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Published on: July 12, 2018
Efficient production of Trastuzumab Fab antibody fragments in Brevibacillus choshinensis expression system
Makoto Mizukami1, Hiromasa Onishi1, Hiroshi Hanagata1
1R & D Department, Higeta Shoyu Co., Ltd, 2-8 Chuo-cho, Choshi, Chiba, 288-8680, Japan.
Abstract:
The Brevibacillus expression system has been successfully employed for the efficient productions of a variety of recombinant proteins, including enzymes, cytokines, antigens and antibody fragments. Here, we succeeded in secretory expression of Trastuzumab Fab antibody fragments using B. choshinensis/BIC (Brevibacillus in vivocloning) expression system. In the fed-batch high-density cell culture, recombinant Trastuzumab Fab with amino-terminal His-tag (His-BcFab) was secreted at high level, 1.25 g/liter, and Fab without His-tag (BcFab) at ∼145 mg/L of culture supernatant. His-BcFab and BcFab were purified to homogeneity using combination of conventional column chromatographies with a yield of 10-13%. This BcFab preparation exhibited native structure and functions evaluated by enzyme-linked immunosorbent assay, surface plasmon resonance, circular dichroism measurements and size exclusion chromatography. To our knowledge, this is the highest production of Fab antibody fragments in gram-positive bacterial expression/secretion systems.
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