Analisi proteomica della tolleranza al butanolo in Clostridium cellulovorans​

Biofuels are looked more and more as promising alternatives to traditional fossil sources of energy. Among biofuels, butanol represents one of the most interesting compounds, because of its encouraging properties. Moreover, butanol can be produced through biotechnological approach. The development of biorefineries lead to a second generation, whose feedstock are wastes indeed. Lignocellulosic wastes can be used as substrate for bacterial growth and their cellulosic component converted into biobutanol. C. cellulovorans is able to grow in this manner. Single genetic modification could allow remarkable amount of biobutanol to be produced by C. cellulovorans. However, development of a C. cellulovorans strain tolerant to butanol is also necessary for it to be used in butanol-producing biorefinery process. In this work a proteomic study was performed. The aim was identifying proteins that are overexpressed when C. cellulovorans is under butanol stress. After setting the proper concentration of butanol inducing stress on the bacterium without depleting totally its growth, upregulated proteins were identified by SWATH mass spectrometric analysis and divided regarding their COG categories. Several proteins seem to be involved in response to butanol stress, they are mainly involved in energetic functions, have chaperone-like activity or are involved in cell wall metabolism. In future, information obtained by the present study will be used for developing C. cellulovorans strains more tolerant to butanol by rational metabolic engineering, namely by up-regulating the genes identified in the present study.