ROQUEFORTINE/OXALINE BIOSYNTHESIS PATHWAY METABOLITES IN Penicillium SER. Corymbifera: IN PLANTA PRODUCTION AND IMPLICATIONS FOR COMPETITIVE FITNESS D. P. OVERY,* K. F. NIELSEN, and J. SMEDSGAARD Center for Microbial Biotechnology, Technical University of Denmark, BioCentrum-DTU, Building 221, DK-2800 Kgs. Lyngby, Denmark (Received March 5, 2005; accepted May 18, 2005) Abstract—Three strains of each of the seven taxa comprising the Penicillium series Corymbifera were surveyed by direct injection mass spectrometry (MS) and liquid chromatographyYMS for the production of terrestric acid and roquefortine/oxaline biosynthesis pathway metabolites when cultured upon macerated tissue agars prepared from Allium cepa, Zingiber officinale, and Tulipa gesneriana, and on the defined medium Czapek yeast autolysate agar (CYA). A novel solid-phase extraction methodology was applied for the rapid purification of roquefortine metabolites from a complex matrix. Penicillium hordei and P. venetum produced roquefortine D and C, whereas P. hirsutum produced roquefortine D and C and glandicolines A and B. P. albocoremium, P. allii, and P. radicicola carried the pathway through to meleagrin, producing roquefortine D and C, glandicolines A and B, and meleagrin. P. tulipae produced all previously mentioned metabolites yet carried the pathway through to an end product recognized as epi-neoxaline, prompting the proposal of a roquefortine/epi-neoxaline biogenesis pathway. Terrestric acid production was stimulated by all Corymbifera strains on plant-derived media compared to CYA controls. In planta, production of terrestric acid, roquefortine C, glandicolines A and B, meleagrin, epi-neoxaline, and several other species-related secondary metabolites were confirmed from A. cepa bulbs infected with Corymbifera strains. The deposition of roquefortine/ oxaline pathway metabolites as an extracellular nitrogen reserve for uptake and metabolism into growing mycelia and the synergistic role of terrestric 0098-0331/05/1000-2373/0 # 2005 Springer Science + Business Media, Inc. 2373 Journal of Chemical Ecology, Vol. 31, No. 10, October 2005 ( # 2005) DOI: 10.1007/s10886-005-7107-y * To whom correspondence should be addressed. E-mail: do@biocentrum.dtu.dk