L-Methionine sulfoximine is primarily used in research settings to study cellular processes, particularly those involving the enzyme glutamine synthetase. It acts as a potent inhibitor of this enzyme, making it valuable for investigating nitrogen metabolism in plants and animals. In plant biology, it helps elucidate the role of glutamine synthetase in nitrogen assimilation and its impact on growth and development. In neuroscience, it is utilized to explore the effects of disrupted glutamate metabolism, which can mimic certain neurological conditions, aiding in the understanding of diseases like epilepsy. Additionally, it serves as a tool in cancer research to study the dependence of tumor cells on glutamine for survival and proliferation. Its ability to induce oxidative stress also makes it useful in studies focused on cellular responses to stress and antioxidant mechanisms.