A Polysaccharide Deacetylase Homologue, PdaA, in Bacillus subtilis Acts as an N-Acetylmuramic Acid Deacetylase In Vitro

摘要

A polysaccharide deacetylase homologue, PdaA, was determined to act as an N-acetylmuramic acid deacetylase in vitro. Histidine-tagged truncated PdaA (with the putative signal sequence removed) was overexpressed in Escherichia coli cells and purified. Measurement of deacetylase activity showed that PdaA could deacetylate peptidoglycan treated with N-acetylmuramoyl-l-alanine amidase CwlH but could not deacetylate peptidoglycan treated with or without dl-endopeptidase LytF (CwlE). Reverse-phase high-performance liquid chromatography and mass spectrometry (MS) and MS-MS analyses indicated that PdaA could deacetylate the N-acetylmuramic acid residues of purified glycan strands derived from Bacillus subtilis peptidoglycan.