DNA barcoding in <I>Mucorales</I>: an inventory of biodiversity

Abstract

The order Mucorales comprises predominantly fast-growing saprotrophic fungi, some of which are used for the fermentation of foodstuffs but it also includes species known to cause infections in patients with severe immune or metabolic impairments. To inventory biodiversity in Mucorales ITS barcodes of 668 strains in 203 taxa were generated covering more than two thirds of the recognised species. Using the ITS sequences, Molecular Operational Taxonomic Units were defined by a similarity threshold of 99 %. An LSU sequence was generated for each unit as well. Analysis of the LSU sequences revealed that conventional phenotypic classifications of the Mucoraceae are highly artificial. The LSU- and ITS-based trees suggest that characters, such as rhizoids and sporangiola, traditionally used in mucoralean taxonomy are plesiomorphic traits. The ITS region turned out to be an appropriate barcoding marker in Mucorales. It could be sequenced directly in 82 % of the strains and its variability was sufficient to resolve most of the morphospecies. Molecular identification turned out to be problematic only for the species complexes of Mucor circinelloides, M. flavus, M. piriformis and Zygorhynchus moelleri. As many as 12 possibly undescribed species were detected. Intraspecific variability differed widely among mucorealean species ranging from 0 % in Backusella circina to 13.3 % in Cunninghamella echinulata. A high proportion of clinical strains was included for molecular identification. Clinical isolates of Cunninghamella elegans were identified molecularly for the first time. As a result of the phylogenetic analyses several taxonomic and nomenclatural changes became necessary. The genus Backusella was emended to include all species with transitorily recurved sporangiophores. Since this matched molecular data all Mucor species possessing this character were transferred to Backusella. The genus Zygorhynchus was shown to be polyphyletic based on ITS and LSU data. Consequently, Zygorhynchus was abandoned and all species were reclassified in Mucor. Our phylogenetic analyses showed, furthermore, that all non-thermophilic Rhizomucor species belong to Mucor. Accordingly, Rhizomucor endophyticus was transferred to Mucor and Rhizomucor chlamydosporus was synonymised with Mucor indicus. Lecto-, epi- or neotypes were designated for several taxa.

Differentiation of clinically relevant Mucorales Rhizopus microsporus and R. arrhizus by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS)

“…high intraspecific variability, which enhances reliable species differentiation (Walther et al, 2013). This is also expressed in the results obtained by MALDI-TOF MS and MLST analysis where overlap between species was negligible.…”

Adaptation to thermotolerance inRhizopuscoincides with virulence as revealed by avian and invertebrate infection models, phylogeny, physiological and metabolic flexibility

“…[36][37][38][39] The mesophilic group contains species able to grow around 25 C to 30 C but displaying reduced growth rates at higher temperatures. However, the ability to grow at elevated temperatures of 37 C or above, as seen for the thermotolerant Rhizopus species (Fig.…”

“…While the attenuated . 39 Bold branches show considerable bootstrap support (100 %) in the original phylogram which based on ITS sequences. The second part displays growth at different temperatures after 48 h. Maximum diameter possible for a colony is 90.00 mm, equal to the size of a petridish.…”

Identificación de hongos mucorales causantes de la pudrición blanda en frutos de papaya (Carica papaya L.) en México

“…Mucor spp. are considered a polyphyletic group, and it is therefore necessary to carry out studies in several conserved regions of the genome for its correct identification (Hyde et al, 2014;Walther et al, 2013). Gilbertella persicaria is the only species in its genus (Benny, 1991;Walther et al, 2013;Hoffmann et al, 2013) and it shows a high degree Fully Bilingual reviSta mexicana de FITOPATOLOGÍA mexican Journal oF PhytoPatholoGy respectivamente, los cuales ocasionan pudrición blanda de frutas como pera, manzana y durazno, y hortalizas como el tomate, son de rápida propagación y se han reportado ampliamente en zonas con climas tropicales y subtropicales (Michailides y Spotts, 1990).…”