Background: The fermentation conditions of recombinant maltose-binding protein fused to neutrophil-activating protein (rMBP-NAP) of Helicobacter pylori were optimized from Escherichia Coli TB1 with varying medium, inoculum age and size, time, inducer, pH and temperature in batch fermentation.

Results: It was revealed that the optimal conditions for the production of rMBP-NAP in shake flask were as follows: M9 medium (with 3% yeast extract powder added), the inoculum age of 19 h, the inoculum size of 6%, the initial pH of 6.6, temperature at 37ºC and 0.7 mmoL/L IPTG inducted 21 h in a 50 mL/250 mL shake flask. The recombinant protein yield was increased from 59 to 592 mg/L after optimization. Fermentation process conducted in a 10 L fermenter with similar conditions could get 30 g/L wet cell and 1.738 g/L soluble protein with rMBP-NAP expression level of 11.9%.