Assembly Mechanism of Recombinant Proteins

研究人员已经能够对具有新特性的蛋白质基材料进行基因工程改造。例如，丝绸弹性蛋白（silk-elastin-like protein, selp）是通过将天然丝绸的多肽序列与具有优异机械强度的人体弹性蛋白融合成单个蛋白质而合成的。然而，重组蛋白，如selp，仍然不能通过绿色通道组装成坚固的微/纳米级生物医学结构。流程。相比之下，蜘蛛可以在常温、低压和水作为溶剂的条件下纺出强度更高的丝纤维。本提案的目的是了解重组蛋白在绿色环境下的组装机制。条件和表征组装蛋白纤维的结构和机械性能。特别是，微流体装置将用于研究蛋白质溶液变量（如pH值，盐浓度），制造变量（如流速）和蛋白质序列对selp受控组装和纤维形成的影响。组装的SELP纤维的力学性能将被表征和数学建模。此外，利用傅里叶变换红外拉曼光谱分析了SELP纤维的二级结构。拟议的研究将为“绿色”的发展提供必要的第一步。生产用于各种生物医学应用的高性能蛋白质纤维的制造工艺。研究结果将被整合到本科和研究生的联合课程“微生物力学”中。从事这项研究的本科生和研究生，包括未被充分代表的少数民族和女性，将接受生物力学、纳米技术和生物材料等新兴领域的培训。

Researchers have been able to genetically engineer protein-based materials with novel properties. For instance, silk-elastin-like proteins (SELPs) have been synthesized by fusing polypeptide sequences, derived from native silk of superior mechanical strength, and human elastin, which is remarkably resilient, into single proteins. However, recombinant proteins, like SELPs, still cannot be assembled into robust micro/nanoscale biomedical structures via ?green? processes. In contrast, spiders can spin silk fibers of superior strength at ambient temperatures, low pressures, and with water as the solvent. The objective of this proposal is to understand the assembly mechanism of recombinant proteins under ?green? conditions and to characterize the structure and mechanical properties of assembled protein fibers. In particular, a micro-fluidic device will be used to investigate the influence of protein solution variables (e.g., pH, salt concentrations), fabrication variables (e.g., flow rates), and protein sequences on the controlled assembly and fiber formation of SELPs. The mechanical properties of assembled SELP fibers will be characterized and mathematically modeled. In addition, the secondary structures of SELP fibers will be analyzed using Fourier transform infrared Raman spectroscopy. The proposed research will provide the necessary first step toward the development of ?green? fabrication processes for producing high-performance protein fibers for a variety of biomedical applications. Results from the research will be integrated into the combined undergraduate and graduate course entitled Micro-Biomechanics. Undergraduate and graduate students performing the research, including underrepresented minorities and women, will receive training in the emerging areas of biomechanics, nanotechnology, and biomaterials.