Scale-down effect on the extracellular proteome of Escherichia coli: correlation with membrane permeability and modulation according to substrate heterogeneities

摘要: Protein leakage is induced in well-mixed fed-batch bioreactor by comparison with cultures carried out scale-down conditions. This effect attributed to a progressive increase of cell membrane permeability and the synthesis several outer-membrane components allowing cope substrate limitation commonly found high density culture. A comparative analysis protein has thus been performed bioreactors devices. The extracellular proteome E.coli investigated 2D-gel electrophoresis identified subsequent MALDI-TOF analysis. On 110 picked spots, 67 proteins have sub-localisation molecular function these determined. majority was composed periplasmic (64 %) confirming fact that involved cultures. About 50 % this transport binding proteins. Furthermore, more abundant spots on gel corresponded porin transporters. In particular, OmpC be very abundant. Moreover, two-dimensional differential in-gel (2D-DIGE), significant differences observed culture systems. Indeed, since signal alleviated kind apparatus, lowered as shown flow cytometry. conditions, less