{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

lec 16 - Lecture 16 Organization and Function of the Genome...

Info iconThis preview shows pages 1–17. Sign up to view the full content.

View Full Document Right Arrow Icon
Lecture 16 Lecture 16 Organization and Function Organization and Function of the Genome of the Genome
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
What is a genome? What is a genome? The total DNA complement of a given organism Includes: chromosomes, plasmids, viral
Background image of page 2
Genomic Information Genomic Information • How large are microbial genomes? • How many genes are in microbial genomes? • How are the genes organized and where are they located with respect to one another? • How is gene expression regulated ? • What genes are involved in specific pathways ( i.e., degradation of certain compounds, development, pathogenesis, and more)
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
How does genome information benefit us? How does genome information benefit us? metabolic capabilities of an organism leads to the development of new therapeutic agents relevant for industrial and medical applications allows comparisons of different organisms furthers our understanding of how life has evolved
Background image of page 4
Gene Organization in Microbial Cells Composition Chromosome Size ( nt /genes) I. Viruses RNA/DNA (ss and ds) linear/circular ~10 3+ < 25 dsDNA II. Bacteria (& Archaea) circular* (1*) (haploid) + plasmids ~10 6 ~10 3 0.5 - 8 x10 6 III. Eukarya dsDNA linear (multiple) (haploid/diploid) + plasmids (rare) + organelle 10 3 -10 4 10 7 -10 8
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Viral Gene Organization - Very Diverse (5000-200,000nt) - Require host machinery for replication and expression - Very Few Genes (< 25, often overlapping) Naked Virus Enveloped Virus
Background image of page 6
Prokaryotic Gene Organization • Chromosome • Large, single copy, typically circular • nucleoid • housekeeping genes • Non-Chromosomal - Plasmid • small, circular (<10 4 bp) • replicate independent of chromosome • multicopy • “specialty genes” • Transposable elements
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Compaction of the Genome • In a “relaxed” state, the E. coli genome would occupy 10X its volume • Utilizes ATP-dependent Topoisomerases to compact the genome = “Supercoiling” • Proteins are involved in further formation of supercoiled domains
Background image of page 8
Supercoiling via Topoisomerase
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Gene organization in Prokaryotes - Operons • Genes with related functions are often grouped together • Transcribed as a single mRNA = polycistronic • Single promoter, several genes in mRNA = operon • Transcription & translation coupled
Background image of page 10
Eukaryotic Gene Organization • DNA enclosed in nucleus • Compaction occurs via topoisomerase and nucleosomes • Linear Chromosomes (centromeres/telomeres)
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Eukaryotic Gene Regulation • typically monocistronic • pre-mRNA contains introns • processing generates mature mRNA
Background image of page 12
Some stuff you should be familiar with... restriction enzymes plasmids / cloning plasmids / expression
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Some other stuff you should be familiar with... PCR DNA sequencing
Background image of page 14
Sequencing of Microbial Genomes
Background image of page 15

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Science 1995 Jul 28;269(5223):496-512 Whole-genome random sequencing and assembly of Haemophilus influenzae Rd .
Background image of page 16
Image of page 17
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}