Department of Biochemistry, Microbiology and Biotechnology, Yerevan State University, 1 Alex Manoogian, 0025, Yerevan, Armenia.
Sci Rep. 2024 Oct 14;14(1):23982. doi: 10.1038/s41598-024-75108-7.
This study explores the molecular mechanisms behind the differential responses of Saccharomyces cerevisiae industrial strains (ATCC 9804 and ATCC 13007) to osmotic stress. We observed that, in contrast to ATCC 9804 strain, sodium flux in ATCC 13,007 is not N, N'-dicyclohexylcarbodiimide (DCCD)-sensitive under osmotic stress, suggesting a distinct ion homeostasis mechanism. Under aerobic conditions, osmotic stress increased reduced SH groups by 45% in ATCC 9804 and 34% in ATCC 13,007. In contrast, under microaerophilic conditions, both strains experienced a 50% reduction in thiol groups. Notably, ATCC 13,007 exhibited a 1.5-fold increase in catalase (CAT) activity under aerobic stress compared to standard conditions, while ATCC 9804 showed enhanced CAT activity due to SH group binding. Additionally, superoxide dismutase (SOD) activity was doubled during aerobic growth in both strains, with ATCC 13,007 showing a 1.5-fold higher SOD activity under osmotic stress. The results demonstrate that S. cerevisiae adapts to osmotic stress differently under aerobic and microaerophilic conditions, with aerobic conditions promoting Pma-Ena-Trk interplay, reduced thiol levels and increased catalase activity, while microaerophilic conditions demonstrate Pma-Nha-Trk interplay and shifts redox balance towards oxidized thiol groups and enhance superoxide dismutase activity. Understanding these mechanisms can aid in developing stress-resistant yeast strains for industrial applications.
本研究探讨了酿酒酵母工业菌株（ATCC 9804 和 ATCC 13007）对渗透胁迫反应差异的分子机制。我们观察到，与 ATCC 9804 菌株不同，ATCC 13007 菌株在渗透胁迫下的钠离子通量对 N，N'-二环己基碳化二亚胺（DCCD）不敏感，表明存在不同的离子稳态机制。在需氧条件下，渗透胁迫使 ATCC 9804 中的还原 SH 基团增加了 45%，而在 ATCC 13007 中增加了 34%。相比之下，在微需氧条件下，两种菌株的硫醇基团都减少了 50%。值得注意的是，与标准条件相比，ATCC 13007 在需氧胁迫下的过氧化氢酶（CAT）活性增加了 1.5 倍，而 ATCC 9804 由于 SH 基团结合而增强了 CAT 活性。此外，在两种菌株的需氧生长过程中，超氧化物歧化酶（SOD）活性均增加了一倍，而在渗透胁迫下，ATCC 13007 的 SOD 活性增加了 1.5 倍。结果表明，在需氧和微需氧条件下，酿酒酵母对渗透胁迫的适应方式不同，需氧条件促进 Pma-Ena-Trk 相互作用、还原型硫醇水平降低和 CAT 活性增加，而微需氧条件则表现为 Pma-Nha-Trk 相互作用以及氧化型硫醇基团的氧化还原平衡向还原型硫醇基团转移和 SOD 活性增强。了解这些机制有助于开发用于工业应用的抗应激酵母菌株。
