This Article Full Text Full Text (PDF) Supplemental material Other Versions of this Article: AEM.00257-07v1 73/8/2571    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Fleetwood, D. J. Articles by Johnson, R. D. Search for Related Content PubMed PubMed Citation Articles by Fleetwood, D. J. Articles by Johnson, R. D. Agricola Articles by Fleetwood, D. J. Articles by Johnson, R. D.

A Complex Ergovaline Gene Cluster in Epichloë Endophytes of Grasses ^,

AgResearch, Grasslands Research Centre, Palmerston North, New Zealand,¹ Centre for Functional Genomics, Institute of Molecular BioSciences, Massey University, Palmerston North, New Zealand²

Received 31 January 2007/ Accepted 8 February 2007

Clavicipitaceous fungal endophytes of the genera Epichloë and Neotyphodium form symbioses with grasses of the subfamily Pooideae, in which they can synthesize an array of bioprotective alkaloids. Some strains produce the ergopeptine alkaloid ergovaline, which is implicated in livestock toxicoses caused by ingestion of endophyte-infected grasses. Cloning and analysis of a nonribosomal peptide synthetase (NRPS) gene from Neotyphodium lolii revealed a putative gene cluster for ergovaline biosynthesis containing a single-module NRPS gene, lpsB, and other genes orthologous to genes in the ergopeptine gene cluster of Claviceps purpurea and the clavine cluster of Aspergillus fumigatus. Despite conservation of gene sequence, gene order is substantially different between the N. lolii, C. purpurea, and A. fumigatus ergot alkaloid gene clusters. Southern analysis indicated that the N. lolii cluster was linked with previously identified ergovaline biosynthetic genes dmaW and lpsA. The ergovaline genes are closely associated with transposon relics, including retrotransposons and autonomous and nonautonomous DNA transposons. All genes in the cluster were highly expressed in planta, but expression was very low or undetectable in mycelia from axenic culture. This work provides a genetic foundation for elucidating biochemical steps in the ergovaline pathway, the ecological role of individual ergot alkaloid compounds, and the regulation of their synthesis in planta.

Published ahead of print on 16 February 2007.

Supplemental material for this article may be found at http://aem.asm.org/.

This article has been cited by other articles:

• van Zijll de Jong, E., Dobrowolski, M. P., Bannan, N. R., Stewart, A. V., Smith, K. F., Spangenberg, G. C., Forster, J. W. (2008). Global Genetic Diversity of the Perennial Ryegrass Fungal Endophyte Neotyphodium lolii. Crop Sci. 48: 1487-1501 [Abstract] [Full Text]  
• Markert, A., Steffan, N., Ploss, K., Hellwig, S., Steiner, U., Drewke, C., Li, S.-M., Boland, W., Leistner, E. (2008). Biosynthesis and Accumulation of Ergoline Alkaloids in a Mutualistic Association between Ipomoea asarifolia (Convolvulaceae) and a Clavicipitalean Fungus. Plant Physiol. 147: 296-305 [Abstract] [Full Text]  
• Lorenz, N., Wilson, E. V., Machado, C., Schardl, C. L., Tudzynski, P. (2007). Comparison of Ergot Alkaloid Biosynthesis Gene Clusters in Claviceps Species Indicates Loss of Late Pathway Steps in Evolution of C. fusiformis. Appl. Environ. Microbiol. 73: 7185-7191 [Abstract] [Full Text]  
• Neuhof, T., Dieckmann, R., Druzhinina, I. S., Kubicek, C. P., von Dohren, H. (2007). Intact-cell MALDI-TOF mass spectrometry analysis of peptaibol formation by the genus Trichoderma/Hypocrea: can molecular phylogeny of species predict peptaibol structures?. Microbiology 153: 3417-3437 [Abstract] [Full Text]