Characterization of a Revertant that Restroes the Export of Ribose-Bnding Potein to the Priplasm in Echerichia coli

리보스 결합 단백질을 페리플라슴으로 수송하는 복귀변이주의 분석

  • ;
  • ;
  • Randall, Linda L.
  • 박순희 (워싱턴 주립대학교 미생물학과) ;
  • 박찬규 (과학기술원 생물공학과) ;
  • Published : 1988.12.01

Abstract

A spontaneous revertant of mutation rbsB103 that is ribose taxis-positive was characterized. This revertant was found to be export-competent in the export of ribose-binding protein shown by the disappearance of accumulated mutant precursor protein and the export of mature ribose-binding protein to the periplasm. The reversional change was shown to be in the region of risB gene that codes for the amino terminal portion of ribose-binding protein. Analysis by high-performance liquid chromatography of peptide patterns of ribose-binding proteins confirmed the relationship between the wild-type and the revertant proteins as shown for the mutant previously (Iida et al., 1985). When the processing rate of presursor proteins from the wild type and the revertant strain in vivo was compared by pulse-chase experiment, it was found that processing is less efficient than normal in the revertant. Purified mature proteins from both wild-type and revertant were subjected to amino acid sequencing. The results confirmed the amino acid changes deduced from the DNA sequencing and showed that processing of the revertant precursor occured in the correct position even though there are two different amino acids present in the signal sequence.

Keywords

E;coli;Protein Export;Ribose-binding protein;Renertant