Micro Bacteria Flashcards
1
Q
Gram negative proteobacteria (3 types)
A
alphaproteobacteria
betaprototeobacteria
gammaproteobacteria
2
Q
Alphaproteobacteria
A
-gram negative
-capable of growth in low levels of nutrients
-capable of nitrogen fixation in symbiosis with plants and several plant and human pathogens
3
Q
Genera of alphaproteobacteria
A
rickettsia and bartonella
4
Q
Rickettsia
A
- gram negative
- rod shapes or coccobacilli
- transmitted to humans by insects and tick bites
- enter host cell by inducing phagocytosis, enter cytoplasm of cell and begin reproducing binary fission
- responsible for spotted fever grop
- damage the permeability of blood capillaries which results in spotted rash
5
Q
Bartonella
A
- B. Henselea
- gram negative that causes cat scratch disease
- parinaud oculaoglandular syndrome
- presents neuroretniti with optic nerve edema, macular star formation, and discrete white retinal or choroid lesions
- alphaproteobacteria
6
Q
Betaproteobacteria
A
- overlaop with alpha
- use nutrient substances that diffuse away from areas of anaerobic decompision or organic matter such as H2 gas, ammonoa, and methane
7
Q
Genera of betaproteobacteria
A
bordetella and neisseria
8
Q
Bordetella
A
- betaproteobacteria
- nonmotile
-aerobic - gram negative rod
- bordetlla pertussis- whooping cough
9
Q
Neisseria
A
- aerobic
- gram negative cocci
- live in membranes of mammals
10
Q
Gammaproteobacteria
A
largest subgroup of proteobacteria
11
Q
Genera of gammaproteobacteria
A
pseudonomas, moraxella, acinetobacter, legionella, enterobacterialis
12
Q
Pseudonomas
A
- aerobic, gram negative rods
- motile by polar flagella
- P. aeruginoda can infect urinary ttacts, burns, and wounds, and can cause blood infections, abscesses, and meningitis
- can be resistant to antibiotics
13
Q
Moraxella
A
- gram negative
- strictly aerobic coccobacilli
- moraxella lacunta causes conjuctivitis
14
Q
Acinetobacter
A
- gram negativ
- aerobic
- typically form in pairs
- A. baumanii
15
Q
A. baumanii
A
- common in healthcare setting
- becoming more resistant to antibiotics
- primatily respitory pathogen
- high mortlality rate due to resistance
- acinetobacter
16
Q
Legionella
A
- gram negative
- common in streams, warm water supply lines, and water in air conditioning systems
- hard to eradicate
17
Q
Enterobacterialis
A
- known as enterics
- faculative anaerobes
- gram -
- if motile: peritrichously flagellated
- inhabit animal intestines
- have fimbriae that help attach to surfaces
- produce bacteriocins that cause lysis of other bacteria
18
Q
Nonproteobacteria gram negative groups
A
cyanobacteria
chlamydia
spirochetes
19
Q
Cyanobacteria
A
Carry out oxygenic photosynthesis
* Capable of fixing nitrogen
* Types:
* unicellular forms that divide by binary fission
* colonial forms that divide by multiple fission
* Filamentous forms that reproduce by fragmentation of the filaments
20
Q
Chlamydia
A
- Gram-negative coccoid
- Most distinguished by their unique developmental cycle
- Their elementary body is the infective agent.
- Transmitted by interpersonal contact
- 3 species significant for pathogens
- C. trachomatis – trachoma - causes blindness, nongonococcal urethritis (STI) and lymphogranuloma venereum (STI)
- Related to Chlamydophila genus that can cause airborne respiratory disease
21
Q
Spirochetes
A
- Develop axial filaments
- gram negative
- Helps in motility. Can move 100 times its body length in a second
- Can be found in human oral cavity
- Genera: Treponema and Borrelia
22
Q
Treponema
A
*gram negative
* Includes many important pathogenic bacteria
* Treponema pallidum
*causes syphilis
23
Q
Borrelia
A
- Borrelia burgdorferi causes Lyme disease
- Most often in Northeast, mid-Atlantic, upper Midwest areas of the U.S.
