Bacillus subtilis for producing N-acetylneuraminic acid and application thereof

Recombinant Bacillus subtilis, expressing glucosamine-6-phosphate-N-acetyltransferase, N-acetylglucosamine isomerase and N-acetylneuraminic acid synthase (NeuB), wherein the N-acetylneuraminic acid synthase (NeuB) is derived from Neisseria meningitidis;

• wherein the N-acetylneuraminic acid synthase has an amino acid sequence set forth as SEQ ID NO:1;
• wherein expression of coding genes of the glucosamine-6-phosphate-N-acetyltransferase, the N-acetylglucosamine isomerase and the N-acetylneuraminic acid synthase in the recombinant Bacillus subtilis is enhanced by promoters;
• and nucleotide sequences of the promoters are selected from SEQ ID NOs:17-26;
• wherein the glucosamine-6-phosphate-N-acetyltransferase has an amino acid sequence set forth as SEQ ID NO:3;
• and the N-acetylglucosamine isomerase has an amino acid sequence set forth as SEQ ID NO:5;
• wherein the recombinant Bacillus subtilis also expresses UDP-N-acetylglucosamine 2-epimerase (NeuC) and N-acetylglucosamine-6-phosphate-isomerase (NanE).