Regulation of thiophene biosynthesis by sulphate in roots of marigolds

Authors

  • R. R. J. ARROO,

    1. Department Of Experimental Botany, University of Nijmegen, Toernooiveld, NL-6525 ED Nijmegen, The Netherlands
    Search for more papers by this author
    • 1

      Department of Pharmaceutical Sciences, De Montfort University, The Gateway, Leicester LE1 9BH, UK.

  • J. J. M. R. JACOBS,

    1. Department Of Experimental Botany, University of Nijmegen, Toernooiveld, NL-6525 ED Nijmegen, The Netherlands
    Search for more papers by this author
    • 2

      Department of Genetics, University of Ghent, K.L. Ledeganckstraat 35, B-9000 Ghent, Belgium.

  • J. A. M. VAN GESTEL,

    1. Department Of Experimental Botany, University of Nijmegen, Toernooiveld, NL-6525 ED Nijmegen, The Netherlands
    Search for more papers by this author
  • H. KENKEL,

    1. Department Of Experimental Botany, University of Nijmegen, Toernooiveld, NL-6525 ED Nijmegen, The Netherlands
    Search for more papers by this author
  • W. JANNINK,

    1. Department Of Experimental Botany, University of Nijmegen, Toernooiveld, NL-6525 ED Nijmegen, The Netherlands
    Search for more papers by this author
  • A. F. CROES,

    Corresponding author
    1. Department Of Experimental Botany, University of Nijmegen, Toernooiveld, NL-6525 ED Nijmegen, The Netherlands
      To whom correspondence should be addressed. E-mail: croes@sci.kun.nl
    Search for more papers by this author
  • G. J. WULLEMS

    1. Department Of Experimental Botany, University of Nijmegen, Toernooiveld, NL-6525 ED Nijmegen, The Netherlands
    Search for more papers by this author

To whom correspondence should be addressed. E-mail: croes@sci.kun.nl

SUMMARY

The incorporation of [35S] sulphur in thiophenes by Tagetes patula roots was used as a model to study the regulation of secondary metabolism with a limited supply of substrate. Growth and thiophene accumulation were measured in root cultures incubated at various sulphate concentrations in the medium. A 20-fold to 40-fold reduction in the sulphate concentration did not affect elongation growth, branching and biomass production within 14 d but decreased the thiophene level to 25–50% of the control in the same period. The reduction in thiophene content was found to result from a decline in biosynthetic capacity of 80–95% after 8 d. This capacity was restored when roots were transferred to standard medium. The restoration took more than 24 h and was suppressed by cordycepin, an inhibitor of mRNA processing. It is concluded that the rate of thiophene synthesis is regulated by a control mechanism that reacts to the availability of sulphate to the roots.

Abbreviations
AcOCH2BBT

5-(but-3-en-1-ynyl)-2,2′-bithiophenyl-5′-methylacetate

BBT

5-(but-3-en-1-ynyl)-2,2′-bithienyl

BBTOAc

5-(4-acetoxy-1-butynyi)2,2′-bithienyl

BBT (OAc)2

5-(3,4,-diacetoxy-1-butynyl)2, 2′-bithienyl

BBTOH

5-(4-hydroxy-1-butynyl)2,2′-bithienyl

BPT

2-(but-3-en-1-ynyl)-5-(penta-1,3-diynyl)-thiophene

HPLC

high-perfromance liquid chromatography

MeBBT

5-(but-3-en-1-ynyl)-2,2′-bithiophenyl-5′-methane

Ancillary

Advertisement