In May 2011, researchers from the European Molecular Biology Laboratory in Meyerhofstrasse published a research in which they proposed division of intestinal flora into three enterotypes. Shortly after that, already in August 2011, a team of researchers from the University of Pennsylvania classified existing enterotypes to specified diet in which they occur. The discovery was added to the list of the Top Scientific Discoveries of 2011 by The Science Magazine.

In fact, human body is not on its own but it has about 10 trillion friends about whom we do not think every day. Our helpers are bacteria in our gut. Despite the variety of species and large number of microorganisms, it was possible to name three groups of the most common bacteria in our intestines.

Intestinal flora do not only help to defend organism against pathogenic bacteria, but also in delivering vitamin K, which is involved in the synthesis of coagulation factors, vitamin H and many more. Furthermore, it stimulates the immune system and helps in the digestion of certain foods. Unfortunately, it can also cause opportunistic infections.

The researchers obtained DNA from samples of intestinal flora and compared them with existing bacterial gene sequences. The place which was the most interesting for the scientists was the 16S ribosomal-RNA-encoding gene. By analyzing the results they were able to determine the most common bacterial species in a given sample and create a division into enterotypes.

Enterotype 1 in which the most common bacteria is Bacterioides. The main source of energy for this type of fermentation are sugars and proteins. People who eat mainly meat and products such as mayonnaise, cream, cheese, and other containing large amounts of saturated fats have this enterotype.

Enterotype 2: Prevotella. This type is characterized by a high ability to degrade glycoproteins, mucin in particular. The bacteria of this type is the most common in people who eat mostly simple sugars and in Vegetarian.

Enterotype 3, in which the most common bacteria is Ruminococcus, is the most common type. It was also found that a high incidence of bacterial Akkermansia occur at this profile. These bacteria have the ability to obtain energy by fermentation of proteins, distribution of mucins and sugars. It often occurs in people who consume a lot of alcohol and foods rich in unsaturated fats. Enterotypes also differ in terms of which vitamin they produce. Type1 and Type2 produces biotin, riboflavin, panthenol, ascorbic acid and thiamine. Typ3 produces extra folic acid.

Despite attempts, any association between the occurrence of enterotypes and gender, age or body mass index (BMI) was not found. Probably the existence of the group is dependent on other factors. Among the factors are a person’s immune system, hereditary factors, or the pH of the digestive tract. The existence of such factors may support attempts to change the type of enterotype by changing the diet. In all subjects of sample profile of bacteria did not change.

Owing to the efforts of scientists we can identify three different types of intestinal flora in humans. Also we can link each enterotype to specific diet or assign them to specific vitamin they produce. Unfortunately, we still do not know what causes that different people have certain enterotype, and it is probably due to a small number of researches. It seems that studies concerning this subject can bring a lot of interesting conclusions which can find practical application in medicine.

Written by: Maciej Jakuszko, Jerzy Bednarski, Michał Hys, Adam Lebiediew

Source:
1.http://www-huber.embl.de/pub/pdf/nature09944.pdf
2.http://www.nature.com/nature/journal/v474/n7353/full/nature10187.html
3.http://news.sciencemag.org/sciencenow/2011/09/your-gut-bacteria-are-what-you-e.html
4.http://www.sciencemag.org/content/334/6052/105


Want to know more about bacteria? Watch on medtube.net “Pseudomembranous Colitis”