Physicochemical Properties
1 简介
计算蛋白序列理化性质
2 参数说明
输入蛋白序列
3 结果说明
| Field Name | Description |
|---|---|
| Sequence | 蛋白序列 |
| Molecular Weight | 蛋白序列分子量，单位为g/mol |
| Isoelectric Point | 蛋白序列等电点，返回pH值 |
| Molar Extinction Coefficient (without disulfide bond) | 假设半胱氨酸被还原时的摩尔消光系数，单位为L/(mol*cm) |
| Molar Extinction Coefficient (with disulfide bond) | 假设成对半胱氨酸形成的二硫键的摩尔消光系数，单位为L/(mol*cm) |
| Instability Index | 蛋白的不稳定指数，当该数值高于40时都表示蛋白质不稳定(半衰期很短) |
| Aromaticity | 蛋白质的芳香值，即为Phe+Trp+Tyr的相对频率 |
| Grand average of hydropathicity (GRAVY) | 总平均亲水性，若此数值为负值则说明该蛋白为亲水性蛋白，反之为疏水性蛋白 |
| Helix Fraction | 计算Helix结构在蛋白上所占比例。Helix中的氨基酸：E, M, A, L, K |
| Turn Fraction | 计算Turn结构在蛋白上所占比例。Turn中的氨基酸：N, P, G, S, D |
| Sheet Fraction | 计算Sheet结构在蛋白上所占比例。Sheet中氨基酸：V, I, Y, F, W, L, T |
| Positive Charge Percentage | 带正电荷的氨基酸的占比 |
| Negative Charge Percentage | 带负电荷的氨基酸的占比 |
| Polar Percentage | 极性氨基酸的占比 |
| Unpolar Percentage | 非极性氨基酸的占比 |
4 参考文献
[1] Bjellqvist, B.,Hughes, G.J., Pasquali, Ch., Paquet, N., Ravier, F., Sanchez, J.-Ch., Frutiger, S. & Hochstrasser, D.F. The focusing positions of polypeptides in immobilized pH gradients can be predicted from their amino acid sequences. Electrophoresis 1993, 14, 1023-1031.
https://doi.org/10.1002/elps.11501401163.
[2] Bjellqvist, B., Basse, B., Olsen, E. and Celis, J.E. Reference points for comparisons of two-dimensional maps of proteins from different human cell types defined in a pH scale where isoelectric points correlate with polypeptide compositions. Electrophoresis 1994, 15, 529-539. https://doi.org/10.1002/elps.1150150171.
[3] Guruprasad K, Reddy BV, Pandit MW. Correlation between stability of a protein and its dipeptide composition: a novel approach for predicting in vivo stability of a protein from its primary sequence. Protein Eng. 1990 Dec;4(2):155-61. PMID: 2075190. https://doi.org/10.1093/protein/4.2.155.
[4] Kyte J, Doolittle RF. A simple method for displaying the hydropathic character of a protein. J Mol Biol. 1982 May 5;157(1):105-32. PMID: 7108955. https://doi.org/10.1016/0022-2836(82)90515-0.
[5] Haimov, B., Srebnik, S. A closer look into the α-helix basin. Sci Rep 6, 38341 (2016). https://doi.org/10.1038/srep38341.
[6] Hutchinson EG, Thornton JM. A revised set of potentials for beta-turn formation in proteins. Protein Sci. 1994 Dec;3(12):2207-16. doi: 10.1002/pro.5560031206. PMID: 7756980; PMCID: PMC2142776. https://doi.org/10.1002/pro.5560031206.
[7] Kim, C., Berg, J. Thermodynamic β -sheet propensities measured using a zinc-finger host peptide. Nature 362, 267–270 (1993). https://doi.org/10.1038/362267a0.