Bacteria constitute the foundation of all of Earth's ecosystems, being responsible for the degradation and recycling of essential elements such as car- bon, nitrogen and phosphorus. Bacteria break down dead organisms, animal waste, and plant litter to obtain nutrients. But microbes don't just eat nature's waste, they recycle it. The process of decomposition releases chemicals that can be used to build new plants and animals. A common environmental bacterium, Comamonas testosteroni, could someday become nature's plastic recycling center. While most bacteria prefer to eat sugars, C. testosteroni, instead, has a natural appetite for complex waste from plants and plastics. Biological nitrogen fixation is a process found only in some bacteria which remove N2 from the atmosphere and converts it to ammonia (NH3), for use by the plants and animals. Nitrogen fixation also results in replenishment of soil nitrogen removed by agricultural processes. Nature has its own recycling system: a group of organisms called decomposers. Decomposers feed on dead things: dead plant materials such as leaf litter and wood, animal carcasses, and feces. They perform a valuable service as Earth's cleanup crew. Microbial decomposition of natural waste also renders organic compounds and minerals bioavailable for growing crops effectively aiding in crop production. Fungi and bacteria eliminate pathogens and effectively accelerate the degradation process. Any organic waste of plant, animal or human origin needs to be decomposed to form soil organic matter. Soil microorganisms and soil invertebrates degrade or break down the complex organic form into simpler ones. Microorganisms release enzymes that oxidize the organic compounds in organic matter. The oxidation reaction releases energy and carbon, which micro-organisms need to live. The final end product of mineralization is nutrients in the mineral form. Microorganisms are responsible for the decomposing of dead organic waste of plants and animals. They can convert dead plants into simple substances. The substances generated from decomposition can be used again by other plants and animals. Microorganisms can be used to degrade harmful and smelly substances.