Pseudomonas sp. strain DJ77에 존재하는 Glutathione S-Transferase 아미노 말단잔기의 Site-directed Mutagenesis

  • Woo, Hee-Jong ;
  • Park, Yong-Chjun ;
  • Kim, Sungje ;
  • Chung, Yong-Je ;
  • Chung, An-Sik ;
  • Kim, Young-Chang
  • 우희종 (충북대학교 생명과학부) ;
  • 박용춘 (충북대학교 생명과학부) ;
  • 김성재 (충북대학교 생명과학부) ;
  • 정용제 (충북대학교 생명과학부) ;
  • 정안식 (한국과학기술원 생물과학부) ;
  • 김영창 (충북대학교 생명과학부)
  • Published : 1997.08.01

Abstract

Glutathione S-transferase (GST) was purified from Pseudomonas sp. DJ77, and its N-terminal sequence was determined to be MKLFISPGACSL. A specific tyrosyl residue in the vicinity of the N terminus is conserved in all the known cytosolic GSTs and has been shown to function as a catalytic residue in $\alpha$, $\mu$, $\pi$ class GSTs from mammals. However, Pseudomonas sp. DJ77 GST has the Phe-4 and Ile-5 instead of Tyr in N-terminus. Its replacement with tyrosine did not significantly affect the enzyme activity. Results from in vitro biochemical analyses were confirmed by the in vivo activity-based CDNB growth inhibition analyses. Our results clearly indicate that GST of Pseudomonas sp. DJ77 has a novel reaction mechanism different from that of mammalian GSTs.

Keywords

Pseudomonas sp. Strain DJ77;Glutathione Stransferase;1-chloro-2;4-dinitrobenzene(CDNB)