AUTHOR=Peng Mao , Aguilar-Pontes Maria V. , de Vries Ronald P. , Mäkelä Miia R. 

TITLE=In Silico Analysis of Putative Sugar Transporter Genes in Aspergillus niger Using Phylogeny and Comparative Transcriptomics

JOURNAL=Frontiers in Microbiology

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2018.01045

DOI=10.3389/fmicb.2018.01045

ISSN=1664-302X

ABSTRACT=<p><italic>Aspergillus niger</italic> is one of the most widely used fungi to study the conversion of the lignocellulosic feedstocks into fermentable sugars. Understanding the sugar uptake system of <italic>A. niger</italic> is essential to improve the efficiency of the process of fungal plant biomass degradation. In this study, we report a comprehensive characterization of the sugar transportome of <italic>A. niger</italic> by combining phylogenetic and comparative transcriptomic analyses. We identified 86 putative sugar transporter (ST) genes based on a conserved protein domain search. All these candidates were then classified into nine subfamilies and their functional motifs and possible sugar-specificity were annotated according to phylogenetic analysis and literature mining. Furthermore, we comparatively analyzed the ST gene expression on a large set of fungal growth conditions including mono-, di- and polysaccharides, and mutants of transcriptional regulators. This revealed that transporter genes from the same phylogenetic clade displayed very diverse expression patterns and were regulated by different transcriptional factors. The genome-wide study of STs of <italic>A. niger</italic> provides new insights into the mechanisms underlying an extremely flexible metabolism and high nutritional versatility of <italic>A. niger</italic> and will facilitate further biochemical characterization and industrial applications of these candidate STs.</p>