March 3, 2026

Purification and Characterization of a Novel Low-Temperature Protease BsLT with High Potential for Hydrolyzing Wheat Gluten

Key Points

The low-temperature protease BsLT shows a high specific activity of 59,675.22 U/mg at 20 °C, indicating its efficiency in low-temperature conditions.
Purification yielded a 10.08-fold increase, and the enzyme demonstrated significant hydrolysis capabilities with increased solubility and radical scavenging activities from wheat gluten.
The kinetic parameters Km and Vmax were observed at 7.14 mg/mL and 312.5 mg/(min·mL), reflecting its enzymatic efficiency.
Enhanced enzymatic activity with additives like Tween-80 and Tween-20 supports its potential application in food processing.

Abstract

Low-temperature protease has the characteristics of a high reaction rate at low temperatures. Here, a new low-temperature protease BsLT (17 kDa) was extracted from Bacillus subtilis XZ1-5 and purified with a final purification fold of 10.08 times and a specific activity of 59,675.22 U/mg. The optimum temperature and pH were 20 °C and 7, respectively. The activity of BsLT was significantly enhanced by 1% Tween-80, 1% Tween-20, and 10% DMSO. But it was less tolerant to Cu2+, Fe3+, and H2O2. The optimum substrate was casein. The Km and Vmax values were 7.14 and 312.5 mg/(min·mL), respectively. After hydrolysis by BsLT, the molecular structure of wheat gluten changed significantly. The solubility of wheat gluten increased to 150 mg/mL, OH radical scavenging ability increased to 65%, DPPH radical scavenging ability increased to 79%, and ABTS radical scavenging ability increased to 60%, which shows BsLT has the potential for further application in food processing.

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Cite This Study

Liu et al. (Thu,) studied this question.

synapsesocial.com/papers/69a75bebc6e9836116a2420c https://doi.org/https://doi.org/10.1021/acs.jafc.5c12763

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