MANNURONAN C-5 EPIMERASE VARIANTS AND METHODS FOR THEIR IDENTIFICATION

摘要

The present invention provides an isolated nucleic acid molecule encoding a mannuronan C-5 epimerase that: (a) converts mannuronate-only alginate to alginate with an FG content of at least 0.8, an FGG content of at least 0.7 and an FMGM content of 0.4 or less; or (b) comprises: (i) a nucleotide sequence as set forth in SEQ ID NO: 1 or 2; (ii) a nucleotide sequence which has at least 95% sequence identity to SEQ ID NO: 1 or 2; (iii) a nucleotide sequence encoding a polypeptide comprising an amino acid sequence as set forth in SEQ ID NO: 3 or 4; (iv) a nucleotide sequence encoding a polypeptide comprising an amino acid sequence which has at least 95% sequence identity to an amino acid sequence as set forth in SEQ ID NO: 3 or 4; or (v) a complement of the nucleotide sequence of any one of (i) to (iv), wherein said epimerase results in alginate with an FG content of at least 0.8 when using mannuronate-only alginate as a substrate. Also provided is the epimerase encoded by the nucleic acid molecule and a screening method for characterising or determining epimerase activity.