Sporidesmium and morphologically similar dematiaceous, hyphomycetous genera are characterised by holoblastic phragmoconidia produced on proliferating or non-proliferating conidiophores. They include ...a number of asexual (anamorphic) genera taxonomically segregated from
Sporidesmium sensu lato and are similar in having schizolytic conidial secession. The taxonomy of these ubiquitous asexual fungi and their affinities with known
Ascomycetes are, however, still obscure. This study incorporates a phylogenetic investigation, based on the LSU nu-rDNA and RNA polymerase II second largest subunit (RPB2) gene sequence, to assess the possible familial placement of
Ellisembia,
Linkosia,
Repetophragma,
Sporidesmiella,
Sporidesmium and
Stanjehughesia, and justify whether anamorphic characters are proper phylogenetic indicators. Phylogenies provide conclusive evidence to suggest that
Sporidesmium is not monophyletic and species are phylogenetically distributed in two major ascomycete classes,
Dothideomycetes and
Sordariomycetes. Morphologies currently used in their classification have undergone convergent evolution and are not phylogenetically reliable. The possible teleomorphic affinities of these anamorphic genera are discussed in light of morphology and molecular data. As these anamorphs, in most cases, are the sole known morph of the holomorph, it is proposed that in the absence of or failure to detect their teleomorphic phase, the anamorph names should be used for the holomorph.
The cloning of blunt ended DNA fragments, particularly those generated by polymerase chain reaction (PCR), is often difficult due to the inefficient ligation of blunt ends by T sub(4) DNA ligase. We ...have developed a simple procedure for the efficient cloning of blunt ended DNA fragments, even when only limited quantities are available. The method involves the ligation of the DNA fragment with an oligonucleotide linker containing a restriction enzyme site, PCR amplification of the product using the same oligonucleotide as primer, followed by restriction endonuclease digestion to generate cohesive ends and ligation into a vector with compatible ends.
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