The knockdown of eIF4AI interferes with the respiratory syncytial virus replication cycle.

The respiratory syncytial virus (RSV) is one of the main etiological agents in acute respiratory infections. To date, the replicative cycle of this virus is not completely known, and the events as well as the role of cellular and viral proteins that participate in the infectious cycle of RSV are still a matter of intense research. An important protein that is a control point for many viruses is the helicase eIF4AI, which participates at the beginning of the cap-dependent translation of eukaryotes and cap-independent translation of certain viral mRNAs. Recently, eIF4AI has been considered as a potential viral therapeutic target. In order to understand the role of eIF4AI during the infectious cycle of RSV, we evaluated the effect of eIF4AI knockdown on the amount of positive-strand viral RNA and viral progeny of this virus. Our results showed a decrease for both parameters, suggesting a possible involvement of eIF4AI during replicative cycle of RSV. In addition, using confocal microscopy, it was observed that eIF4AI colocalized with RSV viral protein, supporting the possible participation of eIF4AI during the replicative cycle of RSV. Keywords: eIF4AI; RSV; translation; antiviral.

A bacterial strain of Pseudomonas aeruginosa B0406 pathogen opportunistic, produce a biosurfactant with tolerance to changes of pH, salinity and temperature.

A bacterial strain of Pseudomonas aeruginosa B0406 catalogued as pathogen opportunistic was capable to grow with waste cooking oil as only carbon source and produce a biosurfactant. Stability to pH (from 2 to 12), salinity (% NaCl from 0 to 20%) and temperature (from -20 °C up to 120 °C), of biosurfactants was evaluated using a response surface methodology. Biosurfactants reduced surface tension from 50 to 29 ± 1.0 mN/m. Pseudomonas aeruginosa B0406 showed a high biosurfactant yield 4.17 g/L ± 0.38. Biosurfactants stability applying a response surface methodology was observed with combining effect of pH, salinity and temperature. The three factors combined do not affect surface tension of biosurfactants produced by Pseudomonas aeruginosa B0406. Therefore, this biosurfactants are of interest for medical, cosmetic even environmental applications.