A-Acetylmuramoyl-L-alanine Amidases

A -Acetylmuramoyl-L-alanine Amidases.—A sensitive fluorometric assay for A-acetylmuramoyl-L-alanine amidase uses as the substrate B. subtilis cell walls labelled with fluorescamine.  

L-Seryl/L-Threonyl-a-D-2-acetamido-2-deoxygaIactosidases.—A glycosidase that is able to act on the 0-glycosidic linkage between 2-acetamido-2-deoxy-a-D-galacto-pyranosyl and serine or threonine residues in glycopeptides has been detected in a commercial preparation of Clostridium perfringens (C. welchii) and in culture filtrates of Diplococcus pneumoniae 

A purified extracellular enzyme from D. pneumoniae specifically hydrolysed 2-acetamido-2-deoxy-3-0-j8-D-galactopyranosyl-o -D-glucopyranosyl units attached to either threonine or serine residues.  

Miscellaneous.—ewcto-j3-D-2-Acetamido-2-deoxyglucanase H from Streptomyces griseus completely hydrolysed the unit A (D-mannose - 2-acetamido-2-deoxy-D-glucose) glycopeptides of thyroglobulin, but did not act on a modified unit B (a complex heteropolysaccharide) free from side-chains. This and other evidence indicated that this enzyme and an eni/o-/8-D-2-acetamido-2-deoxy-glucanase D from Diplococcus pneumoniae have different specificities the 

Nakamura and K. Horikoshi, Agric. and Biol. Chem. Japan), 1976, 40, 935. 

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