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Successful Strategy (successful + strategy)
Selected AbstractsBringing High Technology to Market: Successful Strategies Employed in the Worldwide Software IndustryTHE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 6 2006Chris Easingwood The launch stage can be critical for many new products, but particularly so for technology-intensive ones. This study examines this key stage in a high-tech sector: the worldwide computer software industry. Using a research instrument developed across a number of high-tech sectors, but adapted to the targeted sector, it describes a worldwide telephone-based survey of 300 organizations, resulting in 190 interviews, a response rate of 63%. It shows that five distinct and interpretable strategies are employed: (1) alliance strategy involves forming early strategic alliances as well as tactical alliances at the execution stage together with the development of unique distribution channels; (2) targeted low risk attempts to reduce the risk of adoption among identified segments by producing versions of the product specifically customized to the segments; (3) low-price original equipment manufacturer (OEM) is the only price-driven strategy and combines low price with channel building to OEMs who are looking for attractive price-to-performance ratios; (4) broadly based market preparation is an early-stage strategy that concentrates on educating the market vis-à-vis the technology and developing channels; and (5) niche-based technological superiority uses a technologically superior product to dominate a niche and corresponds closely to the chasm-crossing strategy expounded by Moore and others. Regarding superior product performance, successful software companies first of all engage in a broadly based preparation of the market but switch to a targeted strategy at the following stages of positioning and execution, built around superior technological performance and reduced risk. A somewhat different mix of strategies is adopted when the objective is superior market development, namely opening up new markets, reaching new customers, and developing new product platforms. Again the mix includes broadly based market preparation, this time along with alliances. This strategy is very much about working with partners. The broadly based market preparation strategy is key for both objectives, is long term in nature, and avoids narrowly defined niches. It seems that starting broad based and narrowing down, perhaps to a niche, only at a later stage when this is clearly the appropriate thing to do, pays dividends. [source] Tropical Montane Forest Restoration in Costa Rica: Overcoming Barriers to Dispersal and EstablishmentRESTORATION ECOLOGY, Issue 4 2000Karen D. Holl Abstract Tropical forests are being cleared at an alarming rate although our understanding of their ecology is limited. It is therefore essential to design restoration experiments that both further our basic knowledge of tropical ecology and inform management strategies to facilitate recovery of these ecosystems. Here we synthesize the results of research on tropical montane forest recovery in abandoned pasture in Costa Rica to address the following questions: (1) What factors limit tropical forest recovery in abandoned pasture? and (2) How can we use this information to design strategies to facilitate ecosystem recovery? Our results indicate that a number of factors impede tropical forest recovery in abandoned pasture land. The most important barriers are lack of dispersal of forest seeds and seedling competition with pasture grasses. High seed predation, low seed germination, lack of nutrients, high light intensity, and rabbit herbivory also affect recovery. Successful strategies to facilitate recovery in abandoned pastures must simultaneously overcome numerous obstacles. Our research shows that establishment of woody species, either native tree seedlings or early-successional shrubs, can be successful in facilitating recovery, by enhancing seed dispersal and shading out pasture grasses. On the contrary, bird perching structures alone are not an effective strategy, because they only serve to enhance seed dispersal but do not reduce grass cover. Remnant pasture trees can serve as foci of natural recovery and may enhance growth of planted seedlings. Our results highlight the importance of: (1) understanding the basic biology of an ecosystem to design effective restoration strategies; (2) comparing results across a range of sites to determine which restoration strategies are most generally useful; and (3) considering where best to allocate efforts in large-scale restoration projects. [source] From renewable energy to fire risk reduction: a synthesis of biomass harvesting and utilization case studies in US forestsGCB BIOENERGY, Issue 3 2009A. M. EVANS Abstract The volatile costs of fossil fuels, concerns about the associated greenhouse gas emissions from these fuels, and the threat of catastrophic wildfires in western North America have resulted in increased interest and activity in the removal and use of woody biomass from forests. However, significant economic and logistical challenges lie between the forests and the consumers of woody biomass. In this study, we provide a current snapshot of how biomass is being removed from forests and used across the United States to demonstrate the wide variety of successful strategies, funding sources, harvesting operations, utilization outlets, and silvicultural