The process microbiolu00e0gico of cultivation for human prolactin obtenu00c7u00e7o

摘要

The process microbiolu00e0gico cultivation to obtenu00c7u00e7o human prolactin. It is described the process of cultivation in the bioreactor with short duration for obtaining high biomass of bacteria Escherichia coli and efficient secretion of prolactin, human in space periplu00e1smico bacterial. We used a strain of Escherichia coli transformed by the insertion of a plasmid called sym pl DsbA - hPRL.This plasmid is characterized by having the gene corresponding to the signal peptide followed by bacterial DsbA cDNA of human prolactin; the gene responsible for resistance to the antibiotic ampicillin and lambda PL promoter whose activation occurs by temperature increase.In this process has not been used the repressive CLTS, a thermo sensitive protein that is usually used for inhibiting the operation of the lambda PL promoter during growth on the 30th.The cultivation process has mainly three stages: in the first stage, the growth is carried out without the continued addition of nutrients (cultivation "batch"), in the second stage occurs continued addition of nutrients and carbohydrate (fed batch cultivation ") and the last step is performed to the activation, C Aracterizada by increase of temperature and the addition of nutrients and carbohydrate.This fermentation process is of short duration, with an average of 20 hours, with the final biomass corresponding to optical density of approximately 40 a600nm (units optical absorbance in 600nm) and expression of the order of 1 109 G hPRL / ml / a600.It is described an alternative process of growing exclusively in "batch", with a duration of only 10 hours and yields useful in the order of 12 109 G hPRL / ml of culture medium.