Human chymases are important proteases abundant in mast cell granules. The elevated level of chymases and other serine proteases is closely related to inflammatory and immunoregulatory functions. Monitoring of the chymase level is very important, however, the existing methods remain limited and insufficient. In this work, a light-up probe of TPETH-2(CFTERD3) (where CFTERD is Cys-Phe-Thr-Glu-Arg-Asp) was developed for chymase detection. The probe has low fluorescent signal in aqueous media, but its solubility can be changed after hydrolysis by chymase, giving significant fluorescence turn-on with a high signal-to-noise (S/N) ratio. The probe has excellent selectivity to chymase compared to other proteins and can effectively differentiate chymase from other enzymes (e.g., chymotrypsin and trypsin) in the same family (E.C. 3.4.21). The detection limit is calculated to be 0.1 ng/mL in PBS buffer with a linear range of 0–9.0 ng/mL. A comparison study using TPETH-2(CFTERD2) as the probe reveals the importance of molecular design in realizing the high S/N ratio. TPETH-2(CFTERD3) thus represents a simple turn-on probe for chymase detection, with real-time and direct readout and also excellent sensitivity and selectivity.
人
凝乳酶是肥大细胞颗粒中含量丰富的
蛋白酶。
凝乳酶和其他
丝氨酸蛋白酶水平的升高与炎症和免疫调节功能密切相关。监测
凝乳酶水平非常重要,但现有方法仍然有限且不足。在这项工作中,我们开发了一种TPETH-2(CFTERD3)(其中CFTERD是Cys-Phe-Thr-Glu-Arg-Asp)的发光探针,用于检测
凝乳酶。该探针在
水介质中的荧光信号较低,但通过
凝乳酶水解后,其溶解度会发生变化,从而产生明显的荧光开启,且信噪比(S/N)高。与其他蛋白质相比,该探针对
凝乳酶具有极好的选择性,并且能够有效地将
凝乳酶与同一家族(E.C. 3.4.21)中的其他酶(例如胰凝乳
蛋白酶和胰
蛋白酶)区分开来。在PBS缓冲液中,检测限计算为0.1 ng/mL,线性范围为0-9.0 ng/mL。使用TPETH-2(CFTERD2)作为探针的比较研究表明,分子设计对于实现高信噪比非常重要。因此,TPETH-2(CFTERD3)是一种用于检测
凝乳酶的简单开启探针,具有实时、直接读数以及极好的灵敏度和选择性。