1 材料与方法
1.1 材料
1.2 方法
2 结果与分析
2.1 AsLEC基因T克隆菌落PCR结果
2.2 AsLEC基因编码蛋白质理化性质
表1 AsLEC蛋白质的氨基酸组成Tab. 1 Amino acid composition of AsLEC proteins |
| 氨基酸名称 Amino acid | 数量 Amount | 占比 Percentage/% | 氨基酸名称 Amino acid | 数量 Amount | 占比 Percentage/% |
|---|---|---|---|---|---|
| Ala (A) | 17 | 9.10 | Ile (I) | 12 | 6.50 |
| Arg (R) | 3 | 1.60 | Leu (L) | 17 | 9.10 |
| Asn (N) | 15 | 8.10 | Lys (K) | 6 | 3.20 |
| Asp (D) | 6 | 3.20 | Met (M) | 4 | 2.20 |
| Cys (C) | 4 | 2.20 | Phe (F) | 4 | 2.20 |
| Gln (Q) | 8 | 4.30 | Pro (P) | 9 | 4.80 |
| Glu (E) | 6 | 3.20 | Ser (S) | 13 | 7.00 |
| Gly (G) | 19 | 10.20 | Thr (T) | 16 | 8.60 |
| His (H) | 1 | 0.50 | Trp (W) | 5 | 2.70 |
| Tyr (Y) | 10 | 5.40 | Val (V) | 11 | 5.90 |
| Sec (U) | 0 | 0 | Pyl (O) | 0 | 0 |
2.3 剑麻AsLEC功能结构域分析及同源氨基酸序列比对
图4 AsLEC同源蛋白氨基酸序列比较及二级结构预测AsLEC蛋白氨基酸序列与其他物种具有较高的同源性。其中,JNetPRED(prediction)即为蛋白质二级结构预测结果,α螺旋(helices)用红色的条形表示,β折叠(sheets)用绿色箭头表示,差异主要出现在N端和C端,二级结构预测显示,AsLEC蛋白含有11个β折叠。 Fig. 4 The homology comparison of AsLEC amino acid sequence with other genes and the prediction of secondary structure for AsLEC amino acid sequence There are good homology between AsLEC protein and other species proteins. In the figure, JNetPRED represents the predicted result of secondary structure for AsLEC amino acid sequence. The differences are mainly located in the N-terminal and C-terminal. The prediction of secondary structure indicate that AsLEC protein have 11 β-pleated sheet. |
图5 lectin蛋白单体的三维结构星号$\bigstar$表示糖结合位点,不同颜色条带代表不同的亚结构模块。 Fig. 5 The Ribbon diagrams of the three-dimensional conformations for the lectin protein monomer Stars($\bigstar$)show the monosaccharide-binding sites. The ribbon of different colors represent different secondary structure motif. |
2.4 AsLEC蛋白的信号肽及跨膜结构域预测
图6 AsLEC蛋白序列信号肽预测结果横坐标为氨基酸的位置,纵坐标为每项指标对应的值。 Fig. 6 The predicted results of signal peptide for AsLEC protein The X-axis is the position of the amino acid, and the Y-axis is the value corresponding to each indicator. |
2.5 AsLEC系统进化树的构建
图8 AsLEC蛋白及其同源蛋白系统进化树分析比例尺表示氨基酸替代率。 Fig. 8 Phylogenetic tree analysis of AsLEC protein and its homologous protein system Scale represents the ratio of amino acid substitution.AsLEC: Agave sisalana lectin; GnLEC5: AAL07478.1; NtLEC: ACR15122.1; LsLEC: AAW22055.1; HvLEC: AAP57409.1; AmLEC: AAP37975.1; ZcLEC: AAM27447.1; EhLEC1: AAA19577.1; LrLEC: AAP20877.1; Ak3DAKAp: AAP04617.1; AkLECp: AAP22170.1; ZoLECp: AAV70492.1; CsLECp: AAO59506.1; ZoLEC: ACJ66865.1; EhLEC2: AAC48927.1; DpLEC: BAD67183.1; GeGas: AAX10109.1; GeAnti: AAK59994.1; ChLEC: AAA19578.1; AfLEC: BAP75575.1; AlLEC: ABF70332.1; PrLEC: AAW82332.1; DbLEC: 1LUL_F;UeLEC: 1QNW_D; SeLEC: BAD93342.1; SnLEC: AAL04121.1; HrLEC: ABW34946.1; MtLEC: KEH43013.1; RcLEC: XP_002534656.1. |