prescriptions. Through an analysis of 45 case studies, we identified three themes that consistently frame each biomass removal and utilization operation: management objectives, ecology, and economics. The variety and combination of project objectives exemplified by the case studies means biomass removals are complex and difficult to categorize for analysis. However, the combination of objectives allows projects to take advantage of unique opportunities such as multiple funding sources and multiparty collaboration. The case studies also provide insight into the importance of ecological considerations in biomass removal both because of the opportunity for forest restoration and the risk of site degradation. The national view of the economic aspects of biomass removal provided by this wide variety of case studies includes price and cost ranges. This study is an important first step that helps define woody biomass removals which are becoming an essential part of forestry in the 21st century. [source] Some successful strategies for disclosure: What do i say?JOURNAL OF HEALTHCARE RISK MANAGEMENT, Issue 3 2003Communicating intended or unanticipated outcomes in obstetrics. No abstract is available for this article. [source] Voluntary turnover among nurses working in Kuwaiti hospitalsJOURNAL OF NURSING MANAGEMENT, Issue 3 2008MUHAMMAD ALOTAIBI BSN Background, Voluntary turnover rates are high among staff nurses working in Kuwaiti hospitals. It is a major problem, costly and it is presumed to impact on the quality of nursing care delivered. Aims, The two aims of this study were to (1) find out if nurses' resignations in Kuwaiti hospitals could be ascribed to failure in the recruitment process and (2) examine the feelings of nurses who resigned. Methods, Two sets of exit interviews with 60 nurses who had resigned were conducted. Results, No evidence emerged that any false information or misleading information was provided except for the salary adjustments. The real insight lay in what might not have been said in the recruitment interviews. While feelings of discontent emerged in the interviews relating to the loss of income, the greatest source of complaint related to the failure of managers to solve the evident problems. Conclusions, High rates of voluntary turnover require more attention from administrators and policy makers because of its potential consequences in terms of the quality of nursing care delivered. Implications for nursing management, This paper identifies many causes of nurses' voluntary turnover. It also shows the need for nursing managers to explore these causes and suggests successful strategies for recruitment and retention practices and policies. [source] Leadership in Nursing InformaticsJOURNAL OF OBSTETRIC, GYNECOLOGIC & NEONATAL NURSING, Issue 3 2004Patricia Robin McCartney RNC Nursing informatics is a 21st century science with great potential for improving the quality, safety, and efficiency of health care. Perinatal, neonatal, and women's health nurses have an opportunity to contribute and lead in informatics. Leaders must learn about current informatics issues from essential resources, including the literature, professional organizations, and education programs, to develop successful strategies for innovation, collaboration, and implementation. Most important, nurses must be accountable for humanizing the use of technology using a nursing model. [source] Preparing teachers to create a mainstream science classroom conducive to the needs of English-language learners: A feminist action research projectJOURNAL OF RESEARCH IN SCIENCE TEACHING, Issue 9 2005Gayle Buck A feminist action research team, which consisted of a science educator, an English-language learner (ELL) educator, a first-year science teacher, and a graduate assistant, set a goal to work together to explore the process a beginning teacher goes through to establish a classroom conducive to the needs of middle-level ELL learners. The guiding questions of the study were answered by gathering a wealth of data over the course of 5 months and taken from the classroom, planning sessions, and researchers and students. These data were collected by observations, semistructured interviews, and written document reviews. The progressive analysis ultimately revealed that: (a) successful strategies a beginning teacher must utilize for teaching middle-level ELL children in a mainstream classroom involve complex structural considerations that are not part of the teacher's preparation; (b) learning increases for all children, but there are differences in learning achievement between ELL and non-ELL children; and (c) student and peer feedback proved to be an effective means of enhancing the growth of a beginning teacher seeking to increase her skills in teaching ELL learners. The experiences and findings from this project have implications for teacher preparation programs committed to preparing educators to teach science to all children. © 2005 Wiley Periodicals, Inc. J Res Sci Teach 42: 1013,1031, 2005 [source] Somatic Embryogenesis in Leguminous PlantsPLANT BIOLOGY, Issue 2 2000P. Lakshmanan Abstract: This review examines recent advances in the induction and development of somatic embryos in leguminous plants. Emphasis has been given to identify the current trends and successful strategies for the establishment of somatic embryogenic systems, particularly in the economically important species. It appears that, in legumes, somatic embryogenesis can be realized relatively easily especially in