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Access Foundation Programmes are a widening-participation initiative designed to encourage engagement in higher education among underrepresented groups, including those with socioeconomic and educational disadvantage. In particular, mature students enrolled in these programmes experience greater difficulties making the transition to tertiary education, especially when they opt to study disciplines traditionally considered difficult. Computer programming is perceived as a traditionally difficult subject with typically lower pass rates and progression rates than other subjects. This paper describes the first of a three-cycle action research study examining the perceived effects of a structured Peer Assisted Learning (PAL) Programme for mature students enrolled in a computer science programming module for an Access Foundation Programme in an Irish University. The focus of this qualitative study was to evaluate the perceived effect of a PAL programme on learning and whether it offered a positive learning support structure. Findings from our study suggest that PAL programmes have an overall positive effect on subject comprehension as well as enhanced learner confidence for mature Access Foundation students. Furthermore, PAL sessions offered students a support structure that helped with their transition and acculturation to tertiary education. This study also highlights the importance the PAL leader's role has on the perceived effectiveness of the PAL sessions as well as the impact of the students' shared history on the near-peer bond. The study concludes that the implementation of PAL programmes for Access Foundation Programmes has the potential to offer mature students a supportive learning environment and to improve their learning experience.

Laboratory training is key to many science subjects and those that teach the practical laboratory skills maintain a pivotal role in undergraduate science training. Graduate Teaching Assistants (GTAs) are regularly used in higher education institutes to teach these practical lab skills. The GTA can be involved in both laboratory teaching and assessing all levels of undergraduates. This varied and challenging role requires support from the institute and if appropriately provided the learning experience can be rewarding not only for the undergraduate, but also for the GTA. In this review, the critical role of the laboratory GTA will be examined, their support requirement highlighted and the multi-dimensional benefits of GTA facilitated research-orientated laboratory learning outlined.

This paper describes how three technologies were utilised in combination to align student learning and assessment as part of a case study. Multiple choice questions (MCQs) were central to all these technologies. The peer learning technologies; Personal Response Devices (a.k.a. "Clickers") and "PeerWise" (http://peerwise.cs.auckland.ac.nz), were implemented to achieve scaffolded, self-directed independent learning by the students which aligned to the assessment methodology through creating, analysing, answering and discussing multiple choice questions. Personal response devices enhanced in-class activity involvement, whilst PeerWise provided structure and support for independent student learning through defined outside class activities. An associated technology, online MCQs hosted though a secure virtual learning environment, was used as an aligned assessment methodology. The rationale behind this case study, its implementation and evaluation are described and discussed. Finally, the potential widespread applicability of this aligned, technology-enhanced learning and assessment methodology is outlined along with suggestions and guidelines to aid practitioners wishing to implement a similar approach. Contains notes and references.

Tirza Meyer's book, "Elisabeth Mann Borgese and the Law of the Sea," provides a comprehensive account of the Third United Nations Convention on the Law of the Sea (UNCLOS III) and the negotiations surrounding the stretch of seabed beyond national jurisdiction. The book focuses on the perspective of Elisabeth Mann Borgese, who played a significant role in shaping the history of UNCLOS III. Meyer skillfully weaves together legal history and the personal story of Mann Borgese, highlighting the tensions between political idealism and self-interested power politics. The book also sheds light on unresolved historical mysteries and the complex international politics that influenced the development of the Law of the Sea. [Extracted from the article]

Sanjay Chaturvedi and Timothy Doyle Climate Terror: A Critical Geopolitics of Climate Change. Basingstoke: Palgrave Macmillan, 2015; ISBN 9780230249622, RRP 24.99[pounds sterling] Within the last year or so, a number [...]

Abstract This article examines proposals for the reform of the relationship between internal security and state-society relations in Northern Ireland and finds a divergence from the usual liberal package of [...]

