Silent mutations affect in vivo protein folding in Escherichia coli.
As an approach to investigate the molecular mechanism of in vivo protein folding and the role of translation kinetics on specific folding pathways, we made codon substitutions in the EgFABP1 (Echinococcus granulosus fatty acid binding protein1) gene that replaced five minor codons with their synonymous major ones. The altered region corresponds to a turn between two short alpha helices. One of the silent mutations of EgFABP1 markedly decreased the solubility of the protein when expressed in Escherichia coli. Expression of this protein also caused strong activation of a reporter gene designed to detect misfolded proteins, suggesting that the turn region seems to have special translation kinetic requirements that ensure proper folding of the protein. Our results highlight the importance of codon usage in the in vivo protein folding.
Cortazzo
Patricia
P
Sección Bioquímica, Facultad de Ciencias, Iguá 4225, Montevideo 11400, Uruguay. cortazzo@fcien.edu.uy
Cerveñansky
Carlos
C
Marín
Mónica
M
Reiss
Claude
C
Ehrlich
Ricardo
R
Deana
Atilio
A
D019943:Amino Acid Substitution; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics; D003062:Codon; D004926:Escherichia coli / Q000235:genetics*; D050556:Fatty Acid-Binding Proteins; D029941:Fish Proteins; D008958:Models, Molecular; D009154:Mutation; D009838:Oligodeoxyribonucleotides; D010446:Peptide Fragments / Q000737:chemistry; D017510:Protein Folding; D017433:Protein Structure, Secondary
D001426:Bacterial Proteins; D002352:Carrier Proteins; D003062:Codon; C425124:FABP-1 protein, Lateolabrax japonicus; D050556:Fatty Acid-Binding Proteins; D029941:Fish Proteins; D009838:Oligodeoxyribonucleotides; D010446:Peptide Fragments