Chemical and Genetic Aspects of Microorganisms

• microorganism


  can be thought of as a “bag” of chemicals that interact with each other in a variety of ways; even the bag itself is composed of chemicals
• organic chemistry


  study of compounds that contain carbon
• inorganic chemistry


  involves all other chemical reactions
• biochemistry

  the chemistry of living cells—the chemistry of life
• organic compounds


  compounds that contain carbon
• Organic chemistry


  this branch of chemistry involves fossil fuels, dyes, drugs, paper, ink, paints, plastics, gasoline, rubber tires, food, and clothing
• single bond, double bond, and triple bond


  three ways in which carbon atoms can bond to each other
• covalent bond


  a way in which a pair of electrons is shared
• compounds


  these are formed when atoms of other elements attach to available carbon bonds
• 4

  valence of carbon atoms
• chain


  series of carbon atoms bonded together
• hydrocarbons

  these are formed only when hydrogen atoms are bonded to the available carbon bonds
• hydrocarbons

  an organic molecule that contains only carbon and hydrogen atoms
• Biochemistry


  the study of biology at the molecular level
• biochemistry

  involves the study of biomolecules present within living organisms
• macromolecules

  biomolecules in living organisms that are usually large molecules
• nutrients

  used in metabolic reactions as sources of energy and as “building blocks” for enzymes, structural macromolecules, and genetic materials
• carbohydrates

  biomolecules composed of carbon, hydrogen, and oxygen in the ratio 1:2:1
• monosaccharides, disaccharides, and polysaccharides


  Categories of carbohydrates
• monosaccharides


  the smallest and simplest of the carbohydrates
• glucose


  the most important monosaccharide in nature, which may occur as a chain or in alpha or beta ring configurations
• triose


  three-carbon monosaccharide
• tetrose

  four-carbon monosaccharide
• pentose


  five-carbon monosaccharide
• hexose

  six-carbon monosaccharide
• heptose


  seven-carbon monosaccharide
• a-glucose, straight-chain form, and b-glucose


  main source of energy for body cells
• ATP


  main energy source used to drive most metabolic reactions
• glucose


  in humans, this is carried in the blood to cells where it is oxidized to produce energy-carrying ATP
• disaccharides


  are double-ringed sugars that result from the combination of two monosaccharides
• dehydration synthesis reaction


  removal of a water molecule in the combination of two monosaccharides
• hydrolysis reaction

  a process where disaccharides interact with water, causing them to break down into two monosaccharides
• peptidoglycan


  a repeating disaccharide attached by proteins to form a lattice that surrounds and protects the bacterial cell.
• trisaccharides

  Carbohydrates composed of three monosaccharides
• tetrasaccharides


  Carbohydrates composed of four monosaccharides
• pentasaccharides


  Carbohydrates composed of five monosaccharides
• polysaccharides


  carbohydrates that are composed of many monosaccharides
• polysaccharides


  functions as a storage of energy and can provide a “tough” molecule for structural support and protection
• polymer


  molecules that consist of many similar subunits
• lipids

  most are insoluble in water, but soluble in fat solvents, such as ether, chloroform, and benzene