Understanding taste is key for optimizing the palatability of seaweeds and other non-animal-based foods rich in protein. The lingual papillae in the mouth hold taste buds with taste receptors for the five gustatory taste qualities. Each taste bud contains three distinct cell types, of which Type II cells carry various G protein-coupled receptors that can detect sweet, bitter, or umami tastants, while type III cells detect sour, and likely salty stimuli. Upon ligand binding, receptor-linked intracellular heterotrimeric G proteins initiate a cascade of downstream events which activate the afferent nerve fibers for taste perception in the brain. The taste of amino acids depends on the hydrophobicity, size, charge, isoelectric point, chirality of the alpha carbon, and the functional groups on their side chains. The principal umami ingredient monosodium l-glutamate, broadly known as MSG, loses umami taste upon acetylation, esterification, or methylation, but is able to form flat configurations that bind well to the umami taste receptor. Ribonucleotides such as guanosine monophosphate and inosine monophosphate strongly enhance umami taste when l-glutamate is present. Ribonucleotides bind to the outer section of the venus flytrap domain of the receptor dimer and stabilize the closed conformation. Concentrations of glutamate, aspartate, arginate, and other compounds in food products may enhance saltiness and overall flavor. Umami ingredients may help to reduce the consumption of salts and fats in the general population and increase food consumption in the elderly.
MULTIFILE
pH-sensitive gels: By using a cyclohexane-based scaffold to which various amino acid based substituents can be connected, low-molecular-weight compounds were obtained that can gelate water at very low concentrations. Their modular design (see picture: AA = amino acid(s), X = hydrophilic substituent, dark purple = hydrophobic region, light purple = hydrophilic region), allows tuning of the thermally and pH-induced reversible gel-to-sol transition of their gels.
The objective of this study was to generate groups of agri-food producers with high affinity in relation to their sustainable waste management practices. The aim of conforming these groups is the development of synergies, knowledge management, and policy- and decision-making by diverse stakeholders. A survey was conducted among the most experienced farmers in the region of Nuevo Urecho, Michoacán, Mexico, and a total of eight variables relating to sustainable waste management practices, agricultural food loss, and the waste generated at each stage of the production process were examined. The retrieved data were treated using the maximum inverse correspondence algorithm and the Galois Lattice was applied to generate clusters of highly affine producers. The results indicate 163 possible elements that generate the power set, and 31 maximum inverse correspondences were obtained. At this point, it is possible to determine the maximum number of relationships, called affinities. In general, all 15 considered farmers shared the measure of revaluation of food waste and 90% of the farmers shared affinity in measures related to ecological care and the proper management of waste. A practical implication of this study is the conformation of highly affine clusters for both policy and strategic decision-making.
LINK
Structural and functional knowledge of proteins, which are essential in biological processes, is fundamental for our understanding of the Chemistry of Life. Structural biology - the field that studies the structure and function of proteins – has seen several revolutions over the last few years. Single particle analysis (SPA), where individual macromolecular assemblies are imaged under cryogenic conditions within highly automated electron microscopes, has been used to elucidate the structures of many novel and important proteins and complexes. Deep-learning–based computational techniques provided systematic predictions of an million three-dimensional protein structures. Cryo-electron tomography (ET) combined with sub-tomogram averaging (STA) enabled the investigation of conformational states of large macromolecular complexes. We expect in situ structural biology, where macromolecular assemblies are studied within the interior of focused-ion-beam milled frozen cells, to become the next revolution in our field. Such revolution would require well prepared vitreous samples (cells, tissue slices, organoids): the sample should be cooled fast enough to prevent the formation of crystalline ice. Previously, we developed the technology to prepare SPA samples using jets of cryogenic fluid directed onto the sample. This device, the VitroJet, has been further developed into a commercial product by CryoSol-World and has been sold worldwide. Here, we wish to advance the jetting technology such that it can vitrify cells. Crucial aspects are the speed of the jets and the timing and reproducibility of the fronts of the cryogens arriving onto the sample. We will design, build, characterise and refine a next generation of the ethane cup, a core component within the VitroJet. If successful, we should be able to increase its vitrification potential as well as its reproducibility by more than one order of magnitude. This technology will enable in situ structural biology studies necessary to understand the Chemistry of Life.