This mixed-methods, investigative case study explores the experience of a virtual learning environment (VLE) change and its effect on the use of digital learning tools specifically, and teaching practice more generally, for chemistry lecturers at TU Dublin (Ireland) prior to pandemic of the coronavirus disease COVID-19. Initially, a questionnaire examined the different teaching identities the participating lecturers might have and how they relate to the literature. These identities were examined under the following themes: sense of achievement, motivational factors for innovation, innovation positioning, as well as social and organizational factors influencing the decision making. A visual approach of representing the questionnaire data, termed 'Lecturer Landscapes', was developed which uncovered new trends based on the biographical descriptors of the research population. Subsequent interviews led to a more detailed investigation of the themes noted in the questionnaire and the Lecturer Landscapes to more holistically capture the professional identity of each respondent. The lens of experience during a VLE change was used to frame each respondent's professional identity in context. Overall, a VLE change does not have to effect teaching practice and can be experienced as a positive change in teaching and learning. It was also noted that innovation can only occur when specific, and individual, needs and problems are addressed and when personal development is promoted by intrinsic, rather than extrinsic, motivational factors. [ABSTRACT FROM AUTHOR]

Abstract Background Horseradish Peroxidase (HRP) plays important roles in many biotechnological fields, including diagnostics, biosensors and biocatalysis. Often, it is used in immobilised form. With conventional immobilisation techniques, the enzyme adheres in random orientation: the active site may face the solid phase rather than bulk medium, impeding substrate access and leading to sub-optimal catalytic performance. The ability to immobilise HRP in a directional manner, such that the active site would always face outwards from the insoluble matrix, would maximise the immobilised enzyme's catalytic potential and could increase HRP's range of actual and potential applications. Results We have replaced arginine residues on the face of glycan-free recombinant HRP opposite to the active site by lysines. Our strategy differs from previous reports of specific HRP immobilisation via an engineered affinity tag or single reactive residue. These conservative Arg-to-Lys substitutions provide a means of multipoint covalent immobilisation such that the active site will always face away from the immobilisation matrix. One triple and one pentuple mutant were generated by substitution of solvent-exposed arginines on the "back" of the polypeptide (R118, R159 and R283) and of residues known to influence stability (K232 and K241). Orientated HRP immobilisation was demonstrated using a modified polyethersulfone (PES) membrane; the protein was forced to orientate its active site away from the membrane and towards the bulk solution phase. Mutant properties and bioinformatic analysis suggested the reversion of K283R to improve stability, thus generating two additional mutants (K118/R159K and R118K/K232N/K241F/R283K). While most mutants were less stable in free solution than wild type rHRP, the quadruple revertant regained some stability over its mutant counterparts. A greater degree of immobilisation on CNBr-activated Sepharose™ was noted with increased lysine content; however, only marginal gains in solvent stability resulted from immobilisation on this latter matrix. Conclusion Directional, orientated, immobilisation of rHRP mutants onto an activated, modified polyethersulfone membrane has been achieved with excellent retention of catalytic activity; however, re-engineering of acceptable stability characteristics into the "immobilisation mutants" will determine their applicability in diagnosis and biosensor development.

This article details the evolution of maritime security from the perspective of its impact on the historical architecture of sea space. It argues that, as the fundamental unit of governance, zoning provides keen insight into the mechanics of maritime security. The article observes that Britain's Hovering Acts in the late eighteenth century represent the earliest example of modern zonation at sea and that they exhibit a shift from early modern territorial claims based on imperium and dominium. The article explores the way these hovering zones shaped the rationale underlying contemporary maritime security. It finds that maritime security has effectively relegated national security to a minor spatial belt of state power, while elevating non-traditional understandings of security to the level of global existential threat. The future of maritime security is under construction. Increasingly segmented by interconnecting, overlapping, multi-functional zones that seek to regulate all free movement and usage of the sea, security developments are reorganizing the maritime sphere. Nonetheless, the article argues, despite the novelty of this development, a historical military logic persists in new formations of security-oriented practices of maritime governance. [ABSTRACT FROM AUTHOR]

