Speaker: Felix Sigmund, Helmholtz Zentrum München - Doctoral student in the research group "Molecular Neuroimaging" led by Prof. Gil Westmeyer
Time: 12 November 2019, 1 pm
Place: Munich School of BioEngineering (Lecture Hall E.126, Boltzmannstr. 11, 85748 Garching)
Abstract: Many discoveries in biology have emerged from the ability to observe previously invisible biological processes at the molecular level. The green fluorescent protein (GFP), a contrast agent that is genetically-encoded and generated inside living cells, can deliver unprecedented insights into the inner workings of cells and has thus revolutionized biology research. However, fluorescence techniques are limited by the poor penetration of visible light into biological tissues. Furthermore, high-resolution electron microscopy techniques (EM) might be needed to decipher a biology system fully. Genetically-encoded imaging agents for non-invasive techniques such as MRI and optoacoustic imaging and equivalent tools for high-resolution EM offering the same utility as GFP are still sparse and hence highly demanded.
In this talk, I will introduce 'Encapsulins,' a class of prokaryotic proteins that auto-assemble and form icosahedral porous nano-compartments (18 – 43 nm) that contain enzymatically active cargo proteins that in some Encapsulin systems biomineralize iron oxides. We have demonstrated that Encapsulin systems from different bacterial origins can be genetically expressed in mammalian cells where they assemble and effectively biomineralize intraluminal iron oxide cores. Furthermore, we have shown that foreign cargo proteins can be genetically targeted into the Encapsulin lumen, thus allowing to engineer tailor-made reaction vessels with different functions. Based on these capabilities, we have bioengineered Encapsulins that can serve as genetically-encoded molecular markers for MRI, optoacoustic imaging, and electron microscopy, thus spanning multiple scales of molecular imaging. In the end, I will briefly touch upon how Encapsulins can serve as magnetic actuators and outline future research directions for bioengineering of Encapsulins.