A multipurpose immobilized biocatalyst with pectinase, xylanase and cellulase activities

<p>Abstract</p> <p>Background</p> <p>The use of immobilized enzymes for catalyzing various biotransformations is now a widely used approach. In recent years, cross-linked enzyme aggregates (CLEAs) have emerged as a novel and versatile biocatalyst design. The present work deals with the preparation of a CLEA from a commercial preparation, Pectinex™ Ultra SP-L, which contains pectinase, xylanase and cellulase activities. The CLEA obtained could be used for any of the enzyme activities. The CLEA was characterized in terms of kinetic parameters, thermal stability and reusability in the context of all the three enzyme activities.</p> <p>Results</p> <p>Complete precipitation of the three enzyme activities was obtained with n-propanol. When resulting precipitates were subjected to cross-linking with 5 mM glutaraldehyde, the three activities initially present (pectinase, xylanase and cellulase) were completely retained after cross-linking. The V_max/K_mvalues were increased from 11, 75 and 16 to 14, 80 and 19 in case of pectinase, xylanase and cellulase activities respectively. The thermal stability was studied at 50°C, 60°C and 70°C for pectinase, xylanase and cellulase respectively. Half-lives were improved from 17, 22 and 32 minutes to 180, 82 and 91 minutes for pectinase, xylanase and cellulase respectively. All three of the enzymes in CLEA could be reused three times without any loss of activity.</p> <p>Conclusion</p> <p>A single multipurpose biocatalyst has been designed which can be used for carrying out three different and independent reactions; 1) hydrolysis of pectin, 2) hydrolysis of xylan and 3) hydrolysis of cellulose. The preparation is more stable at higher temperatures as compared to the free enzymes.</p

ERG finally has something to YAP about in prostate cancer

SummaryThe significance of ERG in human prostate cancer is unclear because mouse prostate is resistant to ERG-mediated transformation. We determined that ERG activates the transcriptional program regulated by YAP1 of the Hippo signaling pathway and found that prostate-specific activation of either ERG or YAP1 in mice induces similar transcriptional changes and results in age-related prostate tumors. ERG binds to chromatin regions occupied by TEAD/YAP1 and transactivates Hippo target genes. In addition, in human luminal-type prostate cancer cells, ERG binds to the promoter of YAP1 and is necessary for YAP1 expression. These results provide direct genetic evidence of a causal role for ERG in prostate cancer and reveal a connection between ERG and the Hippo signaling pathway

PDBe: improved findability of macromolecularstructure data in the PDB

© 2019 The Authors. Published by OUP. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1093/nar/gkz990The Protein Data Bank in Europe (PDBe), a founding member of the Worldwide Protein Data Bank (wwPDB), actively participates in the deposition, curation, validation, archiving and dissemination of macromolecular structure data. PDBe supports diverse research communities in their use of macromolecular structures by enriching the PDB data and by providing advanced tools and services for effective data access, visualization and analysis. This paper details the enrichment of data at PDBe, including mapping of RNA structures to Rfam, and identification of molecules that act as cofactors. PDBe has developed an advanced search facility with ∼100 data categories and sequence searches. New features have been included in the LiteMol viewer at PDBe, with updated visualization of carbohydrates and nucleic acids. Small molecules are now mapped more extensively to external databases and their visual representation has been enhanced. These advances help users to more easily find and interpret macromolecular structure data in order to solve scientific problems.The Protein Data Bank in Europe is supported by European Molecular Biology Laboratory-European Bioinformatics Institute; Wellcome Trust [104948]; Biotechnology and Biological Sciences Research Council [BB/N019172/1, BB/G022577/1, BB/J007471/1, BB/K016970/1, BB/K020013/1, BB/M013146/1, BB/M011674/1, BB/M020347/1, BB/M020428/1, BB/P024351/1]; European Union [284209]; ELIXIR and Open Targets. Funding for open access charge: EMB

State, corruption, postcoloniality: A conversation with Akhil Gupta on the 20th anniversary of "Blurred Boundaries"

"Blurred Boundaries: The Discourse of Corruption, the Culture of Politics, and the Imagined State," by Akhil Gupta, first appeared in print in 1995 in the pages of American Ethnologist. It went on to become one of the most important and influential articles of recent decades. We talked with Akhil Gupta about how the argument put forward in "Blurred Boundaries" came to be. Our conversation touched on the background of the article and the difficulties in getting it published; the relationship of the article to postcolonial scholarship, subaltern studies, feminist studies, and the then emerging literature on globalization; its relationship with other theorists of the state through themes such as Eurocentrism, reification, fantasy, fetishism, and the role of culture in the analysis of the state; and future directions in research on the state, among them, examining emotion and affect, studying the most powerful bureaucracies in nation-states, and developing the emergent literature on corruption

