Specific Co-Aggregation Inhibition by Arginine

A method of identifying a compound or composition that enhances the selective inhibition of co-aggregation of commensal and pathogenic bacteria by arginine or arginine oligomer, the method comprising the steps of:

• a) performing a bacterial aggregation test assay comprising co-culturing at least one commensal bacteria and at least on pathogenic bacteria in media that comprises arginine or arginine oligomer and a test compound or composition and measuring bacterial aggregation by assigning a score using Visual Co-aggregation Scoring at one or more time points;
• b) performing a bacterial aggregation control assay comprising co-culturing at least one commensal bacteria and at least on pathogenic bacteria in media that comprises arginine or arginine oligomer and is free of a test compound or composition and measuring bacterial aggregation by assigning a score using Visual Co-aggregation Scoring at the one or more time points;
• c) comparing the score of the bacterial aggregation test assay to the score of the bacterial aggregation control assay;
• wherein reduced score in the bacterial aggregation test assay compared to the score in the bacterial aggregation control assay indicates that the test compound or composition enhances inhibition of bacterial aggregation by arginine or arginine oligomer.

A method of identifying a compound or composition that enhances the selective inhibition of biofilm formation of commensal and pathogenic bacteria by arginine or an arginine oligomer, the method comprising the steps of:

• a) performing a biofilm formation test assay comprising co-culturing at least one commensal bacteria and at least on pathogenic bacteria in media that comprises arginine or an arginine oligomer and a test compound or composition and measuring biofilm formation at one or more time points;
• b) performing a biofilm formation control assay comprising co-culturing at least one commensal bacteria and at least on pathogenic bacteria in media that comprises arginine or an arginine oligomer and is free of a test compound or composition and measuring biofilm formation at the one or more time points;
• c) comparing the biofilm formation in the biofilm formation test assay to the biofilm formation in the biofilm formation control assay;
• wherein reduced biofilm formation in the biofilm formation test assay compared to the biofilm formation in the biofilm formation control assay indicates that the test compound or composition enhances inhibition of biofilm formation by arginine or an arginine oligomer.