Xylan-binding xylanase Xyl30 from Streptomyces avermitilis: cloning, characterization, and overproduction in solid-state fermentation

A DNA fragment from the lignocellulolytic actinomycete Streptomyces avermitilis CECT 3339 was cloned using a DNA probe from the xylanase gene xysA of Streptomyces halstedii. The nucleotide sequence analysis revealed two potential ORFs, xyl30 and hd30, encoding a deduced multimodular F/10 xylanase with a binding domain and a secreted glycoxyl hydrolase, respectively. In Streptomyces lividans carrying the subcloned DNA fragment, two xylanase activity bands with estimated molecular masses of 42.8 and 35 kDa (named Xyl30 forms "h" and "l", respectively), were detected by zymograms and SDS-PAGE. The two xylanases had identical N-terminal sequences, suggesting that Xyl30 "l" derived from Xyl30 "h" by C-terminal processing in the culture supernatant. No transcripts of hd30 were detected by RT-PCR. Characterization of the partially purified Xyl30 "h" confirmed the presence of a modular endoxylanase containing a xylan-binding domain, which after processing in the culture supernatant loses the aforementioned domain and thus its capacity to bind xylan (Xyl30 "l"). Xyl30 "h" achieved maximal activity at pH 7.5 and 60 degrees C, retaining more than 50% of its activity from pH 3 to 9 and more than 40% after a 1-h incubation at 70 masculineC. Moreover, in the recombinant host strain up to 400 U xylanase/g medium (dry weight) was produced in solid-state fermentation (SSF) using cereal bran as substrate. The high production yields of this enzyme and its biochemical features make it a good candidate for use in industrial applications

Strategies for penicillin V dendronization with cationic carbosilane dendrons and study of antibacterial properties.

Strategies to synthesize a cationic carbosilane dendron containing the antibiotic penicillin V potassium salt (PenVK) at the focal point are discussed. The preparation of such a compound requires the use of systems with no donor atoms such as N or S in their framework, because their presence favours the rupture of the penicillin beta-lactam ring. The antibacterial activity of the new dendron containing ammonium groups, at the periphery, and the PenV moiety, at the focal point, against gram-positive Staphylococcus aureus strains was evaluated. These results were compared with those obtained for free PenVK, a related cationic dendron without a penicillin moiety at the focal point, and also compared with an equimolar mixture of this last dendron with free PenV. The data obtained indicate that, on one hand, the conjugation or interaction of PenV with cationic dendrons reduces its activity in comparison with free PenVK. On the other hand, the penicillin dendron is able to release the antibiotic in the presence of esterease, due to the breaking of the ester bond in this derivative.Ministerio de Economía y Empres

Guided weekly reflection papers: a strategy for Achieving academic goals

Rapid changes in innovative teaching need multidisciplinary efforts to accomplish a variety of goals through a collaborative tool which inspires and stimulates the students to learn and use the knowledge in a more a critical way. In this context, our team of lecturers concerned by educational innovation had carried out during three academic years a learning tool based on “Weekly Reflection Papers” (WRP). With the experience gained in this process we have implemented an essential modification in the procedure in order to improve the teaching-learning process. The goal of this communication is to show the development of the initial tool and how it has been changed until the actual proposal called Guided Weekly Reflection Papers” (GWRP)

Improving learning environment at different academic Levels throughout guided weekly reflection papers

A group of lecturers from different teaching areas at Alcalá University concern by Innovative Education had implemented during four academic years a learning tool based on “reflective weekly papers”. With the experience gained in this process we have carried out an essential modification in the procedure which provides the students the possibility of a more active and participative learning called Guided Weekly Reflective Papers. In this communication we present the adaptation of this educational method for the first time as a valuable strategy for improving the learning environment in secondary schools, as an extension of its implementation at the University level and as a contribution to the integral formation and meaningful learning of the secondary level students

Guided Weekly Reflection Papers

The experience gained by our team of educational innovation with the implementation of the “Weekly Reflection Papers” has led us to diversify and make more flexible the employed methodology. The modified tool, applied during the academic year 2010-2011, was called “Guided Weekly Reflection Papers”. The aim of this modification has been the development of certain abilities and skills of the students, with particular emphasis on their ability to integrate, review and apply knowledge in a critical and reflective way. The professors guide the student´s work through a series of questions on which the students must apply the most significant concepts studied each week, to prove the acquisition of such aptitudes and skills

An information literacy approach within the "Guided weekly reflection papers"

INTED 2015, 9 th International Technology, Education and Development Conference, March 2 nd-4 th, 2015-Madrid, SpainA group of lecturers from diverse areas of knowledge of the University of Alcalá have implemented an experience of teaching innovation based on “reflective diaries”. The students hand in to the lecturer every week their “Weekly Reflection Papers” (WRP), in which they schematically express the most important ideas related with the topic presented during the classes of the previous week. They must include their reflections about the aspects they found especially interesting. After having applied this tool for some academic years we introduced a modification called “Guided Weekly Reflection Papers” (GWRP), where the professors suggest a series of questions on which the students must apply the most significant concepts studied each week. This modification enhances student’s motivation, encourages them to achieve more significant and reflective knowledge and generates interest in emergent topics. However, we often detect that the information management needed to solve the proposed questions in the GWRP is not the most suitable one. Therefore our present work is aimed at helping students develop the necessary skills and acquire a searching criterion in the framework of the information literacy. The strategy was focussed on some important items for the acquisition of information competencies. In this communication we analyze the progress of the GWRP tool and we explore the response of students to the information literacy approach

