翻訳と辞書 Words near each other ・ Hex Hall ・ Hex Hector ・ Hex Heroes ・ Hex key ・ Hex map ・ Hex Rally ・ Hex River ・ Hex River Mountains ・ Hex River Pass ・ Hex River Poort Pass ・ Hex River Tunnels ・ Hex sign ・ Hex – The Legend of the Towers ・ Hex'Air ・ Hex; Or Printing in the Infernal Method ・ HEXA ・ Hexaarylbiimidazole ・ Hexabenzocoronene ・ Hexaborane ・ Hexaborane(12) ・ Hexabranchus ・ Hexabranchus morsomus ・ Hexabromobenzene ・ Hexabromocyclododecane ・ Hexacene ・ Hexacentrus ・ Hexachaeta ・ Hexachaeta abscura ・ Hexachaeta amabilis ・ Hexachaeta bifurcata Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク HEXA ： ウィキペディア英語版 HEXA Hexosaminidase A (alpha polypeptide), also known as HEXA, is an enzyme that in humans is encoded by the ''HEXA'' gene, located on the 15th chromosome. Hexosaminidase A and the cofactor GM2 activator protein catalyze the degradation of the GM2 gangliosides and other molecules containing terminal N-acetyl hexosamines. Hexosaminidase A is a heterodimer composed of an alpha subunit (this protein) and a beta subunit. The alpha subunit polypeptide is encoded by the ''HEXA'' gene while the beta subunit is encoded by the ''HEXB'' gene. Gene mutations in the gene encoding the beta subunit (HEXB) often result in Sandhoff disease; whereas, mutations in the gene encoding the alpha subunit (HEXA, this gene) decrease the hydrolysis of GM2 gangliosides, which is the main cause of Tay–Sachs disease. == Function == Even though the alpha and beta subunits of hexosaminidase A can both cleave GalNAc residues, only the alpha subunit is able to hydrolyze GM2 gangliosides. The alpha subunit contains a key residue, Arg-424, which is essential for binding the N-acetyl-neuramanic residue of GM2 gangliosides. The alpha subunit can hydrolyze GM2 gangliosides because it contains a loop structure consisting of the amino acids: Gly-280, Ser-281, Glu-282, and Pro-283. The loop is absent in the beta subunit, but it serves as an ideal structure for the binding of the GM2 activator protein (GM2AP) in the alpha subunit. A combination of Arg-424 and the amino acids that cause the formation of the loop allow the alpha subunit to hydrolyze GM2 gangliosides into GM3 gangliosides by removing the N-acetylgalactosamine (GalNAc) residue from GM2 gangliosides. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「HEXA」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.