The In Vitro Translocation of Escherichia coli Ribose-binding Protein via Various Targeting Routes

  • Lee, Byoung-Chul (Department of Biological Sciences, Korea Advanced Institute of Science and Technology) ;
  • Kim, Hyoung-Nan (Department of Biological Sciences, Korea Advanced Institute of Science and Technology) ;
  • Hwang, Yong-Il (Division of Life Sciences, Kyungnam University)
  • Received : 2000.10.30
  • Accepted : 2000.12.12
  • Published : 2001.03.31

Abstract

The translocation of ribose-binding protein (RBP) into the inverted membrane vesicles (IMV) of Escherichia coli and eukaryotic microsomes was studied using the in vitro translation/translocation system. It was found that RBP was translocated into heterologous eukaryotic microsomes co-translationally, as well as post-translationally However, RBP was translocated only past-translationally into IMV. Degradation fragments of RBP with the molar mass of 14 and 16 kDa were produced during the translocation into IMV However, the amount of the degradation products decreased and the mature form of RBP appeared in the presence of phenylmethylsulfonyl fluoride (PMSF). PMSF and GTP accelerated the translocation of RBF It was also found that SecB enhanced the post-translational translocation of RBP It appears that RBP is translocated via at least two targeting paths.

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