Deciphering the different saccharide metabolism patterns of unconventional interspecies brewery isolates

The fermentation performance of yeasts is pivotal in very high gravity (VHG) lager beer brewing, particularly in terms of their ability to consume maltose and maltotriose. In this study, we collected two unconventional interspecies brewery isolates used in lager beer brewing, which exhibit different saccharide metabolism patterns. A hybrid of Saccharomyces cerevisiae and Saccharomyces kudriavzevii had a higher affinity for both glucose and maltotriose, while another hybrid of S. cerevisiae, Saccharomyces eubayanus, and Saccharomyces uvarum could rapidly consume more maltose. Transcriptome and comparative genomics were analyzed based on their fermentation performance during VHG brewing. We found that mutated Sk-IMAx could be helpful for maltotriose usage, while Sk-MIG2 could repress maltose consumption. Moreover, their different energy metabolism distribution also influenced the saccharide pattern greatly. The combination of heterosis from both Saccharomyces hybrids might shed light on innovation in VHG lager beer brewing and other diverse fermentation industries. Furthermore, a better understanding of cellular and genetic mechanisms could help us explore other possibilities in hybrids between Saccharomyces siblings.