Lecture 31 - Bacterial Classification

Question 1

what are the morphological categories of bacteria

Answer 1

1. cocci
2. bacilli (rods)
3. budding/appendaged
4. other

Question 2

pathogenicity

Answer 2

potential for bacteria to cause disease

Question 3

how is morphology measured

Answer 3

microscopy (flow cytometry) at low resolution

Question 4

how is pathogenicity measured

Answer 4

patient symptoms

Question 5

heterotrophs

Answer 5

grow on organic compounds

Question 6

aerobes

Answer 6

require oxygen; respiration

Question 7

anaerobes

Answer 7

don’t need oxygen; fermentation or incomplete respiration

Question 8

phototrophs

Answer 8

energy from light

Question 9

autotrophs

Answer 9

inorganic compounds w/o light

Question 10

how are bacterial metabolisms measured

Answer 10

culture at low/moderate resolution

Question 11

describe the cell structure (outermost to innermost)

Answer 11

capsule - pilus or flagella
cell wall
plasma membrane
cytoplasm - ribosomes and nucleoid

Question 12

how is cell structure measured

Answer 12

microscopy (+ staining), motility tests, protein content

Question 13

what is the Linnaean taxonomy

Answer 13

kingdom
phylum
class
order
family
genus
species

Question 14

T/F: genus-species naming is used in clinical settings as it provides the best description of bacteria

Answer 14

TRUE

Question 15

T/F: subspecies definitions are standardized

Answer 15

FALSE

Question 16

what are the takeaways from the history of bacterial taxonomy

Answer 16

• continuously changing field
• product of history, methodology, and concepts
• genomics and phylogeny will shape future

Question 17

selective culture

Answer 17

media that allows for the growth of bacteria w specific metabolic traits, can test AMR

Question 18

Protein content

Answer 18

mass spectrometry results compared to reference database
fast and inexpensive after colonies obtained
resolution limited

Question 19

Targeting genes

Answer 19

PCR

Question 20

Whole genome sequencing

Answer 20

the complete genome of bacterial isolates, as long as the culture was successful

maximum resolution

Question 21

What diagnostic would be used to answer the question:

Is the infection caused by pathogen A or pathogen B?

Answer 21

selective culture

Question 22

What diagnostic would be used to answer the question:

Is this outbreak connected to that previous outbreak?

Answer 22

whole genome sequencing