title: Isolation, identification, and ecology of growth and taxol production by an endophytic strain of Paraconiothyrium variabile from English yew trees (Taxus baccata).
abstract: Endophytic fungi were isolated/screened from temperate Taxus baccata (Yew) for production of the anti-cancer drug taxol. Of 242 endophytic fungi isolated from surface-sterilised Yew tree twig segments, only two produced taxol in a defined liquid medium; confirmed by HPLC and LC-MS/MS analyses. They were identified by molecular means by sequencing of ITS1/ITS2 regions and shown to be Paraconiothyrium variabile and Epicoccum nigrum. They produced 1.75 and 1.32 μgL(-1) taxol respectively in a defined medium. Studies focussed on the P. variabile strain as it produced higher taxol amounts. Solute type (NaCl, KCl, Glucose, Glycerol, sorbitol), temperature (20, 25 and 30 (o)C) and water availability (water activity, aw; 0.90-0.99) on growth and taxol production by P. variabile was determined. Growth was similar on media with different solutes (1.0-1.25 mm d(-1)), optimum at 0.99 aw and 25 (o)C. In contrast, optimum taxol production was in a defined medium modified with KCl, at 0.98 aw and 20/25 (o)C, with approx. 2.3 and 7 μgL(-1) respectively. No taxol was produced at <0.96 aw, at 25-30 (o)C, and <0.94 aw at 20 (o)C. This suggests that taxol producing endophytic fungi are in English yew trees and may have potential for utilisation as cell factories for production of this pharmaceutically useful compound.
authors.affiliation: Applied Mycology Group, Cranfield Soil and AgriFood Institute, Cranfield University, Bedford MK43 0AL, UK.
authors.forename: Supunnika
authors.initials: S
authors.lastname: Somjaipeng
authors.affiliation: Applied Mycology Group, Cranfield Soil and AgriFood Institute, Cranfield University, Bedford MK43 0AL, UK.
authors.forename: Angel
authors.initials: A
authors.lastname: Medina
authors.affiliation: Department of Forest Pathology, Poznań University of Life Sciences, Poznan 60-625, Poland.
authors.forename: Hanna
authors.initials: H
authors.lastname: Kwaśna
authors.affiliation: Applied Mycology Group, Cranfield Soil and AgriFood Institute, Cranfield University, Bedford MK43 0AL, UK.
authors.forename: Jose
authors.initials: J
authors.lastname: Ordaz Ortiz
authors.affiliation: Applied Mycology Group, Cranfield Soil and AgriFood Institute, Cranfield University, Bedford MK43 0AL, UK. Electronic address: n.magan@cranfield.ac.uk.
authors.forename: Naresh
authors.initials: N
authors.lastname: Magan
mesh_terms: D000970:Antineoplastic Agents / Q000378:metabolism*; D001203:Ascomycota / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification* / Q000378:metabolism*; D002853:Chromatography, Liquid; D003470:Culture Media / Q000737:chemistry; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D060026:Endophytes / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D013058:Mass Spectrometry; D017239:Paclitaxel / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D020946:Taxus / Q000382:microbiology*
chemical_list: D000970:Antineoplastic Agents; D003470:Culture Media; D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer; D017239:Paclitaxel
keywords: Anti-cancer drug; Ecology; Taxus species