Quantification of bacterial RubisCO genes and their expression in soil adjacent to H[subscript 2] releasing legume nodules

Abstract

The release of H[subscript 2] from legume nodules has many positive effects on soil health; H[subscript 2] has been shown to increase CO[subscript 2] fixation in soils. RubisCO plays an important role in bacterial CO[subscript 2] fixation. The effect of H[subscript 2] on CO[subscript 2] fixation was determined by quantifying the copies and expression of the RubisCO large subunit gene, cbbL. cbbL gene copies and expression were quantified from soil surrounding H[subscript 2] releasing (Hup- ) and H[subscript 2] conserving (Hup+ ) nodules and from controlled H[subscript 2] and air treated soils with varying times of exposure. A significant increase in cbbL gene copies and expression was found in H[subscript 2] treated soils compared to air treated soils. A trend was noted, that higher gene copies and expression were found in soil adjacent to Hup - nodules compared to Hup+ nodules; however, there was no significant difference between the two.