BACTERIAL CHAPERONES INCREASE THE PRODUCTION OF SOLUBLE HUMAN TNF-ALPHA IN ESCHERICHIA-COLI

Bacterial chaperones were coexpressed to enhance the production of sol uble human TNF-alpha and its low-toxicity mutant in Escherichia coil. In the absence of chaperones, about 65% of wild-type TNF and 35% of mu tant TNF having a deletion of N-terminal 7 amino acids and substitutio ns of Leu29-->Ser, Ser52-->lle and Tyr56-->Phe, were produced as a sol uble form. In the presence of overproduced chaperones, most of wild-ty pe and mutant TNF (>95%) were produced as a soluble form, indicating t hat GroEL and GroES chaperones promote folding and assembly of trimeri c TNF-alpha. Bacterial chaperones could be useful in the production of TNF-alpha and its variants as well as other proteins with biological importance.