Anhydrobiosis and protecting sensitive biomolecules

Given the fact that climate change is already with us, dessication tolerance of food crops is a much sought after property. Dessication tolerance is common throughout nature and can also be found for selected animals (see example of tardigrade or water bear) and microorganisms. Specific groups of molecules are known to protect sensitive biological structures (large protein complexes, biological membranes) against damage due to dehydration. For example, sugars such as trehalose and sucrose are accumulated during dehydration, but also a special class of disordered hydrophilic polypeptides called LEA’s (Late Embryogenesis Abundant). LEA’s were first identified in plants, but later also found in many other organisms. LEA polypeptides are believed to be very good for protecting sensitive biomolecules against possible damage due to drying. For example, these molecules are particularly interesting in the preservation of vaccines or other medicines consisting of very large biomacromolecules in the absence of a cold chain (as in developing countries), and in biosensors where sensitive antibodies are immobilized on a surface and stored as a dry product before their re-hydration and use. The PhD project of Nicolo is focused on the latter: we want to use a layer of engineered LEAs as a protective “cushion” for antibodies on sensor chips, to better maintain their activity when they are dried. The project is in collaboration with biosensor companies, and we appear to be the first who are attempting to engineer LEA’s for technological applications.

Techniques: in-silico DNA design, molecular cloning, protein expression in E. coli, protein purification & characterisation (SDS-PAGE, mass spectrometry), studying protein adsorption using Quartz Crystal Microbalance (QCM), studying biofouling on adsorbed protein layers using QCM, studying protective effect of LEAs on antibodies using spectroscopy and calorimetry.