The ribosome-binding site(RBS)in the 5′untranslated region is recognized by 16S rRNA to start translation and is an essential element of the gene expression system.RBSs have been widely applied in regulating gene exp...The ribosome-binding site(RBS)in the 5′untranslated region is recognized by 16S rRNA to start translation and is an essential element of the gene expression system.RBSs have been widely applied in regulating gene expression in various scenarios,including Gram-negative or Gram-positive bacteria.Here,we first rationally designed and constructed an RBS mutant library containing 66 RBSs.The strength of these RBSs in E.coli and C.glutamicum was characterized individually.The RBS strength spanned about 200 and 15 times in the two species,respectively.The strength of RBSs in C.glutamicum was generally lower than that of in E.coli.A total of 18 RBSs showed similar strength(within twofold differences)between the species in our study,and the correlation analysis of the strength of RBSs between E.coli and C.glutamicum(R^(2)=0.7483)revealed that these RBSs can be used across species.The sequence analysis revealed that the RBS region with two Ts stated was beneficial for RBS to function cross-species.The RBS characterized here can be used to precisely regulate gene expression in both hosts,and the characteristics of cross-species RBSs provide basic information for RBS rational design.展开更多
Reconfigurable battery systems(RBSs)provide a promising alternative to traditional battery systems due to their flexible and dynamically changeable topological structures that can be adapted to different battery charg...Reconfigurable battery systems(RBSs)provide a promising alternative to traditional battery systems due to their flexible and dynamically changeable topological structures that can be adapted to different battery charging and discharging strategies.A critical system parameter known as the maximum allowable current(MAC)is pivotal to RBS operation.This parameter is instrumental in maintaining the current of each individual battery within a safe range and serves as a guiding indicator for the system’s reconfiguration,ensuring its safety and reliability.This paper proposes a method for calculating the MAC of an arbitrary RBS using a greedy algorithm in conjunction with a directed graph model of the RBS.Using the shortest path of the battery,the greedy algorithm transforms the exhaustion of the switch states in the brute-force algorithm or variable search without utilizing structures in the heuristic algorithms in the combination of the shortest paths.The directed graph model,based on an equivalent circuit,provides a specific method for calculating the MAC of a given structure.The proposed method is validated using 2 previously published RBS structures and an additional one with a more complex structure.The results are the same as those from the brute-force algorithm,but the proposed method substantially improves the computational efficiency,being theoretically N_(s)2^(N_(s))−^(N_(b))log_(10)N_(b) times faster than the brute-force algorithm for an RBS with N_(b) batteries and N_(s) switches.Another advantage of the proposed method is its ability to calculate the MAC of RBSs with arbitrary structures and variable batteries,even in scenarios with random isolated batteries.展开更多
基金This work was financially supported by the National Key Research and Development Program of China(2018YFA0900300)the National Natural science foundation of China(32171421).
文摘The ribosome-binding site(RBS)in the 5′untranslated region is recognized by 16S rRNA to start translation and is an essential element of the gene expression system.RBSs have been widely applied in regulating gene expression in various scenarios,including Gram-negative or Gram-positive bacteria.Here,we first rationally designed and constructed an RBS mutant library containing 66 RBSs.The strength of these RBSs in E.coli and C.glutamicum was characterized individually.The RBS strength spanned about 200 and 15 times in the two species,respectively.The strength of RBSs in C.glutamicum was generally lower than that of in E.coli.A total of 18 RBSs showed similar strength(within twofold differences)between the species in our study,and the correlation analysis of the strength of RBSs between E.coli and C.glutamicum(R^(2)=0.7483)revealed that these RBSs can be used across species.The sequence analysis revealed that the RBS region with two Ts stated was beneficial for RBS to function cross-species.The RBS characterized here can be used to precisely regulate gene expression in both hosts,and the characteristics of cross-species RBSs provide basic information for RBS rational design.
文摘Reconfigurable battery systems(RBSs)provide a promising alternative to traditional battery systems due to their flexible and dynamically changeable topological structures that can be adapted to different battery charging and discharging strategies.A critical system parameter known as the maximum allowable current(MAC)is pivotal to RBS operation.This parameter is instrumental in maintaining the current of each individual battery within a safe range and serves as a guiding indicator for the system’s reconfiguration,ensuring its safety and reliability.This paper proposes a method for calculating the MAC of an arbitrary RBS using a greedy algorithm in conjunction with a directed graph model of the RBS.Using the shortest path of the battery,the greedy algorithm transforms the exhaustion of the switch states in the brute-force algorithm or variable search without utilizing structures in the heuristic algorithms in the combination of the shortest paths.The directed graph model,based on an equivalent circuit,provides a specific method for calculating the MAC of a given structure.The proposed method is validated using 2 previously published RBS structures and an additional one with a more complex structure.The results are the same as those from the brute-force algorithm,but the proposed method substantially improves the computational efficiency,being theoretically N_(s)2^(N_(s))−^(N_(b))log_(10)N_(b) times faster than the brute-force algorithm for an RBS with N_(b) batteries and N_(s) switches.Another advantage of the proposed method is its ability to calculate the MAC of RBSs with arbitrary structures and variable batteries,even in scenarios with random isolated batteries.
