Amino acid sequences of pyridoxal 5'-phosphate binding sites and fluorescence resonance energy transfer in chicken liver fatty acid synthase.
The amino acid sequences associated with pyridoxal 5'-phosphate binding sites in chicken liver fatty acid synthase have been determined: a site whose modification causes selective inhibition of the enoyl reductase activity and a site (site I) that is not associated with enzymatic activity. The amino acid sequences of peptides obtained by trypsin hydrolysis of the pyridoxamine 5'-phosphate labeled enzyme were determined. For the site associated with enoyl reductase activity, the sequence similarities between chicken and goose are extensive and include the sequence Ser-X-X-Lys, a characteristic structural feature of pyridoxamine enzymes. In addition, the spatial relationships between the pyridoxal 5'-phosphate binding sites and reductase site(s) have been studied with fluorescence resonance energy-transfer techniques. The distances between site I and the enoyl reductase and beta-ketoacyl reductase sites are greater than 50 and 41-44 A, respectively. The distance between the two reductase sites is greater than 49 A.
Chang
S I
SI
Department of Chemistry, Cornell University, Ithaca, New York 14853-1301.
Hammes
G G
GG
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002645:Chickens; D004735:Energy Transfer; D064429:Fatty Acid Synthases / Q000235:genetics / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D008433:Mathematics; D008969:Molecular Sequence Data; D011485:Protein Binding; D011732:Pyridoxal Phosphate / Q000378:metabolism*; D013050:Spectrometry, Fluorescence
D011732:Pyridoxal Phosphate; D064429:Fatty Acid Synthases