A fermentation process for the production of P50 from Serratia marcescens
Abstract
Serratia marcescens is an opportunistic gram-negative enteric bacterium isolated from the respiratory and urinary tracts in humans. Among the secreted S. marcescens extracellular proteins, the P50 protein is produced in large amounts and plays an important role in the pathogenesis of this organism. To produce this protein, a fermentation process was studied. First, in a 2³ factorial experimental design different culture supplement as tryptone, yeast extract and peptone, were studied. In 4 L bioreactors the influence of aeration rate and agitation speed over the P50 production were studied in a 3² experimental design. Finally, the optimal growth conditions were established (28 °C, 400 rpm and 0.5 vvm), at this scale, 9.0 ODu/mL, 62% level of P50 protein expression and 220 mg/L as the higher P50 volumetric production, were obtained.
