Final answer:
Non-lactose fermenting bacteria, such as Salmonella, Shigella, Yersinia, and certain species of Bacteroides, can be found in the colon. These bacteria have diverse roles in digestion, vitamin production, and immune function, and they help prevent the colonization of pathogenic bacteria.
Step-by-step explanation:
Non-lactose fermenting bacteria that can be found in the colon include Salmonella spp., Shigella spp., Yersinia pestis, and some species of Bacteroides. These bacteria are part of the normal microbiota of the human colon and play important roles in digestion, the production of vitamins, and immune function. They can also prevent pathogenic bacteria from colonizing the large intestine. For example, Bacteroides species can help maintain the balance of the gut microbiome and prevent secondary infections.