Breaking down barriers: construction of a hybrid heterochiral membrane

Promotie

Breaking down barriers: construction of a hybrid heterochiral membrane

Promovendus drs.ing. MF (Melvin) Siliakus
Promotor prof.dr. J (John) van der Oost
Copromotor dr. SWM (Servé) Kengen
Organisatie Wageningen University, Laboratory of Microbiology
Datum

vr 4 november 2016 11:00 tot 12:30

Locatie Auditorium, building number 362
Generaal Foulkesweg 1
362
6703 BG Wageningen
0317-483592

Summary

Life on earth can be divided into three domains, the Eukarya, Archaea and Bacteria. The last two groups are at first glance very similar, but have enough essential differences to divide them into separate domains. Due to differences in the chemical structure of the membrane lipids, the Archaea and the Bacteria are able to survive under different conditions. Archaea, for example, are more resistant to extreme conditions, such as low pH, a high temperature or the presence of solvents. The presumption is therefore that archaeal membranes are more robust than bacterial membranes. In this study, we therefore engineered the enzymes for the assembly of archaeal lipids into the bacterium Escherichia coli, in the hope that a mixed membrane would be formed with an improved stability. The constructed E.coli was indeed found to possess a mixed membrane with a surprisingly high amount of archaeal lipids (28%). Although these adjustment led to severe morphological changes, the cells were found to have indeed more robust properties on exposure to heat, cold, and butanol. More stable E. coli cells are of interest for industrial applications, where often extreme conditions are used.