Stressed bacteria convert significant amounts of energy-rich storage glycans into protective bacterial glycans instead of metabolizing them into carbon dioxide for energy. Our hypothesis is that bacteria are induced by stress to synthesize protective glycans that contribute to carbon sequestration. By investigating how stress induces the synthesis of protective glycans, this project directly contributes to understanding the factors that promote glycan stability and carbon sequestration in the ocean. A4 STRESS will investigate the structure of bacterial protective extracellular glycans and their potential role in carbon sequestration.