Secretion of Bacillus alpha-amylase from yeast directed by glucoamylase I signal sequence of Saccharomyces diastaticus.
For the secretion of Bacillus stearothermophilus alpha-amylase from yeast, a recombinant plasmid pGAT17 was constructed by fusing B. stearothermophilus alpha-amylase structural gene in frame to the promoter and signal sequence of Saccharomyces diastaticus glucoamylase I gene (STA1). The secretion of the heterologous alpha-amylase from S. diastaticus transformed with pGAT17 was confirmed by the halo formation around colonies on selective starch agar medium. About 80% of the total alpha-amylase activity was detected in the extracellular culture medium. The secreted alpha-amylase was glycosylated and its molecular weight increased from 61 kDa to 75 kDa. The thermostability of the the glycosylated alpha-amylase was markedly enhanced, compared with that of the non-glycosylated enzyme from E. coli.
Kang
D O
DO
Microbial Chemistry Research Group, Korea Reseach Institute of Bioscience and Biotechnology, Taejon, Korea.
Hwang
I K
IK
Kim
B Y
BY
Ahn
S C
SC
Mheen
T I
TI
Ahn
J S
JS
Byun
S M
SM
D000595:Amino Acid Sequence; D001407:Bacillus / Q000201:enzymology*; D001483:Base Sequence; D015153:Blotting, Western / Q000379:methods; D005087:Glucan 1,4-alpha-Glucosidase / Q000235:genetics*; D008969:Molecular Sequence Data; D010957:Plasmids / Q000378:metabolism; D012440:Saccharomyces / Q000201:enzymology*; D015398:Signal Transduction / Q000235:genetics; D015003:Yeasts / Q000201:enzymology*; D000516:alpha-Amylases / Q000235:genetics / Q000378:metabolism*
D000516:alpha-Amylases; D005087:Glucan 1,4-alpha-Glucosidase