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.

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gi 1779434631   4 HNGWWKNTSTPRRWLDAMR 22
Cdd:cd04189   213 VTGWWKDTGTPEDLLEANR 231

G1P_TT_long represents the long form of glucose-1-phosphate thymidylyltransferase; This family is the long form of Glucose-1-phosphate thymidylyltransferase. Glucose-1-phosphate thymidylyltransferase catalyses the formation of dTDP-glucose, from dTTP and glucose 1-phosphate. It is the first enzyme in the biosynthesis of dTDP-L-rhamnose, a cell wall constituent and a feedback inhibitor of the enzyme.There are two forms of Glucose-1-phosphate thymidylyltransferase in bacteria and archeae; short form and long form. The long form, which has an extra 50 amino acids c-terminal, is found in many species for which it serves as a sugar-activating enzyme for antibiotic biosynthesis and or other, unknown pathways, and in which dTDP-L-rhamnose is not necessarily produced.The long from enzymes also have a left-handed parallel helix domain at the c-terminus, whereas, th eshort form enzymes do not have this domain. The homotetrameric, feedback inhibited short form is found in numerous bacterial species that produce dTDP-L-rhamnose.

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gi 1779434631   4 HNGWWKNTSTPRRWLDAMR 22
Cdd:cd04189   213 VTGWWKDTGTPEDLLEANR 231

G1P_TT_long represents the long form of glucose-1-phosphate thymidylyltransferase; This family is the long form of Glucose-1-phosphate thymidylyltransferase. Glucose-1-phosphate thymidylyltransferase catalyses the formation of dTDP-glucose, from dTTP and glucose 1-phosphate. It is the first enzyme in the biosynthesis of dTDP-L-rhamnose, a cell wall constituent and a feedback inhibitor of the enzyme.There are two forms of Glucose-1-phosphate thymidylyltransferase in bacteria and archeae; short form and long form. The long form, which has an extra 50 amino acids c-terminal, is found in many species for which it serves as a sugar-activating enzyme for antibiotic biosynthesis and or other, unknown pathways, and in which dTDP-L-rhamnose is not necessarily produced.The long from enzymes also have a left-handed parallel helix domain at the c-terminus, whereas, th eshort form enzymes do not have this domain. The homotetrameric, feedback inhibited short form is found in numerous bacterial species that produce dTDP-L-rhamnose.

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                  ....*....|....*....
gi 1779434631   4 HNGWWKNTSTPRRWLDAMR 22
Cdd:cd04189   213 VTGWWKDTGTPEDLLEANR 231