CST3 and chronic kidney disease: Intriguingly, the abundances of Bacilli, Lactobacillales, Lactobacillaceae, Lactobacillus, L. johnsonii and in feces positive correlated with eGFR while negative correlated with levels of creatinine and cystatin C in the serum of CKD progression (Figs. 1d–f, 2a and supplementary Figs. 2, 3).