Putative catalytic NodB homology domain of uncharacterized BH1302 protein from Bacillus halodurans and its bacterial homologs. This family is represented by a putative polysaccharide deacetylase BH1302 from Bacillus halodurans. Although its biological function is unknown, BH1302 shows high sequence homology to the catalytic NodB homology domain of Streptococcus pneumoniae polysaccharide deacetylase PgdA (SpPgdA), which is an extracellular metal-dependent polysaccharide deacetylase with de-N-acetylase activity toward a hexamer of chitooligosaccharide N-acetylglucosamine, but not shorter chitooligosaccharides or a synthetic peptidoglycan tetrasaccharide. Both BH1302 and SpPgdA belong to the carbohydrate esterase 4 (CE4) superfamily. This family also includes many uncharacterized bacterial polysaccharide deacetylases.

Catalytic NodB homology domain of Clostridium thermocellum acetylxylan esterase and its bacterial homologs. This family is represented by Clostridium thermocellum acetylxylan esterase (CtAXE, EC 3.1.1.72), a member of the carbohydrate esterase 4 (CE4) superfamily. CtAXE deacetylates O-acetylated xylan, a key component of plant cell walls. It shows no detectable activity on generic esterase substrates including para-nitrophenyl acetate. It is specific for sugar-based substrates and will precipitate acetylxylan, as a consequence of deacetylation. CtAXE is a monomeric protein containing a catalytic NodB homology domain with the same overall topology and a deformed (beta/alpha)8 barrel fold as other CE4 esterases. However, due to differences in the topography of the substrate-binding groove, the chemistry of the active center, and metal ion coordination, CtAXE has different metal ion preference and lacks activity on N-acetyl substrates. It is significantly activated by Co2+. Moreover, CtAXE displays distinctly different ligand coordination to the metal ion, utilizing an aspartate, a histidine, and four water molecules, as opposed to the conserved His-His-Asp zinc-binding triad of other CE4 esterases.

Catalytic NodB homology domain of rhizobial NodB-like proteins. This family belongs to the large and functionally diverse carbohydrate esterase 4 (CE4) superfamily, whose members show strong sequence similarity with some variability due to their distinct carbohydrate substrates. It includes many rhizobial NodB chitooligosaccharide N-deacetylase (EC 3.5.1.-)-like proteins, mainly from bacteria and eukaryotes, such as chitin deacetylases (EC 3.5.1.41), bacterial peptidoglycan N-acetylglucosamine deacetylases (EC 3.5.1.-), and acetylxylan esterases (EC 3.1.1.72), which catalyze the N- or O-deacetylation of substrates such as acetylated chitin, peptidoglycan, and acetylated xylan. All members of this family contain a catalytic NodB homology domain with the same overall topology and a deformed (beta/alpha)8 barrel fold with 6- or 7 strands. Their catalytic activity is dependent on the presence of a divalent cation, preferably cobalt or zinc, and they employ a conserved His-His-Asp zinc-binding triad closely associated with the conserved catalytic base (aspartic acid) and acid (histidine) to carry out acid/base catalysis. Several family members show diversity both in metal ion specificities and in the residues that coordinate the metal.

Catalytic NodB homology domain of uncharacterized bacterial polysaccharide deacetylases. This family includes many uncharacterized bacterial polysaccharide deacetylases. Although their biological function still remains unknown, members in this family show high sequence homology to the catalytic NodB homology domain of Streptococcus pneumoniae polysaccharide deacetylase PgdA (SpPgdA), which is an extracellular metal-dependent polysaccharide deacetylase with de-N-acetylase activity toward a hexamer of chitooligosaccharide N-acetylglucosamine, but not shorter chitooligosaccharides or a synthetic peptidoglycan tetrasaccharide. Like SpPgdA, this family is a member of the carbohydrate esterase 4 (CE4) superfamily.

Peptidoglycan/xylan/chitin deacetylase, PgdA/CDA1 family [Carbohydrate transport and metabolism, Cell wall/membrane/envelope biogenesis].

ChainA, Glycoside Hydrolase, Family 11:clostridium Cellulosome Enzyme, Dockerin Type I:polysaccharide [Acetivibrio thermocellus],2C79_A Chain A, GLYCOSIDE HYDROLASE, FAMILY 11:CLOSTRIDIUM CELLULOSOME ENZYME, DOCKERIN TYPE I:POLYSACCHARIDE [Acetivibrio thermocellus]

Crystalstructure of the Xyl-CE4 domain of a multidomain xylanase from the hindgut metagenome of Trinervitermes trinervoides [uncultured bacterium]

ChainA, Predicted xylanase/chitin deacetylase [Caldanaerobacter subterraneus subsp. tengcongensis MB4]

Crystalstructure of the Bc1960 peptidoglycan N-acetylglucosamine deacetylase in complex with 4-naphthalen-1-yl-~{N}-oxidanyl-benzamide [Bacillus cereus ATCC 14579]

T48deacetylase [Arthrobacter sp. AW19M34-1],5LGC_A T48 deacetylase with substrate [Arthrobacter sp. AW19M34-1]

Peptidoglycan-N-acetylglucosamine deacetylase BC_3618 OS=Bacillus cereus (strain ATCC 14579 / DSM 31 / CCUG 7414 / JCM 2152 / NBRC 15305 / NCIMB 9373 / NCTC 2599 / NRRL B-3711) OX=226900 GN=BC_3618 PE=1 SV=1

Bifunctional xylanase/deacetylase OS=Pseudobutyrivibrio xylanivorans OX=185007 GN=xyn11A PE=1 SV=2

Peptidoglycan-N-acetylglucosamine deacetylase BC_1960 OS=Bacillus cereus (strain ATCC 14579 / DSM 31 / CCUG 7414 / JCM 2152 / NBRC 15305 / NCIMB 9373 / NCTC 2599 / NRRL B-3711) OX=226900 GN=BC_1960 PE=1 SV=1

Peptidoglycan-N-acetylglucosamine deacetylase OS=Streptococcus pneumoniae (strain ATCC BAA-255 / R6) OX=171101 GN=pgdA PE=1 SV=1

Peptidoglycan-N-acetylglucosamine deacetylase PgdA OS=Listeria monocytogenes serotype 1/2a (strain EGD / Mackaness) OX=1334565 GN=pgdA PE=1 SV=1