The structure of serine hydroxymethyltransferase as modeled by homology and validated by site-directed mutagenesis.
We describe a model for the three-dimensional structure of E. coli serine hydroxymethyltransferase based on its sequence homology with other PLP enzymes of the alpha-family and whose tertiary structures are known. The model suggests that certain amino acid residues at the putative active site of the enzyme can adopt specific roles in the catalytic mechanism. These proposals were supported by analysis of the properties of a number of site-directed mutants. New active site features are also proposed for further experimental testing.
Dipartimento di Scienze Biochimiche A. Rossi Fanelli and Centro di Biologia Molecolare del CNR, Università La Sapienza, Roma, Italy.
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Pascarella
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Angelaccio
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Contestabile
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S
Delle Fratte
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M
Di Salvo
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Bossa
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry; D001665:Binding Sites / Q000502:physiology; D004926:Escherichia coli / Q000201:enzymology*; D012696:Glycine Hydroxymethyltransferase / Q000737:chemistry*; D007527:Isoenzymes / Q000737:chemistry; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed / Q000235:genetics*; D009154:Mutation / Q000235:genetics; D017434:Protein Structure, Tertiary; D011732:Pyridoxal Phosphate / Q000737:chemistry; D016415:Sequence Alignment
D001426:Bacterial Proteins; D007527:Isoenzymes; D011732:Pyridoxal Phosphate; D012696:Glycine Hydroxymethyltransferase