Functionally accepted insertions of proteins within protein domains.
Experiments were designed to explore the tolerance of protein structure and folding to very large insertions of folded protein within a structural domain. Dihydrofolate reductase and beta-lactamase have been inserted in four different positions of phosphoglycerate kinase. The resultant chimeric proteins are all overexpressed, and the host as well as the inserted partners are functional. Although not explicitly designed, functional coupling between the two fused partners was observed in some of the chimeras. These results show that the tolerance of protein structures to very large structured insertions is more general than previously expected and supports the idea that the natural sequence continuity of a structural domain is not required for the folding process. These results directly suggest a new experimental approach to screen, for example, for folded protein in randomized polypeptide sequences.
Collinet
B
B
Laboratoire de Modélisation et d'Ingénierie des Protéines, EP1088 Université de Paris-Sud, F-91405 Orsay Cedex, France.
Herve
M
M
Pecorari
F
F
Minard
P
P
Eder
O
O
Desmadril
M
M
D000595:Amino Acid Sequence; D004926:Escherichia coli / Q000201:enzymology; D007700:Kinetics; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D010735:Phosphoglycerate Kinase / Q000737:chemistry*; D011487:Protein Conformation; D011489:Protein Denaturation; D017510:Protein Folding; D017433:Protein Structure, Secondary; D011993:Recombinant Fusion Proteins / Q000737:chemistry*; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D013762:Tetrahydrofolate Dehydrogenase / Q000737:chemistry*; D001618:beta-Lactamases / Q000737:chemistry*
D011993:Recombinant Fusion Proteins; D013762:Tetrahydrofolate Dehydrogenase; D010735:Phosphoglycerate Kinase; D001618:beta-Lactamases