In this introduction to a special section of the September 2019 issue of International Affairs , we revisit the main themes and arguments of our article 'Beyond seablindness: a new agenda for maritime security studies', published in this journal in November 2017. We reiterate our call for more scholarly attention to be paid to the maritime environment in international relations and security studies. We argue that the contemporary maritime security agenda should be understood as an interlinked set of challenges of growing global, regional and national significance, and comprising issues of national, environmental, economic and human security. We suggest that maritime security is characterized by four main characteristics, including its interconnected nature, its transnationality, its liminality—in the sense of implicating both land and sea—and its national and institutional cross-jurisdictionality. Each of the five articles in the special section explores aspects of the contemporary maritime security agenda, including themes of geopolitics, international law, interconnectivity, maritime security governance and the changing spatial order at sea. [ABSTRACT FROM AUTHOR]

-glucosidases are a class of enzyme that are widely distributed in the living world, with examples noted in plants, fungi, animals and bacteria. They offer both hydrolysis and synthesis capacity for a wide range of biotechnological processes. However, the availability of native, or the production of recombinant β-glucosidases, is currently a bottleneck in the widespread industrial application of this enzyme. In this present work, the production of recombinant β-glucosidase from Streptomyces griseus was optimised using a Design of Experiments strategy, comprising a two-stage, multi-model design. Three screening models were comparatively employed: Fractional Factorial, Plackett-Burman and Definitive Screening Design. Four variables (temperature, incubation time, tryptone, and OD600 nm) were experimentally identified as having statistically significant effects on the production of S.griseus recombinant β-glucosidase in E. coli BL21 (DE3). The four most influential variables were subsequently used to optimise recombinant β-glucosidase production, employing Central Composite Design under Response Surface Methodology. Optimal levels were identified as: OD600 nm, 0.55; temperature, 26 °C; incubation time, 12 h; and tryptone, 15 g/L. This yielded a 2.62-fold increase in recombinant β-glucosidase production, in comparison to the pre-optimised process. Affinity chromatography resulted in homogeneous, purified β-glucosidase that was characterised in terms of pH stability, metal ion compatibility and kinetic rates for p-nitrophenyl-β-D-glucopyranoside (pNPG) and cellobiose catalysis. [ABSTRACT FROM AUTHOR]

The paper forms a Foucauldian analysis of police reforms in Montenegro. Drawing on interviews with police officers at all ranks in 2004, undertaken as reform was commencing, and on interviews undertaken in 2010, after Montenegro's independence, the paper explores the biopolitics of liberalisation. The paper aims to demonstrate norms of internal security liberalisation that operate beyond a legal understanding of state power. It illustrates the operation of a rule of police that produces norms conducive to the governance of a dynamic market state. It argues that the rule of police subsists within but also subverts the rule of law and the human rights approach to democratic development. [ABSTRACT FROM AUTHOR]

Over the past decade, there has been a societal push for social inclusion in Ireland for students with special educational needs (SEN). As a result, the number of dedicated special needs schools has dramatically decreased across the country as students with SEN enrol, instead, in mainstream schools. Dedicated SEN schools provided an environment in which students with a general learning difficulty (GLD) could develop at a pace suited to them. However, this developmental pace is different for GLD students in a mainstream school. This research explores the social development of students with a GLD in a mainstream school in postprimary education in Ireland. Informed by educational policies, both national and international, this research aims to find whether we are, as a society, inclusive of all educational needs in postprimary education, specifically students with GLD. The research question explicitly explores if students with a GLD have enhanced social development as a result of being part of a mainstream school setting. Employing a mixed methods case-study methodology, key emergent themes were observed and, overall, it was concluded that in a suitable environment, both physical and cultural, the social skills of students with a GLD can improve, primarily through increased social interaction with their peers. [ABSTRACT FROM AUTHOR]

