A mega-electron volt emission line in the spectrum of a gamma-ray burst.

A long gamma-ray burst (GRB) is observed when the collapse of a massive star produces an ultrarelativistic outflow pointed toward Earth. Gamma-ray spectra of long GRBs are smooth, typically modeled by joint power-law segments describing a continuum, with no detected spectral lines. We report a significant (>6σ) narrow emission feature at ~10 mega-electron volts (MeV) in the spectrum of the bright GRB 221009A.

Heavy Water Reduces the Electronic Conductance of Protein Wires via Deuteron Interactions with Aromatic Residues.

Proteins are versatile, self-assembling nanoelectronic components, but their hopping conductivity is expected to be influenced by solvent fluctuations. The role of the solvent was investigated by measuring the single molecule conductance of several proteins in both HO and DO. The conductance of a homologous series of protein wires decreases more rapidly with length in DO, indicating a 6-fold decrease in carrier diffusion constant relative to the same protein in HO.

Engineering gain-of-function mutants of a WW domain by dynamics and structural analysis.

Proteins gain optimal fitness such as foldability and function through evolutionary selection. However, classical studies have found that evolutionarily designed protein sequences alone cannot guarantee foldability, or at least not without considering local contacts associated with the initial folding steps. We previously showed that foldability and function can be restored by removing frustration in the folding energy landscape of a model WW domain protein, CC16, which was designed based on Statistical Coupling Analysis (SCA).

Gigaelectronvolt emission from a compact binary merger.

An energetic γ-ray burst (GRB), GRB 211211A, was observed on 11 December 2021. Despite its long duration, typically associated with bursts produced by the collapse of massive stars, the observation of an optical-infrared kilonova points to a compact binary merger origin. Here we report observations of a significant (more than five sigma) transient-like emission in the high-energy γ-rays of GRB 211211A (more than 0.

Design of novel cyanovirin-N variants by modulation of binding dynamics through distal mutations.

We develop integrated co-evolution and dynamic coupling (ICDC) approach to identify, mutate, and assess distal sites to modulate function. We validate the approach first by analyzing the existing mutational fitness data of TEM-1 β-lactamase and show that allosteric positions co-evolved and dynamically coupled with the active site significantly modulate function. We further apply ICDC approach to identify positions and their mutations that can modulate binding affinity in a lectin, cyanovirin-N (CV-N), that selectively binds to dimannose, and predict binding energies of its variants through Adaptive BP-Dock.