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Phylogenetic circumscription of Arthrographis (Eremomycetaceae, Dothideomycetes).

Giraldo A, Gené J, Sutton DA, Madrid H, Cano J, Crous PW, Guarro J - Persoonia (2014)

Bottom Line: Based on these results, four new species are recognised, namely Arthrographis chlamydospora, A. curvata, A. globosa and A. longispora.Arthrographis longispora also produces membranous colonies, but has poorly differentiated conidiophores and long arthroconidia.Morphological variants are described for A. kalrae and our results also revealed that Eremomyces langeronii and A. kalrae, traditionally considered the sexual and asexual morphs of the same species, are not conspecific.

View Article: PubMed Central - PubMed

Affiliation: Unitat de Micologia, Facultat de Medicina i Ciències de la Salut and IISPV, Universitat Rovira i Virgili, Sant Llorenç 21, 43201 Reus, Tarragona, Spain;

ABSTRACT
Numerous members of Ascomycota and Basidiomycota produce only poorly differentiated arthroconidial asexual morphs in culture. These arthroconidial fungi are grouped in genera where the asexual-sexual connections and their taxonomic circumscription are poorly known. In the present study we explored the phylogenetic relationships of two of these ascomycetous genera, Arthrographis and Arthropsis. Analysis of D1/D2 sequences of all species of both genera revealed that both are polyphyletic, with species being accommodated in different orders and classes. Because genetic variability was detected among reference strains and fresh isolates resembling the genus Arthrographis, we carried out a detailed phenotypic and phylogenetic analysis based on sequence data of the ITS region, actin and chitin synthase genes. Based on these results, four new species are recognised, namely Arthrographis chlamydospora, A. curvata, A. globosa and A. longispora. Arthrographis chlamydospora is distinguished by its cerebriform colonies, branched conidiophores, cuboid arthroconidia and terminal or intercalary globose to subglobose chlamydospores. Arthrographis curvata produced both sexual and asexual morphs, and is characterised by navicular ascospores and dimorphic conidia, namely cylindrical arthroconidia and curved, cashewnut-shaped conidia formed laterally on vegetative hyphae. Arthrographis globosa produced membranous colonies, but is mainly characterised by doliiform to globose arthroconidia. Arthrographis longispora also produces membranous colonies, but has poorly differentiated conidiophores and long arthroconidia. Morphological variants are described for A. kalrae and our results also revealed that Eremomyces langeronii and A. kalrae, traditionally considered the sexual and asexual morphs of the same species, are not conspecific.

No MeSH data available.


Related in: MedlinePlus

Maximum-likelihood (ML) tree obtained from the combined DNA sequence data from three loci (ITS, ACT1, CHS1). Bootstrap support values above 70 % are indicated at the nodes. T = Ex-type strain.
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Figure 2: Maximum-likelihood (ML) tree obtained from the combined DNA sequence data from three loci (ITS, ACT1, CHS1). Bootstrap support values above 70 % are indicated at the nodes. T = Ex-type strain.

Mentions: With the primers used, we were able to amplify and sequence 300–350 bp, 450–500 bp and 750–820 bp of the CHS1 gene, the ITS region and ACT1 gene, respectively. The topology of the combined ML tree was similar to trees based on individual genes (data not shown). The combined tree included 1 544 bp and showed four main lineages (Fig. 2). The largest lineage was represented by a clade with 12 clinical strains of A. kalrae, including the ex-type strain. Sequences within the clade were practically identical, showing similarities of 98.5–100 % for each over the three loci. The second lineage (Arthrographis sp. I, 100 % bs) included one strain from marine sediments (FMR 4032) and another from nails (UTHSC 11-1163), with an intra-specific similarity of 99–100 %. The third lineage (Arthrographis sp. II) comprised only one strain (UTHSC 05-3220) from clinical origin (foot). Finally, the fourth lineage comprised a clade with three strains separated from each other by a considerable genetic distance. They were the clinical strains UTHSC 06-1053 (Arthrographis sp. III) and UTHSC 11-757 (Arthrographis sp. IV) and CBS 203.78, the ex-type strain of E. langeronii from herbivore dung. The latter two strains formed a well-supported subclade and showed genetic similarities that ranged from 93.8 % for ITS region to 96–96.7 % for CHS1 and ACT1 genes. Surprisingly, the ex-type strains of A. kalrae and E. langeronii were located in two different clades, showing genetic similarities of 94.1 % for ITS region and 92.8 % and 88.1 % for ACT1 and CHS1 genes, respectively.


