Thermodynamic and kinetic analysis of the LAO binding protein and its isolated domains reveal non-additivity in stability, folding, and function
Thermodynamic and kinetic analysis of the LAO binding protein and its isolated domains reveal non-additivity in stability, folding, and function
Abstract Substrate-binding proteins (SBP) are used by organisms from the three domains of life for transport and signaling. SBPs are composed of two domains that collectively trap ligands with high affinity and selectivity. To explore the role of the domains and the integrity of the hinge region between them in the function and conformation of SBPs, here we describe the ligand binding, conformational stability, and folding kinetics of the Lysine Arginine Ornithine binding protein (LAO) from Salmonella thiphimurium and constructs corresponding to its two independent domains. LAO is a class II SBP formed by a continuous and a discontinuous domain. Contrary to the expected behavior based on their connectivity, the discontinuous domain shows a stable native-like structure that binds L-arginine with moderate affinity, whereas the continuous domain is barely stable and shows no detectable ligand binding. Regarding folding kinetics, studies of the entire protein revealed the presence of at least two intermediates. While the unfolding and refolding of the continuous domain exhibited only a single intermediate and simpler and faster kinetics than LAO, the folding mechanism of the discontinuous domain was complex and involved multiple intermediates. These findings suggest that in the complete protein the continuous domain nucleates folding and that its presence funnels the folding of the discontinuous domain avoiding nonproductive interactions. The strong dependence of the function, stability, and folding pathway of the lobes on their covalent association, is most likely the result of the coevolution of both domains as a single unit.
Berrocal Tania、Mej¨aa Eva Isela Ju¨￠rez、Romero-Romero Sergio、Vel¨￠zquez-L¨?pez Isabel、Pulido Nancy O.、Rodr¨aguez-Romero Adela、Rodr¨aguez-Sotres Rogelio、Fern¨￠ndez-Velasco D. Alejandro、Silva Daniel-Adriano、Costas Miguel、L¨?pez Sanchez Haven A.、Sosa-Peinado Alejandro、Vergara Renan
Laboratorio de Fisicoqu¨amica e Ingenier¨aa de Prote¨anas, Departamento de Bioqu¨amica, Facultad de Medicina, Universidad Nacional Aut¨?noma de M¨|xicoLaboratorio de Fisicoqu¨amica e Ingenier¨aa de Prote¨anas, Departamento de Bioqu¨amica, Facultad de Medicina, Universidad Nacional Aut¨?noma de M¨|xicoLaboratorio de Fisicoqu¨amica e Ingenier¨aa de Prote¨anas, Departamento de Bioqu¨amica, Facultad de Medicina, Universidad Nacional Aut¨?noma de M¨|xico||Department of Biochemistry, University of BayreuthLaboratorio de Fisicoqu¨amica e Ingenier¨aa de Prote¨anas, Departamento de Bioqu¨amica, Facultad de Medicina, Universidad Nacional Aut¨?noma de M¨|xicoUniversidad Aut¨?noma del Estado de MorelosInstituto de Qu¨amica, Universidad Nacional Aut¨?noma de M¨|xicoDepartamento de Bioqu¨amica Universidad Nacional Aut¨?noma de M¨|xicoLaboratorio de Fisicoqu¨amica e Ingenier¨aa de Prote¨anas, Departamento de Bioqu¨amica, Facultad de Medicina, Universidad Nacional Aut¨?noma de M¨|xicoDepartment of Biochemistry, University of Washington||Institute for Protein Design, University of WashingtonLaboratorio de Biofisicoqu¨amica, Departamento de Fisicoqu¨amica, Facultad de Qu¨amica, Universidad Nacional Aut¨?noma de M¨|xicoLaboratorio de Fisicoqu¨amica e Ingenier¨aa de Prote¨anas, Departamento de Bioqu¨amica, Facultad de Medicina, Universidad Nacional Aut¨?noma de M¨|xicoLaboratorio de Fisicoqu¨amica e Ingenier¨aa de Prote¨anas, Departamento de Bioqu¨amica, Facultad de Medicina, Universidad Nacional Aut¨?noma de M¨|xicoLaboratorio de Fisicoqu¨amica e Ingenier¨aa de Prote¨anas, Departamento de Bioqu¨amica, Facultad de Medicina, Universidad Nacional Aut¨?noma de M¨|xico
生物化学生物物理学分子生物学
Ligand-binding proteinsubstrate-binding proteinperiplasmic-binding proteinprotein domainmultidomain proteinprotein foldingprotein stabilityprotein functionkineticsthermodynamics
Berrocal Tania,Mej¨aa Eva Isela Ju¨￠rez,Romero-Romero Sergio,Vel¨￠zquez-L¨?pez Isabel,Pulido Nancy O.,Rodr¨aguez-Romero Adela,Rodr¨aguez-Sotres Rogelio,Fern¨￠ndez-Velasco D. Alejandro,Silva Daniel-Adriano,Costas Miguel,L¨?pez Sanchez Haven A.,Sosa-Peinado Alejandro,Vergara Renan.Thermodynamic and kinetic analysis of the LAO binding protein and its isolated domains reveal non-additivity in stability, folding, and function[EB/OL].(2025-03-28)[2025-05-04].https://www.biorxiv.org/content/10.1101/2023.03.18.532921.点此复制
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