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Horizontal gene transfer (HGT) is a major driver of evolution and a key source of innovation in the microbial world. Mobile genetic elements (MGEs), such as plasmids and phages, often act as agents of HGT or as vehicles for cargo genes, some of which define the adaptive potential of the host organism in specific environments. These genes are involved in immunity, anti-immunity, virulence, and anti
The use of X-ray structures to determine and interpret the ferryl iron-oxygen bond order in molecular oxygen-activating heme enzymes has, in the past, been controversial. This has mainly stemmed from the susceptibility of ferryl species to X-ray-induced electronic state changes. In this work we establishe using time-resolved serial femtosecond X-ray crystallography (tr-SFX) on a dye-decolourising
Epoxide hydrolases are essential enzymes that convert epoxides into 1,2-diols, contributing to detoxification, metabolism, and signaling in a wide range of organisms. In this study, we employed hybrid quantum mechanics/molecular mechanics (QM/MM) calculations to investigate the catalytic mechanism of potato epoxide hydrolase 1 (StEH1), specifically focusing on the hydrolysis of trans-stilbene oxid
Quantum refinement (QR) is an approach in which the empirical restraints used in standard structural refinement to ensure that the details of the structure, e.g. bond lengths and angles, make chemical sense are replaced by more accurate quantum mechanical calculations for a small but interesting part of the structure. QR has previously been used for X-ray and neutron crystallography, cryogenic
We present an updated characterization of the planetary system orbiting the nearby M2 dwarf GJ 3090 (TOI-177; d=22 pc), based on new high-precision radial velocity (RV) observations from NIRPS and HARPS. With an orbital period of 2.85 d, the transiting sub-Neptune GJ 3090 b has a mass we refine to 4.52 ± 0.47 M>, which, combined with our derived radius of 2.18 ± 0.06 R2, yields a density of 2.40-0
The intense stellar irradiation of ultra-hot Jupiters results in some of the most extreme atmospheric environments in the planetary regime. On their daysides, temperatures can be sufficiently high for key atmospheric constituents to thermally dissociate into simpler molecular species and atoms. This dissociation drastically changes the atmospheric opacities and, in turn, critically alters the temp
Context. The Near InfraRed Planet Searcher (NIRPS) joined HARPS on the 3.6-m ESO telescope at La Silla Observatory in April 2023, dedicating part of its Guaranteed Time Observations (GTO) program to the radial velocity follow-up of TESS planet candidates to confirm and characterize transiting planets around M dwarfs. Aims. We present the “Sub-Neptunes” subprogram of the NIRPS-GTO, aimed at investi
We explore interactions between equally charged surfaces in the presence of simple salt and either neutral or monovalently charged polyampholytes. We consider the possibility of using these charged polymers as crude models of ion clusters. The latter have been hypothesized to form in concentrated aqueous salt solutions and are possibly related to anomalous underscreening. This phenomenon usually m
The Haro 11 galaxy merger is the closest known Lyman continuum (LyC) leaker and a strong Lyman-α (Lyα) emitter, making it an important analogue of the high-z galaxies that reionised the early Universe. To investigate how Haro 11’s properties arise, we perform a radiation hydrodynamics simulation of the merger, and create mock observations of LyC, Lyα, and Hα, from which we compute their luminositi
Ion clustering has been proposed as a mechanism leading to the peculiar "anomalous underscreening" phenomenon seen for electrostatic interactions between charged surfaces immersed in concentrated electrolytes. These interactions have been measured using the Surface Force Apparatus, according to which there are strong repulsive interactions between like-charged surfaces, with a range that increases
The chemical abundances of stars in galaxies are a fossil record of the star formation and stellar evolution processes that regulate galaxy formation, including the stellar initial mass function, the fraction and timing of type Ia supernovae (SNeIa), and nucleosynthesis inside massive stars. In this paper, we systematically explore uncertainties associated with modeling chemical enrichment in dwar
Current star formation models are based on the structure of the interstellar medium (ISM), yet the details on how local physics propagates to galactic-scale properties are still debated. To investigate this, we use VINTERGATAN, a high-resolution cosmological zoom-in simulation of a Milky Way-like galaxy. We study how the velocity dispersion and density structure of the cold neutral ISM on 50–100 p
High-resolution transmission spectroscopy has become a powerful tool for detecting atomic and ionic species in the atmospheres of ultra-hot Jupiters. In this study, we demonstrate for the first time that the Australian-built Veloce spectrograph on the 3.9-m Anglo-Australian Telescope can resolve atmospheric signatures from transiting exoplanets. We observed a single transit of the ultra-hot Jupite
Context. Ultra-hot Jupiters (UHJs) in close orbits around early-type stars provide natural laboratories for studying atmospheric escape and star-planet interactions under extreme irradiation and wind conditions. The near-ultraviolet (NUV) regime is particularly sensitive to extended upper atmospheric and magnetospheric structures. Aims. We investigate whether star-planet interactions in the WASP-1
The Galactic center and inner disk of the Milky Way contain complex stellar populations obscured by heavy dust extinction. To study their chemical composition, high-resolution near-infrared (near-IR) spectroscopy is necessary. Expanding the set of elements measurable in the near-IR, especially neutron-capture elements, improves our ability to trace nucleosynthesis and Galactic chemical evolution.
Recent hydrodynamical simulations of isolated barred disc galaxies have suggested a structural change in the distribution of the interstellar medium (ISM) around a stellar mass M∗ of 1010 M⊙. In the higher-mass regime (M∗ ≤ 1010 M⊙), we observe the formation of a central gas and stellar disc with a typical size of a few hundred parsecs connected through lanes to the ends of the stellar bar. In the
Structural optimization aims to find the geometry of the best performing design in a predefined setting, using mathematical techniques. The motivation for this study can be categorized into three main benefits: efficient material usage, enhancing existing designs and enabling new technologies. All of these benefits are crucial for solving contemporary technological and environmental challenges. An
β-Alanine synthase (βAS), which is a dizinc metalloenzyme, catalyzes the irreversible hydrolysis of N-carbamyl-β-alanine (NCβA) to β-alanine. This enzyme has potential applications for β-amino acid production. Understanding the reaction mechanism and selectivity of βAS at atomic details can help design and engineer the enzyme for cascade biocatalysis. Here, the protonation states of two conserved
Star clusters stand at the crossroads between galaxies and single stars. Resolving the formation of star clusters in cosmological simulations represents an ambitious and challenging goal, since modelling their internal properties requires very high resolution. This paper is the third of a series within the SImulating the Environment where Globular clusters Emerged (SIEGE) project, where we conduct
Haro 11 is a metal-poor, starburst galaxy believed to be the result of an ongoing merger, which is shaping the properties of the galaxy. In this study, we carry out a large suite of numerical simulations of a merger between two disc galaxies, to study possible origins of Haro 11 and understand under which conditions various features of the galaxy are formed. By varying galaxy parameters describing