Guided Weekly Reflection Papers

The experience gained by our team of educational innovation with the implementation of the “Weekly Reflection Papers” has led us to diversify and make more flexible the employed methodology. The modified tool, applied during the academic year 2010-2011, was called “Guided Weekly Reflection Papers”. The aim of this modification has been the development of certain abilities and skills of the students, with particular emphasis on their ability to integrate, review and apply knowledge in a critical and reflective way. The professors guide the student´s work through a series of questions on which the students must apply the most significant concepts studied each week, to prove the acquisition of such aptitudes and skills

Structure-activity relationship study of cationic carbosilane dendritic systems as antibacterial agents

This work focuses on the antibacterial activity against Gram-positive Staphylococcus aureus and Gramnegative Escherichia coli and the hemolytic properties of two types of ammonium cationic carbosilane systems: dendrimers and dendrons. The effects of: i) the generation, ii) the type of peripheral groups near the cationic charges (a SiMe2 moiety or a S atom depending on the synthetic procedure, hydrosilylation or thiol-ene addition, respectively), iii) the core of dendrimers (polyphenoxo vs. Si atom) and iv) the focal point of dendrons (-N3, -NH2, -OH) have been assessed. The structure-activity relationship analysis indicates the importance of an adequate balance between the hydrophilic and lipophilic fragments of these molecules to reach the best antibacterial activity. Regarding hemolysis, lowest toxicity values were registered for dendritic systems with a sulfur atom close to the surface and, in the particular case of dendrons, for those with a hydroxyl focal point. One dendrimer and one dendron, both bearing a sulfur atom close to the surface, scored best in the activity-toxicity relationship analysis and were chosen for resistance assays. No changes in the inhibitory and bactericidal capacity in the case of the dendron and only a slight increase of these values for the dendrimer were observed after 15 subculture cycles. Furthermore, these two compounds stayed active towards different strains of resistant bacteria and avoid formation of biofilm at concentrations over the minimum inhibitory concentration (MIC).Ministerio de Economía y Empres

Reflective practice applications: "Guided weekly refection papers" excented from Alcalá University (Spain) to the Montfort University (UK)

Edulearn16: 8th International Conference on Education and New Learning Technologies. Barcelona, 4th-6th of july, 2016-Barcelona, SpainKnowledge has to be developed firmly based on reflections and thoughts as much as evidence. Being conscious of this principle, our innovation teaching group from the University of Alcalá has developed a reflective pedagogical approach called Guided Weekly Reflection Papers (GWRP) and implemented it since 2007. In this approach students hand in to the lecturer their “weekly work”, in which they schematically express the most important ideas related with the topic presented during the classes, and their reflections and comments on those aspects which they found especially difficult or interesting. Moreover students have to apply the concepts developed during the week to solve some questions or problems proposed by the lecturers to find solutions to real life situations and to explore beyond the walls of the classroom to discover where in the world around them they can find application of the material presented by the lectures.This innovative pedagogical approach has deeply contributed to the development of the student learning process and consequently been reflected in our teaching practice. The outcomes of the GWRP activity do not depend upon how much students have been studying but upon the level of comprehension of the knowledge we have shared with them. Therefore this strategy is very useful to prove the efficiency and quality of our teaching practice which leads us to continuously improve our way of teaching. Over several years, we have shown our results both in internal meetings in our University and in International Conferences, our colleagues have been caught up by our enthusiasm, which promotes their involvement in our model. Thus, different academics and organizations have adopted our reflective pedagogic strategy. The most recent incorporation of this approach has been implemented by selected academic staff at De Montfort University (DMU), Leicester (United Kingdom). This versatile methodology is being tested in a new university educational environment using a student cohort with a different set of characteristics and academic context compared to previous cohorts. This communication will describe the adaptation of the GWRP to teaching in the Clinical Biochemistry module delivered as part of two different Bachelor degrees taught at DMU: Biomedical Science and Medical Science and the response of students enrolled in this programmes at DMU. The results of the GWRP implemented in new subjects by the teachers of the innovation group at the University of Alcalá (UAH) will be also analysed

Implementación crítica de la reflexión en el proceso de enseñanza-aprendizaje

This communication describes the evolution of an educational innovation strategy, originally called Weekly Reflection Papers, aimed to modify the practical teaching and to go deeper in the process of teaching and learning in higher education. To do this, seven teachers of different subjects of the University of Alcalá have applied this tool to achieve the proposed objectives, essentially based on that students learn to reflect on their own way of learning. Our innovation group has introduced various modifications in this strategy over the years. One of the priorities today is to place a greater emphasis on reflection with what is intended, on the one hand, to teach students to develop their reflective ability and on the other hand it would be very useful for us to analyze in more depth, the educational possibilities that presents this part of the tool. This work includes surveys carried out at the beginning and at the end of each subject, as well as a guide for reflection.En esta comunicación se describe la evolución de una estrategia de innovación educativa, denominada originariamente Semanarios Reflexivos, encaminada a modificar la práctica docente y profundizar en el proceso de enseñanza-aprendizaje en la educación universitaria. Para ello, siete profesores de diferentes asignaturas de la Universidad de Alcalá hemos aplicado esta herramienta para alcanzar los objetivos propuestos, que fundamentalmente se basan en que los alumnos aprendan a reflexionar sobre su propia manera de aprender. Nuestro grupo de innovación ha introducido diferentes modificaciones en dicha estrategia a lo largo de los años. En la actualidad una de las prioridades es hacer un mayor hincapié en la reflexión, con lo que se pretende, por una parte, enseñar a los estudiantes a desarrollar su capacidad reflexiva y, por otra, aprender nosotros mismos a analizar, con más profundidad, las posibilidades docentes que presenta esta parte de la herramienta. Este trabajo incluye unas encuestas que se realizan al principio y al final de cada asignatura, así como una guía para la reflexión