The structures of Orn-free Gramicidin S with cis/trans-isomers of Hyp were solved, and the puckering of Hyp was unexpectedly down in both isomers.

The crystal structure of the nonstoichiometric complex of gramicidin D with NaI has been studied using synchrotron radiation at 100 K.

Gramicidin S, a membrane-active antibiotic, was crystallized from solvent containing water, methanol, trifluoroacetic acid and hydrochloric acid. The structure was refined at 0.95 Å resolution and contains 1.5 molecules of gramicidin S, two trifluoracetic acid molecules and ten water molecules in the crystallographic asymmetric unit. In the crystals, the gramicidin S molecules line up into helical channels that differ from those observed previously.

[Leu]Gramicidin S could be a novel scaffold for studying β-turn and sheet structures.

Structure of double-stranded right-handed double-helical gramicidin channels (dimers) in the crystal of gramicidin D with KI complex has been determined. High-resolution data enabled quantitative determination of gramicidin components and distributions of the I anions outside and K cations inside the channel, which was confirmed by their anomalous scattering.

Recent work applying neutron and X-ray scattering to elucidate the molecular mechanisms of volatile anesthetics is reviewed.

A 1.14 Å resolution study on the gramicidin D complex with RbCl confirms its right-handed antiparallel double-stranded dimeric structure. Rb cations distributed over seven binding sites in each gramicidin channel unit are `coordinated' by delocalized π-electrons of three to five carbonyl groups from the channel wall and by two water molecules.

A nonribosomal peptide synthetase di-domain construct was produced using known crystal packing as a guide, and the resulting crystal has an unanticipated packing.

The X-ray structure of the cyclo-decapeptide, gramicidin S, is reported. it forms a twisted β-sheet, with two Phe residues in the D conformation to allow the necessary tight turns. Gramicidin S acts on cellular membranes, interacting with the lipid components, and the crystal symmetry generates a left-handed double spiral of molecules forming channels which could span the membrane.

A comprehensive and up-to-date review of the lipid cubic phase or in meso method for crystallizing membrane and soluble proteins and complexes is reported. Recent applications of the method for in situ serial crystallography at X-ray free-electron lasers and synchrotrons are described.