Presentation is loading. Please wait.

Presentation is loading. Please wait.

Bacterial Physiology (Micr430)

Similar presentations

Presentation on theme: "Bacterial Physiology (Micr430)"— Presentation transcript:

1 Bacterial Physiology (Micr430)
Lecture 13 Bacterial Genomics and Functional Genomics (from various sources)

2 Genome and Proteome Genome: The complete genetic information carried by an organism Proteome: Encompasses all the expressed proteins of an organism (protein array) Gene array: an orderly array of sequence tags each specific for one gene of a genome; (other names: gene chip, DNA microchip)

3 Genomics and Functional Genomics
Genomics: The study of all of the nucleotide sequences, including structural genes, regulatory sequences, and noncoding DNA segments, in the chromosomes of an organism Functional genomics: the branch of genomics that determines the biological function of the genes and their products

4 Protein array

5 Gene Array or DNA microaray
There are two main applications Identification of gene or mutation Determination of expression level of genes There are two formats: cDNA (500 – 5000 bp) molecules are spotted on the chip Array of oligonucleotides are synthesized and immobilized on the chip

6 Gene Array or DNA microarray
1) Probe (cDNA/oligo with known identity) 2) Chip fabrication (Putting probes on the chip) 3) Target (fluorecently labeled sample) 4) Assay 5) Readout 6) Informatics



9 DNA microarray applications
Gene discovery Study of gene functions and expression Study relationship of genes Disease diagnostics – infectious diseases

10 Study of gene function Gene replacement (knock-out): also known as reverse genetics. The purpose is to remove (knock-out) most of one gene and see what happens to the phenotype of the organism. Suicide vector is used Transposon mutagenesis. Similar to above but is more random disruption of genes.


12 Study of gene function Antisense RNA expression. Random cloning and expression of short pieces of genomic DNA on a plasmid in an microorganism to elucidate the function of the genes Essential gene: a gene whose function is absolutely required for the growth and survival of a cell.

13 Conditional Antisense Inhibition of Protein Synthesis
Inducible promoter Normal cell Antisense cell Plasmid DNA No protein Protein Antisense RNA X mRNA mRNA DNA DNA

14 Shotgun Antisense Expression Determines Essentiality of Genes
Pathogen genome Millions of random DNA fragments Non essential gene blocked by antisense Essential gene No cell growth mRNA Essential Protein DNA

15 Ultra-Rapid Functional Genomics
Identify >100 essential gene drug targets per month Antisense (+ inducer) No antisense (- inducer)

16 Traditional Tools Reporter gene: A gene whose product can be easily assayed Transcriptional gene fusions Translational gene fusions PCR DNA Mobility Shift


18 PCR

19 Gel Shift Assay

Download ppt "Bacterial Physiology (Micr430)"

Similar presentations

Ads by Google