Gut microbiota have blood types as human

ABO blood group system was firstly recognized by Landsteiner in 1900[1].Since then,the antigens of the ABO system (A,B and H determinants,respectively)have been shown to encompass complex carbohydrate structures [2].A and B antigen were synthesized by the sequential action of glycosyltransferases,with A and B glycosyltransferases catalyzing the addition of N-acetylgalactosamine and D-galactose to precursor H antigen,respectively. Group O individuals lack such transferase enzymes and consequently continue to express the basic H structure only [3,4].It is determined that approximate 2million ABH glycan antigen sites are presented on each red blood cell [5].Additionally,the ABH antigens are widely expressed in other human ceils and tissues,including the sensory neurons,epithelium,the vascular endothelium and platelets [6].