Patent ID: 7666632

Claim:
A method for preparing alternan and/or fructose, wherein (a) a saccharose-containing solution is contacted with an alternansucrase protein under conditions permitting the conversion of saccharose into alternan and/or fructose, wherein the protein is encoded by a nucleic acid molecule selected from the group consisting of (i) a nucleic acid molecule encoding at least the mature form of a protein comprising the amino acid sequence indicated in SEQ ID NO:2 or the amino acid sequence which is encoded by the insert of plasmid pAlsu-pSK within DSM 12666; (ii) a nucleic acid molecule comprising the nucleotide sequence indicated in SEQ ID NO:1 or the nucleotide sequence within plasmid pAlsu-pSK within DSM 12666 or the corresponding ribonucleotide sequence; (iii) a nucleic acid molecule encoding a Leuconostoc mesenteroides protein comprising an amino acid sequence, the amino acid sequence of which has a homology of at least 90% to the amino acid sequence indicated in SEQ ID NO:2; and (iv) an enzymatically active fragment of any of the above; and (b) alternan and/or fructose is/are isolated from the solution, wherein the protein of (a) shows no contamination with another Leuconostoc mesenteroides protein and catalyzes the conversion of sucrose to alternan.