This study investigated the combinatorial expression of xanthine dehydrogenase(XDH)and chaperone XdhC from Acinetobacter baumannii and Rhodobacter capsulatus and their applications in decreasing purine content in the ...This study investigated the combinatorial expression of xanthine dehydrogenase(XDH)and chaperone XdhC from Acinetobacter baumannii and Rhodobacter capsulatus and their applications in decreasing purine content in the beer,beef and yeast.Naturally occurring xdhABC gene clusters of A.baumannii CICC 10254 and R.capsulatus CGMCC 1.3366 as well as two refactored clusters constructed by exchanging their xdhC genes were overexpressed in Escherichia coli and purified to near homogeneity.RcXDH chaperoned by AbXdhC showed nearly the same catalytic performance as that by RcXdhC,except for the decreased substrate affinity.While the AbXDH co-expressed with RcXdhC displayed enhanced acidic adaptation but weakened catalytic activity.All the XDHs degraded purines in beer,beef and yeast extract effectively,indicating potential applications in low-purine foods to prevent hyperuricemia and gout.The study also presents a method for exploiting the better chaperone XdhC and novel XDHs by functional complement activity using existing XdhCs such as RcXdhC.展开更多
灰狼优化算法(grey wolf optimization,GWO)存在收敛的不合理性等缺陷,目前对GWO算法的收敛性改进方式较少,除此之外,当GWO迭代至后期,所有灰狼个体都逼近α狼、β狼、δ狼,导致算法陷入局部最优。针对以上问题,提出了一种增强型的灰狼...灰狼优化算法(grey wolf optimization,GWO)存在收敛的不合理性等缺陷,目前对GWO算法的收敛性改进方式较少,除此之外,当GWO迭代至后期,所有灰狼个体都逼近α狼、β狼、δ狼,导致算法陷入局部最优。针对以上问题,提出了一种增强型的灰狼优化算法(disturbance and somersault foraging-grey wolf optimization,DSF-GWO)。首先引入一种扰动因子,平衡了算法的开采和勘探能力;其次引入翻筋斗觅食策略,在后期使其不陷入局部最优的同时也使得前期的群体多样性略有提升。对DSF-GWO算法的寻优性能进行验证,选取14个单/多峰目标函数进行实验,在相同的参数设置下,结果表明DSF-GWO算法在寻优性能上较GWO算法有明显优势。展开更多
基金funded by the National Natural Science Foundation of China(21868003)the Guangxi Natural Science Foundation(2018AD19022,2017GXNSFAA198265)the Nanning Science and Technology Development Project(2017014).
文摘This study investigated the combinatorial expression of xanthine dehydrogenase(XDH)and chaperone XdhC from Acinetobacter baumannii and Rhodobacter capsulatus and their applications in decreasing purine content in the beer,beef and yeast.Naturally occurring xdhABC gene clusters of A.baumannii CICC 10254 and R.capsulatus CGMCC 1.3366 as well as two refactored clusters constructed by exchanging their xdhC genes were overexpressed in Escherichia coli and purified to near homogeneity.RcXDH chaperoned by AbXdhC showed nearly the same catalytic performance as that by RcXdhC,except for the decreased substrate affinity.While the AbXDH co-expressed with RcXdhC displayed enhanced acidic adaptation but weakened catalytic activity.All the XDHs degraded purines in beer,beef and yeast extract effectively,indicating potential applications in low-purine foods to prevent hyperuricemia and gout.The study also presents a method for exploiting the better chaperone XdhC and novel XDHs by functional complement activity using existing XdhCs such as RcXdhC.
文摘灰狼优化算法(grey wolf optimization,GWO)存在收敛的不合理性等缺陷,目前对GWO算法的收敛性改进方式较少,除此之外,当GWO迭代至后期,所有灰狼个体都逼近α狼、β狼、δ狼,导致算法陷入局部最优。针对以上问题,提出了一种增强型的灰狼优化算法(disturbance and somersault foraging-grey wolf optimization,DSF-GWO)。首先引入一种扰动因子,平衡了算法的开采和勘探能力;其次引入翻筋斗觅食策略,在后期使其不陷入局部最优的同时也使得前期的群体多样性略有提升。对DSF-GWO算法的寻优性能进行验证,选取14个单/多峰目标函数进行实验,在相同的参数设置下,结果表明DSF-GWO算法在寻优性能上较GWO算法有明显优势。