State, corruption, postcoloniality: A conversation with Akhil Gupta on the 20th anniversary of "Blurred Boundaries"

"Blurred Boundaries: The Discourse of Corruption, the Culture of Politics, and the Imagined State," by Akhil Gupta, first appeared in print in 1995 in the pages of American Ethnologist. It went on to become one of the most important and influential articles of recent decades. We talked with Akhil Gupta about how the argument put forward in "Blurred Boundaries" came to be. Our conversation touched on the background of the article and the difficulties in getting it published; the relationship of the article to postcolonial scholarship, subaltern studies, feminist studies, and the then emerging literature on globalization; its relationship with other theorists of the state through themes such as Eurocentrism, reification, fantasy, fetishism, and the role of culture in the analysis of the state; and future directions in research on the state, among them, examining emotion and affect, studying the most powerful bureaucracies in nation-states, and developing the emergent literature on corruption

Reduction Of Cyclic Variations By Using Advanced Ignition Systems In A Lean-Burn Stationary Natural Gas Engine Operating At 10 Bar Bmep And 1800 Rpm

In stationary natural gas engines, lean-burn combustion offers higher engine efficiencies with simultaneous compliance with emission regulations. A prominent problem that one encounters with lean operation is cyclic variations. Advanced ignition systems offer a potential solution as they suppress cyclic variations in addition to extending the lean ignition limit. In this article, the performance of three ignition systems-conventional spark ignition (SI), single-point laser ignition (LI), and prechamber equipped laser ignition (PCLI)-in a single-cylinder natural gas engine is presented. First, a thorough discussion regarding the efficacy of several metrics, besides coefficient of variation of indicated mean effective pressure (COV_IMEP), in representing combustion instability is presented. This is followed by a discussion about the performance of the three ignition systems at a single operational condition, that is, same excess air ratio (λ) and ignition timing (IT). Next, these metrics are compared at the most optimal operational points for each ignition system, that is, at points where λ and IT are optimized to achieve highest efficiency. From these observations, it is noted that PCLI achieves the highest increase in engine efficiency, Δη = 2.1% points, and outperforms the other two methods of ignition. A closer look reveals that the coefficient of variation in ignition delay (COV_ID) was negligible, whereas that in coefficient of variation in combustion duration (COV_CD) was significantly lower by 2.2% points. However, the metrics COV_ID and COV_CD are not well correlated with COV_IMEP

Review: laser ignition for aerospace propulsion

Renewed interest in the use of high-speed ramjets and scramjets and more efficient lean burning engines has led to many subsequent developments in the field of laser ignition for aerospace use and application. Demands for newer, more advanced forms of ignition, are increasing as individuals strive to meet regulations that seek to reduce the level of pollutants in the atmosphere, such as CHx, NOx, and SO2. Many aviation gas turbine manufacturers are interested in increasing combustion efficiency in engines, all the while reducing the aforementioned pollutants. There is also a desire for a new generation of aircraft and spacecraft, utilizing technologies such as scramjet propulsion, which will never realize their fullest potential without the use of advanced ignition processes. These scenarios are all limited by the use of conventional spark ignition methods, thus leading to the desire to find new, alternative methods of ignition. This paper aims to provide the reader an overview of advanced ignition methods, with an emphasis on laser ignition and its applications to aerospace propulsion. A comprehensive review of advanced ignition systems in aerospace applications is performed. This includes studies on gas turbine applications, ramjet and scramjet systems, and space and rocket applications. A brief overview of ignition and laser ignition phenomena is also provided in earlier sections of the report. Throughout the reading, research papers, which were presented at the 2nd Laser Ignition Conference in April 2014, are mentioned to indicate the vast array of projects that are currently being pursued

Performance Of Laser And Spark Ignition Systems In A Reciprocating Natural Gas Engine

Lean-burn natural gas engines remain attractive as they offer low emissions with simultaneous high engine efficiency. The low carbon to hydrogen ratio in natural gas minimizes the carbon dioxide emission, while the low-temperature operation reduces NOx formation. However, to preserve engine specific power, turbo-charged operation is required, which results in an unfavorable environment for the spark ignition system. In this study, the performance of three ignition systems - Spark Ignition (SI), Laser Ignition (LI), and Prechamber Laser Ignition (PCLI) - were assessed through tests in a single-cylinder natural gas engine. Both ? and ignition timing sweeps were performed while maintaining a constant speed of 1800 rpm and a load of 10 bar BMEP. Emissions and combustion data analysis, while complying with allowable emission regulation and ignition stability requirements, showed the best performance to be achieved with the PCLI system. This is attributed to improved ignition with the use of a laser, volumetric ignition facilitated by spatially distributed flame jets, and increased in-cylinder turbulence. This results in reduced ignition delay and shortened combustion duration