Ishchuk Olena P, Martínez José L, Petranovic Dina
Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, Gothenburg, Sweden.
Department of Biotechnology and Biomedicine, Section for Synthetic Biology, Technical University of Denmark, Kongens Lyngby, Denmark.
Methods Mol Biol. 2019;1923:243-264. doi: 10.1007/978-1-4939-9024-5_11.
Human hemoglobin is an essential protein, whose main function as an oxygen carrier is indispensable for life. Hemoglobin is a cofactor-containing protein with heme as prosthetic group. Same as in humans, heme is synthesized in many organisms in a complex pathway involving two cellular compartments (mitochondria and cytosol), which is tightly regulated. Red blood cells (erythrocytes) are specialized and adapted for production and transport of the hemoglobin molecules. In addition to oxygen binding, hemoglobin can participate in a variety of chemical reactions by its iron and heme and may become toxic when released from erythrocytes. Hemoglobin is a major target for the development of blood substitutes/oxygen carriers, and therefore its microbial production is attractive, as it may provide a cheap and reliable source of human hemoglobin. Significant efforts have been dedicated to this task for the last three decades. Moreover since the first generation of cell-free blood substitutes based on unmodified hemoglobin failed human trials, mutant forms became of great interest.In this chapter we summarize the existing knowledge about human hemoglobin, challenges of its microbial production, and its improvement, with a particular focus upon yeast as production host.
人类血红蛋白是一种必需蛋白质，其作为氧气载体的主要功能对生命而言不可或缺。血红蛋白是一种含辅因子的蛋白质，以血红素作为辅基。与人类一样，血红素在许多生物体中通过一条涉及两个细胞区室（线粒体和细胞质）的复杂途径合成，该途径受到严格调控。红细胞专门用于生产和运输血红蛋白分子。除了结合氧气外，血红蛋白还可通过其铁和血红素参与多种化学反应，从红细胞中释放出来时可能会产生毒性。血红蛋白是血液替代品/氧气载体开发的主要目标，因此其微生物生产具有吸引力，因为它可能提供一种廉价且可靠的人类血红蛋白来源。在过去三十年里，人们为这项任务付出了巨大努力。此外，由于第一代基于未修饰血红蛋白的无细胞血液替代品人体试验失败，突变形式引起了极大关注。在本章中，我们总结了关于人类血红蛋白的现有知识、其微生物生产面临的挑战以及改进方法，特别关注作为生产宿主的酵母。
