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.

polysaccharide deacetylase family sporulation protein PdaB. This model describes the YbaN protein family, also called PdaB and SpoVIE, of Gram-positive bacteria. Although ybaN null mutants have only a mild sporulation defect, ybaN/ytrI double mutants show drastically reducted sporulation efficiencies. This synthetic defect suggests the role of this sigmaE-controlled gene in sporulation had been masked by functional redundancy. Members of this family are homologous to a characterized polysaccharide deacetylase; the exact function this protein family is unknown. [Cellular processes, Sporulation and germination]

Catalytic NodB homology domain of uncharacterized bacterial glycosyl transferase, group 2-like family proteins. This family includes many uncharacterized bacterial proteins containing an N-terminal GH18 (glycosyl hydrolase, family 18) domain, a middle NodB-like homology domain, and a C-terminal GT2-like (glycosyl transferase group 2) domain. Although their biological function is unknown, members in this family contain a middle NodB homology domain that is similar to the catalytic domain of Streptococcus pneumoniae polysaccharide deacetylase PgdA (SpPgdA), 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. The presence of three domains suggests that members of this family may be multifunctional.

Catalytic NodB homology domain of Streptococcus pneumoniae peptidoglycan deacetylase PgdA, Bacillus subtilis BsYjeA protein, and their bacterial homologs. This family is represented by Streptococcus pneumoniae peptidoglycan GlcNAc deacetylase (SpPgdA), a member of the carbohydrate esterase 4 (CE4) superfamily. SpPgdA protects gram-positive bacterial cell wall from host lysozymes by deacetylating peptidoglycan N-acetylglucosamine (GlcNAc) residues. It consists of three separate domains: N-terminal, middle and C-terminal (catalytic) domains. The catalytic NodB homology domain is similar to the deformed (beta/alpha)8 barrel fold adopted by other CE4 esterases, which harbors a mononuclear metalloenzyme employing a conserved His-His-Asp zinc-binding triad closely associated with conserved catalytic base (aspartic acid) and acid (histidine) to carry out acid/base catalysis. The enzyme is able to accept GlcNAc3 as a substrate, with the N-acetyl of the middle sugar being removed by the enzyme. This family also includes Bacillus subtilis BsYjeA protein encoded by the yjeA gene, which is one of the six polysaccharide deacetylase gene homologs (pdaA, pdaB/ybaN, yheN, yjeA, yxkH and ylxY) in the Bacillus subtilis genome. Although homology comparison shows that the BsYjeA protein contains a polysaccharide deacetylase domain, and was predicted to be a membrane-bound xylanase or a membrane-bound chitooligosaccharide deacetylase, more recent research indicates BsYjeA might be a novel non-specific secretory endonuclease which creates random nicks progressively on the two strands of dsDNA, resulting in highly distinguishable intermediates/products very different in chemical and physical compositions over time. In addition, BsYjeA shares several enzymatic properties with the well-understood DNase I endonuclease. Both enzymes are active on ssDNA and dsDNA, both generate random nicks, and both require Mg2+ or Mn2+ for hydrolytic activity.

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

Structureof peptidoglycan deacetylase PdaC from Bacillus subtilis [Bacillus subtilis subsp. subtilis str. 168],6H8L_B Structure of peptidoglycan deacetylase PdaC from Bacillus subtilis [Bacillus subtilis subsp. subtilis str. 168]

Structureof peptidoglycan deacetylase PdaC from Bacillus subtilis - mutant D285S [Bacillus subtilis subsp. subtilis str. 168],6H8N_B Structure of peptidoglycan deacetylase PdaC from Bacillus subtilis - mutant D285S [Bacillus subtilis subsp. subtilis str. 168]

Crystalstructure of the Bc1960 peptidoglycan N-acetylglucosamine deacetylase from Bacillus cereus [Bacillus cereus ATCC 14579],4L1G_B Crystal structure of the Bc1960 peptidoglycan N-acetylglucosamine deacetylase from Bacillus cereus [Bacillus cereus ATCC 14579],4L1G_C Crystal structure of the Bc1960 peptidoglycan N-acetylglucosamine deacetylase from Bacillus cereus [Bacillus cereus ATCC 14579],4L1G_D Crystal structure of the Bc1960 peptidoglycan N-acetylglucosamine deacetylase from Bacillus cereus [Bacillus cereus ATCC 14579]

Crystalstructure of the Bc1960 peptidoglycan N-acetylglucosamine deacetylase in complex with 4-naphthalen-1-yl-~{N}-oxidanyl-benzamide [Bacillus cereus ATCC 14579],5O6Y_C Crystal structure of the Bc1960 peptidoglycan N-acetylglucosamine deacetylase in complex with 4-naphthalen-1-yl-~{N}-oxidanyl-benzamide [Bacillus cereus ATCC 14579],5O6Y_D Crystal structure of the Bc1960 peptidoglycan N-acetylglucosamine deacetylase in complex with 4-naphthalen-1-yl-~{N}-oxidanyl-benzamide [Bacillus cereus ATCC 14579]

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

Peptidoglycan-N-acetylmuramic acid deacetylase PdaC OS=Bacillus subtilis (strain 168) OX=224308 GN=pdaC PE=1 SV=1

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

Chitooligosaccharide deacetylase OS=Sinorhizobium fredii (strain NBRC 101917 / NGR234) OX=394 GN=nodB PE=3 SV=2