Category:LBSP: Difference between revisions

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==Sphingomyelin and Phosphoethanolamine ceramide==
{{Twocolumn|
In mammalian cells, the major headgroup of ceramides is phosphocholine (producing sphingomyelin), or complex polysaccharides (glycosphingolipids). There are three types of spingomyelin (SM) synthase (SMS1, SMS2, SMSr) and the latter produce ceramide phosphoethanolamine (CPE), whose biochemical function is yet unknown.
In ''Drosophila'' (fruitfly), the headgroup of ceramides is either phosphoethanolamine or complex polysaccharides, and completely lacks sphingomyelin. It has its own CPE synthase, not homologous to SM synthases.
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動物細胞ではセラミドの頭部にホスホコリン(スフィンゴミエリン SM ができる)、または複雑な糖鎖がつく。SM合成酵素には3種類あり、そのうちの2種はホスホエタノールアミンのついたセラミド CPE を合成する。
ショウジョウバエでは、セラミド頭部にホスホエタノールアミンか複雑な糖鎖がつき、スフィンゴミエリンは持たない。独自のCPE合成酵素があり、SM合成酵素とは相同性もない。
}}
;Mammalian SM synthase family
: ceramide + phosphatidylcholine &larr;&rarr; sphingomyelin + 1,2-diacylglycerol
: ceramide + phosphatidylethanolamine &larr;&rarr; PE-ceramide + 1,2-diacylglycerol
;Fruitfly CPE synthase
: ceramide + CDP-ethanolamine &larr;&rarr; PE-ceramide + CMP


==GIPC==
==GIPC==

Revision as of 01:39, 26 November 2015

Long-chain bases

Long-chain base (LCB or sphingoid base) is a 2-aminoalkane (or alkene) 1,3-diol with 2R, 3R stereochemistry (D-erythro for dihydroxy LCB and D-ribo for trihydroxy LCB). Major types are listed in the following Table. Animals usually contain LCB of length 18 (d18:1) and a little amount of d20:1. In yeast (S. cerevisiae), the predominant LCB is 4-hydroxysphinganine (t18:0)[1]. In higher plants, six LCB are major( (8E/Z)-d18:1, (8E/Z)-t18:1, (4E,8E/Z)-d18:2) with little d18:0 and t18:0. This means (4E/Z)-d18:1 is absent in plants. Insects contain LCB of shorter chains, e.g. d14:1 and d16:1.

長鎖塩基(またはスフィンゴイド塩基)は 2-アミノアルカン(またはアルケン) 1,3-ジオールを指す(立体化学はジヒドロキシLCBがD-エリスロ、トリヒドロキシLCBがD-リボ型)。代表的なものは以下のとおり。動物は通常、鎖長18のLCBを持ち (d18:1)、少量の d20:1 がある。イースト(パン酵母)で主要なLCBは t18:0 になる。高等植物では 6 種の LCB、(8E/Z)-d18:1, (8E/Z)-t18:1, (4E,8E/Z)-d18:2と、少量のd18:0, t18:0が見られる。(4E/Z)-d18:1 は見られない。昆虫は短い炭素鎖のスフィンゴイド塩基、例えば d14:1, d16:1 を持つ。

Major Sphingoid

Name Symbol Abbreviation Note
sphingosine = (4E)-sphingenine
(4E)-2-amino-octadec-4-ene-1,3-diol
d18:1 So Major in mammals
sphinganine = dihydrosphingosine
2-amino-octadecane-1,3-diol
d18:0 Sa or DHSo Lacking the trans-double bond of sphingosine
4-hydroxysphinganine = phytosphingosine
2-amino-octadecane-1,3,4-triol
t18:0 Phyto Major in yeast (S. cerevisiae)
6-hydroxysphingosine
(4E)-2-amino-octadec-4-ene-1,3,6-triol
6-t18:1 Found in skin

Notation

d18:1  h, d or t stands for single, double, or triple hydroxy groups, respectively.
18 is the carbon chain length.
1 is the number of unsaturated bonds (double bonds).
  1. Yeast is an exceptional case. Many fungi contain a (4,8)-diunsaturated, 9-methyl-branched LCB.

Ceramides

The word ceramide (Cer) basically refers to all N-acyl-sphingoid bases, but most representative one is N-acylsphingosines. The conjugated fatty acids are often 16 to 26 carbon chains, but ceramides in skin may contain >30 carbon chains.

