first step of glycolysis and directs the glucose-derived carbon flux towards the NADPH-producing pentose phosphate pathway. However, despite that C. glutamicum Δpgi grows well with sucrose as a sole carbon source, addition of glucose arrests growth by causing repression of ptsS, encoding the sucrose-specific EIIsuc, and a drastic sucrose uptake inhibition. The regulatory mechanism behind these phenomena was unknown and has been investigated here. It was shown that the glucose addition inhibits sucrose uptake in C. glutamicum Δpgi prior to ptsS-repression and this fast process is not prevented by transcriptional or translational inhibitors. Analysis of the phosphorylation state of HPr - the last common component of the PTS phosphorylation cascade - indicated that the uptake inhibition is caused by a rapid depletion of HPr~P. The addition of non-PTS substrates which generate carbon flux towards glucose-6-P like e.g. maltose or glucose-6-P, uptake of which was enabled by the heterologously expressed transporter UhpT, led to similar growth and sucrose uptake inhibition as the addition of glucose. Unlike glucose, those substrates do not consume PEP for their uptake, so that the HP~P depletion is not caused by a decrease of the PEP/pyruvate ratio but by a glucose-6-P stress response mechanism. Perception of the glucose-6-P stress and the following response initiation requires the glucose-specific EIIglc as in EIIglc-deficient pgi mutants sucrose uptake was not inhibited by glucose, glucose-6-P or maltose addition. Further, it was shown that the low ptsS-mRNA levels observed in C. glutamicum Δpgi after glucose addition are a consequence of transcriptional repression by the regulator SugR. EMSA studies indicated fructose-1-P and to a lesser extent fructose-6-P as inhibitors of the SugR binding to the ptsS-promoter region. Taken together, this work shows that EIIglc is part of a novel mechanism for the perception of sugar-P stress which leads to instantaneous inhibition of the PTS phosphorylation cascade and consequently PTS activity in C. glutamicum. Additionally, this rapid uptake inhibition leads to low fructose-1-P formation and thus by an inducer exclusion mechanism, to SugR-dependent reduction of ptsS-expression. A suppressor mutation in the gene cg0790 (lpdA) was found to improve significantly the growth, sucrose uptake and ptsS-expression of C. glutamicum Δpgi during cultivation in the presence of glucose. The role of the novel regulatory mechanism for PTS regulation in C. glutamicum is also discussed

アンギオテンシンII ハ タンリ モルモット シンボウキン サイボウ ニ オイテ AT1 ジュヨウタイ シゲキ ヲ カイシテ カンジョ カッセイガタ チエン セイリュウセイ K+ デンリュウ ヲ ゾウダイサセル

学位授与機関：　滋賀医科大学　博士（医学）第534号　平成19年3月26日Circulation. 113(10), p.1278-1286

The influence of the exploatation of the gas CO2 and mineral water from vicinity "Popojci“ village Dolno Oriziari-Bitola on the living environment

The pollution of the underground water, concerning their easy injurance is the most important problem that the civilization is facing, present days. The protection of the surface and underground water, soil, the air is most important thing, which in the present civilization is left to be done and to release pure resources of clean drinking water for the next generations. Normally, every additional motive power on this space from Pelagonian basin should be expected to bring micro and macro changes of the living environment, which can arose multiple consequences first of all in the harmless of the underground water. It should be mentioned that every drop of dirt that falls on the surface of the soil will migrate in the depth of the soil. In this paper, gained results from the research and the quality of the mineral water and the gas CO2 are described, as well as the way of the exploitation of the mineral water and the influence of the exploitation on the living environment

An Algorithmic Approach to Inferring Cross-Ontology Links while Mapping Anatomical Ontologies

