DNA-based stable-isotope probing cultivation of cryoconite samples collected from Longxiazailongba Glacier

To identify the active carbon fixation microorganisms from the complex cryoconite microbial community, the DNA-SIP methods were applied with samples collected from Longxiazailongba Glacier. We thoroughly mixed 160g of sediment sample with 320 mL sterilized ultrapure water. The 13C-labeled sodium bicarbonate (NaHCO3) was added into slurries and incubated in the light at 15 degrees celsius. Destructive sampling was performed at three-time points (20, 40, and 60 days) to obtain sufficient 13C-labeled DNA for microbial analyses.