Question

Name the nitrifying bacteria of the soil. Why are they called chemoautotrophs ?

Answer 1

Nirifying bacteria:

1. These are the group of aerobic bacteria that convert ammonia into nitrates or nitrites ​in the nitrogen cycle.
2. These are generally found in the soil.
3. These are the chemolithotrophic organisms.
4. Bacteria that convert ammonia to nitrites are Nitrosomonas, Nitrosospira, Nitrosococcus, and Nitrosolobus and bacteria that convert nitrites to nitrates are Nitrobacter, Nitrospina, and Nitrococcus.

Chemoautotrophs:

1. Chemoautotrophs are the organisms that obtain their energy by the oxidation of inorganic compounds.
2. They use this energy to synthesise organic compounds from carbon dioxide.
3. Nitrifying bacteria are chemolithotrophs.
4. Chemolithotrophs are a group of phylogenetically diverse microbes that can obtain all the energy required for their growth from the oxidation of inorganic compounds such as hydrogen (H2), hydrogen sulfide (H2S), and reduced metals.
5. Since, the nitrifying bacteria use either ammonia or nitrites to obtain energy (instead of water, like plants), hence, these are called chemoautotrophs or chrmolithotrophs.