Glyceraldehyde-3-phosphate dehydrogenase from Thermotoga maritima: Strategies of protein stabilization

Abstract: The molecular origin of protein stability has been the subject of active research for more than a generation (R. Jaenicke (1991) Eur. J. Biochem. 202, 715–728). Faced with the discovery of extremophiles, in recent years the problem has gained momentum, especially because of its biotechnological potential. In analyzing a number of enzymes from the hyperthermophilic bacterium Thermotoga maritima , it has become clear that the excess free energy of stabilization is equivalent to only a few weak bonds ( ΔΔG _stab≈ 50 kJ/mol). As taken from the comparison of homologous enzymes from mesophiles, thermophiles and hyperthermophiles, these accumulate from local interactions (especially ion pairs), enhanced secondary or supersecondary structure, and improved packing of domains and/or subunits, without significantly altering the overall topology. In this review, glyceraldehyde-3-phosphate dehydrogenase will be discussed as a representative example to illustrate possible adaptive strategies to the extreme thermal stress in hydrothermal vents.     

Identifying essential genes in bacterial metabolic networks with machine learning methods

Background  

Identifying essential genes in bacteria supports to identify potential drug targets and an understanding of minimal requirements for a synthetic cell. However, experimentally assaying the essentiality of their coding genes is resource intensive and not feasible for all bacterial organisms, in particular if they are infective.     

Accommodating scenarios of climate change and management in modelling the distribution of the invasive tree Schinus molle in South Africa

Determining the potential range of invasive alien species under current conditions is important. However, we also need to consider future distributions under scenarios of climate change and different management interventions when formulating effective long‐term intervention strategies. This paper combines niche modelling and fine‐scale process‐based modelling to define regions at high risk of invasion and simulate likely dynamics at the landscape scale. Our study species is Schinus molle (Peruvian pepper tree; Anacardiaceae), a native of central South America, introduced to South Africa in about 1850 where it was widely planted along roads. Localities of planted and naturalized trees were mapped along 5380 km of roads – a transect that effectively samples a large part of western South Africa. Correlative modelling was used to produce profiles of present and future environmental conditions characterizing its planted and naturalized ranges. A cellular‐automata simulation model was used to estimate the dynamics of S. molle under future climates and different management scenarios. The overall potential range of S. molle in the region is predicted to shrink progressively with predicted climate change. Some of the potential range of S. molle defined based on current conditions (including areas where it is currently highly invasive) is likely to become less favourable. The species could persist where it is well established long after conditions for recruitment have deteriorated. Some areas where the species is not widely naturalized now (notably the fynbos biome) are likely to become more favourable. Our modelling approach allows for the delineation of areas likely to be invaded in future by considering a range of factors at different scales that mediate the interplay of climatic variables and other drivers that define the dimensions of human intervention such as distance from planted trees and the density of planted plants, both of which affect propagule pressure.     

Biodegradation of alkali lignin by a newly isolated Rhodococcus pyridinivorans CCZU-B16

Bioprocess and Biosystems Engineering - Based on the Prussian blue spectrophotometric method, one high-throughput screening strategy for screening lignin-degrading microorganisms was built on...     

High-throughput system for determining dissolution kinetics of inclusion bodies

Efficient solubilization is a crucial step during inclusion body processing and dissolving conditions were usually empirically established. Here we describe a new methodology for rapid screening of solubilization conditions and evaluation of dissolution kinetics in microtiter plates. Increase of protein in solution over time was directly related to decrease of turbidity measured by absorbance at 600 nm. Dissolution kinetics of inclusion bodies were described by a first-order reaction kinetics, which was used for drug dissolution modeling. Reaction constants were in the range of 0.01–0.03 s^–1 for buffer conditions providing sufficient solubilization power. This method is not limited to the screening of optimal buffer conditions for solubilization and can be applied for studying other parameters involved in the solubility of IBs, such as pI of the protein, influence of fermentation conditions, influence of initial protein concentration, and more.     

The Culture-Transmission Motive in Immigrants: A World-Wide Internet Survey

A world-wide internet survey was conducted to test central assumptions of a recent theory of cultural transmission in minorities proposed by the authors. 844 1^st to 2^nd generation immigrants from a wide variety of countries recruited on a microjob platform completed a questionnaire designed to test eight hypotheses derived from the theory. Support was obtained for all hypotheses. In particular, evidence was obtained for the continued presence, in the immigrants, of the culture-transmission motive postulated by the theory: the desire to maintain the culture of origin and transmit it to the next generation. Support was also obtained for the hypothesized anchoring of the culture-transmission motive in more basic motives fulfilled by cultural groups, the relative intra- and intergenerational stability of the culture-transmission motive, and its motivating effects for action tendencies and desires that support cultural transmission under the difficult conditions of migration. Furthermore, the findings suggest that the assumption that people have a culture-transmission motive belongs to the folk psychology of sociocultural groups, and that immigrants regard the fulfillment of this desire as a moral right.