Phylogenetic circumscription of Arthrographis (Eremomycetaceae, Dothideomycetes).

Giraldo A, Gené J, Sutton DA, Madrid H, Cano J, Crous PW, Guarro J - Persoonia (2014)

Maximum-likelihood (ML) tree obtained from the combined DNA sequence data from three loci (ITS, ACT1, CHS1). Bootstrap support values above 70 % are indicated at the nodes. T = Ex-type strain.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4150071&req=5

Figure 2: Maximum-likelihood (ML) tree obtained from the combined DNA sequence data from three loci (ITS, ACT1, CHS1). Bootstrap support values above 70 % are indicated at the nodes. T = Ex-type strain.
Mentions: With the primers used, we were able to amplify and sequence 300–350 bp, 450–500 bp and 750–820 bp of the CHS1 gene, the ITS region and ACT1 gene, respectively. The topology of the combined ML tree was similar to trees based on individual genes (data not shown). The combined tree included 1 544 bp and showed four main lineages (Fig. 2). The largest lineage was represented by a clade with 12 clinical strains of A. kalrae, including the ex-type strain. Sequences within the clade were practically identical, showing similarities of 98.5–100 % for each over the three loci. The second lineage (Arthrographis sp. I, 100 % bs) included one strain from marine sediments (FMR 4032) and another from nails (UTHSC 11-1163), with an intra-specific similarity of 99–100 %. The third lineage (Arthrographis sp. II) comprised only one strain (UTHSC 05-3220) from clinical origin (foot). Finally, the fourth lineage comprised a clade with three strains separated from each other by a considerable genetic distance. They were the clinical strains UTHSC 06-1053 (Arthrographis sp. III) and UTHSC 11-757 (Arthrographis sp. IV) and CBS 203.78, the ex-type strain of E. langeronii from herbivore dung. The latter two strains formed a well-supported subclade and showed genetic similarities that ranged from 93.8 % for ITS region to 96–96.7 % for CHS1 and ACT1 genes. Surprisingly, the ex-type strains of A. kalrae and E. langeronii were located in two different clades, showing genetic similarities of 94.1 % for ITS region and 92.8 % and 88.1 % for ACT1 and CHS1 genes, respectively.

Bottom Line: Based on these results, four new species are recognised, namely Arthrographis chlamydospora, A. curvata, A. globosa and A. longispora.Arthrographis longispora also produces membranous colonies, but has poorly differentiated conidiophores and long arthroconidia.Morphological variants are described for A. kalrae and our results also revealed that Eremomyces langeronii and A. kalrae, traditionally considered the sexual and asexual morphs of the same species, are not conspecific.

View Article: PubMed Central - PubMed

Affiliation: Unitat de Micologia, Facultat de Medicina i Ciències de la Salut and IISPV, Universitat Rovira i Virgili, Sant Llorenç 21, 43201 Reus, Tarragona, Spain;

ABSTRACT
Numerous members of Ascomycota and Basidiomycota produce only poorly differentiated arthroconidial asexual morphs in culture. These arthroconidial fungi are grouped in genera where the asexual-sexual connections and their taxonomic circumscription are poorly known. In the present study we explored the phylogenetic relationships of two of these ascomycetous genera, Arthrographis and Arthropsis. Analysis of D1/D2 sequences of all species of both genera revealed that both are polyphyletic, with species being accommodated in different orders and classes. Because genetic variability was detected among reference strains and fresh isolates resembling the genus Arthrographis, we carried out a detailed phenotypic and phylogenetic analysis based on sequence data of the ITS region, actin and chitin synthase genes. Based on these results, four new species are recognised, namely Arthrographis chlamydospora, A. curvata, A. globosa and A. longispora. Arthrographis chlamydospora is distinguished by its cerebriform colonies, branched conidiophores, cuboid arthroconidia and terminal or intercalary globose to subglobose chlamydospores. Arthrographis curvata produced both sexual and asexual morphs, and is characterised by navicular ascospores and dimorphic conidia, namely cylindrical arthroconidia and curved, cashewnut-shaped conidia formed laterally on vegetative hyphae. Arthrographis globosa produced membranous colonies, but is mainly characterised by doliiform to globose arthroconidia. Arthrographis longispora also produces membranous colonies, but has poorly differentiated conidiophores and long arthroconidia. Morphological variants are described for A. kalrae and our results also revealed that Eremomyces langeronii and A. kalrae, traditionally considered the sexual and asexual morphs of the same species, are not conspecific.

No MeSH data available.


Related in: MedlinePlus