Distribution of Protein-bound Hexosamine in Chloroplasts.

Intact chloroplasts of spinach (Spinacia oleracea L.), sunflower (Helianthus annuus L.), and maize (Zea mays L.) mesophyll cells contained 0.33, 0.50, and 0.14% of bound hexosamine on a protein basis, respectively. Undifferentiated maize chloroplasts contained 0.19%. Values for chloroplast lamellae were, respectively, 0.16, 0.18, 0.12, and 0.06% and for envelope membranes they were 1.6, 2.5, 3.8, and 2.7%. Thus most of the hexosamine of chloroplasts is located in the envelope membrane.