What is the purpose of bacteria in the intestines?
Its primary function is to salvage energy from carbohydrate not digested in the upper gut. Intestinal bacteria also have a role in the synthesis of vitamins B and K and the metabolism of bile acids, other sterols and xenobiotics. The colonic microflora are also responsive to diet.
The many bacteria that inhabit the large intestine can further digest some material, creating gas. Bacteria in the large intestine also make some important substances, such as vitamin K, which plays an important role in blood clotting.
- The major function of the large intestine is to absorb water from the remaining indigestible food matter and transmit the useless waste material from the body.
- The harmless strains are part of the normal microbiota of the gut, and can benefit their hosts by producing vitamin K2, and preventing colonization of the intestine with pathogenic bacteria, having a symbiotic relationship. E. coli is expelled into the environment within fecal matter.
- It plays a fundamental role in human digestion by breaking down sugar polymers to simple glucose. Human cells do the same thing, but, until recently, no one expected gut bacteria to have such a large repertoire of enzymes that break down complex sugars.
Composition and Distribution of the Intestinal Microflora. The intestinal microflora is a complex ecosystem containing over 400 bacterial species. Anaerobes outnumber facultative anaerobes. The flora is sparse in the stomach and upper intestine, but luxuriant in the lower bowel.
- The significance of urine culture with mixed flora. Siegman-Igra Y. Urine cultures that contain more than one organism are usually considered contaminated. The frequency with which such growth truly represents mixed infection is unknown.
- The vaginal flora are the bacteria that live inside the vagina. The normal vaginal flora are dominated by various lactobacillus species. Lactobacilli help to keep the vagina healthy by producing lactic acid, hydrogen peroxide, and other substances that inhibit the growth of yeast and other unwanted organisms.
- The symptoms may include:
- loss of appetite.
- nausea and vomiting.
- abdominal pains and cramps.
- blood in your stools.
Although there are many types of harmful bacteria, the body contains many forms of helpful or “friendly” bacteria in the intestinal tract. Known as intestinal flora, these organisms consist of bacteria, fungi, protozoa and yeast, and have specific purposes that help the body.
- Normal flora can be found in many sites of the human body including the skin (especially the moist areas, such as the groin and between the toes), respiratory tract (particularly the nose), urinary tract, and the digestive tract (primarily the mouth and the colon).
- The small intestine contains small finger-like projections of tissue called villi which increase the surface area of the intestine and contain specialized cells that transport substances into the bloodstream. Although these villi do not aid in the digestion of nutrients, they do help with nutrient absorption.
- We will be focusing on prokaryotic, as well as eukaryotic, organisms that reside in the large intestine. The bacteria that will be discussed include the following: Lactobacillus, Bifidobacterium, Methanogens, Sulfate reducing bacteria, Bacteroides, Enterococcus, Escherichia coli, and Clostridium.
Updated: 2nd October 2019