Two types of beta-fructofuranosidases from Aspergillus oryzae KB.
Aspergillus oryzae KB produces two types of beta-fructofuranosidases, F1 and F2. F1 produces 1-kestose, nystose, and fructosyl nystose from sucrose through its transfructosylation action. F2 hydrolyzes sucrose to glucose and fructose. N-Terminal amino acid sequences of the purified enzymes were DYNAAPPNLST for F1 and YSGDLRPQ for F2. Each enzyme encoding gene was identified in the genome of Aspergillus oryzae. Although the KB strain showed a higher production of F2 than F1 in a low sucrose liquid medium, F2 production gradually decreased, whereas F1 production increased with increasing sucrose concentration in the medium. Synthesis of F1 and F2 mRNAs analyzed on reverse-transcription polymerase chain reaction corresponded to individual enzymatic production. During liquid culture of the KB strain, F1 synthesizes fructooligosaccharides from sucrose through transfructosylation, and F2 gradually hydrolyzes it. In a highly concentrated sucrose medium, intake of sucrose into the KB strain was depressed by F1 through synthesis of transfer products, fructooligosaccharides.
Kurakake
Masahiro
M
Faculty of Life Science and Biotechnology, Department of Applied Biological Science, Fukuyama University, Sanzou, Gakuenchou 1 banchi, Fukuyama, Hiroshima 729-0292, Japan. kurakake@fubac.fukuyama-u.ac.jp
Ogawa
Kenji
K
Sugie
Motoki
M
Takemura
Akihiro
A
Sugiura
Kouji
K
Komaki
Toshiaki
T
D000595:Amino Acid Sequence; D001236:Aspergillus oryzae / Q000201:enzymology*; D005632:Fructose / Q000378:metabolism; D015870:Gene Expression; D005947:Glucose / Q000378:metabolism; D010446:Peptide Fragments / Q000737:chemistry; D012333:RNA, Messenger / Q000032:analysis; D013395:Sucrose / Q000378:metabolism; D014357:Trypsin / Q000378:metabolism; D043324:beta-Fructofuranosidase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D010446:Peptide Fragments; D012333:RNA, Messenger; D005632:Fructose; D013395:Sucrose; D043324:beta-Fructofuranosidase; D014357:Trypsin; D005947:Glucose