pH-Dependent Capping Interactions Induce Large-Scale Structural Transitions in i-Motifs

We study here a DNA oligonucleotide having the ability to form two different i-motif structures whose relative stability depends on pH and temperature. The major species at neutral pH is stabilized by two C:C+ base pairs capped by two minor groove G:C:G:C tetrads. The high pH and thermal stability of this structure are mainly due to the favorable effect of the minor groove tetrads on their adjacent positively charged C:C+ base pairs. At pH 5, we observe a more elongated i-motif structure consisting of four C:C+ base pairs capped by two G:T:G:T tetrads. Molecular dynamics calculations show that the conformational transition between the two structures is driven by the protonation state of key cytosines. In spite of large conformational differences, the transition between the acidic and neutral structures can occur without unfolding of the i-motif. These results represent the first case of a conformational switch between two different i-motif structures and illustrate the dramatic pH-dependent plasticity of this fascinating DNA motif

The use of internal audits as a tool to analyze skills and competences

[EN] The degrees of the faculty of Chemistry of the University of Barcelona have implemented a quality management system (QMS) (Real Decreto 1393/2007; Real Decreto 861/2010). One of the common subjects taught in formative period of the students is Quality and Prevention. The competences that the students must acquire are knowing the QMS and the basis of certification and accreditation. They must also have skills to plan and propose actions to ensure quality and to prepare documentation of a quality management system, among others. The aim of the work is the execution of internal audits carried out by students to analyze the degree of skills and competences obtained by the auditors throughout the course Quality and Prevention.Fernandez, J.; Cruells, M.; Escaja, N.; Garrido, JA.; Giménez, J.; Llauradó, M.; Roca, A.... (2016). The use of internal audits as a tool to analyze skills and competences. En 2nd. International conference on higher education advances (HEAD'16). Editorial Universitat Politècnica de València. 196-202. https://doi.org/10.4995/HEAD16.2015.2647OCS19620

pH-induced structural transitions in mini i-motifs.

International Symposium BIONIC 2018 BIOLOGY OF NON-CANONICAL NUCLEIC ACIDS: from humans to pathogens. 26- 28 SEPTEMBER 2018. Event location: BOTANICAL GARDEN, ​Padua, ITAL

Conformational transitions in non canonical DNA structures

Joint 12th EBSA congress / 10th ICBP – IUPAP congress: Biophysics for life and technology, Madrid, Spain, July 20Ǧ24, 2019. -- http://www.ebsa2019.org/ . -- European Biophysics Journal (2019) 48 (Suppl 1):S1–S26