A bacterial strain AM7, isolated from soil and identified as Bacillus circulans, produced two kinds of novel cyclic oligosaccharides. The cyclic oligosaccharides were produced from amylose using a culture supernatant of the strain as the enzyme preparation. The major product was a cyclomaltopentaose cyclized by an α-(1→6)-linkage, cyclo-{→6)-α-D-Glcp-(1→4)-α-D-Glcp-(1→4)-α-D-Glcp-(1→4)-α-D-Glcp-(1→4)-α-D-Glcp-(1→}. The other minor product was cyclomaltohexaose cyclized by an α-(1→6)-linkage, cyclo-{→6)-α-D-Glcp-(1→4)-α-D-Glcp-(1→4)-α-D-Glcp-(1→4)-α-D-Glcp-(1→4)-α-D-Glcp-(1→4)-α-D-Glcp-(1→}. We propose the names isocyclomaltopentaose (ICG5) and isocyclomaltohexaose (ICG6) for these novel cyclic maltooligosaccharides having one α-(1→6)-linkage. ICG5 was digested by α-amylase derived from Aspergillus oryzae, cyclomaltodextrin glucanotransferase (CGTase) from Bacillus stearothermophilus, and maltogenic α-amylase. On the other hand, ICG6 was digested by CGTase from B. stearothermophilus and B. circulans, and maltogenic α-amylase. This is the first report of enzymatically produced cyclomaltopentaose and cyclomaltohexaose, which have an α-(1→6)-linkage in their molecules
cyclomaltopentaose, Bacillus circulans
NCBI PubMed ID: 16545346Publication DOI: 10.1016/j.carres.2006.02.028Journal NLM ID: 0043535Publisher: Elsevier
Correspondence: h-watanabe@hayashibara.co.jp
Institutions: Amase Institute, Hayashibara Biochemical Laboratories, Inc., Amase minami-machi, Japan
Methods: 13C NMR, 1H NMR, NMR-2D, TLC, ESI-MS, HPLC, enzymatic digestion, acetylation, LC-MS, methylation analysis, reduction, DEPT
Found