Bradyrhizobium
Bradyrhizobium species are Gram-negative, rod-shaped (also called bacilli) with a flagella (like a tail) to help them move through their environment. Gram-negative bacteria are smaller types of bacteria with thin cell walls that are sensitive to drought or water stress. They are commonly found in the soil where they can form relationships with plant roots such as peas, clover, and other legumes in a mutually beneficial, or symbiotic, relationship. In exchange for their nitrogen fixation, the Bradyrhizobium benefit from carbohydrates made by the plant. They are also common in forest soils, although these species tend not to fix nitrogen.