セラミドという言葉は基本的に N-アシルスフィンゴイド塩基を指すが、最も代表的なものは N-アシルスフィンゴシンである。結合する脂肪酸の炭素長は16から26だが、皮膚のセラミドには長さが30以上の場合もある。

Composition

Species Glycosylceramide Glycosyl inositol phosphoceramide (GIPC)
Fatty acid Long chain base References Fatty acid Long chain base References
Plants h16:0 - h26:0
h16:1 - h26:1
h16:0
VLCFA
d18:2Δ4E8E/Z
d18:2Δ4E8E/Z
d18:1Δ8E/Z
t18:1Δ8E/Z
[1][2]
[1][2]
[1]
[1][2]
hVLCFA
h14:0 - h26:0
h20:1 - h26:1
t18:1Δ8E/Z
t18:1Δ8E/Z, t18:0
t18:1Δ8E/Z, t18:0
[1]
[3]
[1][3]
Fungi h16:0 - h18:0
h16:1 - h18:1
9-methyl d18:2Δ4E,8E
9-methyl d18:2Δ4E,8E
[4][2]
[4][2]
h24:0 - h26:0
h24:1 - h26:1
h16:0 - h26:0
t18:0
t18:0
t18:0, t20:0
[4]
[2]
[2][3]
  1. 1.0 1.1 1.2 1.3 1.4 1.5 Markham JE, Lynch DV, Napier JA, Dunn TM, Cahoon EB. Plant sphingolipids: function follows form. Curr Opin Plant Biol. 2013 16: 350-7. doi: 10.1016/j.pbi.2013.02.009.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Warnecke D, Heinz E..Recently discovered functions of glucosylceramides in plants and fungi. Cell Mol Life Sci. 2003 60:919-41.doi: 10.1007/s00018-003-2243-4.
  3. 3.0 3.1 3.2 Buré C, Cacas JL, Mongrand S, Schmitter JM. Characterization of glycosyl inositol phosphoryl ceramides from plants and fungi by mass spectrometry. Anal Bioanal Chem. 2013 doi: 10.1007/s00216-013-7130-8.
  4. 4.0 4.1 4.2 Nimrichter L, Rodrigues ML. Fungal glucosylceramides: from structural components to biologically active targets of new antimicrobials. Front Microbiol. 2011 2:212. doi: 10.3389/fmicb.2011.00212.


Sphingomyelin and Phosphoethanolamine ceramide

In mammalian cells, the major headgroup of ceramides is phosphocholine (producing sphingomyelin), or complex polysaccharides (glycosphingolipids). There are three types of spingomyelin (SM) synthase (SMS1, SMS2, SMSr) and the latter produce ceramide phosphoethanolamine (CPE), whose biochemical function is yet unknown. In Drosophila (fruitfly), the headgroup of ceramides is either phosphoethanolamine or complex polysaccharides, and completely lacks sphingomyelin. It has its own CPE synthase, not homologous to SM synthases.

動物細胞ではセラミドの頭部にホスホコリン(スフィンゴミエリン SM ができる)、または複雑な糖鎖がつく。SM合成酵素には3種類あり、そのうちの2種はホスホエタノールアミンのついたセラミド CPE を合成する。 ショウジョウバエでは、セラミド頭部にホスホエタノールアミンか複雑な糖鎖がつき、スフィンゴミエリンは持たない。独自のCPE合成酵素があり、SM合成酵素とは相同性もない。

Mammalian SM synthase family
ceramide + phosphatidylcholine ←→ sphingomyelin + 1,2-diacylglycerol
ceramide + phosphatidylethanolamine ←→ PE-ceramide + 1,2-diacylglycerol
Fruitfly CPE synthase
ceramide + CDP-ethanolamine ←→ PE-ceramide + CMP

GIPC

Glycosyl inositol phosphoceramides (GIPCs) were historically referred to as 'phytoglycolipids' (PGLs), although they are not plant-specific.[1][2] PGL was defined as inositolceramide with hexosamine, and its head-group without hexosamine was called ceramide phosphate polysaccharide (CPPS). The term GIPC was later introduced to cover them.

In LipidBank, we classify GIPC into four types:

  1. P2 series: Glucosamine next to inositol (Fungi and Protista)
  2. P3 series: Glucuronic acid next to inositol (Plant)
  3. P4 series: Mannose next to inositol (Fungi)
  4. P5 series: Others
  5. (P1 series is sphingomyelin and phosphoethanolamine ceramide.)

糖イノシトールセラミドリン酸 (GIPC) は歴史的にはフィト糖脂質 (PGL) として発見されたが、植物に特異な物質ではない。PGL はセラミドリン酸糖鎖 (CPPS) とよばれる構造の末端にヘキソサミンがつく構造とされ、後に GIPC と呼ばれるようになった。

LipidBankではGIPCを4つに分類している。

  1. イノシトールの次がグルコサミン (原生動物と菌類)
  2. イノシトールの次がグルクロン酸 (植物)
  3. イノシトールの次がマンノース (菌類)
  4. その他

  1. Carter HE, Celmer WD, Galanos DS, Gigg RH, Lands EM, Law JH, Mueller KL, Nakayama T, Tomizawa HH, Weber E. 1958. Biochemistry of the sphingolipides. X. Phytoglycolipide, a complex phytosphingosine-containing lipide from plant seeds. Journal of the American Oil Chemists Society 35: 335–343
  2. Carter HE, Brooks S, Gigg RH, Strobach DR, Suami T. 1964. Biochemistry of the sphingolipids. XVI. Structure of phytoglycolipid. Journal of Biological Chemistry 239: 743–746

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