1. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture Slide Presentation prepared by Christine L. Case M I C R O B I O L O G Y a n i n t r o d u c t i o n ninth edition TORTORA  FUNKE  CASE Part B 2 Chemical Principles

2. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings  Organic compounds always contain carbon and hydrogen.  Inorganic compounds typically lack carbon. Important Biological Molecules

3. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Inorganic Compounds: Water  Polar molecule Figure 2.4a

4. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Inorganic Compounds: Water  Solvent  Polar substances dissociate, forming solutes. Figure 2.5

5. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Inorganic Compounds: Water  Hydrogen bonding between water molecules makes water a temperature buffer. Figure 2.4b

6. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Acids, Bases, and Salts  An acid is a substance that dissociates into one or more H +. HCl  H + + Cl  Figure 2.6a

7. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Acids, Bases, and Salts  A base is a substance that dissociates into one or more OH . NaOH  Na + + OH  Figure 2.6b

8. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Acids, Bases, and Salts  A salt is a substance that dissociates into cations and anions, neither of which is H + or OH . NaCl  Na + + Cl  Figure 2.6c

9. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 2.6 - Overview

10. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Acid-Base Balance  The amount of H + in a solution is expressed as pH.  pH =  log[H + ]  Increasing [H + ], increases acidity.  Increasing [OH  ] increases alkalinity.  Most organisms grow best between pH 6.5 and 8.5.

11. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Acid-Base Balance Figure 2.7

12. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 2.7 (2 of 5)

13. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 2.7 (3 of 5)

14. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 2.7 (4 of 5)

15. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Organic Compounds  Carbon skeleton  Functional groups

16. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Table 2.3 (1 of 2)

17. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Table 2.3 (2 of 2)

18. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Organic Compounds  Macromolecules are polymers consisting of many small repeating molecules.  The smaller molecules are called monomers.

19. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Carbohydrates  Are important for structure and as energy sources.  Consist of C, H, and O with the formula (CH 2 O) n. Figure 2.8

20. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Carbohydrates  Monosaccharides are simple sugars with three to seven carbon atoms. Figure 2.8

21. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Carbohydrates  Disaccharides are formed when two monosaccharides are joined in a dehydration synthesis.  Disaccharides can be broken down by hydrolysis. Figure 2.8

22. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Carbohydrates  Polysaccharides consist of tens or hundreds of monosaccharides joined through dehydration synthesis.  Starch, glycogen, dextran, and cellulose are polymers of glucose that are covalently bonded differently.  Chitin is a polymer of two sugars repeating many times.

23. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Lipids  Are the primary components of cell membranes.  Consist of C, H, and O.  Are nonpolar and insoluble in water.

24. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Simple Lipids  Called fats or triglycerides; contain glycerol and fatty acids; formed by dehydration synthesis.  Unsaturated fats have one or more double bonds in the fatty acids. Figure 2.9c

25. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Complex Lipids  Membranes are made of phospholipids. Figure 2.10a

26. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 2.10b

27. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 2.10c

28. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Steroids  Consist of four carbon rings with an –OH group attached to one ring.  Are part of membranes. Figure 2.11

29. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Proteins  Are essential in cell structure and function.  Enzymes are proteins that speed chemical reactions.  Transporter proteins move chemicals across membranes.  Flagella are made of proteins.  Some bacterial toxins are proteins.

30. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 2.12a

31. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 2.12 - Overview

32. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Proteins  Consist of subunits called amino acids. Table 2.4 (1 of 4)

33. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Proteins Table 2.4 (2 of 4)

34. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Proteins Table 2.4 (3 of 4)

35. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Proteins Table 2.4 (4 of 4)

36. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Peptide Bonds  Peptide bonds between amino acids are formed by dehydration synthesis. Figure 2.14

37. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Levels of Protein Structure  The primary structure is a polypeptide chain. Figure 2.15a

38. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Levels of Protein Structure  The secondary structure occurs when the amino acid chain folds and coils in a regular helix or pleats. Figure 2.15b

39. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Levels of Protein Structure  The tertiary structure occurs when the helix folds irregularly, forming disulfide bonds, hydrogen bonds, and ionic bonds between amino acids in the chain. Figure 2.15c

40. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Levels of Protein Structure  The quaternary structure consists of two or more polypeptides. Figure 2.15d

41. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Level of Protein Structure  Conjugated proteins consist of amino acids and other organic molecules  Glycoproteins  Nucleoproteins  Lipoproteins

42. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Nucleic Acids  Consist of nucleotides.  Nucleotides consist of a  Pentose  Phosphate group  Nitrogen-containing base Figure 2.16 (1 of 2)

43. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings DNA  Has deoxyribose  Exists as a double helix  A hydrogen bonds with T  C hydrogen bonds with G Figure 2.16 (2 of 2)

44. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings RNA  Has ribose  Is single-stranded  A hydrogen bonds with U  C hydrogen bonds with G Figure 2.17