Diversity within Aspergillus niger Clade and Description of a New Species: Aspergillus vinaceus sp. nov.

Abstract

Diversity of species within Aspergillus niger clade, currently represented by A. niger sensu stricto and A. welwitshiae, was investigated combining three-locus gene sequences, Random Amplified Polymorphic DNA, secondary metabolites profile and morphology. Firstly, approximately 700 accessions belonging to this clade were investigated using calmodulin gene sequences. Based on these sequences, eight haplotypes were clearly identified as A. niger (n = 247) and 17 as A. welwitschiae (n = 403). However, calmodulin sequences did not provide definitive species identities for six haplotypes. To elucidate the taxonomic position of these haplotypes, two other loci, part of the beta-tubulin gene and part of the RNA polymerase II gene, were sequenced and used to perform an analysis of Genealogical Concordance Phylogenetic Species Recognition. This analysis enabled the recognition of two new phylogenetic species. One of the new phylogenetic species showed morphological and chemical distinguishable features in comparison to the known species A. welwitschiae and A. niger. This species is illustrated and described as Aspergillus vinaceus sp. nov. In contrast to A. niger and A. welwitschiae, A. vinaceus strains produced asperazine, but none of them were found to produce ochratoxin A and/or fumonisins. Sclerotium production on laboratory media, which does not occur in strains of A. niger and A. welwitschiae, and strictly sclerotium-associated secondary metabolites (14-Epi-hydroxy-10,23-dihydro-24,25-dehydroaflavinine; 10,23-Dihydro-24,25-dehydroaflavinine; 10,23-Dihydro-24,25-dehydro-21-oxo-aflavinine) were found in A. vinaceus. The strain type of A. vinaceus sp. nov. is ITAL 47,456 (T) (=IBT 35556).

Growth Enhancement of Arabidopsis (Arabidopsis thaliana) and Onion (Allium cepa) With Inoculation of Three Newly Identified Mineral-Solubilizing Fungi in the Genus Aspergillus Section Nigri

“…Our phylogenetic analyses of a combined five genes (cam, benA, rpb2, tef1, and act) revealed that three new species, A. chiangmaiensis, A. pseudopiperis, and A. pseudotubingensis, formed distinct lineages within the Aspergillus section Nigri. Morphologically, A. chiangmaiensis, A. pseudopiperis, and A. pseudotubingensis have been distinguished from the currently accepted species of Aspergillus section Nigri (Samson et al, 2014;Fungaro et al, 2017;Crous et al, 2018;da Silva et al, 2020;Doilom et al, 2020). The different morphological characteristics identified between the three new species have indicated that only A. chiangmaiensis and A. pseudopiperis could produce sclerotia (Supplementary Table 2).…”

Different repartition of the cryptic species of black aspergilli according to the anatomical sites in human infections, in a French University hospital

“…nov. recently described. 33 We mainly identified three cryptic species (A. niger, A. tubingensis, and A. welwitschiae) among the black aspergilli isolates studied. The main observation was that cryptic species were not distributed evenly between EEC and respiratory specimens.…”

Genome sequences of 24 Aspergillus niger sensu stricto strains to study strain diversity, heterokaryon compatibility, and sexual reproduction

“…The name A. niger has been used in a broad sense throughout literature to refer to species belonging to Aspergillus section Nigri , the “ A. niger aggregate,” the “black aspergilli,” “the A. niger clade,” or the “ Aspergillus niger group” ( Abarca et al 2004 ; Ferracin et al 2009 ; Nielsen et al 2009 ; da Silva et al 2020 ). However, A. niger is also referred to as a species within Aspergillus section Nigri.…”