The study of peptidoglycan-binding proteins frequently requires in vitro binding assays, in which the isolated peptidoglycan used as a substrate must be carefully quantified. Here, we describe an easy and sensitive assay for peptidoglycan quantification based on a modified Nelson-Somogyi reducing sugar assay. We report the response of this assay to different common sugars and adapt its use to peptidoglycan samples subjected to acid hydrolysis. This method showed better sensitivity than the peptidoglycan quantification method based on the acid detection of diaminopimelic acid. The method described in this work, besides being valuable in the characterization of peptidoglycan-binding proteins, is also useful for the quantification of reducing monosaccharides or polysaccharides after acid or hydrolysis.
Keywords: acid hydrolysis; cell wall; cell wall binding; hydrolyse acide; hydrolyse du peptidoglycane; liaison à la paroi cellulaire; paroi cellulaire; peptidoglycan hydrolysis; peptidoglycan quantification; quantification des sucres; quantification du peptidoglycane; sugar quantification.