SAPONIN-DIGESTING ENZYMES, GENES THEREOF AND SOYASAPOGENOL B MASS PRODUCTION SYSTEM

摘要

A protein which comprises a 638 (II), 633 (IV), or 618 (VI) residue amino acid sequence, given in the specification, a protein with not less than50 % homology with (II), (IV) or (VI), and saponin-digesting activity, and a protein based on the amino acid sequence but with some amino acids deleted, inserted or added, is new. Independent claims are also included for: (1) a polynucleotide encoding the novel protein; (2) a polynucleotide chosen from: (a) a polynucleotide containing a 1917 (I), 1902 (III) or 1857 (V) base pairs, respectively; (b) a polynucleotide containing base sequence having not less than 70 % homology with that in (a) and encoding a protein with saponin-digesting activity; (c) a polynucleotide containing a base sequence derived from that in (a) but with some bases deleted, substituted, inserted or added and encoding a protein with saponin-digesting activity; and (d) a polynucleotide hybridizable with the base sequence in (a) under stringent conditions and encoding a protein with saponin-digesting activity; (3) a recombinant vector containing the polynucleotide of (1) or (2); (4) a host transformed with the recombinant vector of (3); (5) a process for producing the novel protein by culturing the host of (4) before collecting the product; and (6) producing soyasapogenol B by using a protein obtained by culturing the host, or by applying any of the proteins, to decompose a glycoside with soyasapogenol B as aglycone.