The production of high yields of soluble recombinant protein is one of the main objectives of protein biotechnology. Several factors, such as expression system, vector, host, media composition and induction conditions can influence recombinant protein yield. Identifying the most important factors for optimum protein expression may involve significant investment of time and considerable cost. To address this problem, statistical models such as Design of Experiments (DoE) have been used to optimise recombinant protein production. This reviewexamines the application ofDoE in the production of recombinant proteins in prokaryotic expression systems with specific emphasis onmedia composition and culture conditions. The review examines the most commonly used DoE screening and optimisation designs. It provides examples of DoE applied to optimisation of media and culture conditions. [ABSTRACT FROM AUTHOR]

The article discusses performative politics that challenges philosopher Peter Sloterdijk’s pseudonism. It questions Sloterdijk’s understanding of democracy and situating it in relation to some of Sloterdijk’s recent and controversial political activities. It is opined that Sloterdijk’s claim of authenticity is his unacknowledged pseudonym through which he attempts to revive, re-empower and render authentic the noble lie for the post-truth age.

This paper examines power relations along the African coast of the Indian Ocean in terms of space and time. Spatial strategies, it argues, are swiftly emerging through zoning mechanisms which territorialise the governance of ocean space. These strategies can supplement and disrupt more traditional temporal strategies, which facilitate speed and freedom of movement for commercial and military traffic. The article focusses on the US proposition to provide maritime security sector reform to African coastal states as a form of temporal strategy designed to shape new zoning practices in favour of freedom of movement. The paper concludes by arguing that the US strategy implies a policing approach that generates maritime surveillance capacities along land–sea lanes of communication. It contrasts this surface form of knowledge with the need for African coastal states to generate the sort of oceanographic data presently undergirding the emerging blue economies of Europe. [ABSTRACT FROM AUTHOR]

Abstract: Voltage-dependent potassium channels (Kv) are involved in various cellular signalling processes by governing the membrane potential of excitable cells. The cytosolic face of these α subunit-containing channels is associated with β subunits that can modulate channel responses. Surprisingly, the β subunit of the mammalian Kv1 channels, Kvβ2, has a high level of sequence homology with the aldo–keto reductase (AKR) superfamily of proteins. Recent studies have shown that Kvβ2 can catalyze the reduction of aldehydes and, most significantly, that channel function is modulated when Kvβ2-bound NADPH is concomitantly oxidized. As a result, the redox chemistry of this subunit is crucial to understanding its role in K+ channel modulation. The present study has extended knowledge of the substrate profile of this subunit using a single turnover fluorimetric assay. Kvβ2 was found to catalyse the reduction of aromatic aldehyde substrates such as 2, 3 and 4-nitrobenzaldehydes, 4-hydroxybenzaldehyde, pyridine 2-aldehyde and benzaldehyde. The presence of an electron withdrawing group at the position para to the aldehyde in aromatic compounds facilitated reduction. Aliphatic aldehydes proved to be poor substrates. We devised a simple HPLC-based assay to identify Kvβ2 reaction products. Using this assay we showed, for the first time, that Kvβ2 can catalyze a slow aldehyde dismutation reaction using 4-nitrobenzaldehyde as substrate and have identified the products of this reaction. The ability of Kvβ2 to carry out both an aldehyde reduction and a dismutation reaction is discussed in the light of current thinking on the role of redox chemistry in channel modulation. [Copyright &y& Elsevier]

The present article analyses the role of the District Policing Partnership Boards conceptualized by the Patten Report as a pivotal aspect of policing reform in Northern Ireland. It argues that, as originally envisaged, these Boards possessed a participatory capacity to transform rigid institutionalized relations of power between state and society. In outlining their potential the article aims to highlight the difference between traditional consultation mechanisms and more communicative-based participatory policing. The article analyses the reasons why this more radical model was rejected and examines the impact of this on the operation of District Policing Partnerships. It concludes that the consultative mechanisms that emerged have so far contributed little to the structural transformation of police-society relations in Northern Ireland. [ABSTRACT FROM AUTHOR]

