On the front cover: Kenzo Fujimoto and colleagues at the Japan Advanced Institute of Science and Technology have developed a simple and rapid method for identifying single nucleotide polymorphisms using sequence specific interstrand photocrosslinking.

Perspective: In the life sciences, it is an important challenge to understand the recognition and interaction of biologically active systems on an atomic scale. In this Perspective, Peter Luger at the Free University of Berlin, Germany, predicts that in the near future, fast electron density methods will routinely be used to provide the electronic properties of the interacting systems.

Perspective: NAD⁺ is well known for its role as a redox co-enzyme required for cellular processes. In this Perspective, Hening Lin at Cornell University, US, discusses one of NAD⁺'s other functions, as a co-substrate for ADP-ribosyltransferase enzymes. 

Essay: Intra- and intermolecular forces in biopolymers are critically dependent on their surroundings and, therefore, microenvironment polarity is a very important issue. Renatus Sinkeldam and Yitzhak Tor at the University of California, US, discuss attempts to probe the polarity of biological cavities.

Hot Article: A team of chemists lead by Robert Field at the University of East Anglia, Norwich, UK, and Ivone Carvalho at the University of São Paulo, Brazil, have developed a method to make molecules that will help to develop a cure for Chagas' Disease, a debilitating parasitic infection common in South and Central America.

Hot Article: Microcin J25 (MccJ25) is a natural peptide antibiotic produced by specific strains of the bacterium E. coli. Dominic Campopiano and David Clarke at the University of Edinburgh, UK, report for the first time the in vitro maturation of the microcin precursor peptide into active microcin J25.

Hot Article: Steven Ley and colleagues at the University of Cambridge, UK, describe an efficient new route to enantiopure 1,2-oxazines and pyridazines from achiral precursors using an organocatalyst.