Investigation of the interactions of proteins with fibrils in composite gel: a multiscale approach

这个涉及实验表征和理论方面的多学科项目旨在研究“惰性”多糖原纤维和蛋白质聚集体的凝胶状复合物的组分之间的相互作用，该复合物具有多个长度尺度（从宏观-胶体-纳米级）。我们的第一个目标是使用湿化学技术绘制宏观化学相互作用，然后使用先进的共聚焦显微镜和散射技术探测动态行为。蛋白质-原纤维复合物中的力（表面相互作用、结合-共价和非共价相互作用、机械力、粘附）的定量将在胶体和纳米级下表征，后者使用纳米机械技术。我们计划确定蛋白质和纤维中的关键基序以及控制组分相互作用和这种复合材料的整体结构和强度的因素（温度，pH值，链长）。我们的目标是使用数学模型和计算机模拟来开发介观模型，以了解：短程和静电相互作用的效果和强度，表面电荷密度，蛋白质纤维复合物中的表面电荷分布，并将实验结果与理论结果进行比较，以确定关键的控制相互作用和材料内的分布。蛋白质化学，胶体长度尺度上的实验性相互作用探测，流变学，成像（高级共焦显微镜与拉曼、低温扫描电子显微镜与能量色散X射线光谱（EDX））、散射-布伦特·默里教授/安维沙·萨卡尔教授（食品科学）原子力显微镜（AFM）技术在成像和力谱模式中的发展和应用，纳米力学（粘附力、拉力）和纳米级的生物聚合物网络表征。- Simon Connell博士（物理学）在胶体长度尺度上模拟相互作用，自洽场理论计算，布朗动力学，蒙特卡罗模拟-Rammile Ettelaie博士（食品科学）直接利用布拉格材料研究中心的设施（例如，Wellcome信托基金资助的具有力测量功能的高速共聚焦）（利兹电子显微镜和光谱学中心）（例如SEM和EDX）本研究将确定产生模型Quorn素食产品质地的关键相互作用。Quorn的未来增长将取决于用植物蛋白复制或增强这些纹理。希望这项工作的产出将加速植物蛋白的重新配方，使公司能够减少白色的使用，并进一步提高公司未来的可持续性/LCA概况。

This multidisciplinary project involving both experimental characterization and theoretical aspects aims to characterise the interactions between the components of a gel-like composite of 'inert' polysaccharide fibrils and protein aggregates at multiple length scales (from macro-colloidal-nanoscale). We first aim to map the macroscale chemistry of interactions using wet chemistry techniques and then probe the dynamic behaviour using advanced confocal microscopy and scattering techniques. Quantification of forces in the protein-fibril complex (surface interactions, bindings - both covalent and non-covalent interactions, mechanical forces, adhesion) will be characterized at colloidal and nanoscale, latter using nanomechanical techniques. We plan to identify key motifs in the protein and the fibrils and factors (temperature, pH, chain length) that control the component interactions and overall structure and strength of this composite material. We aim to develop mesoscopic models using mathematical models and computer simulations to understand: the effect and strength of short-range and electrostatic interactions, surface charge density, surface charge distribution in protein-fibre complexes and compare experimental results with theoretical results to pin-point the key controlling interactions and the distribution within the material. Protein chemistry, probing interactions experimentally at colloidal length scale, rheology, imaging (advanced confocal microscopy with Raman, cryo-scanning electron microscopy with Energy-dispersive X-ray spectroscopy (EDX)), scattering- Prof. Brent Murray/ Prof. Anwesha Sarkar (Food Sci) Development and application of atomic force microscopy (AFM) techniques in imaging and force spectroscopy mode, nanomechanics (adhesive forces, pulling forces), and biopolymer network characterisation at the nanoscale. - Dr Simon Connell (Physics) Modelling interactions at colloidal length scale, Self-consistent field theory calculations, Brownian dynamics, Monte Carlo simulations - Dr Rammile Ettelaie (Food Sci) Direct utilization of facilities at Bragg Centre of Materials Research (e.g. Wellcome trust-funded high speed confocal with force measurements) Direct utilization of facilities at LEMAS (Leeds Electron Microscopy and Spectroscopy Centre) (e.g. SEM with EDX) This study will identify what are the key interactions that generate the texture of a model Quorn vegetarian product. The future growth of Quorn will depend on replicating or enhancing these textures with plant proteins. It is hoped the output of this work will accelerate plant protein reformulation allowing the company to reduce egg white use and further improving the company sustainability/LCA profile into the future.