Abstract: Horseradish peroxidase (HRP) has long attracted intense research interest and is used in many biotechnological fields, including diagnostics, biosensors and biocatalysis. Enhancement of HRP catalytic activity and/or stability would further increase its usefulness. Based on prior art, we substituted solvent-exposed lysine and glutamic acid residues near the proximal helix G (Lys 232, 241; Glu 238, 239) and between helices F and F′ (Lys 174). Three single mutants (K232N, K232F, K241N) demonstrated increased stabilities against heat (up to 2-fold) and solvents (up to 4-fold). Stability gains are likely due to improved hydrogen bonding and space-fill characteristics introduced by the relevant substitution. Two double mutants showed stability gains but most double mutations were non-additive and non-synergistic. Substitutions of Lys 174 or Glu 238 were destabilising. Unexpectedly, notable alterations in steady-state V m/E values occurred with reducing substrate ABTS (2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid)), despite the distance of the mutated positions from the active site. [Copyright &y& Elsevier]

Abstract: The enzyme horseradish peroxidase has many uses in biotechnology but a stabilized derivative would have even wider applicability. To enhance thermal stability, we applied consensus mutagenesis (used successfully with other proteins) to recombinant horseradish peroxidase and generated five single-site mutants. Unexpectedly, these mutations had greater effects on steady-state kinetics than on thermal stability. Only two mutants (T102A, T110V) marginally exceeded the wild type''s thermal stability (4% and 10% gain in half-life at 50°C respectively); the others (Q106R, Q107D, I180F) were less stable than wild type. Stability of a five-fold combination mutant matched that of Q106R, the least-stable single mutant. These results were perplexing: the Class III plant peroxidases display wide differences in thermal stability, yet the consensus mutations failed to reflect these natural variations. We examined the sequence content of Class III peroxidases to determine if there are identifiable molecular reasons for the stability differences observed. Bioinformatic analysis validated our choice of sites and mutations and generated an archetypal peroxidase sequence for comparison with extant sequences. It seems that both genetic variation and differences in protein stability are confined to non-helical regions due to the presence of a highly conserved alpha-helical structural scaffold in these enzymes. [Copyright &y& Elsevier]

Abstract: Horseradish peroxidase (HRP) is a commonly used enzyme in many biotechnological fields. Improvement of HRP stability would further increase its potential application range. In the present study, 13 single- and three double-mutants of solvent exposed, proximal lysine and glutamic acid residues were analysed for enhanced H2O2 stability. Additionally, five single- and one pentuple-consensus mutants were investigated. Most mutants displayed little or no alteration in H2O2 stability; however, three (K232N, K241F and T110V) exhibited significantly increased H2O2 tolerances of 25- (T110V), 18- (K232N), and 12-fold (K241F). This improved stability may be due to an altered enzyme-H2O2 catalysis pathway or to removal of potentially oxidisable residues. [Copyright &y& Elsevier]

Based on research undertaken in southern Serbia following the introduction of multi-ethnic policing units, this article examines the pluralist intentions behind attempts to democratize security through community-oriented policing (COP). It details the achievements and the limitations of attempts to institute multi-ethnic policing as a foundational strategy for COP. Evidence is presented that the reforms did not sufficiently empower local actors over centralized institutions. The article illustrates the limitations of COP, arguing that de-securitization requires the creation of spaces wherein the local order being maintained by a locally accountable police is open to deliberation. [ABSTRACT FROM AUTHOR]

