Antibiotic-resistant bacterial infections often occur in patients with chronic inflammatory intestinal conditions, such as inflammatory bowel disease, and in patients who have taken antibiotics for a long time. Gram-negative bacteria such as Enterobacteriaceae are a common cause of these infections and have few treatment options. Fecal microbiota transplants have shown promise to curb some of these infections, but their composition varies between batches and they aren't always successful.