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In neurons and glia, glutamate transporters catalyse the reuptake of this neurotransmitter by coupling it with cation transport. Here the authors combine X-ray crystallography and molecular dynamics simulations of the archeal glutamate transporter Glt_Tkto get insight into the coupled transport mechanism.

Photosystem II (PSII) catalyzes the first light-dependent step in photosynthesis. An improved structural model of a cyanobacterial PSII provides complete assignment of all subunits in the complex and reveals possible channels used for the transport of protons, oxygen and water to the thylakoid lumen.

Archaeal glutamate transporter homologs catalyze the coupled uptake of aspartate and sodium ions. A new crystal structure of Glt_Tk from Thermococcus kodakarensis shows the empty transporter oriented in the outward-facing conformation after substrate delivery, revealing how it is reset in preparation for another translocation cycle.

Episodic ataxias (EAs) are rare neurological conditions that cause motor impairment. Here the authors investigated the molecular mechanism of such a pathological condition caused by a mutation of a conserved proline into arginine residue.

Glutamate transporters are membrane transporters that clear the neurotransmitter L-glutamate from the synaptic cleft via a so-called elevator mechanism. Here the authors present five cryo-EM structures of the transporter homologue Glt_Tk, which explain how substrate leakage is prevented.

A cryo-EM structure of the human SLC1 transporter ASCT2 in the inward-facing conformation reveals the retrovirus-docking site and helps to elucidate the transport cycle. The transport domain is more solvent exposed than in most of the homolog structures.

The bacterial zinc transporter ZntB is important for maintaining zinc homeostasis and is mechanistically not well understood. Here, the authors present the cryo-EM structure of ZntB at 4.2 Å resolution, perform transport assays and propose a model for its Zn²⁺ transport mechanism.

Prokaryotes use energy-coupling factor transporters to uptake required micronutrients and an unusual toppling mechanism has been proposed for their function. Here, the authors provide structural support for this mechanism, allowing direct visualization of the toppled state.

An X-ray crystal structure of substrate-bound Neisseria PnuC, a bacterial member of the SWEET family of transporters, provides key insights into the translocation mechanism and potential evolution of these membrane proteins.

When bacteria enter the stationary growth phase, protein translation is suppressed via the dimerization of 70S ribosomes into inactive complexes. Here the authors provide a structural basis for how the dual domain hibernation promotion factor promotes ribosome dimerization and hibernation in bacteria.

How the human Alanine Serine Cysteine Transporter 2 (ASCT2) binds its substrates, neutral amino acids, and releases them on the cytoplasmic side remains unclear. Here authors present an inward-open structure of the human ASCT2 which shows that a hairpin serves as a gate in the inward-facing state.

Energy coupling factor (ECF) transporters are responsible for the uptake of micronutrients and consist of an integral membrane unit, the S-component, which confers substrate specificity. Here, authors present multi-scale molecular dynamics simulations and in vitro experiments to study the molecular toppling mechanism of the S-component of a folate-specific ECF transporter.

Trinco et al. measure aspartate uptake rates in proteoliposomes containing purified prokaryotic Na⁺-coupled aspartate transporter GltTk. To overcome limitation of protein orientation, they use synthetic nanobody that blocks transporters from outside and reveal mechanistic features of Na⁺-aspartate symport that cannot be observed in detergent solution.