Science and Business

There are two kinds of scientists in evolutionary studies that need a space of debate:  the specialists in evolutionary studies in business and all other evolutionary scientists in general. The themes of the discussion are the behaviour, growth, reproduction, and organizational structures of the firm

Use of clickbait in the online news media of the 28 EU member countries

This article offers an analysis of “clickbait”, one of the latest strategies employed by online news media to lure users into clicking a hyperlink through the use of non-journalistic values. Methods. The study is based on the analysis of the news headlines found on the front and inner pages of general-information newspapers of the 28 EU member countries. Results. The main consequence of the use of clickbait is that the news headline has gone from being just a key element to provide information to also crucial element to persuade the reader to stay on the page for as long as possible. Discussion. The results confirm the presence of clickbait in most of the newspapers analysed, to the detriment of traditional journalistic values in the writing and editing of headlines. Conclusions. The study concludes that general-information newspapers in the 28 EU member countries generate clicks not through quality content but rather, in nearly half the cases, through catchy, provocative and sensationalist front-page headlines that aim to exploit the curiosity in usersThis article was developed within the framework of the research project titled “Informative uses and preferences on the new media landscape in Spain: journalism models for mobile devices” (Reference: CSO2015-64662-C4-4-R), funded by the Spanish Ministry of Economy and CompetitivenessS

Characterization of the catalytic flexible loop in the dihydroorotase domain of the human multi-enzymatic protein CAD

The dihydroorotase (DHOase) domain of the multifunctional protein carbamoyl-phosphate synthetase 2, aspartate transcarbamoylase, and dihydroorotase (CAD) catalyzes the third step in the de novo biosynthesis of pyrimidine nucleotides in animals. The crystal structure of the DHOase domain of human CAD (huDHOase) revealed that, despite evolutionary divergence, its active site components are highly conserved with those in bacterial DHOases, encoded as monofunctional enzymes. An important element for catalysis, conserved from Escherichia coli to humans, is a flexible loop that closes as a lid over the active site. Here, we combined mutagenic, structural, biochemical, and molecular dynamics analyses to characterize the function of the flexible loop in the activity of CAD's DHOase domain. A huDHOase chimera bearing the E. coli DHOase flexible loop was inactive, suggesting the presence of distinctive elements in the flexible loop of huDHOase that cannot be replaced by the bacterial sequence. We pinpointed Phe-1563, a residue absolutely conserved at the tip of the flexible loop in CAD's DHOase domain, as a critical element for the conformational equilibrium between the two catalytic states of the protein. Substitutions of Phe-1563 with Ala, Leu, or Thr prevented the closure of the flexible loop and inactivated the protein, whereas substitution with Tyr enhanced the interactions of the loop in the closed position and reduced fluctuations and the reaction rate. Our results confirm the importance of the flexible loop in CAD's DHOase domain and explain the key role of Phe-1563 in configuring the active site and in promoting substrate strain and catalysi