Question

which bacteria would have an optional growth temperature of 25c

Answer 1

Bacteria need certain physical and nutritional requirements for thir optimum growth. The physical requirements include temperature, oxygen, pH and osmosis while the nutritional requirements are energy source, carbon, nitrogen source, minerals, water and growth factors.

Bacteria can be classified mainly into three groups based on their optimun growth temperature. These are as follows: (a) Psychrophiles- these bacteria are cold loving as their optimum growth is between -20oC to 15oC. They are also reffered to as cryophiles and are found in the polar regions of Arctic and Antartic and deep sea. Examples are Arthrobacter, Polaromonas, Pseudomonas fragi, etc.

(b) Mesophiles- These bacteria grow at a moderate temperature, neither too hot nor too cold. Their optimum growth is between 20oC to 45oC. These are the most common type of bacteria found as such like soil bacterium, bacteria that live inside our body. Examples includes Listeria monocytogenes, Escherichia coli, Staphylococcus aureus, Streptococcus pyogenes, etc.

(c) Thermophiles- These bacteria thrives at relatively high temperature and are found in hot springs, deep sea hydrothermal vents, peat bogs and compost. Their optimum growth is between 45oC to 122oC. Examples are Thermus aquaticus, Thermococcus litoralis, etc.

The bacteria having optimal growth at 25oC temperature are Listeria monocytogenes, Escherichia coli, Staphylococcus aureus, Streptococcus pyogenes, Thiobacillus novellus, Streptococcus pneumoniae, etc