Category:LBSC: Difference between revisions

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| colspan="4" |  (weight %) From: Yamakawa T, Nishimura S. Cerebroside composition in animal brain. Jpn J Exp 36:101, 1966
| colspan="4" |  (weight %) From: Yamakawa T, Nishimura S. "Cerebroside composition in animal brain" Jpn J Exp 1966;36:101 PMID 5297247
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====Fatty acid composition of bovine brains====
====Fatty acid composition of bovine brains====

Revision as of 02:21, 10 May 2016


Upper classes: LB LBS

Cerebrosides

LBS01.png

Sugar = Glucose / Galactose

Monoglycosylceramides (or cerebrosides) are glycosphingolipids where a single sugar is attached to the ceramide structure. Especially, glucopyranose-attached Glucosylceramide (GlcCer) and galactopyranose-attached Galactosylceramide (GalCer) are widely observed in all kingdoms, and therefore we do not register them in LipidBank [1]. Instead, we summarize their distribution with bibliographic references for biological species[2].

モノグリコシルセラミド (またはセレブロシド) はセラミドに糖が1個エステル結合したスフィンゴ糖脂質です。特にグルコース(ピラノース型)が結合したグルコシルセラミド (GlcCer) とガラクトース(ピラノース型)が結合したガラクトシルセラミド (GalCer) は生物界に広く分布するので、データベース中には掲載せず、ここに解説と生物種ごとの報告例を掲載します。

GlcCer

GlcCer is widely observed not only in Animal, Plant or Fungi kingdoms, but also in Protozoa Kingdom. Ceramide structures (hydrocarbon chain length, the number and position of double bonds, existence of hydroxy and other modification groups) may vary, and become complex especially in Plant and Fungi Kingdoms, and Protostomia [3]. In Animal Kingdom, GlcCer is the basic structure for different derivative series such as Globo, Lacto, and Ganglio Series. In Protostomia, GlcCer is the major ceramide in its nerve tissue, e.g. shrimp brain [4], and the amide-linked fatty acids do not contain hydroxy groups (In plant, fatty acids are mostly α-hydroxylated and/or ω9-desaturated). In Mammalia (of Deuterostomia), GlcCer is major in the spleen, blood, and skin.

Gaucher's disease is an inborn metabolic disorder in which GlcCer accumulates in the liver and spleen because of the deficiency of the enzyme glucocerebrosidase to dissociate glucose from the ceramide structure.

GlcCerは系統発生的にみると動物の各組織に広く分布するだけでなく、植物界や菌界、原生生物界にも含まれます。セラミド構造(炭化水素の鎖長、二重結合の数と位置、水酸基の有無、修飾基の有無など)の組み合わせは多岐にわたり、特に植物界や菌界、旧口動物のセラミドは複雑です。動物界において、GlcCerはさまざまな糖鎖を持つ糖脂質の基本構造になり、グロボ系列、ラクト系列、ガングリオ系列などが生成されます。旧口(前口)動物の神経系にはGlcCerが多く含まれ(例えばエビ)、その脂肪酸に水酸基を含みません(植物にはα水酸化やω9不飽和の脂肪酸が多い)。後口動物の哺乳綱においては、脾臓、血液、皮膚などに多く含まれます。

先天性代謝異常症であるゴーシェ (Gaucher) 病ではGlcCerを分解するグルコセレブロシダーゼが欠損しており、肝臓や脾臓にGlcCerが蓄積します。

GalCer

GalCer has been observed in Eubacterial Domain, but not in Protozoa, Plant, or Fungi (except Ascomycota). It is widely observed in Animal Kingdom, but not in Ecdysozoa (cuticle-shedding animals) of Protostomia. Its ceramide structure differs widely as in GlcCer but not so complex as GlcCer in Plant and Fungi. GalCer is the basic structure for sulfatide (3-O-sulfogalactosylceramide or SM4) and Gala Series often found in Annelida (segmented worm). In Mammalia (of Deuterostomia), GalCer is major in the nerve tissue, especially myelin sheath, whose amido-linked fatty acids are hydroxylated at the C-2 position for more than 50%.

Krabbe disease (globoid cell leukodystrophy) is an inborn metabolic disorder in which a small amount of psychosine (galactosylsphingosine, i.e., the lyso form of GalCer) induces demyelination because of the deficiency of the enzyme galactosylceramidase [5]. α-GalCer, found from Porifera (marine sponge), in which galactose is α-bonded to ceramide (not the usual β-bond), uniquely binds to human or mouse NKT cells and is considered a potent anti-tumor agent.

GalCerは真正細菌に存在しますが、原生生物界、植物界、菌界(子嚢菌を除く)では報告がありません。動物界に広く分布しますが旧口動物である脱皮動物には確認されていません。セラミド構造は、GlcCerと同様に多様ですが、植物や菌類のGlcCerほど複雑ではありません。GalCerはスルファチド (3-O-硫酸化ガラクトシルセラミドまたはSM4) や環形動物門に多く含まれるガラ系列の基本構造です。

後口動物である哺乳綱では神経系、特にミエリン鞘にGalCerが多く含まれ、その脂肪酸の50%以上は、C2位が水酸化されています。

クラッベ病(グロボイド細胞ロイコジストロフィー; GLD)はガラクトシルセラミダーゼの欠損により微量のサイコシン(ガラクトシルスフィンゴシン、つまり GalCer のリゾ体)が蓄積して脱髄(ミエリンの破壊)を起こす遺伝性疾患です。また、海綿動物門に発見されたα-GalCerは、ガラクトースがセラミドに(通常のβでなく)α結合しており、ヒトやマウスのNKT細胞に特異的に結合し抗腫瘍効果がみられます。

  1. Cerebrosides with 2-amino-2-deoxy or 2-O-isoprenyl glycosyl moieties are found in spongia. See RX Tan & JH Chen (2003) The cerebrosides. Nat Prod Rep 20:509-534
  2. Itonori S, Sugita M. Glycophylogenetic Aspects of Lower Animals. in Comprehensive Glycoscience Vol.3, Biochemistry of glycoconjugate glycans. (J.P. Kamerling, ed.) Elsevier, Oxford (UK). pp. 253-84 (2007)
  3. Sphingoid base chain may terminate with an isopropyl group in spongia, annelida, echinodermata, and bacteria. Terminal isobutyl or sec-pentyl group has been found only in echinodermata. Methylated or cyclopropane-containing sphingoid base is found in spongia, echinodermata, protochordata, and fungi.
  4. Okamura N, Stoskopf M, Hendricks F, Kishimoto Y. (1985) Phylogenetic dichotomy of nerve glycosphingolipids. Proc Natl Acad Sci, 82:6779-6782
  5. GalCer accumulates in the kidney and not in nerve tissues. See Igisu et al. (1983) Biochem Biophys Res Commun 110:940-944; Igisu et al. (1983) Brain 106:405-417;Igisu & Suzuki (1984) J Neuropath Exp Neurol 43:22-36.

Cerebrosides in Mammals

Lipids in Heart Muscle

【生化学ハンドブックの文献情報を入れる】

Lipids in Rat Testis

Cerebroside and Sulfatide Ratio in Animal Brain

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