Some other bacteria have red chlorophylls and can use light and carbon dioxide to make the sugars they need. Like all living things bacteria require mineral salts such as magnesium, calcium, iron, and others. Some bacteria are able to obtain the energy they need by oxidizing iron or sulfur. Some bacteria need sugars, vitamins, aminoacids, and other growth factors already digested and ready to use. Other bacteria can digest proteins down to amino acids and digest complex carbohydrates such as starches and table sugar down to simple sugars.
Some bacteria can make their own amino acids and vitamins from carbohydrates.
The metabolic abilities of bacteria are among the traits we use to group them into genera. Bacteria species differ greatly in the conditions they need for growth. Some grow best in cool places such as soil or bodies of water, but others are able to grow in hot springs, hot water heaters, or undersea volcanoes. The bacteria which cause disease in mammals and birds, usually grow best at body temperatures. Many bacteria which cause diseases in hydra, snakes, turtles, and other cold-blooded animals, are not able to cause disease in birds or mammals because the high body temperatures kill these bacteria or limit their growth.