Peptidyl-prolyl cis-trans-isomerase from Escherichia coli: a periplasmic homolog of cyclophilin that is not inhibited by cyclosporin A.
AUTOR(ES)
Liu, J
RESUMO
The prokaryotic peptidyl-prolyl cis-trans-isomerase called "rotamase", a homolog of the human cyclophilin, has been identified in Escherichia coli. The E. coli rotamase, a product of the gene we suggest be called "rot," has been purified to homogeneity after cloning of the gene by the polymerase chain reaction and its overexpression in E. coli. Based on the chymotrypsin-coupled assay using the tetrapeptide substrate succinyl-Ala-Ala-Pro-Phe-p-nitroanilide, the purified protein has rotamase activity identical to human cyclophilin with a catalytic efficiency close to the upper diffusional limit (kcat/Km approximately 1.0 x 10(7) M-1 x S-1 at 10 degrees C). Unlike the human cyclophilins, however, the E. coli rotamase is not significantly inhibited by the immunosuppressant drug cyclosporin A. By spheroplast fractionation of cells harboring the expression vector for the complete rot gene, the rotamase is located in the periplasm, where it could function in refolding of secreted proteins.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=54040Documentos Relacionados
- The gene for cyclophilin (peptidyl-prolyl cis-trans isomerase) from Schizosaccharomyces pombe.
- The Wheat Peptidyl Prolyl cis-trans-Isomerase FKBP77 Is Heat Induced and Developmentally Regulated1
- Secretion by Trypanosoma cruzi of a peptidyl-prolyl cis-trans isomerase involved in cell infection.
- A ribosome-associated peptidyl-prolyl cis/trans isomerase identified as the trigger factor.
- Regulation of the tyrosine kinase Itk by the peptidyl-prolyl isomerase cyclophilin A
