Structure-function studies of human aromatase.

S Chen; D Zhou; K M Swiderek; N Kadohama; Y Osawa; P F Hall

doi:10.1016/0960-0760(93)90238-r

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Structure-function studies of human aromatase.

S Chen·D Zhou·K M Swiderek·N Kadohama·Y Osawa·P F Hall

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Abstract

Site-directed mutagenesis experiments have been carried out to determine the structure-function relationship of human aromatase. By sequence comparison, the region in aromatase that corresponds to the distal helix of cytochrome P-450cam has been identified to be Gln-298 to Val-313. Eight aromatase mutants with changes in this region, i.e. C299A, E302L, P308F, D309N, D309A, T310S, T310C, and S312C, have been generated using a mammalian cell stable-expression system. The results from site-directed mutagenesis studies indicate that the region containing Gln-298 to Val-313 is indeed a very important part of the active site of aromatase. The catalytic properties of P308F, D309N, and D309A have been examined in detail and are discussed. Active site-directed labeling is also an important approach to investigate the structure-function relationship of aromatase. HPLC-linked electrospray mass spectrometry is indicated as a useful technique for the characterization of active site-directed probe-modified enzyme. The mass spectral analysis of aromatase suggests that aromatase is glycosylated.

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Amino Acid Sequence Animals Aromatase Binding Sites Cell Line Humans Models, Molecular Molecular Sequence Data Mutagenesis, Site-Directed Protein Structure, Secondary Sequence Homology, Amino Acid Transfection Journal Article Research Support, U.S. Gov't, P.H.S.Review

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S Chen, D Zhou, K M Swiderek, N Kadohama, Y Osawa, P F Hall. 1993. Structure-function studies of human aromatase.. https://doi.org/10.1016/0960-0760(93)90238-r

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