Claudia Campos Week 7

10 Biological Terms

1. gavage: force feeding by means of a tube
2. motif: a distinctive usually recurrent molecular sequence (as of amino acids or base pairs) or structural elements (as of secondary protein structures)
3. chemotactic: the movement of a microorganism or cell in response to a chemical stimulus
4. downregulation: a decrease in sensitivity, through overexposure, to a drug or other chemical caused by a reduction in the number or density of receptors on cell surfaces
5. linker proteins: proteins that provide mechanisms by which receptors can amplify and regulate downstream effector proteins
6. hyperinfectious: repeated reinfection with larvae produced by parasitic worms already in the body due to the ability of various parasites to complete the life cycle within a single host compare
7. locus: the chromosomal position of a gene as determined by its linear order relative to the other genes on that chromosome
8. serotype: a group of organisms, microorganisms, or cells distinguished by their shared specific antigens as determined by serologic testing
9. inoculate: to implant (a disease agent or antigen) in a person, animal, or plant to produce a disease for study or to stimulate disease resistance
10. precipitation: the precipitating of a substance from a solution
11. precipitate: to separate (a substance) in solid form from a solution, as by means of a reagent

Outline: Host-induced epidemic spread of the cholera bacterium

• Main Result: Having more information and higher understanding of gene expression will give the ability to develop antimicrobial therapies and control transmission of the microbial infections and also develop vaccines to give immunity.
• Comparing in vitro grown strains of V. cholerae and human-shed stool samples containing V. cholerae.
• Methods
  • Sample Collection: Stool samples gotten from patients at the ICDDR and pre-screened to make sure V. cholerae was present.
  • Competition Assays: Small intestines from euthanized animals plated to see LacZ+ and LacZ- colonies.
  • Microarray Analysis: Amplified ORFs using PCR. Array had 5,222 spots representing 3,357 ORFs. Labelled with Cy5 and Cy3 and performed in duplicate on two different days. This gave quadruplicates for each strain of collected stool sample or in vitro sample.
• Figure 1: Human-shed V. cholerae are hyperinfectious in competition assays as seen in infant mice stool derivations
• Figure 2: Transcription profile of human-shed V. cholerae seen in a cluster diagram

Claudia Campos