Bacteria and viruses such as E-coli and salmonella can live in freezing temperatures, meaning they are alive in your ice cubes. The good news is by using purified water, cleaning your hands, or using ice scoops when serving, and regularly cleaning your freezer, you can stop the bacteria from spreading. The microorganisms live in every part of the biosphere, and some of them are even capable of growing at low temperatures, including those below the freezing point. To protect themselves from these effects, many microbes produce antifreeze proteins. These molecules bind to microscopic ice crystals, preventing them from clustering together to form larger crystals. In this way they lower the water's freezing point, causing it to remain liquid even at -18°C. Aerobic bacteria thrive in the presence of oxygen and require it for their continued growth and existence. Other bacteria are anaerobic, and cannot tolerate gaseous oxygen, such as those bacteria which live in deep underwater sediments or those which cause bacterial food poisoning. At pH 12.0 for 72 h or less, which were the harshest parameters tested, sodium hydroxide was 100% bactericidal to all of the bacteria tested. However, a lower sodium hydroxide concentration was bactericidal to many bacteria. Bacteria grow most rapidly in the range of temperatures between 40 °F and 140 °F, doubling in number in as little as 20 minutes. This range of temperatures is often called the "Danger Zone." Never leave food out of refrigeration over 2 hours. Alternately, when temperatures reach below 18°C/64°F, microorganism growth decreases and nearly ceases when temperatures reach the freezing point of water. Studies have indicated that the growth of microorganisms, such as fungus and bacteria, completely cease when temperatures reach < -18°C/0°F.

Aerobic bacteria live in normal air containing 21% oxygen. However, when aerobic bacteria is engulfed in clusters of oxygen composed of 100% pure oxygen and is continually bombarded with electron shots, it quickly dies. Whereas essentially all eukaryotic organisms require oxygen to thrive, many species of bacteria can grow under anaerobic conditions. Bacteria that require oxygen to grow are called obligate aerobic bacteria. Anaerobic bacteria are germs that can survive and grow where there is no oxygen. As it can thrive in human tissue that is injured and does not have oxygen-rich blood flowing to it. Infections like tetanus and gangrene are caused by anaerobic bacteria. 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. All animals, including you, need oxygen to breathe. Many kinds of tiny microorganisms also need oxygen. But some microbes have a superpower: they can breathe a different element as nitrogen. This means they can live in areas where there is no oxygen. Like all other organisms, bacteria need water to survive, but the surfaces of leaves experience daily changes in moisture, tending to be much wetter at night than during the day.The microorganisms live in every part of the biosphere, and some of them are even capable of growing at low temperatures, including those below the freezing point. Bacteria and viruses such as E-coli and salmonella can live in freezing temperatures, meaning they are alive in your ice cubes. The good news is by using purified water, cleaning your hands, or using ice scoops when serving, and regularly cleaning your freezer, you can stop the bacteria from spreading.The majority of the microbial community is of psychrotolerant types able to grow at 0°C but with optimum temperatures >20°C; while even the small proportion of obligate psychrophiles have optimum temperatures greater than the environmental temperature. Freezing does not kill germs and bacteria. Instead, it essentially puts them into hibernation. They are inactive while the food is frozen and will “wake up” as soon as the food thaws and as the food thaws, so will the moisture, which means the bacteria will have the moisture it needs to survive.

The answer depends on the type of bacteria. Yes, there are types that can survive in freezing because they have cold shock proteins. And with regard to their need for air, it also depends on the type of bacteria, as bacteria can be divided, depending on their need for oxygen, into three groups, which are aerobic bacteria, which need oxygen, and facultative anaerobes, which can live with or without the presence of oxygen, and anaerobic bacteria to which oxygen is toxic, and of course this depends on the type of respiratory enzymes they have.

Thanks Dr Manal Hadi Kanaan for participating in the discussion.

The microorganisms live in every part of the biosphere, and some of them are even capable of growing at low temperatures, including those below the freezing point. Bacteria require a minimum level of oxygen for growth, about 1%–10%, well below the 21% found in the atmosphere. Examples of obligate aerobes are Mycobacterium tuberculosis, the causative agent of tuberculosis and Micrococcus luteus, a gram-positive bacterium that colonizes the skin. Bacteria and many microorganisms are very sensitive to oxygen concentrations. Some will only grow in its presence and are called obligate aerobes. Facultative aerobes will grow either aerobically or in the absence of oxygen (anaerobic conditions), but they generally do better with oxygen. Like all other organisms, bacteria need water to survive, but the surfaces of leaves experience daily changes in moisture, tending to be much wetter at night than during the day. Whereas essentially all eukaryotic organisms require oxygen to thrive, many species of bacteria can grow under anaerobic conditions. Bacteria that require oxygen to grow are called obligate aerobic bacteria. Bacteria perform two types of cellular respiration, aerobic and anaerobic. In aerobic cellular respiration there are three main steps, glycolysis and the citric acid cycle, which occur in the cytoplasm and the electron transport chain, which occurs in the plasma membrane. Unlike soil microbes, which can be regarded as native to their environment, microbes found in the air only get there by being introduced from another source. Indeed, certain human activities, such as waste disposal, waste treatment, agriculture and industry, have the potential to release microbes into the air.