Background: Horseradish Peroxidase (HRP) plays important roles in many biotechnological fields, including diagnostics, biosensors and biocatalysis. Often, it is used in immobilised form. With conventional immobilisation techniques, the enzyme adheres in random orientation: the active site may face the solid phase rather than bulk medium, impeding substrate access and leading to sub-optimal catalytic performance. The ability to immobilise HRP in a directional manner, such that the active site would always face outwards from the insoluble matrix, would maximise the immobilised enzyme's catalytic potential and could increase HRP's range of actual and potential applications. Results: We have replaced arginine residues on the face of glycan-free recombinant HRP opposite to the active site by lysines. Our strategy differs from previous reports of specific HRP immobilisation via an engineered affinity tag or single reactive residue. These conservative Arg-to-Lys substitutions provide a means of multipoint covalent immobilisation such that the active site will always face away from the immobilisation matrix. One triple and one pentuple mutant were generated by substitution of solvent-exposed arginines on the "back" of the polypeptide (R118, R159 and R283) and of residues known to influence stability (K232 and K241). Orientated HRP immobilisation was demonstrated using a modified polyethersulfone (PES) membrane; the protein was forced to orientate its active site away from the membrane and towards the bulk solution phase. Mutant properties and bioinformatic analysis suggested the reversion of K283R to improve stability, thus generating two additional mutants (K118/R159K and R118K/K232N/K241F/R283K). While most mutants were less stable in free solution than wild type rHRP, the quadruple revertant regained some stability over its mutant counterparts. A greater degree of immobilisation on CNBr-activated Sepharos™ was noted with increased lysine content; however, only marginal gains in solvent stability resulted from immobilisation on this latter matrix. Conclusion: Directional, orientated, immobilisation of rHRP mutants onto an activated, modified polyethersulfone membrane has been achieved with excellent retention of catalytic activity; however, re-engineering of acceptable stability characteristics into the "immobilisation mutants" will determine their applicability in diagnosis and biosensor development. [ABSTRACT FROM AUTHOR]

Caffeine is a plant alkaloid present in food and beverages consumed worldwide. It has high lipid solubility with recognized actions in the central nervous system and in peripheral tissues, notably the adipose depots. However, the literature is scant regarding caffeine's influence on adipocyte functions other than lipolysis, such as glucose incorporation into lipids (lipogenesis) and amine oxidation. The objective of this study was to explore the direct effects of caffeine and of isobutylmethylxanthine (IBMX) on these adipocyte functions. Glucose transport into fat cells freshly isolated from mice, rats, or humans was monitored by determining [3H]-2-deoxyglucose (2-DG) uptake, while the incorporation of radiolabeled glucose into cell lipids was used as an index of lipogenic activity. Oxidation of benzylamine by primary amine oxidase (PrAO) was inhibited by increasing doses of caffeine in human adipose tissue preparations with an inhibition constant (Ki) in the millimolar range. Caffeine inhibited basal and insulin-stimulated glucose transport as well as lipogenesis in rodent adipose cells. The antilipogenic action of caffeine was also observed in adipocytes from mice genetically invalidated for PrAO activity, indicating that PrAO activity was not required for lipogenesis inhibition. These caffeine inhibitory properties were extended to human adipocytes: relative to basal 2-DG uptake, set at 1.0 ± 0.2 for 6 individuals, 0.1 mM caffeine tended to reduce uptake to 0.83 ± 0.08. Insulin increased uptake by 3.86 ± 1.11 fold when tested alone at 100 nM, and by 3.21 ± 0.80 when combined with caffeine. Our results reinforce the recommendation of caffeine's potential in the treatment or prevention of obesity complications. [ABSTRACT FROM AUTHOR]

Pseudomonads are one of the most studied species of bacteria as they display remarkable metabolic and physiological versatility. This enables them to colonize a wide variety of terrestrial and aquatic habitats, generating biotechnologically interesting enzymes. Here, the partial purification and characterization of a novel, extracellularly-produced, lipase from Pseudomonas brenneri is described. The partially purified lipase was active over a broad pH range (5.0–9.0) and was stable at 70 °C for 45 min. The lipase displayed significant stability, and in some cases activation, in the presence of organic solvents with log P ≥ 2.0. Such stability characteristics indicated that this lipase could potentially be useful as a biocatalyst for biodiesel production. This was subsequently demonstrated through the facile production of Fatty Acid Methyl Esters in the presence of olive oil and methanol. Possible applications for this novel, stable lipase include the bioremediation of oil in the environment. • A novel lipase, from an under explored Pseudomonas genus has been isolated and characterised. • The novel lipase displays excellent thermo-organo-stability. • The novel lipase readily catalyzed Fatty Acid Methyl Ester synthesis in the presence of olive oil and methanol. [ABSTRACT FROM AUTHOR]

