| Classification of Bacteria 
               1. Classification of bacteria based on Oxygen requirements (ORP)  The heterotrophic bacteria are grouped into three  classification, depending on their action toward free oxygen (O4) or  more precisely oxygen-reduction potential (ORP) for survival and optimum  growth. 
               Obligate       aerobe or Aerobes or bacteria are micro-organisms require free dissolved       oxygen to oxidize organic mate and to live and multiply. These conditions       are referred to as aerobic processes.Anaerobes       or anaerobic bacteria are micro-organisms oxidize organic matter in the       complete absence of dissolved oxygen. The micro-organisms take oxygen from       inorganic sates which contain bound oxygen (Nitrate NO3,  Sulphate So42-, Phosphate PO42-). This       mode of operation is termed as anaerobic process. Facultative       bacteria are a class of batter that use free dissolved oxygen when       available but can also Respire and  multiply in the absence. "Escherichia Coli" a facile coli from is a facultative  elaterium. 
               (Facultative  Bacteria = Aerobic anaerobic bacteria) 
                2. Classification of Microorganisms by Kingdom:  Microorganisms are organized into  five broad groups based on their structural functional differences. The groups  are called “Kingdoms”. The five kingdoms are animals, plants, protista fungi  and bacteria. Representative examples and  characteristics of differentiation are shown 
             3. Classification by their preferred Temperature Regimes:  Each specie of bacteria reproduces  best within a limited range of temperatures. Four temperature ranges for  bacteria:
 
             That       best at temperatures below 20°C are called psychrophiles.Grows       best in between 25°C  and 40°C are called Mesophiles.Between       45°C  and 60°C  thermopiles can grow.Above       60 °C stenothermophiles grow best. BACTERIA: The highest population of microorganisms  in a wastewater treatment plant will belong to the bacteria. They are  single-called organisms which use soluble food. Conditions in the treatment  plant are adjusted so that chemosererotrophs predominate. No particular species  is selected as best. 
              Metabolism: The general tern that  describes all of the chemical activities performed by a cell is metabolism.
             Divided into two parts. 
              a. Catabolism:Includes all the  biochemical processes by which a substrate is degraded to end produces with the  release of energy.  b. Anabolism:Includes all the  biochemical processes by which the bacterium synthesizes new chemical compounds needed  by the cells to hire and reproduces. |