Bacterial Identification

Question 1

16S rDNA (identification)

Answer 1

Universal & conserved - present in nearly all bacteria

Conserved - tiny variation from cell to cell even over time

Taxonomy, relationships, tracking divergence from ancestors

Question 2

Ribsomes are locations for

Answer 2

Protein synthesis in Prokaryotes

Question 3

1. Extracting DNA

Answer 3

Dissolving cell wall with proteolytic enzymes (digestive enzymes)

Question 4

2. PCR

Answer 4

Polymerase Chain RXN

Take small sample of DNA and produce multiple copies/amplify

Question 5

Steps of PCR

Answer 5

1. Denature at high heat 95 degrees
2. Anneal - lower temp, primers bind to each separate strand at 60 degrees
3. Extension - DNA polymerase extends primers to form a new copy strand from original/template strand - 72 degrees

Question 6

Why is Taq Polymerase used

Answer 6

Heat stable - can withstand first step

Question 7

Primers

Answer 7

Tiny lengths of DNA that interact with sequences of gene

Question 8

3. DNA sequencing goal

Answer 8

Separate DNA and identify order of nucleotides withe fluorescent markers

Gel electrophoresis and computer assembly of sequences used

Question 9

BLAST

Answer 9

Basic search tool - allows for gene sequence of unknown org to be compared with database of identified or known orgs

Correctly identify unknown org through comparison : max percentage, low E - value, gap percentage at 0 or close