Methylxanthines are among the most widely consumed drugs in the world and evidence of their health benefits has been growing in recent years. Primary Amine Oxidase (PrAO) has been recognized as a therapeutic target for the amelioration of inflammatory, vascular, and neurodegenerative diseases. Previous work in our laboratories showed that caffeine inhibited Bovine PrAO with a Ki of 1.0 mM using benzylamine as substrate. This study aimed to extend our previous work and explore the possibility that related methylxanthines might influence PrAO activity. While paraxanthine, theophylline, and 7‐methylxanthine had little effect on PrAO, theobromine was a noncompetitive inhibitor with a Ki of 276 ± 44 µM. The specific structural elements of methylxanthines that are required for inhibition allow us to suggest that their binding site on PrAO may be a target for therapeutics. The health benefits associated with dietary methylxanthine consumption could involve PrAO inhibition. Practical applications: Inhibition of PrAO by methylxanthines may be significant in conferring health benefits. The design of PrAO inhibitors based on the structural motifs identified in this study (N‐methylation at specific locations) is indicated. Existing therapeutics based on a core xanthine structure can be evaluated for their effects on PrAO. PrAO inhibition must be considered as a potential mediator of the beneficial health effects of some methylxanthines. If inhibition in human tissues is comparable to, or greater than, that found in these studies it points to an important role for these compounds in human health. Theobromine, like caffeine, is a noncompetitive inhibitor of Primary Amine Oxidase (PrAO). Xanthine methylation at positions 3 and 7 is required for inhibition of PrAO. The methylxanthine binding site on PrAO may be a target for therapeutics. [ABSTRACT FROM AUTHOR]

The role of the redox state of Kvβ subunits in the modulation of Kv1 potassium channels has been well documented over the past few years. It has been suggested that a molecule that binds to or inhibits the aldo-keto reductase activity of Kvβ might affect the modulation of channel properties. Previous studies of possible modulators of channel activity have shown that cortisone and some related compounds are able to physically dissociate the channel components by binding to a site at the interface between α and β subunits. Herein, we describe some new inhibitors of rat brain Kvβ2, identified using an assay based on multiple substrate turnover. This approach allows one to focus on molecules that specifically block NADPH oxidation. These studies showed that, at 0.5 mM, 3,4-dihydroxphenylacetic acid (DOPAC) was an inhibitor of Kvβ2 turnover yielding a ∼40–50% reduction in the aldehyde reductase activity of this subunit. Other significant inhibitors include the bioflavinoid, rutin and the polyphenol resveratrol; some of the known cardioprotective effects of these molecules may be attributable to Kv1 channel modulation. Cortisone or catechol caused moderate inhibition of Kvβ2 turnover, and the aldo-keto reductases inhibitor valproate had an even smaller effect. Despite the importance of the Kv1 channels in a number of disease states, there have been few Kvβ2 inhibitors reported. While the ones identified in this study are only effective at high concentrations, they could serve as tools to decipher the role of Kvβ2 in vivo and, eventually, inform the development of novel therapeutics. [ABSTRACT FROM AUTHOR]

