title: Molecular phylogeny and paclitaxel screening of fungal endophytes from Taxus globosa.
abstract: We studied the endophytic mycoflora associated with Taxus globosa, the Mexican yew. The study localities; Las Avispas (LA), San Gaspar (SG), and La Mina (LM) were three segments of cloud forest within the range of Sierra Gorda Biosphere Reserve, México. Overall, 245 endophytes were isolated and 105 representative Ascomycota (morphotaxons) were chosen for phylogenetic and genotypic characterization. Maximum likelihood analyses of large subunit of ribosomal RNA (LSU) rDNA showed well-supported clades of Dothideomycetes, Eurotiomycetes, Leotiomycetes, Pezizomycetes, and Sordariomycetes. Analyses of ITS rDNA groups showed 57 genotypes (95% sequence similarity), in general consistent with the phylogenetically delimitated taxa based on LSU rDNA sequences. The endophyte diversity measured by Fisher's α, Shanonn, and Simpson indices was ca. three-fold and ca. two-fold greater in LM than in LA and SG respectively. A screening for paclitaxel using a competitive inhibition enzyme immunoassay showed 16 positive isolates producing between 65 and 250 ng l(-1). The isolates included Acremonium, Botryosphaeria, Fusarium, Gyromitra, Nigrospora, Penicillium, three novel Pleosporales, and Xylaria.
authors.affiliation: Department of Biotechnology and Bioengineering, Cinvestav-IPN, Av. IPN 2508, Col. San Pedro Zacatenco, Mexico DF, Mexico. giovannysoca@cinvestav.mx
authors.forename: Giovanny
authors.initials: G
authors.lastname: Soca-Chafre
authors.forename: Flor N
authors.initials: FN
authors.lastname: Rivera-Orduña
authors.forename: M Eugenia
authors.initials: ME
authors.lastname: Hidalgo-Lara
authors.forename: Cesar
authors.initials: C
authors.lastname: Hernandez-Rodriguez
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Marsch
authors.forename: Luis B
authors.initials: LB
authors.lastname: Flores-Cotera
mesh_terms: D004271:DNA, Fungal / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D005658:Fungi / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D008969:Molecular Sequence Data; D017239:Paclitaxel / Q000378:metabolism*; D010802:Phylogeny; D013559:Symbiosis; D020946:Taxus / Q000382:microbiology* / Q000502:physiology
chemical_list: D004271:DNA, Fungal; D004275:DNA, Ribosomal; D017239:Paclitaxel