title: Construction and characterization of chimeric proteins composed of type-1 and type-2 periplasmic binding proteins MglB and ArgT.
abstract: The respective type-1 and type-2 periplasmic binding proteins (PBPs) MglB and ArgT are believed to have evolved from a common ancestor into siblings showing topological differences in their main chain connectivity. At first glance, they show similar structure. But, more detailed examination reveals that the chain connectivity of ArgT is more convoluted than that of MglB. Reflecting that complexity, the folding of ArgT is complicated and involves intermediate folds. On the other hand, the folding of MglB is a simple two-state transition. In the present study, we constructed and characterized several chimeras made up of various subdomains of MglB and ArgT with the aim of gaining insight into the evolution of protein folding and protein structure. Although these chimeras did not fold as compactly as their parental proteins, some did exhibit cooperative folding, which suggests that novel proteins with new connectivity and new folding pathways could have emerged at a fairly high rate throughout the evolution of proteins.
authors.affiliation: Department of Protein Engineering, Cancer Institute, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Kashiwagi
authors.forename: Kaoru
authors.initials: K
authors.lastname: Fukami-Kobayashi
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Shiba
authors.forename: Ken
authors.initials: K
authors.lastname: Nishikawa
mesh_terms: D002942:Circular Dichroism; D004586:Electrophoresis; D033902:Periplasmic Binding Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D011489:Protein Denaturation; D017510:Protein Folding; D017433:Protein Structure, Secondary; D011993:Recombinant Fusion Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D012995:Solubility; D013696:Temperature
chemical_list: D033902:Periplasmic Binding Proteins; D011993:Recombinant Fusion Proteins