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 26343315  68 LHVAIVCAGYNSSREIITLTKSLLFYR 94
Cdd:cd06431   1 IHVAIVCAGYNASRDVVTLVKSVLFYR 27

LARGE catalytic domain has closest homology to GT8 glycosyltransferase involved in lipooligosaccharide synthesis; The catalytic domain of LARGE is a putative glycosyltransferase. Mutations of LARGE in mouse and human cause dystroglycanopathies, a disease associated with hypoglycosylation of the membrane protein alpha-dystroglycan (alpha-DG) and consequent loss of extracellular ligand binding. LARGE needs to both physically interact with alpha-dystroglycan and function as a glycosyltransferase in order to stimulate alpha-dystroglycan hyperglycosylation. LARGE localizes to the Golgi apparatus and contains three conserved DxD motifs. While two of the motifs are indispensible for glycosylation function, one is important for localization of th eenzyme. LARGE was originally named because it covers approximately large trunck of genomic DNA, more than 600bp long. The predicted protein structure contains an N-terminal cytoplasmic domain, a transmembrane region, a coiled-coil motif, and two putative catalytic domains. This catalytic domain has closest homology to GT8 glycosyltransferase involved in lipooligosaccharide synthesis.

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gi 26343315  68 LHVAIVCAGYNSSREIITLTKSLLFYR 94
Cdd:cd06431   1 IHVAIVCAGYNASRDVVTLVKSVLFYR 27

LARGE catalytic domain has closest homology to GT8 glycosyltransferase involved in lipooligosaccharide synthesis; The catalytic domain of LARGE is a putative glycosyltransferase. Mutations of LARGE in mouse and human cause dystroglycanopathies, a disease associated with hypoglycosylation of the membrane protein alpha-dystroglycan (alpha-DG) and consequent loss of extracellular ligand binding. LARGE needs to both physically interact with alpha-dystroglycan and function as a glycosyltransferase in order to stimulate alpha-dystroglycan hyperglycosylation. LARGE localizes to the Golgi apparatus and contains three conserved DxD motifs. While two of the motifs are indispensible for glycosylation function, one is important for localization of th eenzyme. LARGE was originally named because it covers approximately large trunck of genomic DNA, more than 600bp long. The predicted protein structure contains an N-terminal cytoplasmic domain, a transmembrane region, a coiled-coil motif, and two putative catalytic domains. This catalytic domain has closest homology to GT8 glycosyltransferase involved in lipooligosaccharide synthesis.

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gi 26343315  68 LHVAIVCAGYNSSREIITLTKSLLFYR 94
Cdd:cd06431   1 IHVAIVCAGYNASRDVVTLVKSVLFYR 27