Heterologous expression of phospholipase A1 in Streptomyces mobaraensis and its application in crude oil degumming

Phospholipase A1 (PLA1) selectively hydrolyzes the sn-1 ester of phospholipids and is ideal for enzymatic oil degumming. To efficiently produce PLA1, this study heterologously expressed the saPLA1 gene from Streptomyces albidoflavus NA297 in the genome-reduced strain Streptomyces mobaraensis smYS1-Δ tg , and analyzed the enzymatic properties and degumming performance of the recombinant enzyme. Results showed that under the control of the strong promoter P gapdh and the transglutaminase (TGase) signal peptide, secretory activity peaked at 39.4 U/mL within 48 h. It exhibited optimal activity at 50°C and pH 6.0, with good stability over pH 5–8. Additionally, saPLA1 was significantly activated by Mn 2 + , Fe 2+ and citrate, and functioned in a Ca 2+ -independent manner. Under optimized process conditions, saPLA1 reduced the phosphorus content in crude soybean oil from 113.01 to 7.27 mg/kg within 2.5 h, meeting the physical refining requirement. This study provides a novel strategy for the industrial production and application of food-grade saPLA1.