young meristematic tissues such as immature embryos and developing leaves. In the majority of the species examined, chlorophenoxyacetic acids remained the most active inductive compounds; however, the new generation growth regulators such as thidiazuron are emerging as successful alternatives for high-frequency direct regeneration of somatic embryos, even from well differentiated explant tissues. Low-frequency embryo production, poor germination and conversion of somatic embryos into plantlets and somaclonal variation are the major impediments limiting the utility of somatic embryogenesis for biotechnological applications in legumes. These limitations, however, may be considerably reduced in the near future, as more newly developed growth regulators with specific morphogenic targets become available for experimentation. From the published data, it is apparent that more effort should be given to develop repetitive embryogenic systems with high frequency of germination and regeneration, since such systems will find immediate application in mass propagation and other crop improvement programmes. As our understanding of various morphogenic processes, including growth and differentiation of zygotic embryos, is fast expanding, it is conceivable that development of highly efficient somatic embryogenic systems with practical application can be anticipated, at least for the important leguminous crops, in the foreseeable future. [source] Learning to Cooperate: Learning Networks and the Problem of AltruismAMERICAN JOURNAL OF POLITICAL SCIENCE, Issue 3 2009John T. Scholz We explore how two populations learn to cooperate with each other in the absence of institutional support. Individuals play iterated prisoner's dilemmas with the other population, but learn about successful strategies from their own population. Our agent-based evolutionary models reconfirm that cooperation can emerge rapidly as long as payoffs provide a selective advantage for nice, retaliatory strategies like tit-for-tat, although attainable levels of cooperation are limited by the persistence of nonretaliatory altruists. Learning processes that adopt the current best response strategy do well only when initial conditions are very favorable to cooperation, while more adaptive learning processes can achieve high levels of cooperation under a wider range of initial conditions. When combined with adaptive learning, populations having larger, better connected learning relationships outperform populations with smaller, less connected ones. Clustered relationships can also enhance cooperation, particularly in these smaller, less connected populations. [source] Context and its significance in identifying ,what works' in child protectionCHILD ABUSE REVIEW, Issue 3 2005Adrian Barton Abstract The repetitive nature of the underlying problems with child protection systems identified by many inquiries into child deaths suggests that the ability to transpose successful strategies from one area to another may be contingent on more than a ,technical' approach to best practice. Current policy responses to failing child protection systems are arguably based on an assumption that practices that work in one area may be applied in other areas without reference to the existing base for practice. Drawing on our own experiences in the field, we attempt to explore some methodological issues relevant to the evaluation of service provision and the dissemination of effective practice in interagency working. Copyright © 2005 John Wiley & Sons, Ltd. [source] A software player for providing hints in problem-based learning according to a new specificationCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 3 2009Pedro J. Muñoz-Merino Abstract The provision of hints during problem solving has been a successful strategy in the learning process. There exist several computer systems that provide hints to students during problem solving, covering some specific issues of hinting. This article presents a novel software player module for providing hints in problem-based learning. We have implemented it into the XTutor Intelligent Tutoring System using its XDOC extension mechanism and the Python programming language. This player includes some of the functionalities that are present in different state-of-the-art systems, and also other new relevant functionalities based on our own ideas and teaching experience. The article explains each feature for providing hints and it also gives a pedagogical justification or explanation. We have created an XML binding, so any combination of the model hints functionalities can be expressed as an XML instance, enabling interoperability and reusability. The implemented player tool together with the XTutor server-side XDOC processor can interpret and run XML files according to this newly defined hints specification. Finally, the article presents several running examples of use of the tool, the subjects where it is in use, and results that lead to the conclusion of the positive impact of this hints tool in the learning process based on quantitative and qualitative analysis. