Colonic Bacteroides

Colon Bacteroides spp., peptostreptococci, Clostridium, E. coli, Klebsiella, enterococci, Enterobacter, and many others 10 -10 loM o ... 

Catabolism of Mucopolysaccharides, Plant Gums, and Maillard Products by Human Colonic Bacteroides... 

The mixture of complex carbohydrates which enters the human colon includes not only plant cell wall polysaccharides but also a variety of other types of carbohydrate such as mucopolysaccharides (from dietary meat or host secretions), plant gums which are added to foods as emulsifiers, and Maillard reaction products. Some strains of colonic Bacteroides which can degrade plant cell wall polysaccharides can also degrade one or more of these other types of carbohydrates. 

ELFOUL L, RABOT s, KHELIFA N, QUINSAC A, DUGUAY A and RiMBAULT A (2001) Formation of allyl isothiocyanate from sinigrin in the digestive tract of rats monoassociated with a hiunan colonic strain of Bacteroides thetaiotaomicron , FEMS Microbiol Lett, 197 99-103. 

Creation of a suitable environment for the growth of colonic microorganisms, such as Bacteroids, Eubacterium, and Enterobacteriaceae, among others ... 

Table 1.1). Out of the 400 distinct bacterial species in the colon, 30% of fecal isolates are of the genus Bacteroides. This phylogenetic group is characterized by a relatively high growth yield even at low rates, which enables it to compete successfully in this region of the intestine... 

The colon contains about 400 different species of anaerobic and aerobic bacteria.15 The most common anaerobes in the colon are Bifidobacterium spp., Eubacterium spp., Peptostreptococcus spp., Fusobacterium spp., and Bacteroides spp. The most common aerobe in the colon is Escherichia coli.16,17 Colonic bacteria are involved in the synthesis of B complex vitamins and a majority of vitamin K.18... 

The colon serves four major functions. They are 1) creation of a suitable environment for the growth of colonic microorganisms such as Bacteroids, Eubac-terium, and Enterobacteriaceae 2) storage reservoir of fecal contents 3) expulsion of the contents of the colon at a suitable time and 4) absorption of water and Na from the lumen, concentrating the fecal content, and secretion of K+ and HCOs . The active secretion of K+ is stimulated by mineralocorticoids. 

The bacteria colonizing the small bowel (such as Escherichia coli and Bacteroides species) deconjugate and dehydroxylate bde salts, leading to conjugated bde salt deficiency, which causes fat malabsorption. Bacterial metabolism of vitamin B12 may also occur, leading to vitamin B,2 deficiency. The clinical symptoms of bacterial overgrowth are abdominal pain, diarrhea, and steatorrhea. ... 

Antenucci, R., Palmer, J. K. Enzymatic degradation of a-and (3-cyclodextrins by bacteroides of the human colon. J. Agric. Food Chem. 1984, 32, 1316-1321. 

The lower female genital tract generally is colonized by a large munber of aerobic and anaerobic bacteria. Anaerobes may number 10 organisms per milliliter and often include lactobaciUi, eubacte-ria, Clostridia, anaerobic streptococci, and less frequently, Bacteroides frag il is. Aerobic bacteria most often are streptococci and Staphylococcus epidermidis, and these may munber 10 organisms per milbliter. 

An emerging concept is that a balance in the GI tract normally exists among the mucosal epithelium, the normal gut flora, and the immune response. Some data suggest that colonic bacteria may either initiate or perpetuate the inflammation of IBD, and specific bacterial antigens in the pathogenesis of Crohn s disease. Thus, certain bacterial strains may be either pro- (e.g., Bacteroides) or antiinflammatory (e.g., Lactobacillus), prompting attempts to manipulate the colonic flora in patients with IBD. Traditionally, antibiotics have been used to this end, most prominently in Crohn s disease. More recently, probiotics have been used to treat specific chnical situations in IBD. 

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