Location: National Peanut Research LaboratoryTitle: Aspergillus section Flavi, need for a robust taxonomy
|Arias De Ares, Renee
|MARTINEZ-CASTILLO, JAMES - Yucatan Center For Scientific Research
Submitted to: Microbiology Resource Announcements
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/30/2021
Publication Date: 12/2/2021
Citation: Arias De Ares, R.S., Orner, V.A., Martinez-Castillo, J., Sobolev, V. 2021. Aspergillus section Flavi, need for a robust taxonomy. Microbiology Resource Announcements. 10:48 e00784-21. https://doi.org/10.1128/MRA.00784-21.
Interpretive Summary: Postulating that two nucleotide changes can correctly identify a species in a group of organisms is not compatible with the scientific method; though is being widely used in the classification of Aspergillus section Flavi. This group, Aspergillus section Flavi, is neither physically nor reproductively isolated, and shows almost as many haplotypes as individuals. Here we describe some of the constraints of a taxonomy that uses outdated and oversimplistic tools, and we hope to make a case for a more robust system of classification that can stand the test of time.
Technical Abstract: In the era of genomics and bioinformatics when whole-genome sequencing is rapid and affordable, it is implausible that new Aspergillus species are being named based on negligible information. That is, either short DNA fragments from single genes, or different sets of genes are used to name species “new”, and also included are the chemotypes that result from a concerted expression of 25 genes in the aflatoxin-biosynthesis gene cluster (ABC), or, the use of a single randomly picked deletion out of the multiple that have been reported within the ABC. Perhaps, no new species of Aspergillus should be named unless their whole genomes have been sequenced, properly curated, and the full length of their evolutionary-conserved regions been made available (including rRNA cistron, DNA-dependent RNA Polymerase (RPB) I, II and III). In addition, it should be required a genome-wide SNP assessment to determine whether significant genetic variation would justify their placement outside a previously described species, as a basic statistics concept to establish if the variation within is larger than between groups to reject the null hypothesis. And finally, there is need for a serious consideration against the use of the ABC and/or its resulting chemotypes as part of Aspergillus taxonomy, given that multiple biological and evolutionary factors only confound classifications as it was shown for A. parvisclerotigenus syn. A. flavus.