چكيده لاتين :
Recombinant human interferon alpha 2a (rhIFN alfa-2a) production and cell growth were monitored in a set of genetically modified E. coli strains (MSDI519, MSD1520, MSD 1521, MSD 1522, MSD 1523)
producing rhIFN 0.-2a. The growth was followed at OD 600 nm, changes in cell physiology were detected by pyrolysis mass spectrometry (PyMS) of cell biomass and recombinant protein production was determined by SDS-gel electrophoresis. The heat stress applied was minimal (50°C for 5 minutes) but the effects were detected in most of the strains. All the strains except MSD 1520 showed a significant increase in the quantity of the rhIFN alfa-2a secretion at 25 hour growth under the heat shock
condition, quantitated by the Bio-Rad Molecular analyst software, MultiAnalyst from the digital image of gels captured using a Fluor S image analysis system. In the main fermentation system at T7
hour, only MSD 1523 showed an increase in the rhIFN alfa-2a secretion under the heat shock condition, at T8 hour MSD 1520 and MSD 1523 had an increased rhIFN alfa-2a secretion, and at TI0 MSD 1521
and MSD 1522 had an increased rhIFN alfa-2a secretion under the heat shock condition. The PCCV ordination diagrams obtained from the PyMS result showed, a considerable effect of heat shock on the MSD 1519 strain at T5 hour. For the other strains, the result largely agreed with both the growth curves and the rhIFN alfa-2a production that had a limited effect on E. coli cultures. The increase of temperature in the main fermentation during the log phase of the bacterial culture during rhIFN alfa-2a expression depends on the strain specificity. This situation could definitely lead to over expression of the gene and higher intracellular accumulation of rhIFN alfa-2a molecule.