?url_ver=Z39.88-2004&rft_id=10.1038%2Fnature07870&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=Gu%2C+L&rft.aulast=Gu&rft.aufirst=L&rft.issue=7247&rft.volume=459&rft.date=4+June+2009&rft.issn=0028-0836&rft.atitle=Metamorphic+enzyme+assembly+in+polyketide+diversification&rft.title=Nature&rft.pages=731+-+735&rft.genre=article