All-D Aβ (1-42) exhibits similar properites as the all-L Aβ. The peptide forms ion channels in lipid bilayers.

很多蛋白在細(xì)胞中非常容易被降解，或被標(biāo)記，進(jìn)而被選擇性地破壞。但含有部分D型氨基酸的多肽則顯示了很強(qiáng)的抵抗蛋白酶降解能力。

淀粉肽背景：β淀粉樣蛋白（Aβ或Abeta）是從淀粉樣前體蛋白加工而成的含有36–43個(gè)氨基酸的多肽。Aβ是與阿爾茲海默病相關(guān)的淀粉樣蛋白斑的成分。已有證據(jù)表明，Aβ是一個(gè)多功能肽，具有顯著的非病理性活性。Aβ是阿爾茲海默病患者腦中發(fā)現(xiàn)的沉積物的主要成分。在散發(fā)性阿爾茲海默病患者的腦中，Aβ的水平升高，造成腦血管病變和神經(jīng)毒性。Aβ蛋白是由β和γ分泌酶的連續(xù)作用而產(chǎn)生的。γ分泌酶產(chǎn)生Aβ肽的C末端，在APP的轉(zhuǎn)膜結(jié)構(gòu)域切割，可以產(chǎn)生許多36-43個(gè)氨基酸殘基長度的異構(gòu)體，最常見的異構(gòu)體是Aβ40和Aβ42。更長形式的Aβ在內(nèi)質(zhì)網(wǎng)中切割產(chǎn)生，而更短形式的Aβ在反面高爾基網(wǎng)中產(chǎn)生。

structure of Amyloid β-Peptide (1-40) (human)

淀粉樣蛋白肽的 定義淀粉樣蛋白 是絲狀蛋白質(zhì)沉積物，大小從納米到微米不等，并且由肽β鏈的平行或反平行排列形成的聚集的肽β折疊構(gòu)成。

結(jié)構(gòu)特征：使用固態(tài)NMR（SSNMR），與計(jì)算能量最小化過程結(jié)合，Tycko和合作者已經(jīng)提出從淀粉狀蛋白肽SS（Aß1-40）的40個(gè)殘基的形式形成的淀粉樣蛋白原纖維的結(jié)構(gòu)在pH 7.4和24 o C在靜止條件下。在這種結(jié)構(gòu)中，每個(gè)Aß1-40分子在原纖維的核心區(qū)域貢獻(xiàn)一對ß鏈，大約跨越殘基12-24和30-40。這些由回路25-29連接的鏈不是同一張ß-sheet的一部分，但參與同一原絲內(nèi)兩個(gè)不同的ß-sheets的形成。不同的Aß分子2、3至少從第9到39位殘基以平行排列和對齊的方式相互堆疊。通過調(diào)用其他實(shí)驗(yàn)約束，例如使用透射電子顯微鏡（TEM）觀察到的原絲直徑和單位質(zhì)量通過掃描透射電子顯微鏡（STEM）1、2測得的長度表明，單個(gè)原絲是由四個(gè)ß片組成的，它們之間的距離約為10Å。

作用模式：阿爾茨海默氏病（AD）是淀粉樣蛋白絲狀沉積物的結(jié)果，淀粉狀蛋白沉積物在分子水平上定義該疾病，發(fā)生在神經(jīng)周膜，軸突，樹突和神經(jīng)元末端，如神經(jīng)原纖維纏結(jié)（NFT），在細(xì)胞外神經(jīng)纖維中淀粉樣斑塊（APC），以及周圍的血管稱為淀粉樣嗜血性血管?。ˋCA）。淀粉樣蛋白沉積物顯然發(fā)生在發(fā)展NFT的神經(jīng)元末端區(qū)域。已經(jīng)表明，APC和ACA的主要成分已被證明是4.5kDa的淀粉樣蛋白，最初被稱為“β-蛋白”或“淀粉樣蛋白A4”，我們現(xiàn)在將其稱為“βA4”。

功能：鈣失調(diào)和膜破壞是可溶性淀粉樣蛋白低聚物普遍存在的神經(jīng)毒性機(jī)制：進(jìn)行了一項(xiàng)研究，以研究Ca 2+信號轉(zhuǎn)導(dǎo)可能參與淀粉樣蛋白誘導(dǎo)的細(xì)胞毒性，疾病相關(guān)淀粉樣蛋白（β，病毒，胰島淀粉樣蛋白）的均質(zhì)制劑制備了處于各種聚集狀態(tài)的多肽，聚谷氨酰胺和溶菌酶），并測試了它們對加載fluo-3的SH-SY5Y細(xì)胞的作用。寡聚形式的所有淀粉樣蛋白的應(yīng)用（0.6-6 µg / ml）迅速（約5 s）使細(xì)胞內(nèi)Ca 2+升高，而等量的單體和原纖維則沒有。細(xì)胞內(nèi)Ca 2+耗盡后，Abeta42低聚物引起的Ca 2+信號持續(xù)存在店，和小信號仍留在鈣2 + -游離介質(zhì)，指示從細(xì)胞外和細(xì)胞內(nèi)Ca貢獻(xiàn)2+源。膜對Ca 2+的滲透性增加不能歸因于內(nèi)源性Ca 2+通道的活化，因?yàn)榉磻?yīng)不受強(qiáng)力的Ca 2 +-通道阻滯劑鈷的影響。取而代之的是，觀察到Abeta42和其他低聚物引起陰離子熒光染料的快速細(xì)胞泄漏，這表明膜通透性普遍提高。導(dǎo)致的離子和分子通量失調(diào)可能為許多淀粉樣變性疾病中Ca 2+失調(diào)提供了由低聚物介導(dǎo)的毒性的常見機(jī)制。離子起著至關(guān)重要的作用，因?yàn)樗鼈兊目缒舛忍荻群軓?qiáng)，并且參與了細(xì)胞功能障礙和死亡。

