The essential tyrosine‐containing loop conformation and the role of the C‐terminal multi‐helix region in eukaryotic phenylalanine ammonia‐lyases

@article{Pilbk2006TheET,
  title={The essential tyrosine‐containing loop conformation and the role of the C‐terminal multi‐helix region in eukaryotic phenylalanine ammonia‐lyases},
  author={Sarolta Pilb{\'a}k and Anna Tomin and János Rétey and L{\'a}szl{\'o} Poppe},
  journal={The FEBS Journal},
  year={2006},
  volume={273}
}
Besides the post‐translationally cyclizing catalytic Ala‐Ser‐Gly triad, Tyr110 and its equivalents are of the most conserved residues in the active site of phenylalanine ammonia‐lyase (PAL, EC 4.3.1.5), histidine ammonia‐lyase (HAL, EC 4.3.1.3) and other related enzymes. The Tyr110Phe mutation results in the most pronounced inactivation of PAL indicating the importance of this residue. The recently published X‐ray structures of PAL revealed that the Tyr110‐loop was either missing (for… 
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