天冬氨酸及赖氨酸2～10肽单链和双链的合成与毒性

目的探讨同种氨基酸形成多肽的毒性和应用前景。方法用固相合成法合成天冬氨酸和赖氨酸的2~10肽单链与双链化合物,通过小鼠尾静脉将这些化合物注射到小鼠肝脏内,观察它们对小鼠的致死作用(LD50)。结果当天冬氨酸单链2~10肽的浓度依次达到0.15、0.1、0.09、0.03、0.0065、0.03、0.034、0.035和0.04 mol/L时,小鼠的死亡率达到50%。当赖氨酸单链2~10肽的浓度依次达到0.28、0.1、0.047、0.0225、0.0028、0.00166、0.0015、0.0011和0.00075 mol/L时,小鼠的死亡率达到50%。当天冬氨酸-赖氨酸双链2~10肽的浓度依次得到0.5、0.05、0.017、0.014、0.009、0.006、0.004、0.004、0.004、0.004 mol/L时,小鼠的死亡率达到50%。结论单链多肽的毒性大于双链多肽。在2~6肽范围内,天冬氨酸单链多肽随着氨基酸数目增加毒性逐渐增加;相反,在7~10肽范围内,随着氨基酸数目的增加毒性逐渐降低。在2~10肽范围内,赖氨酸单链多肽随着氨基酸数目增加毒性逐渐增加。在2~6肽范围内,天冬氨酸-赖氨酸双链多肽随着氨基酸数目增加毒性逐渐增加;但在7~10肽范围内,其毒性相似。

Synthesis and toxicity study on the single-and double-stranded aspartic acid and lysine peptide

Objective To understand the toxicity and application prospect of polypeptide formed by the same amino acids. Methods This study focused on the solid-phase polypeptide synthesis of Asp and Lys polypeptide, and analyzed their toxicity by the method of tail vein injection to observe the lethal effect on mice. Results When the concentration of the nine kinds of single-strand asp-peptides were 0.15, 0.1, 0.09, 0.03, 0.0065, 0.03, 0.034, 0.035and 0.04 mol/L, respectively, the death rate of the BALB/c mouse was LD50. When the concentration of the nine kinds of single-strand lys-peptides were 0.28, 0.1, 0.047, 0.0225, 0.0028, 0.00166, 0.0015, 0.0011and 0.00075 mol/L, respectively, the death rate of the BALB/c mouse was LD50. When the concentration of the ten kinds of double-strand asp-lys-peptides were 0.5, 0.05, 0.017, 0.014, 0.009, 0.006, 0.004, 0.004, 0.004 and 0.004 mol /L, respectively, the death rate of the BALB/c mouse was LD50. Conclusion The toxicity of single-strand peptides was greater than that of double-strands. With the number of amino acids increasing, the toxicity of the single- strand asp-polypeptide, from dipeptide to hexapeptide, was increased, while Asp-heptapeptide to Asp-decapeptide was decreased. In the case of Lys-polypeptide, the toxicity of the single-strands was increased when the number of amino acid was increased. For the double-stranded Asp-Lys- polypeptide, by increasing the number of amino acid, the toxicity of the dipeptide to hexapeptide was increased, while heptapeptide to decapeptide had no change.