This issue's outside front cover was designed by Edward Tate and colleagues at Imperial College London, UK. The cover depicts in vivo enzymatic tagging and in vitro capture of recombinant proteins using an engineered bacterial co-expression system. 

 

The inside front cover was provided by Andrew McAnoy at the Defence Science and Technology Organisation, Fishermans Bend, Australia, and colleagues. In their paper, the team investigate the reactions of the hydroperoxide anion with a chemical warfare agent simulant, dimethyl methylphosphonate, in an ion trap mass spectrometer. They show that the reaction barrier leading to "deactivation" of the chemical warfare simulant is significantly lower for the hydroperoxide anion than for other nucleophiles, providing new insights for the decontamination of chemical and biological warfare agents.

 

In their Emerging Area, Michal Hocek and Miroslav Fojta at the Academy of Sciences of the Czech Republic, Prague, review the construction of functionalised nucleic acids via polymerase incorporation of modified nucleoside triphosphates and highlight selected applications of the modified nucleic acids.

 

Cell-penetrating peptides have found numerous applications in biology and medicine since the first synthetic cell-permeable sequence was identified two decades ago, and have captured the interest of an interdisciplinary community. In this issue's Perspective, Shana Kelley and colleagues at the University of Toronto, Canada, highlight achievements in this interesting area of peptide chemistry.