There are few places on Earth where bacteria of some sort has not been found to be thriving. Bacteria are identified in part by the type of environment in which they live.
Thermophiles literally means temperature-loving, and refers to bacteria that live in hot conditions. Salinophiles, which means salt-loving, can live in extremely saline or salty conditions. Acidophiles thrive under acidic conditions. Bacteria can also be identified in terms of whether they use oxygen or not. Anaerobic bacteria can live with no oxygen, whereas aerobic bacteria need oxygen to live.
Facultative anaerobes are those bacterial species which can live with oxygen, but can also thrive in oxygen free environments. Bacteria can be classified according to their shape. Bacillus bacteria are shaped like rods, coccus bacteria are shaped like spheres, and spirilus bacteria have a spiral shape. While most bacteria are harmless to humans, there are some that are extremely pathogenic. After selecting a keyword you will be taken to our online payment center where you will be required to log in before entering any payments.
Bacteria can live in hotter and colder temperatures than humans, but they do best in a warm, moist, protein-rich environment that is pH neutral or slightly acidic. There are exceptions, however. Some bacteria thrive in extreme heat or cold, while others can survive under highly acidic or extremely salty conditions. Approximately 70 percent of a bacterial cell is composed of water. Complex multi-cellular organisms, such as humans, can ingest their own water.
Single-celled bacteria lack that ability, so they must rely on finding enough available water in their environment to through their cell membranes. Many bacteria can survive for extended periods without moisture, but without it they can't grow and reproduce.
Outside of nutrients and water, each species of bacteria has a specific environmental preference. Preferences include the best pH, temperature range, amount of light, concentration of gases such as oxygen and carbon dioxide, and amount of pressure present. The pH conditions may be acidic with pH levels from 6 to 1; alkaline with pH levels from 8 to 14; or somewhat neutral with a pH of around 7.
Many bacteria grow well at or near a neutral pH of 6. Temperatures also vary, with most flourishing in the range between 40 degrees Fahrenheit and F, or 5 degrees Celsius to 60 degrees C. Microbes, even if they are supplied with all the necessary nutritional requirements, still may not grow. Bacteria, single celled eukaryotes and other microbes, can only live and reproduce within a certain range of environmental conditions.
Factors that can influence if or how microbes can grow are temperature, pH, dissolved gases, osmotic pressure and water availability. Microbes, such as bacteria are sensitive to the hydrogen ion concentration they find in their environment. Large proteins, such as enzymes, are affected by pH. Their shape changes they denature and the very often brings about an alteration of the ionic charges on the molecule.
Usually, the catalytic properties of the enzymes are lost and metabolism is halted. Upper and Lower pH Values. Most bacteria grow best around neutral pH values 6. Such acid loving microbes are called acidophiles.
Even though they can live in very acid environments, their internal pH is much closer to neutral values.
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