ACM Computing Classification System (1998): J.3.Automated and semi-automated mapping and the subsequently merging of two (or more) anatomical ontologies can be achieved by (at least) two direct procedures. The first concerns syntactic matching between the terms of the two ontologies; in this paper, we call this direct matching (DM). It relies on identities between the terms of the two input ontologies in order to establish cross-ontology links between them. The second involves consulting one or more external knowledge sources and utilizing the information available in them, thus providing additional information as to how terms (concepts) from the two input ontologies are related/linked to each other. Each of the two ontologies is aligned to an external knowledge source and links representing synonymy, is-a parent-child, and part-of parent-child relations, are drawn between the ontology and the knowledge source. These links are then run through a set of simple logical rules in order to come up with cross-ontology links between the two input ontologies. This method is known as semantic matching. It proves usefu

Opportunities and Challenges to Profile mRNA Modifications in Escherichia coli

mRNA methylation is an important regulator of many physiological processes in eukaryotes but has not been studied in depth in prokaryotes. Working with bacterial mRNA is challenging because it lacks a poly(A)-tail. However, methods for detecting RNA modifications, both sequencing and mass spectrometry, rely on efficient preparation of mRNA. Here, we compared size-dependent separation by electrophoresis and rRNA depletion for enrichment of Escherichia coli mRNA. The purification success was monitored by qRT-PCR and RNA sequencing. Neither method allowed complete removal of rRNA. Nevertheless, we were able to quantitatively analyze several modified nucleosides in the different RNA types. We found evidence for stress dependent RNA modification reprofiling in rRNA, but also several modified nucleosides in the mRNA enriched fractions showed significant changes

Accelerating Molecular Graph Neural Networks via Knowledge Distillation

Recent advances in graph neural networks (GNNs) have enabled more comprehensive modeling of molecules and molecular systems, thereby enhancing the precision of molecular property prediction and molecular simulations. Nonetheless, as the field has been progressing to bigger and more complex architectures, state-of-the-art GNNs have become largely prohibitive for many large-scale applications. In this paper, we explore the utility of knowledge distillation (KD) for accelerating molecular GNNs. To this end, we devise KD strategies that facilitate the distillation of hidden representations in directional and equivariant GNNs, and evaluate their performance on the regression task of energy and force prediction. We validate our protocols across different teacher-student configurations and datasets, and demonstrate that they can consistently boost the predictive accuracy of student models without any modifications to their architecture. Moreover, we conduct comprehensive optimization of various components of our framework, and investigate the potential of data augmentation to further enhance performance. All in all, we manage to close the gap in predictive accuracy between teacher and student models by as much as 96.7% and 62.5% for energy and force prediction respectively, while fully preserving the inference throughput of the more lightweight models.Comment: Accepted as a conference paper at NeurIPS 202

NAIL-MS reveals the repair of 2-methylthiocytidine by AlkB in E. coli

RNAs contain post-transcriptional modifications, which fulfill a variety of functions in translation, secondary structure stabilization and cellular stress survival. Here, 2-methylthiocytidine (ms(2)C) is identified in tRNA of E. coli and P. aeruginosa using NAIL-MS (nucleic acid isotope labeling coupled mass spectrometry) in combination with genetic screening experiments. ms(2)C is only found in 2-thiocytidine (s(2)C) containing tRNAs, namely tRNA(CCG)(Arg), tRNA(ICG)(Ar)(g), tRNA(UCU)(Arg) and tRNA(GCU)(Ser )at low abundances. ms(2)C is not formed by, commonly known tRNA methyltransferases. Instead, we observe its formation in vitro and in vivo during exposure to methylating agents. More than half of the s(2)C containing tRNA can be methylated to carry ms(2)C. With a pulse-chase NAIL-MS experiment, the repair mechanism by AlkB dependent sulfur demethylation is demonstrated in vivo. Overall, we describe ms(2)C as a bacterial tRNA modification and damage product. Its repair by AlkB and other pathways is demonstrated in vivo by our powerful NAIL-MS approach

Predicting and Scoring Links in Anatomical Ontology Mapping

The paper presents a work performed in the area of automatic and semi-automatic ontology mapping. A method for inferring additional cross-ontology links while mapping anatomical ontologies is described and the results of some experiments performed with various external knowledge sources and scoring schemes are discussed as well