Identifiers of EF1-α subgroups and intron configuration patterns Selleckchem Temsirolimus are indicated. Integration of intron insertion patterns and EF1-α phylogenetic distribution In order to assess the phylogenic distribution of the different
intron configuration types, they were mapped on the EF1-α tree (Figure 2). All 53 B. bassiana s.s. isolates showed an intron IC1 inserted at position 4. However, the IE intron inserted at position 1 was only present in the 10 isolates from subgroup Eu-7 and 33 out of 39 isolates from subgroup Wd-2. In particular, this subgroup included most of the Spanish isolates of B. bassiana forming an EF1-α phylogenetic group with isolates 681 from Romania and 792 from the USA [8] but displaying two different intron insertion models. Bb51 showed a unique intron insertion pattern, with an IC1 intron at position 2, and located separately in the Eu-9 subgroup. No introns were detected at any position in the three B. cf. bassiana isolates from clade C. No correlation between EF1-α phylogenetic groups and insect host was observed. Although Eu-7 subgroup did not included isolates of insect origin, the Wd-2 subgroup grouped isolates collected DAPT from Diptera, Hymenoptera, Lepidoptera and Orthoptera. Moreover, Wd-2
isolates from Orthoptera displayed different intron insertion models (i.e., Bb37, Bb39 and Bb40, and Bb42). Forty-nine Spanish and one Portuguese isolates of B. bassiana s.s. were collected from subtropical Mediterranean climate zones and were distributed
in the Eu-7, Eu-3, Wd-2 and Eu-8 subgroups. Two Spanish isolates, Bb52 and Bb53, were collected from continental climate locations and were placed within subgroups Eu-7 and Wd-2, respectively. many The only B. bassiana s.s. isolate from a humid oceanic climate included in this work, Bb51 from Santander, displayed a characteristic intron insertion model and formed the EF1-α subgroup Eu-9. In addition, Bb51 produced smaller conidia than the rest of B. bassiana isolates, this morphological feature being statistically significant (data not shown). Nevertheless, other isolate from the same climatic zone, Bb50, was grouped with other European isolates in B. cf. bassiana clade C. Discussion In the present study, we have identified different B. bassiana genotypes and phylogenetic subgroups in a collection of 57 isolates of this fungus, based on intron insertion patterns and EF1-α phylogenies, respectively. The variability in group I introns from rDNA genes has been used as a molecular tool for the identification of polymorphisms in entomopathogenic fungi [23, 30, 31]. Our study of B. bassiana LSU rDNA identified 99 introns among the 57 isolates analyzed. Four specific sites of intron insertion have been described previously in Beauveria species [23, 25], but in our collection introns were only detected at positions 1, 2 or 4. Particularly, our study shows that 100% of B. bassiana s.s. isolates had an intron inserted at position 4.