作者：Chase-Lubitz, Jesse
摘要：The island nation is expanding its territory by dredging up sediment from the ocean floor. But scientists, former government officials and activists say such reclamation can harm marine ecosystems and make the country more vulnerable to rising seas.
作者：Kuklewicz, Jeremi; Zimmer, Jochen
作者单位：University of Virginia; University of Virginia; Howard Hughes Medical Institute
摘要：Capsular polysaccharides (CPSs) fortify the cell boundaries of many commensal and pathogenic bacteria 1 . Through the ABC-transporter-dependent biosynthesis pathway, CPSs are synthesized intracellularly on a lipid anchor and secreted across the cell envelope by the KpsMT ABC transporter associated with the KpsE and KpsD subunits 1,2 . Here we use structural and functional studies to uncover crucial steps of CPS secretion in Gram-negative bacteria. We show that KpsMT has broad substrate specifi...
作者：Li, Siyu; Harir, Mourad; Bastviken, David; Schmitt-Kopplin, Philippe; Gonsior, Michael; Enrich-Prast, Alex; Valle, Juliana; Hertkorn, Norbert
作者单位：Helmholtz Association; Helmholtz-Center Munich - German Research Center for Environmental Health; Technical University of Munich; Linkoping University; University System of Maryland; University of Maryland Center for Environmental Science; Universidade Federal de Sao Paulo (UNIFESP)
摘要：Dissolved organic matter (DOM) is one of the most complex, dynamic and abundant sources of organic carbon, but its chemical reactivity remains uncertain 1-3 . Greater insights into DOM structural features could facilitate understanding its synthesis, turnover and processing in the global carbon cycle 4,5 . Here we use complementary multiplicity-edited 13C nuclear magnetic resonance (NMR) spectra to quantify key substructures assembling the carbon skeletons of DOM from four main Amazon rivers a...
