N-terminal domain of Chondroitin polymerase functions as a GalNAc transferase. Chondroitin polymerase is a two domain, bi-functional protein. The N-terminal domain functions as a GalNAc transferase. The bacterial chondroitin polymerase catalyzes elongation of the chondroitin chain by alternatively transferring the GlcUA and GalNAc moiety from UDP-GlcUA and UDP-GalNAc to the non-reducing ends of the chondroitin chain. The enzyme consists of N-terminal and C-terminal domains in which the two active sites catalyze the addition of GalNAc and GlcUA, respectively. Chondroitin chains range from 40 to over 100 repeating units of the disaccharide. Sulfated chondroitins are involved in the regulation of various biological functions such as central nervous system development, wound repair, infection, growth factor signaling, and morphogenesis, in addition to its conventional structural roles. In Caenorhabditis elegans, chondroitin is an essential factor for the worm to undergo cytokinesis and cell division. Chondroitin is synthesized as proteoglycans, sulfated and secreted to the cell surface or extracellular matrix.

Glycosyltransferase family A (GT-A) includes diverse families of glycosyl transferases with a common GT-A type structural fold. Glycosyltransferases (GTs) are enzymes that synthesize oligosaccharides, polysaccharides, and glycoconjugates by transferring the sugar moiety from an activated nucleotide-sugar donor to an acceptor molecule, which may be a growing oligosaccharide, a lipid, or a protein. Based on the stereochemistry of the donor and acceptor molecules, GTs are classified as either retaining or inverting enzymes. To date, all GT structures adopt one of two possible folds, termed GT-A fold and GT-B fold. This hierarchy includes diverse families of glycosyl transferases with a common GT-A type structural fold, which has two tightly associated beta/alpha/beta domains that tend to form a continuous central sheet of at least eight beta-strands. The majority of the proteins in this superfamily are Glycosyltransferase family 2 (GT-2) proteins. But it also includes families GT-43, GT-6, GT-8, GT13 and GT-7; which are evolutionarily related to GT-2 and share structure similarities.

Glycosyl transferase family 2. Diverse family, transferring sugar from UDP-glucose, UDP-N-acetyl- galactosamine, GDP-mannose or CDP-abequose, to a range of substrates including cellulose, dolichol phosphate and teichoic acids.

CESA_like is the cellulose synthase superfamily. The cellulose synthase (CESA) superfamily includes a wide variety of glycosyltransferase family 2 enzymes that share the common characteristic of catalyzing the elongation of polysaccharide chains. The members include cellulose synthase catalytic subunit, chitin synthase, glucan biosynthesis protein and other families of CESA-like proteins. Cellulose synthase catalyzes the polymerization reaction of cellulose, an aggregate of unbranched polymers of beta-1,4-linked glucose residues in plants, most algae, some bacteria and fungi, and even some animals. In bacteria, algae and lower eukaryotes, there is a second unrelated type of cellulose synthase (Type II), which produces acylated cellulose, a derivative of cellulose. Chitin synthase catalyzes the incorporation of GlcNAc from substrate UDP-GlcNAc into chitin, which is a linear homopolymer of beta-(1,4)-linked GlcNAc residues and Glucan Biosynthesis protein catalyzes the elongation of beta-1,2 polyglucose chains of Glucan.

Glycosyltransferase, GT2 family [Carbohydrate transport and metabolism].

Crystalstructure of chondroitin polymerase from Escherichia coli strain K4 (K4CP) complexed with UDP-GlcUA and UDP [Escherichia coli],2Z86_B Crystal structure of chondroitin polymerase from Escherichia coli strain K4 (K4CP) complexed with UDP-GlcUA and UDP [Escherichia coli],2Z86_C Crystal structure of chondroitin polymerase from Escherichia coli strain K4 (K4CP) complexed with UDP-GlcUA and UDP [Escherichia coli],2Z86_D Crystal structure of chondroitin polymerase from Escherichia coli strain K4 (K4CP) complexed with UDP-GlcUA and UDP [Escherichia coli]

Crystalstructure of chondroitin polymerase from Escherichia coli strain K4 (K4CP) complexed with UDP-GalNAc and UDP [Escherichia coli],2Z87_B Crystal structure of chondroitin polymerase from Escherichia coli strain K4 (K4CP) complexed with UDP-GalNAc and UDP [Escherichia coli]

dTDP-MAGNESIUMCOMPLEX OF SPSA FROM BACILLUS SUBTILIS [Bacillus subtilis],1H7Q_A dTDP-MANGANESE COMPLEX OF SPSA FROM BACILLUS SUBTILIS [Bacillus subtilis],1QG8_A Native (Magnesium-Containing) Spsa From Bacillus Subtilis [Bacillus subtilis],1QGQ_A Udp-manganese Complex Of Spsa From Bacillus Subtilis [Bacillus subtilis],1QGS_A Udp-Magnesium Complex Of Spsa From Bacillus Subtilis [Bacillus subtilis]

Crystalstructure of S. aureus TarS in complex with UDP-GlcNAc [Staphylococcus aureus],5TZE_E Crystal structure of S. aureus TarS in complex with UDP-GlcNAc [Staphylococcus aureus],5TZI_C Crystal structure of S. aureus TarS 1-349 [Staphylococcus aureus],5TZJ_A Crystal structure of S. aureus TarS 1-349 in complex with UDP-GlcNAc [Staphylococcus aureus],5TZJ_C Crystal structure of S. aureus TarS 1-349 in complex with UDP-GlcNAc [Staphylococcus aureus],5TZK_C Crystal structure of S. aureus TarS 1-349 in complex with UDP [Staphylococcus aureus]

Crystalstructure of S. aureus TarS [Staphylococcus aureus],5TZ8_B Crystal structure of S. aureus TarS [Staphylococcus aureus],5TZ8_C Crystal structure of S. aureus TarS [Staphylococcus aureus]

Chondroitin synthase OS=Escherichia coli OX=562 GN=kfoC PE=1 SV=1

Chondroitin synthase OS=Pasteurella multocida (strain Pm70) OX=272843 GN=fcbD PE=3 SV=1

Uncharacterized glycosyltransferase RC0461 OS=Rickettsia conorii (strain ATCC VR-613 / Malish 7) OX=272944 GN=RC0461 PE=3 SV=1

Uncharacterized glycosyltransferase RF_0543 OS=Rickettsia felis (strain ATCC VR-1525 / URRWXCal2) OX=315456 GN=RF_0543 PE=3 SV=1

Uncharacterized glycosyltransferase RBE_0706 OS=Rickettsia bellii (strain RML369-C) OX=336407 GN=RBE_0706 PE=3 SV=1