Afsari Nadhila Mutia, Listiyowati Sri, Maulana Indra, Astuti Rika Indri
Department of Biology, Faculty of Mathematics and Natural Sciences, IPB University, Bogor, Indonesia.
IPB Culture Collection, IPB University, Bogor, Indonesia.
Curr Genet. 2025 Aug 19;71(1):16. doi: 10.1007/s00294-025-01322-z.
Cadmium, a significant environmental heavy metal contaminant, poses considerable threats to human health. Cadmium detoxification by microbes, especially yeast, would serve as a potential strategy for coping with cadmium contamination. Based on the screening assay, the non-conventional yeast Wickerhamomyces anomalus BT3 exhibits cadmium stress resistance with a MIC of CdCl exceeding 1000 µM. A prolonged lag phase was observed when BT3 was exposed to > 400 µM cadmium prior to resuming growth in log phase. Thus, suggesting the presence of a cadmium-tolerant genotype in BT3 genomes. Based on the whole genome sequencing analysis, BT3 has a genome size of ~ 14Mbp with 35.0% GC content. Functional gene annotation against the EggNOG and KEGG databases revealed that most of the genes are involved in the genetic translation process. Several key genes potentially involved in cadmium tolerance were identified, including the Yeast cadmium factor (YCF1) gene, which encodes a transporter protein important for cellular homeostasis and detoxification. Genes involved in glutathione synthesis (GSH2) were detected to support the activity. In addition, genes related to oxidative stress response pathways, such as SOD1/2, TRX1, GLRX, and PRX1, were present in BT3 genomes, which promote survival under cadmium-induced oxidative stress conditions. Comparative genome analysis revealed that 2212 gene clusters (36% of BT3 gene clusters) were shared between yeasts. Interestingly, 121 gene clusters were found to be unique to BT3, which predominantly correlated with the gene ontology terms of transmembrane transport activity, integral membrane component, and dimethyl sulfide monooxygenase for the sulfur cycle. Further studies are required to clarify the potential involvement of these unique genetic properties of BT3 in coping with cadmium exposure.
镉是一种重要的环境重金属污染物，对人类健康构成重大威胁。微生物，尤其是酵母对镉的解毒作用，将成为应对镉污染的一种潜在策略。基于筛选试验，非常规酵母异常威克汉姆酵母BT3表现出对镉胁迫的抗性，其对CdCl的最低抑菌浓度超过1000µM。当BT3暴露于>400µM镉后，在进入对数生长期之前观察到延长的滞后期。因此，表明BT3基因组中存在耐镉基因型。基于全基因组测序分析，BT3的基因组大小约为14Mbp，GC含量为35.0%。针对EggNOG和KEGG数据库的功能基因注释显示，大多数基因参与遗传翻译过程。鉴定出了几个可能与耐镉性有关的关键基因，包括酵母镉因子（YCF1）基因，该基因编码一种对细胞内稳态和解毒很重要的转运蛋白。检测到参与谷胱甘肽合成的基因（GSH2）以支持该活性。此外，BT3基因组中存在与氧化应激反应途径相关的基因，如SOD1/2、TRX1、GLRX和PRX1，这些基因促进在镉诱导的氧化应激条件下的存活。比较基因组分析表明，酵母之间共有2212个基因簇（占BT3基因簇的36%）。有趣的是，发现有121个基因簇是BT3独有的，它们主要与跨膜转运活性、整合膜成分和硫循环的二甲基硫化物单加氧酶的基因本体术语相关。需要进一步研究以阐明BT3这些独特遗传特性在应对镉暴露中的潜在作用。
