Heterogeneous popularity of metabolic reactions from evolution

The composition of cellular metabolism is different across species. Empirical data reveal that bacterial species contain similar numbers of metabolic reactions but that the cross-species popularity of reactions is so heterogenous that some reactions are found in all the species while others are in just few species, characterized by a power-law distribution with the exponent one. Introducing an evolutionary model concretizing the stochastic recruitment of chemical reactions into the metabolism of different species at different times and their inheritance to descendants, we demonstrate that the exponential growth of the number of species containing a reaction and the saturated recruitment rate of brand-new reactions lead to the empirically identified power-law popularity distribution. Furthermore, the structural characteristics of metabolic networks and the species' phylogeny in our simulations agree well with empirical observations.Comment: Main: 5 pages, 4 figures, Supplemental Material: 4 pages, 6 figure

A Study on the Effect of Manual Therapy on Physical Function Improvement in Middle-Aged Women with Lumbago

Most people experience lumbago at least once in their lifetime. In particular, it was found that lumbago prevalence was high in women experiencing pregnancy and childbirth. However, lumbago is difficult to be cured and has a high recurrence rate. This study, accordingly, investigated the effects of easily-accessible manual therapy on lumbago and physical function in middle-aged women. Subjects were randomly assigned to an experimental group to receive manual therapy and a control group to receive hyperthermia, and the Oswestry Disability Index (ODI) and joint range of motion were measured and analyzed. The results showed a positive effect on physical function improvement and back pain reduction in the experimental group to which manual therapy was applied, supporting that manual therapy is an alternative therapy that can help reduce lumbago and improve physical function in middle-aged women

Correlation-enhanced viable core in metabolic networks

Cellular ingredient concentrations can be stabilized by adjusting generation and consumption rates through multiple pathways. To explore the portion of cellular metabolism equipped with multiple pathways, we categorize individual metabolic reactions and compounds as viable or inviable: A compound is viable if processed by two or more reactions, and a reaction is viable if all of its substrates and products are viable. Using this classification, we identify the maximal subnetwork of viable nodes, referred to as the {\it viable core}, in bipartite metabolic networks across thousands of species. The obtained viable cores are remarkably larger than those in degree-preserving randomized networks, while their broad degree distributions commonly enable the viable cores to shrink gradually as reaction nodes are deleted. We demonstrate that the positive degree-degree correlations of the empirical networks may underlie the enlarged viable cores compared to the randomized networks. By investigating the relation between degree and cross-species frequency of metabolic compounds and reactions, we elucidate the evolutionary origin of the correlations.Comment: 8 pages, 4 figure

Optimizing pentose utilization in yeast: the need for novel tools and approaches

Hexose and pentose cofermentation is regarded as one of the chief obstacles impeding economical conversion of lignocellulosic biomass to biofuels. Over time, successful application of traditional metabolic engineering strategy has produced yeast strains capable of utilizing the pentose sugars (especially xylose and arabinose) as sole carbon sources, yet major difficulties still remain for engineering simultaneous, exogenous sugar metabolism. Beyond catabolic pathways, the focus must shift towards non-traditional aspects of cellular engineering such as host molecular transport capability, catabolite sensing and stress response mechanisms. This review highlights the need for an approach termed 'panmetabolic engineering', a new paradigm for integrating new carbon sources into host metabolic pathways. This approach will concurrently optimize the interdependent processes of transport and metabolism using novel combinatorial techniques and global cellular engineering. As a result, panmetabolic engineering is a whole pathway approach emphasizing better pathways, reduced glucose-induced repression and increased product tolerance. In this paper, recent publications are reviewed in light of this approach and their potential to expand metabolic engineering tools. Collectively, traditional approaches and panmetabolic engineering enable the reprogramming of extant biological complexity and incorporation of exogenous carbon catabolism

Symmetrical Aspects of Urban Regeneration in Seoul

Korea has developed very rapidly since 1980s highlighted with Seoul olympic, and urbanization necessarily incurred. Population grew with increasing housing demands, but old towns could not provide enough land. The old town was already congested, and living conditions fell off. Therefore, new towns outside the old town were planned and built through three sequential phases. This suburbanization brought about heavy load on commuter transportation and air pollution. At the same time, improper infrastructure and amenities turned new towns into bedtowns. To escape from bedtowns, people returned to the old town, and urban remodeling was needed to accommodate adequate living conditions. In doing so, local characteristics were lost. Urban regeneration aroused as a countermeasure to this mishap. In this study, urban regeneration reinforced with smart technologies is suggested to revive lost placeness, communal connectivity, and urban orientation. Gentrification is another important issue to be resolved for the sustainable urbanization. This study focused on symmetrical aspects of the successful urban regeneration

Engineered xylose transporters with reduced glucose inhibition

Provided herein are compositions and methods useful for reducing glucose inhibition in transporting xylose, arabinose and other monosaccharides, into a yeast cell.Board of Regents, University of Texas Syste