PRODUCTION AND USE OF BACTERIAL HISTAMINE
A method is provided of selecting specific probiotic lactic acid bacteria producing histamine and the use of such strains for beneficial effects for mammals. The method includes selecting a lactic acid bacterial strain for use in the local production of histamine in a mammal, and further comprises screening bacteria for the presence of an active histidine operon and selecting a strain which has an active histidine operon and is capable of producing histamine. Preferably said strain is selected for its ability to produce histamine at a level of greater than 250 pg/ml. The present invention further provides products comprising the strains obtainable by the selection methods of the invention for use in the local production of histamine in a mammal, in particular for use in the treatment or prophylaxis of inflammatory conditions.
1 . A method of selecting a lactic acid bacterial strain for use in the local production of histamine in a mammal, wherein said method comprises screening bacteria for the presence of an active histidine operon and selecting a lactic acid bacterial strain which has an active histidine operon and is capable of producing histamine.
2 . The method of claim 1 , wherein said lactic acid bacterial strain is a strain of Lactobacillus reuteri.
3 . The method of claim 1 , further comprising selecting said lactic acid bacterial strain for its ability to produce histamine at a level of greater than 300 ng/ml.
4 . The method of claim 2 , wherein said lactic acid bacterial strain is a strain of Lactobacillus reuteri.
5 . A method of treatment and/or prophylaxis of an inflammatory condition, comprising providing a lactic acid bacterial strain having an active histidine operon and capable of producing histamine.
6 . The method of claim 5 , wherein the inflammatory condition is selected from the group consisting of colitis, inflammatory bowel disease, irritable bowel syndrome, diverticulosis, gingivitis and vaginitis.
7 . The method of claim 5 , further comprising the administration of at least one further therapeutic or nutritional agent to the mammal.
8 . The method of claim 7 , wherein said further therapeutic or nutritional agent comprises histidine or a histidine analog, an appropriate carbon source which supports the production of histamine by said strain, or a combination thereof.
9 . The method of claim 8 , wherein the histidine or histidine analog is in the form of a histidine or histidine analog contained in a foodstuff or a food supplement.
10 . The method of claim 8 , wherein the carbon source comprises glucose.
11 . A product for use in the local production of histamine in a mammal comprising cells of a lactic acid bacterial strain obtained by the selection method according to claim 1 , wherein said lactic acid bacterial strain has an active histidine operon and is capable of producing histamine.
12 . The product of claim 11 , wherein the local production of histamine is in the GI tract, GU tract, oral cavity, lungs, airways, or on the skin of said mammal.
13 . The product of chum 11 , wherein said mammal is a human.
14 . The product of claim 11 , wherein said lactic acid bacterial strain is a strain of Lactobacillus reuteri.
15 . The product of claim 13 , wherein the local production of histamine is in the GI tract, GU tract, oral cavity, lungs, airways, or on the skin of said mammal.
16 . The product of claim 13 , wherein said lactic acid bacterial strain is a strain of Lactobacillus reuteri.
17 . The product of claim 11 , wherein said lactic acid bacterial strain is Lactobacillus reuteri 6475.
18 . The product of claim 11 , further comprising at least one additional component selected from the group consisting of an appropriate carbon source which supports the production of histamine by said strain, a source of histidine or histidine analog, and a combination thereof.
19 . The product of claim 18 , wherein said histidine or histidine analog is in the form of a histidine or histidine analog contained in a foodstuff or a food supplement.
20 . The product of claim 18 , wherein said carbon source comprises glucose.