6.2 Nutritional types of microorganisms Major nutritional Sources of energy, Representative type hydrogen/electrons, microorganisms and carbon Photoautotroph Light energy,inorganic Algae,Purple and (Photolithotroph) hydrogen/electron(H/e)donor, green bacteria, CO2 carbon source Cyanobacteria Photoheterotroph Light energy,inorganic H/e Purple nonsulfur (Photoorganotroph) donor, bacteria, Organic carbon source Green sulfur bacteria Chemoautotroph Chemical energy source Sulfur-oxdizing (Chemolithotroph) (inorganic),Inorganic H/e bacteria,Hydrogen donor,CO2carbon source bacteria, Nitrifying bacteria Chemoheterotroph Chemical energy source Most bacteria,fungi, (Chenoorganotroph) (organic),Organic H/e donor, protozoa Organic carbon sourceMajor nutritional type Sources of energy, hydrogen/electrons, and carbon Representative microorganisms Photoautotroph (Photolithotroph) Light energy, inorganic hydrogen/electron(H/e- ) donor, CO2 carbon source Algae, Purple and green bacteria, Cyanobacteria Photoheterotroph (Photoorganotroph) Light energy, inorganic H/e￾donor, Organic carbon source Purple nonsulfur bacteria, Green sulfur bacteria Chemoautotroph (Chemolithotroph) Chemical energy source (inorganic), Inorganic H/e￾donor, CO2 carbon source Sulfur-oxdizing bacteria, Hydrogen bacteria, Nitrifying bacteria Chemoheterotroph (Chenoorganotroph) Chemical energy source (organic), Organic H/e- donor, Organic carbon source Most bacteria, fungi, protozoa 6.2 Nutritional types of microorganisms