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Strong Driving Force (strong + driving_force)

Distribution by Scientific Domains

Chemistry	50%

Selected Abstracts

Glycosomes: parasites and the divergence of peroxisomal purpose

MOLECULAR MICROBIOLOGY, Issue 3 2004
Marilyn Parsons
Summary Peroxisomes are membrane-bounded organelles that compartmentalize a variety of metabolic functions. Perhaps the most divergent peroxisomes known are the glycosomes of trypanosomes and their relatives. The glycolytic pathway of these organisms resides within the glycosome. The development of robust molecular genetic and proteomic approaches coupled with the completion of the genome sequence of the pathogens Trypanosoma brucei, Trypanosoma cruzi, and Leishmania major provides an opportunity to determine the complement of proteins within the glycosome and the function of compartmentation. Studies now suggest that regulation of glycolysis is a strong driving force for maintenance of the glycosome. [source]

How do helix,helix interactions help determine the folds of membrane proteins?

PROTEIN SCIENCE, Issue 4 2003
Perspectives from the study of homo-oligomeric helical bundles
FRET, fluorescence resonance energy transfer; NBD, 7-nitrobenz-2-oxa-1,3-diazole; C-14 betaine, N -tetradecyl- N,N -dimethyl-3-ammonio-1-propanesulfonate; MF, mole fraction Abstract The final, structure-determining step in the folding of membrane proteins involves the coalescence of preformed transmembrane helices to form the native tertiary structure. Here, we review recent studies on small peptide and protein systems that are providing quantitative data on the interactions that drive this process. Gel electrophoresis, analytical ultracentrifugation, and fluorescence resonance energy transfer (FRET) are useful methods for examining the assembly of homo-oligomeric transmembrane helical proteins. These methods have been used to study the assembly of the M2 proton channel from influenza A virus, glycophorin, phospholamban, and several designed membrane proteins,all of which have a single transmembrane helix that is sufficient for association into a transmembrane helical bundle. These systems are being studied to determine the relative thermodynamic contributions of van der Waals interactions, conformational entropy, and polar interactions in the stabilization of membrane proteins. Although the database of thermodynamic information is not yet large, a few generalities are beginning to emerge concerning the energetic differences between membrane and water-soluble proteins: the packing of apolar side chains in the interior of helical membrane proteins plays a smaller, but nevertheless significant, role in stabilizing their structure. Polar, hydrogen-bonded interactions occur less frequently, but, nevertheless, they often provide a strong driving force for folding helix,helix pairs in membrane proteins. These studies are laying the groundwork for the design of sequence motifs that dictate the association of membrane helices. [source]

ISO 14001 , experiences, effects and future challenges: a national study in Austria

BUSINESS STRATEGY AND THE ENVIRONMENT, Issue 2 2007
Elisabeth Schylander
Abstract More than 60000 organizations worldwide have implemented environmental management systems (EMSs). About 800 of them are located in Austria. As Austria was one of the leading countries in promoting the EU scheme EMAS, and as there has been no specific study on Austrian experiences with ISO 14001, the purpose of this study is to describe the experiences with and effects of ISO 14001 in Austria. The results show that ISO 14001 often leads to reduced environmental impact, especially in the area of waste. A strong driving force behind implementation is the expected improvement of an organization's image. The average repayment time on an investment in an EMS is less than two years. Legal compliance tends to be difficult to implement, but on the other hand it works well in daily practice. To develop an EMS into a sustainability management system, the two most important challenges are to improve coordination between the EMS and the organization's strategies and to synchronize the EMS with central value chains. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment. [source]

New Developments in Simulated Moving Bed Chromatography

CHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 6 2008
A. Seidel-Morgenstern
Abstract Chromatographic separation processes are widely used to isolate and purify value added products. Most frequently, such separation processes are performed exploiting the principles of injecting samples of the feed mixture in a repetitive periodic manner and collecting the target products batchwise. In the early 1960s, an alternative operation principle based on using several columns connected in series and exploiting a continuous countercurrent movement between the mobile and stationary phases initiated significant improvements in performing specific separation processes in the petrochemical and sugar industries. In the last decade, the so-called simulated moving bed (SMB) chromatography has rapidly entered the pharmaceutical industry. In particular enantioseparations using chiral stationary phases have become a strong driving force to develop more sophisticated concepts of continuous chromatography. Currently, the growing interest in efficient methods for the downstream processing of biomolecules enhances interest in SMB processes. This paper gives a brief overview of the new suggestions and trends. [source]