Microflora of the human gastrointestinal tract

Abstract

The human body plays host to a large and diverse group of microbial inhabitants. The intestinal system is certainly no exception. Extending from the esophagus to the anus, the human gut provides varying environments in which microorganism can exist and often thrive. Obtaining samples of these microbes to examine can be difficult, and much of what is known about the human gut has been learned from studying other animals. Among the most common genera of intestinal microbes inhabiting both humans and animal are Bacteroides, Clostridium and Bifidobacterium. Each of these genera exists within their own niche and has a symbiotic relationship with the digestive system and with each other. The gastrointestinal tract offers environments varying in pH, movement, and oxygen and nutrient availability, all of which affect which type of microbe may colonize an area. This composition of gut flora can also be affected by antibiotics which can lead to detrimental effects on the digestive system of the host. The host may also suffer should another part of the body become infected with an intestinal microbe. Despite their potential to cause harm, microorganisms play a crucial role in the human gut environment and have proven to be an integral component to human metabolism and healthy functioning.