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 17: 272,284, 2009; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20240 [source] Affordable diagnostics,Changing the paradigm in India,,CYTOMETRY, Issue S1 2008Bala S. Manian Abstract A successful strategy for developing affordable diagnostics begins with a shift in viewpoint. Diagnostics is a tool for generating clinical information. Amassed experience in different parts of the globe has shown that this process of generating and utilizing clinical information is not only different among various countries but also different in microenvironments within the same country. The development of affordable diagnostics requires consideration not only of the component costs such as hardware and consumables but also other related costs that contribute to the generation and delivery of that information. It is important to recognize that these costs associated with public health in resource-poor settings cannot remain at the mercy of charitable contributions from western nations. Therefore, the challenge of technological innovation is to create solutions that are locally affordable and sustainable in the long run within the local macroeconomic constraints. The solutions should permit generation of local economic activity that will reinforce long-term economic sustainability. For this reason it is essential not only to analyze the diagnostic process but also to define a pathway by which local healthcare systems in recipient nations can be endowed with elements that empower them to acquire and practice up-to-date modern diagnostic skills. The objective of this paper is to provide a wider view of diagnostic cost components and to show how solutions developed and delivered locally have resulted in economically affordable as well as sustainable products. © 2008 Clinical Cytometry Society [source] Successful Treatment of Dowling,Degos Disease with Er:YAG LaserDERMATOLOGIC SURGERY, Issue 8 2002Joerg Wenzel MD background. Dowling,Degos disease is a rare condition with a genetically determined disturbance of epidermal proliferation. The typical clinical picture is a reticulate pigmentation of the flexures, genital folds, and pectoral skin areas. Many different treatment options have been tried in recent years without a convincing therapeutic benefit. objective. To determine the effectiveness of Er:YAG laser in Dowling-Degos disease. methods. A 44-year-old woman suffering from Dowling-Degos disease was treated with the Er:YAG laser pulse energy between 1,000 and 1,200 mJ, three consecutive passes. results. The laser treatment led to a good clinical result. conclusion. Our case suggest that treatment with the Er:YAG laser might be a successful strategy in Dowling-Degos disease. [source] Inclusive Design in Apparel Product Development for Working Women With Physical DisabilitiesFAMILY & CONSUMER SCIENCES RESEARCH JOURNAL, Issue 4 2007Kate E. Carroll Consumers with physical limitations want apparel products and retail environments that work for them. Inclusive design is a framework for developing products to satisfy multiple consumers, regardless of their physical ability. This qualitative study reports on physical limitations and apparel preferences of working women (n = 9) with a variety of limitations. A prototype for a garment was developed, wear-tested, and evaluated using inclusive design criteria. Subsequently, manufacturers (n = 6) were interviewed regarding production and distribution within the existing system. Results indicate that (a) the effect of disability on the body supercedes clinical definition for apparel product development, (b) working women with various disabilities have similar apparel needs, (c) inclusive design can be a successful strategy for product development, and (d) current industry perceptions about disability present the greatest barrier to successful implementation. The researchers conclude that further studies should focus on industry "buy-in" of inclusive design as a framework for product development. [source] A functional hypothesis for adult hippocampal neurogenesis: Avoidance of catastrophic interference in the dentate gyrusHIPPOCAMPUS, Issue 3 2006Laurenz Wiskott Abstract The dentate gyrus is part of the hippocampal memory system and special in that it generates new neurons throughout life. Here we discuss the question of what the functional role of these new neurons might be. Our hypothesis is that they help the dentate gyrus to avoid the problem of catastrophic interference when adapting to new environments. We assume that old neurons are rather stable and preserve an optimal encoding learned for known environments while new neurons are plastic to adapt to those features that are qualitatively new in a new environment. A simple network simulation demonstrates that adding new plastic neurons is indeed a successful strategy for adaptation without catastrophic interference. © 2006 Wiley-Liss, Inc. [source] Town centre management schemes in the UK: marketing and performance indicatorsINTERNATIONAL JOURNAL OF NONPROFIT & VOLUNTARY SECTOR MARKETING, Issue 4 2004Sophie Hogg While town centre management (TCM) has proved to be a successful strategy to maintain, improve and regenerate town centres through local partnership, there has been relatively little attention drawn to the marketing of TCM schemes. This paper explores the issues surrounding the use of key performance indicators (KPIs) for the marketing of TCM schemes in the context of wider place marketing activities undertaken by towns and cities. Drawing on evidence from a questionnaire survey of town centre managers, it is posited that they might usefully employ carefully selected KPI data to maintain and attract private investment to TCM schemes from internal and external town centre stakeholders. The paper then introduces a typology for the use of KPI marketing in town centre management. Copyright © 2004 Henry Stewart Publications [source] Aerobic biological treatment of waste- waters containing dichloromethaneJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 9 2007Sandra C Moura Abstract BACKGROUND: Volatilization has been advanced as one of the predominant phenomena contributing to volatile organic carbon emissions from wastewater treatment plants (WWTPs). In this study, strategies for minimizing such air stripping losses when treating a liquid stream containing dichloromethane (DCM), aiming at decreasing the overall emission inventory from WWTPs, were investigated. RESULTS: System R1, consisting of a continuous flow stirred tank reactor (CSTR) treating a liquid stream containing DCM at a concentration of 12 mmol dm,3 presented a biodegradation efficiency (BE) of 68%, based upon chloride release, with 10% of measurable losses, mainly due to volatilization, and 22% of unmeasurable losses. System R2 introduced operational designs aiming at decreasing DCM volatilization. In Experiment R2.1, a biotrickling filter, through which the air stripped from the CSTR was driven, was introduced leading to a reduction from 10% to 7% on the measurable losses. In Experiment R2.2, the air stripped from the CSTR was recirculated at a flow rate of 2.4 dm3 h,1 through the reactor medium before entering the biotrickling filter. The BE was improved from 69% to 82% and the losses associated with air stripping were successfully reduced to 2%. The proposed design, including air recirculation and the biotrickling filter, increased the ratio between the biodegradation rate and the volatilization rate from 7 to 41. CONCLUSIONS: Recirculation of the gaseous effluent through the reactor medium, which allowed for higher residence time within the bioreactor, was shown to be a successful strategy for improving the treatment process, thus minimizing DCM volatilization losses. Copyright © 2007 Society of Chemical Industry [source] Modernizing UK health services: ,short-sharp-shock' reform, the NHS subsistence economy, and the spectre of health care famineJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 2 2005Bruce G. Charlton MD Abstract Modernization is the trend for societies to grow functionally more complex, efficient and productive. Modernization usually occurs by increased specialization of function (e.g. division of labour, such as the proliferation of specialists, in, medicine),, combined, with, increased, organization, in, order to co-ordinate the numerous specialized functions (e.g. the increased size of hospitals and specialist teams, including the management of these large groups). There have been many attempts to modernize the National Health Service (NHS) over recent decades, but it seems that none have significantly enhanced either the efficiency or output of the health care system. The reason may be that reforms have been applied as a ,drip-drip' of central regulation, with the consequence that health care has become increasingly dominated by the political system. In contrast, a ,short-sharp-shock' of radical and rapid modernization seems to be a more successful strategy for reforming social systems , in-between waves of structural change the system is left to re-orientate towards its client group. An example was the Flexner-initiated reform of US medical education which resulted in the closure of nearly half the medical colleges, an immediate enhancement in quality and efficiency of the system and future growth based on best institutional practices. However, short-sharp-shock reforms would probably initiate an NHS ,health care famine' with acute shortages and a health care crisis, because the NHS constitutes a ,subsistence economy' without any significant surplus of health services. The UK health care system must grow to generate a surplus before it can adequately be modernized. Efficient and rapid growth in health services could most easily be generated by stimulating provision outside the NHS, using mainly staff trained abroad and needs-subsidized ,item-of-service'-type payment schemes. Once there is a surplus of critically vital health services (e.g. acute and emergency provision), then radical modernization should rapidly improve the health service by a cull of low-quality and inefficient health care providers. [source] Evolution of sexual size monomorphism: the influence of passive mate guardingJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 7 2009A. E. DUNHAM Abstract Some species have potential for intense mate competition yet exhibit little or no sexual size dimorphism, despite predictions from sexual selection theory. Using a conceptual model, we show the conditions for which passive mate guarding with copulatory plugs can be an alternative and more successful strategy to active (direct) guarding, reducing selection pressure on large male size. The model predicts that copulatory plugs in mammals should be favoured in species for which females have short sexual receptivity periods. Using data on 62 primate species and a phylogenetic regression approach, we show that, as predicted, copulatory plugs are negatively associated with degree of sexual dimorphism and females' sexual receptivity length. Penile spines are also significantly associated with plug use and short receptivity periods suggesting a possible offensive role in sperm competition. Results highlight that life-history characteristics, such as sexual receptivity lengths, may alter the costs and benefits of alternative male strategies and thus alter the strength of sexual selection. [source] Clinical Practice: