Copper complexation of methanobactin isolated from Methylosinus trichosporium OB3b: pH-dependent speciation and modeling

► Methanobactin forms 2:1-, 1:1-, and 1:2-complexes with copper. ► Cu-to-methanobactin ratios and pH determine the type of Cu-methanobactin complexes. ► Stability constants for the pH-dependent speciation are presented.