2型糖尿病中的胰島淀粉樣蛋白和毒性低聚物假說： 2型糖尿?。═2DM）的特征是胰島素抵抗，胰島素分泌缺陷，β細(xì)胞量減少，β細(xì)胞凋亡增加和胰島淀粉樣蛋白。胰島淀粉樣蛋白源自胰島淀粉樣蛋白多肽（IAPP，胰島淀粉樣多肽），該蛋白是通過胰β細(xì)胞與胰島素共表達(dá)和共分泌的蛋白。與其他淀粉樣蛋白一樣，IAPP具有形成膜滲透性毒性低聚物的傾向。越來越多的證據(jù)表明，這些有毒的寡聚體而不是這些蛋白質(zhì)的細(xì)胞外淀粉樣蛋白形式，是導(dǎo)致神經(jīng)退行性疾病中神經(jīng)元丟失的原因。有人提出，胞內(nèi)IAPP寡聚物的形成可能會(huì)導(dǎo)致T2DM 6中的β細(xì)胞丟失。

R.Capone et al., J. Chem. Theory Comput., 8, 1143 (2012)；http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=22423218
R.Capone et al., J. Chem. Theory Comput., 8, 1143 (2012)；http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=22423218
R.Capone et al., J. Chem. Theory Comput., 8, 1143 (2012)；http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=22423218
D.H.Cribbs et al., J. Biol. Chem., 272, 7431 (1997)；http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=9054444

多肽H2N-DAsp-DAla-DGlu-DPhe-DArg-DHis-DAsp-DSer-Gly-DTyr-DGlu-DVal-DHis-DHis-DGln-DLys-DLeu-DVal-DPhe-DPhe-DAla-DGlu-DAsp-DVal-Gly-DSer-DAsn-DLys-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-COOH的合成步驟：

1、合成CTC樹脂：稱取0.8g CTC Resin（如初始取代度約為0.32mmol/g）和0.31mmol Fmoc-DAla-OH于反應(yīng)器中，加入適量DCM溶解氨基酸（需要注意，此時(shí)CTC樹脂體積會(huì)增大好幾倍，避免DCM溶液過少），再加入0.77mmol DIPEA（Mw：129.1,d：0.740g/ml），反應(yīng)2-3小時(shí)后，可不抽濾溶液，直接加入1ml的HPLC級甲醇，封端半小時(shí)。依次用DMF洗滌2次，甲醇洗滌1次，DCM洗滌一次，甲醇洗滌一次，DCM洗滌一次，DMF洗滌2次（這里使用甲醇和DCM交替洗滌，是為了更好地去除其他溶質(zhì)，有利于后續(xù)反應(yīng)）。得到  Fmoc-DAla-CTC Resin。結(jié)構(gòu)圖如下：

2、脫Fmoc：加3倍樹脂體積的20%Pip/DMF溶液，鼓氮?dú)?0分鐘，然后2倍樹脂體積的DMF 洗滌5次。得到 H2N-DAla-CTC Resin 。（此步驟脫除Fmoc基團(tuán)，茚三酮檢測為藍(lán)色，Pip為哌啶）。結(jié)構(gòu)圖如下：

3、縮合：取0.77mmol Fmoc-DIle-OH 氨基酸，加入到上述樹脂里，加適當(dāng)DMF溶解氨基酸，再依次加入1.54mmol DIPEA，0.73mmol HBTU。反應(yīng)30分鐘后，取小樣洗滌，茚三酮檢測為無色。用2倍樹脂體積的DMF 洗滌3次樹脂。（洗滌樹脂，去掉殘留溶劑，為下一步反應(yīng)做準(zhǔn)備）。得到Fmoc-DIle-DAla-CTC Resin。氨基酸：DIPEA：HBTU：樹脂=3：6：2.85：1（摩爾比）。結(jié)構(gòu)圖如下：

