Fig. 1

Differential distribution characteristics of VB12 synthesis genes in different lakes. (A) Abundance distribution patterns of identified VB12 synthesis genes in the five lakes. (B) Variations in the distribution of VB12 synthesis genes among the five lakes (Data were standardized using Z-scores, the letters (a, b, ab, bc) denote homogeneous subsets based on Duncan’s multiple range test, where groups sharing no common letters are significantly different (p < 0.05).