BIOL 2460 chapter 4

Where can prokaryotes be found?

Everywhere. (Bacteria & Archaea) are

ubiquitous (Hot springs, Ice caps, Deep ocean, Skin & mucosal surface)

Mutualism

both organisms benefit (Gut nutrient metabolism)

Amenalism

one population is inhibited or harmed by a second population that is not affected (Antimicrobial defense on skin)

Commensalism

one organism benefits and the other is unaffected (Skin cells as food source)

Neutralism

Neither species benefits or is harmed (Spores in soil)

Parasistism

One organism benefits and the other is harmed (Tuberculosis, leprosy, etc.)

Microbiome

all of the microorganisms that live in a particular environment (prokaryotes + eukaryotes microbes + genetic)

Polymicrobial

more than one type of organism present simultaneously

-Cooperative: work together (biofilm formation)

-Competing: work against each other (scarce resources)

Resident microbiome

Remain part of the normal flora throughout life of a person

Transient microbiome

Only remain in the body for a few hours, days, or months before they vanish

Prokaryotes produce

asexually

Oligotrophs

organisms capable of living in a low-nutrient environment. Chlamydia & Rickettsia

Rickettsia spp.

causative agents for Rocky Mountain spotted fever & typhus fevers, Gram-negative, highly pleomorphic bacteria (maybe cocci, rods, or threads)

Chlamydia spp.

causative agents for lymphogranuloma venereum (STD), the clam, Gram-negative, coccoid or ovoid bacterium

Eutrophs

require many nutrients (copiotrophs). Bordetella & Neisseria

Neisseria gonorrhea

causative agent for gonorrhea STD

Neisseria meningitides

causative agent for bacterial meningitis

Bordetella spp

causative agents whooping cough (pertussis) & kennel cough Produces toxins to paralyze lung cilia

Pseudomonas aeruginosa

Common infection of wounds, urinary tract, & respiratory tract

Pasteurella haemolytica

Causative agent for severe pneumonia in animals

Haemophilus influenza

causative agent for upper & lower respiratory infections (does not cause influenza)

Vibrio spp.

commonly found in alkaline environments such as ocean ports & lagoons

- gastrointestinal disease, cellulitis, blood-borne infections

Vibrio cholera

causative agent of cholera and common to water contamination

Legionella pneumophila

causative agent for Legionnaire's disease and common to water contamination (water cooler, shower head, air conditioning)

Coliforms

"E. coli - like" microbes that ferment lactose completely. produce both acid AND gas. (enterobacter family)

Noncoliforms

Fermentation of lactose is incomplete or absent. Produce acid OR gas.(enterobacter family)

E. coli

most mutualistic, some produce Shiga toxin

Salmonella

can have multiple serotypes, many that cause salmonellosis

Desulfovibrio orale

periodontal disease. Reduce sulfur; can be used for removal of toxic and radioactive waste.

Parasitic Bdellovibrio spp.

Infect other bacteria

Myxobacteria "slime bacteria"

Live in soil; can move by gliding; used as a model organism for studies of intercellular communication (signaling)

Campylobacter spp.

common to food poisoning

Helicobacter spp.

Commonly beneficial but can cause ulcers and stomach cancer in susceptible people

Alphaproteobacteria

Rickettsia and Chlamydia

Betaproteobacteria

Eutrophs: Bordetella & Neisseria

Gammaproteobacteria

Pseudomonas, Pasteurella, Haemophilus,Vibrio, Legionella, Enterobacter family

Deltaproteobacteria

Relatively small class, includes:

• Sulfate reducing bacteria

• Desulfovibrio orale - periodontal disease

• Parasitic Bdellovibrio spp.

• Soil dwelling Myxobacteria "slime bacteria

Epsilonproteobacteria

Smallest class, microaerophilic

• Prominent genera: Campylobacter & Helicobacter

Spirochetes

Gram (-) extremely thin and hard to stain & culture

• have axial filament similar to flagella

• Treponema pallidum

• Borrelia burgdorferi

Treponema pallidum

causative agent for syphilis

Borrelia burgdorferi

Lyme disease

The CFB Group

Cytophaga, Fusobacterium, and Bacteroides (rod-shaped anaerobic organoheterotrophs and avid fermenters)

Cytophaga spp

Gliding system for motility (mechanisms mostly unknown)

Fusobacteria spp.

Inhabit mouth and can cause various oral diseases

Bacteroides spp.

30% of gut microbiome; lower levels correlated with obesity. Digest fiber and improve gut lining.

