1. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings 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 A 8 Microbial Genetics

2. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings  Genetics: The study of what genes are, how they carry information, how information is expressed, and how genes are replicated.  Gene: A segment of DNA that encodes a functional product, usually a protein. Terminology

3. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings  Genome: All of the genetic material in a cell  Genomics: The molecular study of genomes  Genotype: The genes of an organism  Phenotype: Expression of the genes Terminology

4. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings E. coli Figure 8.1a

5. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Chromosome Map Figure 8.1b

6. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Flow of Genetic Information Figure 8.2

7. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings DNA  Polymer of nucleotides: Adenine, thymine, cytosine, and guanine  Double helix associated with proteins  "Backbone" is deoxyribose- phosphate  Strands are held together by hydrogen bonds between AT and CG.  Strands are antiparallel. Figure 8.3b

8. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings DNA Figure 8.3a

9. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings DNA Figure 8.4

10. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings DNA  DNA is copied by DNA polymerase  In the 5'  3' direction  Initiated by an RNA primer  Leading strand is synthesized continuously  Lagging strand is synthesized discontinuously  Okazaki fragments  RNA primers are removed and Okazaki fragments joined by a DNA polymerase and DNA ligase

11. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Important Enzymes Table 8.1

12. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings DNA Replication Figure 8.5

13. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings DNA  DNA replication is semiconservative. Figure 8.6

14. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Transcription  DNA is transcribed to make RNA (mRNA, tRNA, and rRNA).  Transcription begins when RNA polymerase binds to the promotor sequence  Transcription proceeds in the 5'  3' direction  Transcription stops when it reaches the terminator sequence PLAY Animation: DNA Replication

15. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Transcription Figure 8.7 (1 of 2)

16. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Transcription PLAY Animation:Transcription Figure 8.7 (2 of 2)

17. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings RNA processing in Eukaryotes Figure 8.11