Elastin-like protein production kinetics at different environmental conditions in Escherichia coli

Abstract

Elastomeric proteins are known by their great resilient properties being able to withstand significant deformations without rupture, returning to their original state when the stress is removed. In this family we find elastin like polymers (ELPs) that have the ability to undergo inverse temperature transition1 along with other smart behaviour properties. Furthermore, they present astonishing biocompatibility, making them ideal for a huge range of applications especially in health sciences. Ind this work we have studied the production of GAG220, and ELP composed by the monomer VPAVG, expressed by E. coli. Since GAG220 and the culture medium used were designed by us it is vital to understand the polymer kinetics formation profile in order to identify the peak of production. A set of experiments was planned comprising a screening of the production at different environmental conditions, namely incubation temperature, dissolved oxygen tension and primary carbon source concentration. The results indicated that a peak in the polymer production occurs at the desacceleration phase, showing that the biomass and polymer formation are directly related. Further incubation leads to a decrease in the amount of the polymer recovered which suggests either polymer degradation or cell leakage. Moreover, we have verified some relation between polymer production and dissolved oxygen available in the medium.