Sexual Reproduction in Aspergillus Tubingensis From Section Nigri

Mycologia. Sep-Oct 2013;105(5):1153-63. doi: 10.3852/13-101. Epub 2013 May 24.

Abstract

A sclerotium-forming member of Aspergillus section Nigri was sampled from a population in a single field in North Carolina, USA, and identified as A. tubingensis based on genealogical concordance analysis. Aspergillus tubingensis was shown to be heterothallic, with individual strains containing either a MAT1-1 or MAT1-2 mating-type gene. Strains of opposite mating type were crossed on mixed cereal agar and incubated for 5-6 months. Stromata typically formed 1-2 indehiscent ascocarps containing asci and ascospores within the pseudo-parenchymatous matrix in a manner similar to the Petromyces sexual stage from section Flavi, which is closely related to section Nigri. Ascospores of A. tubingensis differed from those of section Flavi species in the reticulate ornamentation of ascospores and the presence of two crests that form an equatorial furrow. Sexual reproduction in A. tubingensis may be useful for enhancing enzyme and organic acid production through recombination-mediated genetic engineering of industrial strains.

Keywords: A. niger; Aspergillus flavus; ascospores; heterothallism; mating type; sclerotium; stroma.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Aspergillus / classification
  • Aspergillus / cytology
  • Aspergillus / genetics
  • Aspergillus / physiology*
  • Base Sequence
  • DNA, Fungal / chemistry
  • DNA, Fungal / genetics
  • Genes, Mating Type, Fungal / genetics*
  • Molecular Sequence Data
  • North Carolina
  • Phylogeny
  • Reproduction
  • Sequence Analysis, DNA
  • Soil Microbiology*
  • Spores, Fungal

Substances

  • DNA, Fungal

Associated data

  • GENBANK/KC848771
  • GENBANK/KC848772
  • GENBANK/KC848773
  • GENBANK/KC848774
  • GENBANK/KC848775
  • GENBANK/KC848776
  • GENBANK/KC848777