Suc-Ala-Ala-Pro-Ile-pNA (Suc-AAPI-pNA) is a synthetic peptide compound used as a substrate for detecting and studying the activity of various proteases. Under the action of enzymes, Suc-Ala-Ala-Pro-Ile-pNA is hydrolyzed, releasing yellow p-nitroaniline (pNA). The change in absorbance at 400-410 nm is measured by colorimetry to reflect enzyme activity[1].
The structure and group characteristics of Suc-Ala-Ala-Pro-Ile-pNA are as follows:
(1)Succinyl group (Suc): Increases the water solubility and stability of the substrate.
(2)Amino acid sequence (Ala-Ala-Pro-Ile): This specific sequence mimics certain natural substrates and helps study the specificity of proteases towards different substrates.
(3)p-Nitroaniline (pNA): A common chromophoric group that releases a yellow product with absorbance characteristics upon hydrolysis, facilitating the monitoring of enzyme reactions through spectrometry.
References:
[1] Chaves-Pozo E, Valero Y, Lozano M T, et al. Fish granzyme A shows a greater role than granzyme B in fish innate cell-mediated cytotoxicity, Front. Immunol. 10 (2019) 2579[J]. 2019.
Suc-Ala-Ala-Pro-Ile-pNA（Suc-AAPI-pNA）是一种合成的肽类化合物，作为底物用于检测和研究各种蛋白酶的活性。Suc-Ala-Ala-Pro-Ile-pNA在酶的作用下水解，释放出黄色的对硝基苯胺（pNA），通过比色法测定400-410nm处吸光度的变化来反映酶活性[1]。
Suc-Ala-Ala-Pro-Ile-pNA的结构和基团特点如下：
（1）琥珀酰基团（Suc）：增加底物的水溶性和稳定性。
（2）氨基酸序列（Ala-Ala-Pro-Ile）：这一特定序列模仿了某些天然底物，有助于研究蛋白酶对不同底物的特异性。
（3）对硝基苯胺（pNA）：是一个常见的色原基团，水解后释放出具有吸光特性的黄色产物，方便通过光谱测定监测酶反应。