Table of Contents
- 1 When determining which species of fungus is the closest match to the sequence of your PCR product the most useful information is provided by the?
- 2 What is a nucleotide blast and how can it be used to determine the identity of the unknown invertebrate?
- 3 Why is it important to remove excess ns from the end of the sequences?
- 4 What might it mean when there are multiple BLAST hits with similar e values?
When determining which species of fungus is the closest match to the sequence of your PCR product the most useful information is provided by the?
In general bootstrap values above 70 might be considered as plausible given the data, and above 95 can be considered “correct.”…II. Determine Sequence Relationships Using the Blue Line.
| Phred Score | Error | Accuracy |
|---|---|---|
| 30 | 1 in 1,000 | 99.9\% |
| 40 | 1 in 10,000 | 99.99\% |
| 50 | 1 in 100,000 | 99.999\% |
What is a nucleotide blast and how can it be used to determine the identity of the unknown invertebrate?
BLASTn (Basic Local Alignment Search Tool) is a database that compares your nucleotide sequence to all other nucleotide sequences in the NCBI database and then identifies sequences that share regions of homology with your sequence.
What might it mean when there are multiple blast hits with similar e values?
What does it mean when there are multiple BLAST hits with similar E-values? The lower the E-value, the lower the probability of a random match and the higher the probability that the BLAST hit is related to the query.
Why still accurate fungal PCR diagnostics are not available?
PCR is a very appealing technology for the detection of human pathogens, but the detection of fungal pathogens is particularly challenging. Fungi have cell walls that impede the efficient lysis of organisms and liberation of DNA, which can lead to false-negative PCR results.
Why is it important to remove excess ns from the end of the sequences?
Why is it important to remove excess Ns from the ends of the sequences? Each “N” is scored as a misalignment, causing experimental sequences to appear to be less related to reference sequences than they actually are.
What might it mean when there are multiple BLAST hits with similar e values?
Why do scientists all over the world check BLAST when they sequence a new region of DNA?
The comparison of nucleotide or protein sequences from the same or different organisms is a very powerful tool in molecular biology. By finding similarities between sequences, scientists can infer the function of newly sequenced genes, predict new members of gene families, and explore evolutionary relationships.
How does DNA hybridization work?
Hybridization of DNA is accomplished by heating strands of DNA from two different species to 86° C [186.8° F]. This breaks the hydrogen bonds between all complementary base pairs. The resulting hybrid DNA is then reheated and the temperature at which the DNA once again becomes single-stranded is noted.