Abstract: The present disclosure relates to gastrointestinal (Gl) tract microbiome detection and manipulation devices, systems, and methods. The determination of antimicrobial susceptibility of a micro-organism within the gastrointestinal tract involves identifying an antimicrobial agent that inhibits the growth of the micro-organism has been disclosed, which has been obtained from a sample having been removed from an ingestible device that retrieved the sample from the Gl tract of the subject. A test to identify the micro-organism can be included. Treatment methods related to small intestinal bacterial overgrowth (SIBO), a SIBO-related condition, or symptomology suggestive of SIBO in a subject in need thereof, involving orally administering an effective amount of a pharmaceutical formulation comprising an antimicrobial agent to the subject are also disclosed.

Abstract: In certain embodiments, constructs are provided that selectively/preferentially inhibit and/or kill Clostridium difficile. In certain embodiments the constructs comprise a peptide that binds C. difficile attached directly or through an amino acid or a linker to an antimicrobial peptide.