A putative metal-binding site in the β subunit of rat mitochondrial processing peptidase is essential for its catalytic activity

Sakae Kitada, Kunitoshi Shimokata, Takuro Niidome, Tadashi Ogishima, Akio Ito

Research output: Contribution to journalArticle

56 Citations (Scopus)

Abstract

Mitochondrial processing peptidase (MPP) consists of α- and β-subunits (α-MPP and β-MPP). β-MPP has a putative metal-binding sequence (HXXEH). To determine whether the sequence of β-MPP is essential for the enzymatic activity, we individually mutated the histidines and glutamic acid to arginines and glutamine, respectively. The wild-type and mutated β-MPPs were co-expressed with α-MPP in Escherichia coli. All three mutants had completely lost the activity, whereas the lost activity was recovered on the addition of wild-type β-MPP. The activity of the wild-type enzyme was reduced by the mutant β-MPPs. We conclude from these observations that the HXXEH region is involved in the formation of the active site and that β-MPP is the catalytic subunit of MPP.

Original languageEnglish
Pages (from-to)1148-1150
Number of pages3
JournalJournal of biochemistry
Volume117
Issue number6
DOIs
Publication statusPublished - Jan 1 1995

All Science Journal Classification (ASJC) codes

  • Biochemistry
  • Molecular Biology

Fingerprint Dive into the research topics of 'A putative metal-binding site in the β subunit of rat mitochondrial processing peptidase is essential for its catalytic activity'. Together they form a unique fingerprint.

Cite this