Research

Research

TDP-43TDP-43 is a protein which acts in part like an editor and in part like a postman; he modifies his "messages" written in RNA, before delivering them to the cytoplasm. Under certain "bad weather" conditions, part of the TDP-43 protein acts like an "umbrella" (really a hydrogel or functional amyloid) to protect the messages. But sometimes these "umbrellas" can break and become tangled together, forming a "net" (harmful amyloid aggregates) that disrupts the message editing and delivery system, and putatively leads to cell death. In fact, TDP-43 aggregates are linked to amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease that kills 4000 Spaniards per year. The elucidation by NMR of the structure, dynamics and stability of the first quarter, or N-terminal domain, of the TDP-43 protein's structure, dynamics and stability by NMR methods provides the keys to better understand the function and malfunction of this important protein.

Mompeán M, Romano V, Pantoja-Uceda D, Stuani C, Baralle FE, Buratti E and Laurents DV "The TDP-43 N-Terminal Domain Structure at High Resolution." FEBS J. Jan 12th, 2016
doi: 10.1111/febs.13651

 

Orrego-et-alA new method for connecting the dynamics and function of proteins immobilized on agarose beads is demonstrated. The mobility of proteins was quantified in any location of agarose beads, at different depths (0-100 microns; 500-600 nm spatial resolution), from fluorescence anisotropy optical sections of the beads. Protein fluorescence anisotropy informs about restriction of the global rotation of the immobilized proteins onto a solid surface. A general protein mobility scale was defined, which is independent of instrumental settings and fluorescent probes. Protein mobility is very sensitive to the chemistry of immobilization, as well as to the hydrogel porous microstructure resulting from the immobilization reactions. In this way better immobilization processes may be designed, leading to more stable heterogeneous biocatalysts with interest for the biodiesel and food industries.

Orrego AH, García C, Mancheño JM, Guisán JM, Lillo MP, López-Gallego F
"Two-Photon Fluorescence Anisotropy Imaging to Elucidate the Dynamics and the Stability of Immobilized Proteins" J Phys Chem B (2016) 120, 485-491.
DOI: 10.1021/acs.jpcb.5b12385

 

ozono tropicalTropospheric ozone is an important greenhouse gas. Ozone has exerted an increase in the global radiative forcing of climate almost equal to that of methane over the period between 1750 and 2011. The largest contribution to the climatic influence of ozone is due to its increase in the tropical troposphere. A recent international study, with participation of scientists from the Dept. of Atmospheric Chemistry and Climate of this Institute, shows that ozone concentration in the mid-troposphere (8-10 km) over the western Pacific is three times larger than in the tropics. From the analysis of satellite data, aircraft observations and climate modeling reported here it was concluded that fires in tropical Africa and Southeast Asia are the dominant source of high ozone over the western Pacific. High ozone and low water structures in the tropical western Pacific are commonly attributed to transport from the stratosphere or mid-latitudes. However, these observations suggest a larger role for biomass burning in the radiative forcing of climate in the remote tropical western Pacific than is commonly appreciated.

D. C. Anderson, J. M. Nicely, R. J. Salawitch, T. P. Canty, R. R. Dickerson, T. F. Hanisco, G. M. Wolfe, E. C. Apel, E. Atlas, T. Bannan, S. Bauguitte, N. J. Blake, J. F. Bresch, T. L. Campos, L. J. Carpenter, M. D. Cohen, M. Evans, R. P. Fernandez, B. H. Kahn, D. E. Kinnison, S. R. Hall, N. R. Harris, R. S. Hornbrook, J.-F. Lamarque, M. Le Breton, J. D. Lee, C. Percival, L. Pfister, R. R. Pierce, D. D. Riemer, A. Saiz-Lopez, B. J. Stunder, A. M. Thompson, K. Ullmann, A. Vaughan and A. J. Weinheimer. A pervasive role for biomass burning in tropical high ozone/low water structures. Nature Communications (2015).

DOI:10.1038/ncomms10267.

 

figura-nota-PNASDrought and salinity are the major threats to crop productivity at a worldwide scale. A fundamental portion of the plant response to these environmental stresses occurs at the cell membrane, where the molecular machinery to preserve cell turgor and the appropriate balance of intracellular ions is found. The C2-domain ABA-related (CAR) family of proteins contributes to these processes by delivering the regulatory proteins controlling this machinery from other cell compartments to the cell membrane. Our analysis provides an explanation on how CAR proteins specifically reach a particular membrane place to develop their function and trigger the plant defense mechanism against stress.

Maira Diaz, Maria Jose Sanchez-Barrena, Juana Maria Gonzalez-Rubio, Lesia Rodriguez, Daniel Fernandez, Regina Antoni, Cristina Yunta, Borja Belda-Palazon, Miguel Gonzalez-Guzman, Marta Peirats-Llobet, Margarita Menendez, Jasminka Boskovic, Jose A. Marquez, Pedro L. Rodriguez and Armando Albert. "Calcium-dependent oligomerization of CAR proteins at cell membrane modulates ABA signaling", PNAS (2015).
DOI: 10.1073/pnas.1512779113.

 

imagen-lytb

Streptococcus pneumoniae (the pneumococus), a superbug bacteria, is a leading cause of bacterial sepsis and the most frequent ethiologic-agent in the community adquired pneumoniae and non-epidemic bacterial meningitis. LytB, a member of the family of pneumococcal choline-binding protein, is responsible for the physical separation of daugther cells after division and participates in nasopharinx colonization and invasion, biofilm formation and evasion from the host immunity. Because of this, LytB is considered a putative vaccine/drug target. Here, IQFR and CIB investigators, in collaboration with scientists from the Universities of Newcastle (Newcastle upon Tyne, UK) and Notre Dame (Indiana, USA), have shown that LytB is a glucosaminidase and the basis for its high substrate specificity are unveiled. The catalytic mechanism and model of binding to the bacterial peptidoglycan together with determinants of its polar localization on pneumococcal cells is also advanced. Reported data provide a better understanding of the complex physiological role played by LytB in the bacterium and the host-pathogen interaction.

 

Rico-Lastres P, Díez-Martínez R, Iglesias-Bexiga M, Bustamante N, Aldridge C, Hesek D, Lee M, Mobashery S, Gray J, Vollmer W, García P, Menéndez M. 2015. “Substrate recognition and catalysis by LytB, a pneumococcal peptidoglycan hydrolase involved in virulence”. Sci Rep. 5:16198. doi: 10.1038/srep16198.