Microbial lysozyme for use in the treatment of irritable bowel syndrome or inflammatory bowel disease

1. A method of stopping, hindering, alleviating or treating Irritable Bowel Syndrome (IBS) or Inflammatory Bowel Disease (IBD), the method comprising administering to a human a composition comprising a microbial lysozyme, wherein the microbial lysozyme has activity against Lactobacillus johnsonii , and wherein the method reduces the amount of dead Lactobacillus johnsonii cells in the digestive tract of said human.

2. The method of claim 1 , wherein the microbial lysozyme stabilizes the healthy microbiota in the GI tract of the human and suppresses growth and/or intestinal colonization of bacterial pathogens in the human.

3. The method of claim 1 , wherein the composition comprising the microbial lysozyme is administered at a level of 0.1 ppm to 1000 ppm enzyme protein per kg of said composition.

4. The method of claim 1 , wherein the composition comprising the lysozyme is administered at a level of 1 to 200 mg enzyme protein per kg bodyweight of said human.

5. The method of claim 1 , wherein the microbial lysozyme comprises one or more domains selected from a GH24 domain and a GH25 domain.

6. The method of claim 1 , wherein the microbial lysozyme is selected from at least one of:

(a) a polypeptide having at least 50% sequence identity to SEQ ID NO: 1;

(b) a variant of SEQ ID NO: 1 wherein the variant has lysozyme activity and comprises one or more amino acid substitutions, and/or one or more amino acid deletions, and/or one or more amino acid insertions or any combination thereof in 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 ,14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions;

(c) a fragment of the polypeptide of (a) or (b) that has lysozyme activity wherein the fragment comprises at least 170 amino acids;

(d) a polypeptide having at least 50% sequence identity to SEQ ID NO: 4;

(e) a variant of SEQ ID NO: 4 wherein the variant has lysozyme activity and comprises one or more amino acid substitutions, and/or one or more amino acid deletions, and/or one or more amino acid insertions or any combination thereof in 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 ,14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions;

(f) a fragment of the polypeptide of (d) or (e) that has lysozyme activity wherein the fragment comprises at least 210 amino acids;

(g) a polypeptide having at least 50% sequence identity to SEQ ID NO: 15;

(h) a variant of SEQ ID NO: 15 wherein the variant has lysozyme activity and comprises one or more amino acid substitutions, and/or one or more amino acid deletions, and/or one or more amino acid insertions or any combination thereof in 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 ,14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 positions;

(i) a fragment of the polypeptide of (g) or (h) that has lysozyme activity wherein the fragment comprises at least 170 amino acids;

and combinations thereof.

7. The method of claim 1 , wherein the microbial lysozyme comprises an amino acid sequence selected from amino acids 1 to 208 of SEQ ID NO: 1, amino acids 1 to 245 of SEQ ID NO: 4, and amino acids 1 to 207 of SEQ ID NO: 15.

8. The method of claim 1 , wherein the composition comprising the microbial lysozyme is a food composition or pharmaceutical composition.

9. The method of claim 1 , wherein the composition comprising the microbial lysozyme is in the form of a powder, tablet, lozenge, effervescent tablet, capsule, emulsion, paste, individual sachet, chewing gum or oil drops.

10. The method of claim 1 , wherein the Irritable Bowel Syndrome (IBS) or Inflammatory Bowel Disease (IBD) is Crohn's disease and/or Ulcerative colitis.

11. The method of claim 1 , wherein said administering the composition comprising the microbial lysozyme increases the proportion of bacteria of genus Faecalibacterium in the microbiota of the GI tract.

12. The method of claim 1 , wherein the microbial lysozyme is a polypeptide having at least 90% sequence identity to the polypeptide of SEQ ID NO: 1.

13. The method of claim 1 , wherein the microbial lysozyme is a polypeptide having at least 90% sequence identity to the polypeptide of SEQ ID NO: 4.

14. The method of claim 1 , wherein the microbial lysozyme is a polypeptide having at least 90% sequence identity to the polypeptide of SEQ ID NO: 15.

15. The method of claim 1 , wherein the microbial lysozyme has a lysozyme activity against Lactobacillus johnsonii at 5 ppm that increases optical density (OD) measurement at 405 nm of at least 0.20 as determined by Method for the Determination of Lysozyme Activity Against Lactobacillus johnsonii.