A protein catalytic framework with an N-terminal nucleophile is capable of self-activation

  title={A protein catalytic framework with an N-terminal nucleophile is capable of self-activation},
  author={James A. Brannigan and Guy G. Dodson and Helen J. Duggleby and Peter C. E. Moody and Janet L. Smith and Diana R. Tomchick and Alexey G. Murzin},
THE crystal structures of three amidohydrolases have been determined recently1–3: glutamine PRPP amidotransferase (GAT), penicillin acylase, and the proteasome. These enzymes use the side chain of the amino-terminal residue, incorporated in a β-sheet, as the nucleophile in the catalytic attack at the carbonyl carbon. The nucleophile is cysteine in GAT, serine in penicillin acylase, and threonine in the proteasome. Here we show that all three enzymes share an unusual fold in which the… 
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Structure of the allosteric regulatory enzyme of purine biosynthesis.
Multi-wavelength anomalous diffraction (MAD) has been used to determine the structure of the regulatory enzyme of de novo synthesis of purine nucleotides, glutamine 5-phosphoribosyl-1-pyrophosphate
Penicillin acylase has a single-amino-acid catalytic centre
The analysis shows that the environment of the catalytically active N-terminal serine of the B chain contains no adjacent histidine equivalent to that found in the serine proteases, indicating that this must be an important recognition site for cleavage.
Crystal structure of the 20S proteasome from the archaeon T. acidophilum at 3.4 A resolution.
The three-dimensional structure of the proteasome from the archaebacterium Thermoplasma acidophilum has been elucidated by x-ray crystallographic analysis by means of isomorphous replacement and
Refined structure of the pyruvoyl-dependent histidine decarboxylase from Lactobacillus 30a.
The crystal structure of the pyruvoyl-dependent histidine decarboxylase from Lactobacillus 30a has been refined to an R-value of 0.15 and a description of the overall structure is presented, focusing on secondary structure and subunit association.
Primary structure requirements for the maturation in vivo of penicillin acylase from Escherichia coli ATCC 11105.
The two constituent subunits of the enzyme penicillin acylase from Escherichia coli strain ATCC 11105 are derived from a single precursor polypeptide by post-translational processing and the processing pathway in vivo proceeds via an intermediate comprising the alpha subunits plus endopeptide and is thus identical to the pathway which has been determined previously by in vitro analysis.
Structural and evolutionary relationships in lipase mechanism and activation.
Crystal structures of a fungal lipase and a human pancreatic lipase which evidently have a divergent evolutionary history are revealed, revealing the stereochemistry at the active site and to identify the positioning of the fatty acid and the glycerol moieties.
Protein splicing: an analysis of the branched intermediate and its resolution by succinimide formation.
A succinimide at the C‐terminus of the spliced internal protein is demonstrated, implicating cyclization of asparagine in resolution of the branched intermediate, and an alkali‐labile bond is identified in the brANChed intermediate.