ABCC transporters mediate the vacuolar accumulation of crocins in saffron stigmas
Demurtas OC, Francisco RB, Diretto G, Ferrante P, Frusciante S, Pietrella M, Feeney M, Frigerio L, Martinoia E, Giuliano G
Compartmentation is a key strategy enacted by higher plants for the storage of specialized metabolites. The saffron spice owes its red color to crocins, a complex mixture of apocarotenoid glycosides that accumulate in intracellular vacuoles and reach up to 10% of the spice dry weight. We developed a general approach, based on coexpression analysis, heterologous expression in yeast, and in vitro "transportomic" assays using yeast microsomes and total plant metabolite extracts, for the identification of putative vacuolar metabolite transporters, and used it to identify saffron transporters mediating vacuolar crocin accumulation.
Phill Stansfeld publications
Insights into Membrane Protein-Lipid Interactions from Free Energy Calculations
Robin A Corey, Owen N Vickery, Mark S P Sansom & Phillip J Stansfeld
Integral membrane proteins are regulated by specific interactions with lipids from the surrounding bilayer. The structures of protein–lipid complexes can be determined through a combination of experimental and computational approaches, but the energetic basis of these interactions is difficult to resolve. Molecular dynamics simulations provide the primary computational technique to estimate the free energies of these interactions. We demonstrate that the energetics of protein–lipid interactions may be reliably and reproducibly calculated using three simulation-based approaches: potential of mean force calculations, alchemical free energy perturbation, and well-tempered metadynamics. We demonstrate good agreement between the different techniques, providing a robust framework for their automated implementation within a pipeline for annotation of newly determined membrane protein structures.
Clot-derived contaminants in transplanted bone marrow mononuclear cells impair the therapeutic effect in stroke
Okinaka Y, Kikuchi-Taura A, Takeuchi Y, Ogawa Y, Boltze J, Gul S, Claussen C, Taguchi A
The beneficial effects of bone marrow mononuclear cell (BM-MNC) transplantation in preclinical experimental stroke have been reliably demonstrated. However, only overall modest effects in clinical trials were observed. We have investigated and reported a cause of the discrepancy between the preclinical and clinical studies. We found that the transplanted contaminants were trapped at the peristroke area, which were associated with microglial/macrophage activation. Clot-derived contaminants in transplanted BM-MNC nullify therapeutic effects in experimental stroke. This may explain neutral results in clinical trials, especially in those using automated stem cell separators that lack the ability to remove clot-derived contaminants.
Assembly and characterisation of a unique onion diversity set identifies resistance to Fusarium basal rot and improved seedling vigour
Conserving biodiversity is critical for safeguarding future crop production. Onion (Allium cepa L.) is a globally important crop with a very large (16 Gb per 1C) genome which has not been sequenced. Onion yield losses regularly occur worldwide due to Fusarium basal rot. Accessions with strong basal rot resistance and increased seedling vigour were identified along with associated markers, confirming the utility of the diversity set for discovering beneficial traits. The onion diversity set and associated trait data therefore provide a valuable resource for future germplasm selection and onion breeding.
Microencapsulation of enteric bacteriophages in a pH-responsive solid oral dosage formulation using a scalable membrane emulsification process
Gurinder K. Vinner, Kerry Richards, Miika Leppanen , Antonia P. Sagona , and Danish J. Malik
A scalable low-shear membrane emulsification process was used to produce microencapsulated Escherichia coli-phages in a solid oral dosage form. The encapsulated phages were stable during refrigerated storage over a four-week period. The process of membrane emulsification is highly scalable and is a promising route to produce industrial quantities of pH-responsive oral solid dosage forms suitable for delivering high titres of viable phages to the gastrointestinal tract.
Multi-site rate control analysis identifies ribosomal scanning as the sole high-capacity/low-flux-control step in mRNA translation
Helena Firczuk, James Teahan, Pedro Mendes and John EG McCarthy
Control of complex intracellular pathways such as protein synthesis is critical to organism survival, but is poorly understood. Translation of a reading frame on eukaryotic mRNA is preceded by a scanning process in which a subset of translation factors helps guide ribosomes to the start codon. Here, we perform comparative analysis of the control status of this scanning step that sits between recruitment of the small ribosomal subunit to the mRNA and of the control exerted by downstream phases of polypeptide initiation, elongation and termination. We conclude that the components of the translation machinery that promote scanning collectively function as a low‐flux‐control system and the step immediately prior to scanning is a high‐flux‐control step.