Identification of sucA, Encoding β-Fructofuranosidase, in Rhizopus microsporus.

NBRC 32995 was found to hydrolyze fructooligosaccharides (FOS), as well as sucrose, almost completely into monosaccharides through the production of sufficient amounts of organic acids, indicating that the complete hydrolysis of FOS was caused by the secretion of β-fructofuranosidase from fungal cells. Thus, the gene, encoding a β-fructofuranosidase, was amplified by degenerate PCR, and its complete nucleotide sequence was determined. The total length of the gene was 1590 bp, and the SucA protein of NBRC 32995 belonged to clade VIa, which also contains and is closely related to Saccharomycotina, a subdivision of the Ascomycota.