BioSciences faculty publications.
For works published before Summer 2014, please see the Biochemistry & Cell Biology and Ecology & Evolutionary Biology collections.
Browse
Browsing BioSciences Publications by Author "Ajo-Franklin, Caroline M"
(eLife Sciences Publications Ltd., 2022) Tejedor-Sanz, Sara; Stevens, Eric T; Li, Siliang; Finnegan, Peter; Nelson, James; Knoesen, Andre; Light, Samuel H; Ajo-Franklin, Caroline M; Marco, Maria L
Energy conservation in microorganisms is classically categorized into respiration and fermentation; however, recent work shows some species can use mixed or alternative bioenergetic strategies. We explored the use of extracellular electron transfer for energy conservation in diverse lactic acid bacteria (LAB), microorganisms that mainly rely on fermentative metabolism and are important in food fermentations. The LAB Lactiplantibacillus plantarum uses extracellular electron transfer to increase its NAD+/NADH ratio, generate more ATP through substrate-level phosphorylation, and accumulate biomass more rapidly. This novel, hybrid metabolism is dependent on a type-II NADH dehydrogenase (Ndh2) and conditionally requires a flavin-binding extracellular lipoprotein (PplA) under laboratory conditions. It confers increased fermentation product yield, metabolic flux, and environmental acidification in laboratory media and during kale juice fermentation. The discovery of a single pathway that simultaneously blends features of fermentation and respiration in a primarily fermentative microorganism expands our knowledge of energy conservation and provides immediate biotechnology applications.