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
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
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
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings E. coli Figure 8.1a
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Chromosome Map Figure 8.1b
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Flow of Genetic Information Figure 8.2
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
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings DNA Figure 8.3a
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings DNA Figure 8.4
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
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Important Enzymes Table 8.1
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings DNA Replication Figure 8.5
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings DNA DNA replication is semiconservative. Figure 8.6
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
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Transcription Figure 8.7 (1 of 2)
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Transcription PLAY Animation:Transcription Figure 8.7 (2 of 2)
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings RNA processing in Eukaryotes Figure 8.11