Nourseothricin sulfate is widely used as a selective agent in molecular biology and genetic engineering. It is particularly effective in selecting and maintaining genetically modified cells that carry resistance genes. In research, it is commonly applied in the cultivation of bacteria, yeast, and mammalian cells to ensure only transformed cells survive. Additionally, it serves as an antibiotic in studies involving gene expression and protein production, helping to maintain the stability of recombinant DNA constructs. Its role in cell culture systems is crucial for advancing studies in genetics, microbiology, and biotechnology.