Planctomycetes

Found in aquatic environments: fresh, salt, and brackish, reproduce via budding instead of binary fission

Sessile cells

immobile with holdfast appendage

Swarmer cells

motile, unable to reproduce

Phototrophic Bacteria

Grouped based on function, not taxa, utilize sunlight as main source of energy via photosynthesis.( oxygenic-= poduce 02, -Anoxygenic= do not produce 02).

Cyanobacteria

highly adaptable and diverse; chlorophyll; uses as biosorbents and human nutrition

Microsystis spp.

toxic algal blooms

Anoxygenic photosynthesizers

Purple Sulfur, Purple Non-Sulfur, Green Sulfur, and Green Non-Sulfur

Oxygenic Photosynthesizer

cyanobacteria

Phylum Actinobacteria

Gram-positive with high G + C content.Thin, filamentous to coccobacilli shaped

•Important to soil ecology

•Different peptidoglycans in cell wal

(Mycobacterium

Corynebacterium, Bifidobacterium, Gardnerella)

Phylum Firmicutes

mainly Gram-positive with low G + C content, (Clostridium, Streptococcus, Lactobacillus, Enterococcus, Bacillus, Staphylococcus)

Mycobacterium spp.

Acid fast (+) due to mycolic acid in cell wall; causative agent for tuberculosis & leprosy

Corynebacterium spp.

Diaminopimelic acids in cell wall; Most are non-pathogenic; C. diphtheria is causative agent for diphtheria

Bifidobacterium spp.

Filamentous & anaerobic; Frequently used as probiotic

Gardnerella vaginalis

Only one species, Gram variable: inconsistent stain results,

Causative agent for bacterial vaginosis

Genus Clostridium

mostly obligate anaerobes, Endospore producers, Soil dwelling, Common food contaminant

C. perfringens

agent for food poisoning and gangrene

C. tetani

producer of neurotoxin and agent for tetanus. Spastic paralysis

C. botulinum

producer of botulinum neurotoxin. flaccid paralysis. Botox

C. difficile

hospital infection, causes severe colitis

Order Lactobacillales

contains bacilli & cocci

S. pyogenes

β-hemolytic cocci associated with pus production (pyogenic), strep throat

S. pneumoniae

causes pneumonia, respiratory infections, and a wide range of other diseases

Lactobacillus

Facultative anaerobes, non-spore formers, significant component of gut microbiome, starter cultures for yogurt, cheese, sauerkraut, etc.

Enterococcus

Diplicocci arrangement, Anaerobic respiration, gut microbe, Common UTI pathogen (E. faecium)

Genus Bacillus

bacillus shaped aerobes or facultative anaerobes, Endospore producers, Important to industrial microbiology

B. anthracis

causative agent for anthrax

B. cereus

common food poisoning agent

B. thuringiensis

producer of insecticide compounds

Genus Staphylococcus

cocci shaped; facultative anaerobes; halophilic; nonmotile

S. aureus

common agent of skin infections; some can produce enterotoxins for food poisoningSome are very antibiotic resistant (MRSA & VRSA)

S. epidermidis

common flora on skin; can cause infection to open wounds

Genus Mycoplasma

-no cell wall/do not retain crystal violet

-pleomorphic

-Extremely small

-Cell wall antibiotics do not work

-Only classified by genome

M.pneumoniae

M. pneumoniae

agent for walking pneumonia

Deeply Branching Bacteria

Genera and species that are most common to the last universal common ancestor (LUCA). (Aquicae, Thermotogae, Deinocci

Aquificae

gram (-) hyperthermophiles living in hot springs and oven vents

Thermotogae

gram (-), hyperthermophilic anaerobes; sheath-like outer membrane

Deinococci

gram (+) polyextremophile (heat, vacuum, acidity tolerant)

Archaea

Membranes with branched isoprene chains & ether linkages to phosphate head, Walls of surface layer proteins(some pseudo peptidoglycan), Genomes are much larger, Capable of methanogenesis, Usually not in human microbiota, Not directly associated with infectious diseases

Phylum Crenarchaeota

All aquatic microbes, many extremophiles. Domain: archia

Sulfolobus spp.

thermophiles & acidophiles; facultative anaerobic; used in biotech for production of affitins

Thermoproteus spp.

strict anaerobic thermophiles; arguably deepest branching Archaea

Phylum Euryarchaeota

- Mostly methanogens and anaerobes

- Prominent classes: Methanobacteria, Methanococci, Methanomicrobia, Halobacteria

Gram Negative Phyla

•Proteobacteria

•Spirochete

•CFB group

•Planctomycetes

•Phototrophic bacteria

gram positive phyla

Firmicutes and Actinobacteria

Atypical phyla

Tenericutes