Potassium

Mobile group II introns function as ribozymes to splice and reinsert themselves into DNA, thereby colonizing new genomic regions. Here the authors use single-molecule FRET and molecular dynamics simulations to reveal a structural link between metal ion induced kinetic heterogeneity and the sugar puckers at the exon-intron binding interface.

Metal ions play essential roles in myriads of biological processes, from catalytic co-factors to supporting protein and nucleic acid structures. Here the authors use long-wavelength X-ray diffraction to locate hundreds of potassium ions taking part in the formation of rRNA tertiary structure, mediating rRNA–protein interactions and supporting ribosomal protein structures and function.

The crystal structure of the bacterial potassium import complex KdpFABC shows how ATP hydrolysis is coupled to potassium transport to maintain cellular homeostasis under low potassium conditions.

Salinization of cultivated land and the need to increase agricultural productivity make the development of salt-resistant crops imperative. Field trials show that a durum wheat containing a sodium transporter derived from an ancestral wheat relative produces substantially more grain than a commercial durum wheat lacking this transporter on saline soil.