- Carried by ticks
- Causes: fever, rash, facial paralysis, an irregular heartbeat,
and arthritis (CDC)
gram negative
24
Q
Gram Positive types
A
Firmicutes and actinobacteria
25
Q
Firmicutes
A
- Low G + C gram positive bacteria
- Endospore forming
- Genera:
- Clostridium
- Bacillus
- Staphylococcus * Enterococcus
- Streptococcus
- Listeria
- Mycoplasmas
26
Q
Clostridium
A
- Obligate anaerobes
- Rod shaped
- Usually contain endospores * C. tetani, botulinum, difficile
27
Q
Bacillus
A
- gram positive
- Rods
- Produce endospores
- Common in soil
- Few are pathogenic to humans
- Serval are used to produce antibiotics * B. anthracis
- Nonmotile facultative anaerobe
- cause of anthrax in cattle, sheep, humans
28
Q
Staphylococcus
A
- gram positive
*Grapelike clusters - S. aureus names for its yellow pigmented colonies
- Facultative anaerobes
- Grow well under high osmotic pressure and low moisture
- Carried in our noses and on skin
- Can infect surgical wounds
- Can be resistant against penicillin
- Produce toxins responsible for toxic shock syndrome
- Produced enterotoxins – one of the most common causes of food
poisoning
29
Q
Enterococcus
A
- gram positive
- Well-adapted to areas of the body that are rich in nutrients, but low in oxygen like the GI and oral cavity.
- Can be found in human stool.
- High resistance to antibiotics
- Known for many surgical wounds and urinary tract infections
- Enter bloodstream through invasive procedures such as
indwelling catheters
30
Q
Streptococcus
A
- Spherical chains
- Gram-positive
- Causative of a greater variety of diseases more than other groups of bacteria
- Produce extracellular substances that destroy phagocytic cells and produce enzymes that digest host’s connective tissue.
- Bacterial enzymes digest the fibrin of blood clots, so infections spread
31
Q
Listeria
A
- gram positive
- L. monocytogenes contaminate food especially dairy products
- Survives within phagocytic cells and is capable of growth at refrigeration temperatures.
- Can cause stillbirth or serious damage to the fetus of pregnant women
32
Q
Mycoplasma
A
- Polymorphic
- Lack a cell wall
- Can produce filaments thar resemble fungi (mykes=fungus, plasma=formed)
- Very small 0.1 to 0.25 microns; cell volume 5% of the typical bacillus
- Smallest self-replicating organism capable of free-living existence.
- Related to gram-positive bacteria like Bacillus and Streptococcus but have lost genetic material over time in a process called degenerative evolution.
- Special in that their cell membranes contains sterols unlike other prokaryotes
- M. pneumoniae – cause of mild pneumonia
33
Q
Actinobacteria
A
- gram positive
*High G+C gram-positive bacteria - Actino means ray
- Referring to a radiate or starlike form of growth by often branching filaments
- Morphology resembles that of filamentous fungi
- Allows for a higher surface-to-volume ratio and enhances absorbing nutrients
- Their filaments have a diameter much smaller than that of eukaryotic molds
- Some carry asexual spores that are used for reproduction
- Genera:
- Mycobacterium
- Corynebacterium * Actinomyces
34
Q
Mycobacterium
A
- gram positive
*Aerobic, non-endospore forming rods - Myco (fungus-like) because of the occasional exhibition of filamentous growth
- Acid-fast stain, drug resistance, pathogenicity all related to their distinctive cell wall containing mycolic acid forming a waxy, water-resistant layer
- Cell wall causes resistance to stresses like drying and antimicrobials to enter the cell, but also slows down the entrance of nutrients thus the slow growth rate of the bacteria
- M. tuberculosis causes TB
- M. leprae causes leprosy
- Two distinct groups:
- Slow growing – more pathogenic
- Rapid growers – mostly infectious to wounds but tend to be more nonpathogenic soil and
water microbes
35
Q
Cornyebacterium
A
- Coryne = Club-shaped
- Pleomorphic
- C. diphtheriae causes diphtheria
- gram positive
36
Q
Actinomyces
A
- Facultative anaerobes
- Live in the mouth and throat of humans
and animals - Occasionally form filaments that can fragment
- Actinomyces israelii – causes actinomycosis
- Tissue -destroying disease affecting the head, neck, or lungs
- Can csue multiple eye conditions including canaliculitis
- gram positive
