Jul 27, 2020 · Salt Lake filaments (Sample ID 02 in Table S1) were incubated (0.5 g wet weight) in 20 ml of 0.2 μm‐filtered lake water with the addition of 0.8 M urea in closed 50‐ml glass serum bottles with agitation (90 r.p.m., orbital shaker MaxQTM 2000, Thermo Fisher Scientific) at room temperature and under natural light cycles for 12 days. Four