Chapter 4 -- Bacterial Taxonomy Flashcards
Bergey’s Manual of DETERMINATIVE Bacteriology
- Five volumes, covering ALL known prokaryotes
- based on PHENOTYPIC characteristics
- volumes determined by CELL WALL composition
- for MEDICAL USE, by doctors
- restricted to bacterial disease agents
Bergey’s Manual of SYSTEMIC Bacteriology
- five volumes
- based on GENOTYPE (rRNA) characteristics
- phylogenetic system (evolutionary relationships)
of note: 2nd edition – based on rRNA sequencing ONLY, so classified together b/c they have similar sequencing
Domain Archaea
“odd bacteria” – primitive, adapted to extreme habitats and modes of nutrition
– more closely r/t eukarya to to bacteria, contain unique genetic sequencing in their rRNA
Domain Bacteria
“normal bacteria”
- phylum proteobacteria (gram-negative cell walls - rickettsias, enterics, vibrios)
- phylum firmicutes (mainly gram-positive with low G+C content - bacillus, clostridium, staphylococcus, streptococcus)
- phylum actinobacteria (gram-postive with high G+C content - corynebacterium, mycobacterium, micrococcus, streptomyces)
- phylum chlamydiae (chlamydia, chlamydophila)
- phylum spirochaete (treponema, borrelia, leptospira)
Halophiles
part of Domain Archaea – lovers of salt
Acidophiles
part of Domain Archaea – lovers of acid
Thermophiles
part of Domain Archaea – lovers of heat
Rickettsias
- very tiny, gram negative bacteria
- rod shaped
- most are pathogens
- obligate intracellular pathogens (must be in a host cell)
- transmitted by arthropod vectors
- fever & rash
- Rickettsia rickettisii – spread by ticks - “Rocky Mountain spotted fever”
- Rickettsia prowazekii – spread by louse (lice) - “Epidemic Typhus”
Chlamydias
-tiny
-coccoid
-obligate intracellular parasites
-not transmitted by arthropods, but by air or contact, including sexual
-2 species:
1. Chlamydia trachomatis – urogenital infections, trachoma (preventable blindness), conjunctivits, pneumonia
2. Chlamydophila pneumoniae & psittaci
I \
bronchitis, pneumonia, sinusitis I
(occurs more in college students) I
I
/
pneumonia, spread by parrots and parakeets
Phenotype
usually observable things – these things are influenced by DNA & environment
Genotype
determined by DNA
Classification Criteria for Prokaryotes
Phenotypic: morphology, arrangement, staining, colony appearance, chemical reactions, serological analysis
Genotypic: genetic and molecular analysis