Computer‐assisted in vitro reconstitution of purine degradation pathway to lower the purine content in food

Abstract

BACKGROUND With the increasing prevalence of gout and its etiological hyperuricemia, dietary control of gout based on low‐purine food according to patients' eating habits is becoming a better choice compared to the existing drug treatment such as allopurinol with notorious side effects. Reconstructing the purine metabolic pathway in vitro to degrade purine substances in food into natural functional allantoin appears to be an innovative method for preparing nutritious and healthy food of low purine content. The present study reports a computer‐assisted in vitro reconstruction of four purinolytic enzymes metabolizing adenosine into allantoin to reduce purine content in food for personalized dietary control of hyperuricemia and gout. RESULTS Under the optimum reaction conditions of 40 °C and pH 7, 0.1 U of enzymes and 0.5 mmol L−1 adenosine determined by an orthogonal test design, 16 different enzyme complexes were experimentally tested. The tested enzyme composition and allantoin production values were used as input and output to build a three‐layer back propagation artificial neural network (BP‐ANN) model, which was further optimized by a genetic algorithm (GA). The optimum enzyme complex predicted by the GA‐BP‐ANN model produced 248.08±7.832 μmol L−1 allantoin, which was 19.9% higher than equimolar mixture of enzymes, and also more efficiently lowered purine contents in beer, as well as beef and yeast extracts. CONCLUSION This is the first in vitro reconstitution of complete purine metabolic pathway by combining ANN and GA technologies, with successful application with respect to lowering the purine content in food, indicating a promising application of computer‐assisted in vitro reconstitution of purinolytic pathway in low‐purine food to prevent hyperuricemia and gout. © 2022 Society of Chemical Industry.

Removal of substrate inhibition of Acinetobacter baumannii xanthine oxidase by point mutation at Gln-201 enables efficient reduction of purine content in fish sauce

“…In addition, product inhibition of XOD also has been reported ( Radi, Tan, Prodanov, Evans, & Parks, 1992 ), but accumulation of uric acid can be eliminated by adding uric acid oxidase in industrial production. In future commercial production, the purines in fish sauce and their derived forms like xanthine or uric acid will probably be eliminated by in vitro reconstituted purinolytic enzymes, as demonstrated in our recently published paper ( Shi et al, 2022 ). Some reported that fish sauce is rich in amino acids and small peptides ( Bu et al, 2021 , Lopetcharat et al, 2001 , Wen-yu et al, 2019 ), and other active components ( Pham, Schilling, Yoon, Kamadia, & Marshall, 2008 ), which may have potential inhibitory effects on the xanthine oxidase activity ( Huang et al, 2022 , Zhao et al, 2020 ).…”

Core–shell structured microneedles with programmed drug release functions for prolonged hyperuricemia management

“…Firstly, UA can be oxidized by UOx to allantoin and H 2 O 2 . The generated allantoin is more easily absorbed and excreted by renal tubules, 37 and the injury caused by H 2 O 2 generation can be attenuated due to the high antioxidant activity of UA, 30,31,38 is further confirmed by the shifted absorption peak of UA with the increasing concentration of H 2 O 2 (Fig. S10, ESI †).…”

“…Firstly, UA can be oxidized by UOx to allantoin and H2O2. The generated allantoin is more easily absorbed and excreted by renal tubules [37] , and the injury caused by H2O2 generation can be attenuated due to the high antioxidant activity of UA [30,31,38] , which is further confirmed by the shifted absorption peak of UA with the increasing concentration of H2O2 (Figure S10). Afterwards, CaO2 NP is exposed as a high-quality oxygen release reagent, and the generated O2 provides an essential support for the catalytic oxidation of uric acid by UOx.…”