16 Sep

Anaerobes

Bacteria can be classified into two groups based on their oxygen needs.  Obligate aerobes and anaerobes.  Aerobes require oxygen for growth because they perform respiratory metabolism which utilizes oxygen as a final electron acceptor.  Anaerobes can be further divided into sub groups depending on their sensitivity to oxygen.  Aerotolerant anaerobes can grow in the presence of oxygen and are not usually harmed by its presence.  Their metabolism does not require oxygen but does however involve fermentation which uses different compounds as a final electron acceptor.  Obligate anaerobes can’t tolerate oxygen and must be cultivated under conditions in which oxygen is removed ortherwise they are killed.  Obligate anaerobes use fermentation and anaerobic respiration for energy production.  Inorganic compounds such as nitrates or sulfate replace oxygen as the final electron acceptor.  It is believed that most strict anaerobes contain enzymes and proteins that can be easily damaged by the presence of oxygen.  One can culture anaerobic bacteria by utilizing the unique funcionality of the Gaspak anaerobic jar system.