Reviews & Analysis

Cell-surface carbohydrates are synthesized in a step-wise fashion, yielding products with unique capping structures. A recent study has shown that carbohydrates at the cell surface can be further remodeled by an endogenous glycosidase to alter the carbohydrate structure, thus generating a new function.

The berberine bridge enzyme catalyzes the crucial step in the biosynthesis of an important class of alkaloids through a reaction that cannot be carried out using conventional organic chemistry tools. Characterization of the enzyme demonstrates a concerted mechanism that couples two distinct chemical steps—oxidation and proton abstraction—affecting two separate groups of the substrate.

Isoginkgetin has been identified as a general inhibitor of pre-mRNA splicing using an in vivo screening assay. This and related inhibitors will not only be useful as tools to decipher the roles of the individual components of the spliceosome but may also serve as therapeutics.

X-ray scattering from clusters of gold atoms provides a sensitive way of measuring long-range distance information in macromolecules and now reveals a surprisingly soft, stretchy character to double-stranded DNA.

Bacterial infections have long been associated with coagulation, but the mechanism is not well understood. New insights into bacterial spatial localization are shedding light on how bacterial clusters can trigger coagulation in a process known as 'quorum acting'.

Small-molecule inhibitors of anti-apoptotic Bcl-2 proteins and BH3 mimetic peptides are promising anticancer agents. A recent study identifies a Nur77-based peptide that converts anti-apoptotic Bcl-2 proteins into pro-apoptotic molecules, providing another potential cancer therapeutic strategy.

Voltage-gated K⁺ channels assemble into complexes with Kvβs, a group of aldoketoreductases. The Kvβs regulate channel gating and localization, and voltage-dependent changes in the channel regulate AKR activity. Pan and colleagues now propose a new type of modulation of this complex. Cortisone disrupts the complex and relieves channel inactivation—which should reduce neuronal excitability.

Multitargeted protein kinase inhibitors have shown great promise in cancer therapy, but the selectivity profiles of these compounds have largely relied on serendipity or 'off-target' activities rather than rational drug design. Purposefully designed compounds with activity against multiple target kinases bring us a step closer to personalized medicine.

The emergence of a primordial RNA world would have required the formation of RNA polymers of sufficient length to possess catalytic activities, which are difficult to obtain by spontaneous polymerization. An analysis of an autocatalytic assembly pathway that can self-construct a functioning ribozyme from smaller oligonucleotide building blocks describes a potential route for RNA extension.

The execution phase of cell death is driven by specific proteolytic signaling through cleavage of proteins by caspases. Within the mix of hundreds of newly identified caspase substrates lie the crucial proteolytic events whose sum defines the unique morphology known as apoptosis.

Bacteria produce and excrete toxic compounds classically categorized as waste products or chemical weapons. New work indicates a role for phenazines and SoxR, a transcription factor known for its role in defense against oxidative stress, in coordinating bacterial community growth.

Metallothioneins sequester cadmium and surplus atoms of copper and zinc to prevent aberrant metal-catalyzed reactions. The identification of a 'cryptic' copper metallothionein in the bacterium that causes tuberculosis suggests that bacterial metallothioneins may be more widespread than previously suspected.