An Emphasis Strategy for Promotion and TenureNURSING FORUM, Issue 4 2003Linda S. Paskiewicz RN TOPIC Emphasizing clinical practice in promotion and tenure materials. PURPOSE To share a successful strategy centered on clinical practice with members of the tenure track, advanced practice nurse faculty. SOURCES Published literature, author's experience. CONCLUSIONS Creativity and planning can assist tenure track faculty members in emphasizing their clinical practice for promotion and tenure. Recognition and rewards for clinical practice beyond the school of nursing continue to be challenges in the larger university. [source] Relationships between the genetic distance of Epichloë festucae isolates and the ergovaline and peramine contents of their Festuca rubra hostsANNALS OF APPLIED BIOLOGY, Issue 1 2010B.R. Vázquez-de-Aldana In semiarid grasslands of western Spain, plants of Festuca rubra are frequently infected by Epichloë festucae, an endophyte capable of producing the alkaloids ergovaline, toxic to mammals, and peramine, toxic to insects. The objectives of this paper were to estimate the variability in the content of ergovaline and peramine in plants of Festuca rubra from natural populations and to determine the relationship between the genetic distance among Epichloë strains and the alkaloid contents of plants infected by them. The results showed that a significant variation exits in the ergovaline and peramine contents of infected F. rubra plants, and that variation patterns are different for each alkaloid. Ergovaline content showed a significant variation between years. In contrast, most variation observed in the concentration of peramine occurred between populations. Mantel tests, constrained correspondence analysis (CCA) and generalised analysis of molecular variance (GAMOVA) all revealed a significant relationship between the genetic distances among 35 Epichloë isolates, and the differences in peramine content of their host plants. The relationship observed for ergovaline was more ambiguous. This indicates that plants infected by genetically close isolates of Epichloë festucae tend to be similar in terms of peramine content, while the ergovaline content of infected plants seems to be more dependent on external factors. The results of this study suggest that the selection of Epichloë festucae endophytes based on the alkaloid content of their host plants can be a successful strategy to select good or bad producers of peramine, but may not be a reliable method to detect fungal strains associated with particular ergovaline production profiles. [source] Dilemmas of Policy Innovation in the Public Sector: A Case Study of the National Innovation SummitAUSTRALIAN JOURNAL OF PUBLIC ADMINISTRATION, Issue 4 2009Ian Marsh Policy innovation is a significant challenge for the public sector. This article illustrates its magnitude through a case study of the National Innovation Summit. The article concludes that the Summit represented an elaborate process of search and engagement that sanctioned an outcome that was, in most respects, largely pre-determined. Its outreach and deliberations served the political purpose of mobilising industry and media attention and communicating the government's commitment. But there is no evidence that it exercised any substantive influence on policy development. The obstacles confounding any other outcome are considerable. Strategic thinking is inhibited by various organisational factors including lock-in to a present successful strategy, the constraints on policy choices associated with multiple veto points and the need to maintain medium term fiscal and policy discipline across a wide range of agencies and claimants. The article explores ways these inhibitions might be overcome. [source] A Novel Genetic Selection System for Improved Enantioselectivity of Bacillus subtilis Lipase ACHEMBIOCHEM, Issue 7 2008Ykelien L. Boersma Dr. Abstract In directed evolution experiments, success often depends on the efficacy of screening or selection methods. Genetic selections have proven to be extremely valuable for evolving enzymes with improved catalytic activity, improved stability, or with altered substrate specificity. In contrast, enantioselectivity is a difficult parameter to select for. In this study, we present a successful strategy that not only selects for catalytic activity, but for the first time also for enantioselectivity, as demonstrated by the selection of Bacillus subtilis lipase A variants with inverted and improved enantioselectivity. A lipase mutant library in an aspartate auxotroph Escherichia coli was plated on minimal medium that was supplemented with the aspartate ester of the desired enantiomer (S)-(+)-1,2- O -isopropylidene- sn -glycerol. To inhibit growth of less enantioselective variants, a covalently binding phosphonate ester of the opposite (R)-(,)-1,2- O -isopropylidene- sn -glycerol enantiomer was added as well. After three selection rounds in which the selection pressure was increased by raising the phosphonate ester concentration, a mutant was selected with an improved enantioselectivity increased from an ee of ,29.6,% (conversion 23.4,%) to an ee of +73.1,% (conversion 28.9,%) towards the (S)-(+)-enantiomer. Interestingly, its amino acid sequence showed that the acid of the catalytic triad had migrated to a position further along the loop that connects ,7 and ,E; this shows that the position of the catalytic acid is not necessarily conserved in this lipase. [source] | |||||||||||||||||||||||||