Bacterial Physiology
Bacterial Physiology
Bacterial chemical components o Water: free water and compound water o Inorganic salt: phosphus, potassium magnesium calcium. nitrium etc Protein 50%0-80% of dry weight according bacterial kinds and age o Sugar: mainly distributing in cell wall and capsule Lipids: composed of lipid, fatty acid, wax, etc Nucleic acid: rna and dNA
Bacterial chemical components ⚫ Water: free water and compound water. ⚫ Inorganic salt: phosphus, potassium magnesium, calcium, nitrium,etc. ⚫ Protein: 50%-80% of dry weight according bacterial kinds and age. ⚫ Sugar: mainly distributing in cell wall and capsule. ⚫ Lipids: composed of lipid, fatty acid, wax, etc. ⚫ Nucleic acid: RNA and DNA
Approximate Composition of a Microbial Cell ( Dry Weight) Sodium 1% Calcium 0.5%, Magnesium 0.5%, Chlorine 0. 5% Potassium 1% Iron 0.2% All others.3%6 Sulfur 1 1% Phosphorus 3% Hydrogen 8% Nitrogen 14% Carbon 50% xygen 20%
Major elements, their sources and functions in bacterial cells bo of dry ment Function Carbon organic compounds Main constituent of cellular material H2O organIc Constituent of cell material and cell water: O2 Oxvgen compounds, CO2 and is electron acceptor in aerobic respiration Nitrogen NH3. NO3. organic Constituent of amino acids, nucleic acids compounds, N2 nucleotides and coenzymes H2O. organic Main constituent of organic compounds and Hvdrogen compounds, H2 cell water phosphates Constituent of nucleic acids, nucleotides, Phosphorus 3 (PO4) phospholipids, LPs, teichoic acids SO4. H2S. So, organic Constituent cvsteine. methionine Sulfur sulfur compounds glutathione. several coenzymes Potassium 1 Potassium salts Main cellular inorganic cation and cofactor for certain enzvmes Inorganic cellular cation. cofactor for certain Magnesium 0.5 Magnesium salts enzvmatic reactions Calcium Inorganic cellular cation, cofactor for certain Calcium salts enzymes and a component of endospores Component of cytochromes and certain Ir 0.2 Iron salts nonheme iron-proteins and a cofactor for some enzvmatic reactions
Environmental factors affecting growth of bacteria ●1. Nutrients ●2. Temperature 3. hydrogen ion concentration(ph) Oxygen Requirements:氧气、二氧化碳 ●5.0 smotic pressure渗透压
Environmental factors affecting growth of bacteria ⚫ 1. Nutrients ⚫ 2. Temperature ⚫ 3. hydrogen ion concentration ( pH ) ⚫ 4. Oxygen Requirements:氧气、二氧化碳 ⚫ 5. Osmotic pressure 渗透压