Provides oxygen to the bacteroids. This role is essential for symbiotic nitrogen fixation. Monomer. Root nodules. Asp-5, Gln-6, Gly-23, Gly-24, Lys-35, Gly-42, Gln-57, Gln-65, Glu-72, Ile-75, Gln-78, Glu-127, Ile-129, and Glu-135 were also found in this pooled preparation. Belongs to the plant globin family.