Structure and catalytic mechanism of N(5),N(10)-methenyl-tetrahydromethanopterin cyclohydrolase.

  title={Structure and catalytic mechanism of N(5),N(10)-methenyl-tetrahydromethanopterin cyclohydrolase.},
  author={Vikrant Upadhyay and Ulrike Demmer and Eberhard Warkentin and Johanna Moll and Seigo Shima and Ulrich Ermler},
  volume={51 42},
Methenyltetrahydromethanopterin (methenyl-H(4)MPT(+)) cyclohydrolase (Mch) catalyzes the interconversion of methenyl-H(4)MPT(+) and formyl-H(4)MPT in the one-carbon energy metabolism of methanogenic, methanotrophic, and sulfate-reducing archaea and of methylotrophic bacteria. To understand the catalytic mechanism of this reaction, we kinetically characterized site-specific variants of Mch from Archaeoglobus fulgidus (aMch) and determined the X-ray structures of the substrate-free aMch(E186Q… 

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