Microsporidia: A Single Horizontal Gene Transfer Drives a Great Leap Forward

Molecular and cellular characterization of four putative nucleotide transporters from the shrimp microsporidian Enterocytozoon hepatopenaei (EHP)

Microsporidia are obligate intracellular parasites that lost several enzymes required in energy production. The expansion of transporter families in these organisms enables them to hijack ATP from hosts. In this study, nucleotide transporters of the microsporidian Enterocytozoon hepatopenaei (EHP), which causes slow growth in economically valuable Penaeus shrimp, were characterized. Analysis of the EHP genome suggested the presence of four putative nucleotide transporter genes, namely EhNTT1, EhNTT2, EhNTT3, and EhNTT4. Sequence alignment revealed four charged amino acids that are conserved in previously characterized nucleotide transporters. Phylogenetic analysis suggested that EhNTT1, 3, and 4 were derived from one horizontal gene transfer event, which was independent from that of EhNTT2. Localization of EhNTT1 and EhNTT2 using immunofluorescence analysis revealed positive signals within the envelope of developing plasmodia and on mature spores. Knockdown of EhNTT2 by double administration of sequence specific double-stranded RNA resulted in a significant reduction in EHP copy numbers, suggesting that EhNTT2 is crucial for EHP replication in shrimp. Taken together, the insight into the roles of NTTs in microsporidian proliferation can provide the biological basis for the development of alternative control strategies for microsporidian infection in shrimp.

Recent developments in horizontal gene transfer with the adaptive innovation of fermented foods

Horizontal gene transfer (HGT) has contributed significantly to the adaptability of bacteria, yeast and mold in fermented foods, whose evidence has been found in several fermented foods. Although not every HGT has biological significance, it plays an important role in improving the quality of fermented foods. In this review, how HGT facilitated microbial domestication and adaptive evolution in fermented foods was discussed. HGT can assist in the industrial innovation of fermented foods, and this adaptive evolution strategy can improve the quality of fermented foods. Additionally, the mechanism underlying HGT in fermented foods were analyzed. Furthermore, the critical bottlenecks involved in optimizing HGT during the production of fermented foods and strategies for optimizing HGT were proposed. Finally, the prospect of HGT for promoting the industrial innovation of fermented foods was highlighted. The comprehensive report on HGT in fermented foods provides a new trend for domesticating preferable starters for food fermentation, thus optimizing the quality and improving the industrial production of fermented foods.