Binding of concanavalin A to the outer membrane of potato tuber mitochondria detected by flow cytometry

Purified and intact mitochondria isolated from potato tuber show a specific concanavalin A (Con A) binding as deduced from fluorescence labelling studies in the presence of the specific sugar α‐D‐methylmannose. This specific binding also occurs in mitoplasts, indicating the presence of Con A‐binding sites on the inner mitochondrial membrane. In contrast, the binding of wheat germ agglutinin appears non‐specific. Flow cytometry with purified mitochondria enables assessment of the binding by individual mitochondria. Thus, three mitochondrial subpopulations were identified by their reactivity towards fluorescent Con A.