Microbial Classification and Identification

Flashcards about Microbial Classification and Identification

What are the three components of taxonomy?

Classification, Identification, and Nomenclature

Who proposed the three domains of life based on 16S rRNA sequence analysis?

Carl Woese

What are the three domains of life?

Archaea, Bacteria, and Eucarya

What type of characteristics are used in phenetic classification?

Morphological, physiological, and ecological characteristics

What is the primary basis for plant and animal classification?

Phenetic classification

What type of information is used in phylogenetic analyses?

Evolutionary relationships

What is cladistics?

The field of study where organisms are grouped based on evolutionary relationships.

Name two biochemical characteristics used in microbial classification.

Proteins and Fatty acids

What analytical technique is used to analyze proteins for classification

Mass-spectrometry (MALDI-ToF)

What analytical technique is used to analyze fatty acids for classification

Fatty acid methyl ester (FAME) analysis

What genetic element is sequenced in genetic (sequence) characteristics

Specific genes

What is an allele?

Gene variant

What is the average gene size for prokaryotes?

~950 base pairs

What is the average gene size for eukaryotes?

~1350 base pairs

What is a highly conversed gene?

Genes that are found in all organisms with the same function and essential role

Give an example of a highly conserved gene.

16S ribosomal rRNA gene

What is a consensus sequence?

The nucleotides most commonly present at a specific position in the nucleic acid after analysis of the sequences of many organisms

What are deviations from a consensus sequence called?

Signature sequences

What does the length of a branch indicate in a phylogenetic tree?

The number of changes between two nodes

What does ANI stand for?

Average Nucleotide Identity

What level of identification is useful for 16S rRNA?

Genus level

What level of identification is useful for Whole Genome Sequencing?

Species level

What is the minimum percentage of ANI needed to have the same organism?

95-96% ANI

What is being replaced by ANI?

DNA