A. Miyauchi et al., Pilot scale production of a recombinant human epidermal growth factor, secreted by Bacillus brevis, using expanded bed adsorption, J IND MIC B, 21(4-5), 1998, pp. 208-214
Citations number
28
Categorie Soggetti
Biotecnology & Applied Microbiology
Journal title
JOURNAL OF INDUSTRIAL MICROBIOLOGY & BIOTECHNOLOGY
Recombinant Bacillus brevis which carried an expression plasmid encoding th
e human epidermal growth factor (EGF) gene on a cryptic high-copy number pl
asmid, pHT926, extracellularly produced EGF in its biologically active form
at a concentration of over 1.5 g L-1 in the culture broth in a 30-L jar fe
rmenter. The culture broth also contained some other EGF compounds, which m
ainly consisted of oligomeric and polymeric forms with disulfide bonds. We
developed a simple purification method for EGF, without prior cell removal
from the culture broth, comprising cation exchange expanded bed adsorption
followed by ultrafiltration with UF 10000 and 3000 membranes. The EGF compo
unds were efficiently separated from the EGF in its native form in the expa
nded bed adsorption step. With this purification method, only EGF in its na
tive form was recovered from the culture broth, with a yield of nearly 80%,
and 90% purity. This efficient and economic system has made it possible to
use EGF as a pharmaceutical in the livestock industry.