4、依次循環(huán)步驟二、步驟三，依次得到

H2N-DIle-DAla-CTC Resin

Fmoc-DVal-DIle-DAla-CTC Resin

H2N-DVal-DIle-DAla-CTC Resin

Fmoc-DVal-DVal-DIle-DAla-CTC Resin

H2N-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DSer(tBu)-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DSer(tBu)-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DAsp(OtBu)-DSer(tBu)-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DAsp(OtBu)-DSer(tBu)-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DHis(Trt)-DAsp(OtBu)-DSer(tBu)-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DHis(Trt)-DAsp(OtBu)-DSer(tBu)-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DArg(Pbf)-DHis(Trt)-DAsp(OtBu)-DSer(tBu)-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DArg(Pbf)-DHis(Trt)-DAsp(OtBu)-DSer(tBu)-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DPhe-DArg(Pbf)-DHis(Trt)-DAsp(OtBu)-DSer(tBu)-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DPhe-DArg(Pbf)-DHis(Trt)-DAsp(OtBu)-DSer(tBu)-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DGlu(OtBu)-DPhe-DArg(Pbf)-DHis(Trt)-DAsp(OtBu)-DSer(tBu)-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DGlu(OtBu)-DPhe-DArg(Pbf)-DHis(Trt)-DAsp(OtBu)-DSer(tBu)-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DAla-DGlu(OtBu)-DPhe-DArg(Pbf)-DHis(Trt)-DAsp(OtBu)-DSer(tBu)-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

H2N-DAla-DGlu(OtBu)-DPhe-DArg(Pbf)-DHis(Trt)-DAsp(OtBu)-DSer(tBu)-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

Fmoc-DAsp(OtBu)-DAla-DGlu(OtBu)-DPhe-DArg(Pbf)-DHis(Trt)-DAsp(OtBu)-DSer(tBu)-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin

以上中間結(jié)構(gòu)，均可在專肽生物多肽計(jì)算器-多肽結(jié)構(gòu)計(jì)算器中，一鍵畫出。

最后再經(jīng)過步驟二得到 H2N-DAsp(OtBu)-DAla-DGlu(OtBu)-DPhe-DArg(Pbf)-DHis(Trt)-DAsp(OtBu)-DSer(tBu)-Gly-DTyr(tBu)-DGlu(OtBu)-DVal-DHis(Trt)-DHis(Trt)-DGln(Trt)-DLys(Boc)-DLeu-DVal-DPhe-DPhe-DAla-DGlu(OtBu)-DAsp(OtBu)-DVal-Gly-DSer(tBu)-DAsn(Trt)-DLys(Boc)-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-CTC Resin，結(jié)構(gòu)如下：

5、切割：6倍樹脂體積的切割液（或每1g樹脂加8ml左右的切割液），搖床搖晃 2小時(shí)，過濾掉樹脂，用冰無水乙醚沉淀濾液，并用冰無水乙醚洗滌沉淀物3次，最后將沉淀物放真空干燥釜中，常溫干燥24小試，得到粗品H2N-DAsp-DAla-DGlu-DPhe-DArg-DHis-DAsp-DSer-Gly-DTyr-DGlu-DVal-DHis-DHis-DGln-DLys-DLeu-DVal-DPhe-DPhe-DAla-DGlu-DAsp-DVal-Gly-DSer-DAsn-DLys-Gly-DAla-DIle-DIle-Gly-DLeu-DMet-DVal-Gly-Gly-DVal-DVal-DIle-DAla-COOH。結(jié)構(gòu)圖見產(chǎn)品結(jié)構(gòu)圖。

切割液選擇：1）TFA：H2O=95%：5%

2）TFA：H2O：TIS=95%：2.5%：2.5%

3）三氟乙酸：茴香硫醚：1，2-乙二硫醇：苯酚：水=87.5%：5%：2.5%：2.5%：2.5%

（前兩種適合沒有容易氧化的氨基酸，例如Trp、Cys、Met。第三種適合幾乎所有的序列。）

6、純化凍干：使用液相色譜純化，收集目標(biāo)峰液體，進(jìn)行凍干，獲得蓬松的粉末狀固體多肽。不過這時(shí)要取小樣復(fù)測下純度 是否目標(biāo)純度。

7、最后總結(jié)：

杭州專肽生物技術(shù)有限公司（ALLPEPTIDE http://amynixphotography.com）主營定制多肽合成業(yè)務(wù)，提供各類長肽，短肽，環(huán)肽，提供各類修飾肽，如：熒光標(biāo)記修飾（CY3、CY5、CY5.5、CY7、FAM、FITC、Rhodamine B、TAMRA等），功能基團(tuán)修飾肽（疊氮、炔基、DBCO、DOTA、NOTA等），同位素標(biāo)記肽（N15、C13），訂書肽（Stapled Peptide）,脂肪酸修飾肽（Pal、Myr、Ste），磷酸化修飾肽（P-Ser、P-Thr、P-Tyr），環(huán)肽（酰胺鍵環(huán)肽、一對或者多對二硫鍵環(huán)），生物素標(biāo)記肽，PEG修飾肽，甲基化修飾肽等。

以上所有內(nèi)容，為專肽生物原創(chuàng)內(nèi)容，請勿發(fā)布到其他網(wǎng)站上。