Engineering Living/Synthetic Hybrid Assemblies (LSHAs) as Functional Units for Synthetic Biology

该奖学金的总体愿景涉及以下问题：如何将生物结构（即细胞）与人工构建的元素（即以分子机械功能化的囊泡为基础的合成细胞）结合起来，以构建活/合成混合组件（LSHAs）？回答这个问题需要克服重大的技术障碍，这也是本研究的重点。合成生物学关注的是与自然界不同的生物系统的构建。合成细胞既可以自上而下地通过获取细胞并操纵它们的基因组来制造，也可以自下而上地通过使用用户定义功能的简单化学构建块从零开始构建人工细胞来制造。技术瓶颈意味着这两种方法彼此孤立存在，从而阻碍了这门学科的力量和潜力。开发的lsha将有助于弥合这一鸿沟。这对合成生物学具有战略意义：它有望开辟一个新的研究领域，并提供应用——从生物合成和生物传感，到生化计算和治疗递送——这将进一步巩固该领域作为关键新兴技术的地位。构建杂交细胞的策略将集中在使用基于液滴的微流体将细胞封装在功能化的合成脂质囊泡中。通过这种方式，混合细胞将能够进入生物系统中固有的复杂生化途径，但仍然包含自下而上设计的定制功能的人工构建元素。因此，LSHAs可以被认为是一类新的“人工真核生物”：它们将由一个囊泡宿主和一个享有互利关系的细胞共生体组成。将设计一套工程规则，以生物化学方式连接合成宿主和被封装的细胞，并开发两者之间的通信路线。接下来，将通过一系列概念验证研究来展示它们作为一套尖端应用程序的用途。这些包括(i)通过囊泡内的化学成分对分泌的细胞产物进行下游处理，（ii）使用LSHA作为实现“膜移植”的手段——用确定大小、组成和不对称的人工膜代替细胞质膜，以及（iii）连接多个LSHA单元，形成能够处理和传播化学信号的大规模网络。因此，该奖学金将作为一个可行性路线图，概述哪些策略和应用可行，哪些无效，以帮助该领域的未来发展。这项研究将在帝国理工学院化学系进行。它将属于化学生物学研究所的范围，并利用其一些最先进的微流体，光学捕获和显微镜设备，专门用于研究这些系统。它还将与Booth教授（伦敦国王学院）合作进行，Booth教授将为通过机械敏感孔整合智能、响应性行为提供关键支持，并与Yitzhak Mastai教授（以色列巴伊兰）合作，将手性分子元素添加到杂交细胞中。

The overarching vision of the fellowship concerns the following question: how can biological structures (i.e. cells) be coupled with artificially-constructed elements (i.e. vesicle-based synthetic cells functionalised with molecular machinery) for the construction of living/synthetic hybrid assemblies (LSHAs)? Answering this question requires that significant technological hurdles be overcome, and this is the focus of this fellowship.Synthetic biology concerns itself with the construction of biological systems unlike those seen in nature. Synthetic cells can either be engineered from the top-down, by taking cells and manipulating their genome, or from the bottom-up, by building artificial cells from scratch using simple chemical building-blocks for user-defined functions. A technological bottleneck has meant that these two approaches have existed in isolation from one another, thus hampering the power and potential of the discipline. The LSHAs developed will serve to bridge this divide. This is of strategic importance to synthetic biology: it promises to open up a new research field and deliver applications-from biosynthesis and biosensing, to bio-chemical computing and therapeutic delivery-that would further cement the area as a key emerging technology.Strategies to construct hybrid cells will centre on using developing droplet-based microfluidics to encapsulate cells within functionalised synthetic lipid vesicles. In this way, the hybrid cells will have access to the complex biochemical pathways inherent in biological systems, yet still contain artificially-constructed elements designed from the bottom up for bespoke functionality. LSHAs can thus be considered as a novel class of 'artificial eukaryote': they will consist of a vesicle host and a cellular symbiont enjoying a mutually beneficial relationship. A set of engineering rules to biochemically interface the synthetic host with the encapsulated cells will be devised and communication routes between the two will be developed.Next, their use as a suite of cutting-edge applications via a series of proof-of-concept studies will be demonstrated. These include (i) downstream processing of secreted cellular products by chemical components contained within the vesicle, (ii) using LSHAs as a means to achieve 'membrane transplants'-the replacement of a cellular plasma membrane with an artificial membrane of defined size, composition and asymmetry, and (iii) linking up multiple LSHA units to form a large-scale network capable of processing and propagating chemical signals. This fellowship will therefore act a feasibility roadmap outlining which strategies and applications do and do not work, to aid future advances in the field.This research will be undertaken in the Department of Chemistry at Imperial College. It will fall within the bracket of the Institute of Chemical Biology, and make use of some of its state of the art microfluidic, optical trapping, and microscopy facilities specially tailored to study systems such as these. It also be conducted in partnership with Prof Booth (Kings College London), who will provide key support for the incorporation of smart, responsive behaviours via mechanosensitive pores, and with Prof Yitzhak Mastai (Bar Ilan, Israel) for the addition of chiral molecular elements into the hybrid cell.