Abstract The Pseudomonas sp. have been long recognized for their exogenous lipolytic activities yet the genus still contains a lot of unexplored strains. Due to the versatile metabolic machinery and their potential for adaptation to fluctuating environmental conditions Pseudomonas sp. are of great interest for biotechnological applications. In this study, a new extracellularly produced lipolytic enzyme from Pseudomonas sp. (P. reinekei) was purified and characterized. The production of lipase from P. reinekei (H1) was enhanced 10-fold by optimizing the nitrogen source. The 50 kDa H1 lipase was purified using negative and positive mode anion exchange chromatography. The purified lipase was active over a broad pH range (5.0–9.0) and was stable for 24 h at 40 °C. The lipase showed significant stability, and indeed activation, in the presence of organic solvents with log P ≥ 2.0. These features render this lipase of interest as a biocatalyst for applications such as biodiesel production, detergent formulations and biodegradation of oil in the environment. Highlights • A novel lipase, from an under researched sub-species, has been isolated and fully characterised. • Production of this extracellular lipase was enhanced 10-fold through media engineering. • An innovative, two-stage anion exchange purification strategy was developed and optimised. • The novel lipase displays excellent organo-stability, and organo-activation, in the presence of organic solvents with log P ≥ 2.0. • This new lipase offers many biotechnological opportunities in non-aqueous biotransformations, detergent formulations and biodegradation of environmental waste oil. [ABSTRACT FROM AUTHOR]

Abstract: Toxic aldehydes produced by alcohol dehydrogenases have been implicated in the pathogenesis of Helicobacter pylori-related damage to the gastric mucosa. Despite this, the enzymes that might be responsible for producing such aldehydes have not been fully described. It was, therefore, of considerable interest to characterize the alcohol oxidizing enzymes in this pathogen. Previous work in this laboratory characterized two such H. pylori enzymes that had broad specificity for a range of aromatic alcohol substrates. However, an enzyme with specificity for aliphatic alcohols is likely to be required in order that H. pylori can metabolize the wide range of substrates encountered in the gastric mucosa. In this study we describe HpSCADH, an alcohol dehydrogenase from H. pylori 26695 with broad specificity for aliphatic alcohols. HpSCADH was classified in the cD1e subfamily of classical short chain alcohol dehydrogenases. The enzyme was a monomer of approximately 29kDa with a preference for NAD+ as cofactor. Pyrazole was found to be a competitive inhibitor of HpSCADH. The physiological role of this enzyme was explored by construction of an HpSCADH isogenic mutant. At pH 7.0 the mutant showed reduced growth which became more pronounced when the pH was lowered to 5.0. When pyrazole was added to wild type H. pylori cells it caused growth profiles to be reduced to match those of the isogenic mutant suggesting that HpSCADH inhibition alone was responsible for growth impairment. Taken together, the data relating to the alcohol metabolizing enzymes of this pathogen indicate that they play an important role in H. pylori growth and adaptation to acidic environments. The therapeutic potential of targeting H. pylori alcohol dehydrogenases is discussed. [Copyright &y& Elsevier]

All cells contain proteases, which hydrolyze the peptide bonds between amino acids of a protein backbone. Typically, proteases are prevented from nonspecific proteolysis by regulation and by their physical separation into different subcellular compartments; however, this segregation is not retained during cell lysis, which is the initial step in any protein isolation procedure. Prevention of proteolysis during protein purification often takes the form of a two-pronged approach: first, inhibition of proteolysis in situ, followed by the early separation of the protease from the protein of interest via chromatographic purification. Protease inhibitors are routinely used to limit the effect of the proteases before they are physically separated from the protein of interest via column chromatography. In this chapter, commonly used approaches to reducing or avoiding proteolysis during protein expression and purification are reviewed., (© 2023. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

The preparation of purified soluble proteins for biochemical studies is essential and the solubility of a protein of interest in various media is central to this process. Selectively altering the solubility of a protein is a rapid and economical step in protein purification and is based on exploiting the inherent physicochemical properties of a polypeptide. Precipitation of proteins, released from cells upon lysis, is often used to concentrate a protein of interest before further purification steps (e.g., ion exchange chromatography, size exclusion chromatography etc).Recombinant proteins may be expressed in host cells as insoluble inclusion bodies due to various influences during overexpression. Such inclusion bodies can often be solubilized to be reconstituted as functional, correctly folded proteins.In this chapter, we examine strategies for extraction/precipitation/solubilization of proteins for protein purification. We also present bioinformatic tools to aid in understanding a protein's propensity to aggregate/solubilize that will be a useful starting point for the development of protein extraction, precipitation, and selective re-solubilization procedures., (© 2023. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)