gram-

consists of: Neisseria, enteric bacteria

in group Proteobacteria (gram-)

cocci

obligate aerobes

some pathogenic: N. gonorrhoea, N. meningitidis

oxidase positive

in group Proteobactera (gram-)

rod-shaped non-sporulating

oxidase negative

facultative aerobes

genetically closely related

simple nutritional requirements (sugar, salt only) and great biosynthetic capabilities

all ferment glucose and produce different products

contains two categories: mixed acid, producing formic, acetic, etc acid (MR+) and butanediol, a distinctive fermentation product (VP+)

MR+ Enteric bacteria (Proteobactera)

In ALL intestines

helpful: consumes O2, and may produce vitamin K

70% identical to Shigella, therefore technically the same species

MR+ Enteric bacteria (Proteobactera)

Usually pathogenic: typhoid, gastroenteritis

Produces:

enterotoxin

endotoxin (LPS structure in outer gram- membrane that triggers immune response),

cytotoxin (in cell wall, inhibits host protein synthesis via Ca+ flow into host cells; also aids in adherence)

10^4+ serotypes (surface antigens O and H)

MR+ Enteric bacteria (Proteobactera)

Pathogenic through food/water: dysentery

70% identical to Escherichia, therefore technically the same species

MR+ Enteric bacteria (Proteobactera)

Flagellated

interesting swarming patterns on flat cultures, due to density-determined movement

pathogenic: UTI (urease+, breaks down urea)

VP+ Enteric bacteria (Proteobactera)

lives in H2O

VP+ Enteric bacteria (Proteobactera)

In soil

Can cause pneumonia, if it gets into lungs

VP+ Enteric bacteria (Proteobactera)

In soil, water, insect gut

naturally pigmented

Gram-negative, non-spore forming

pathogenic: rocky mountain spotted fever transmitted by arthropods: ticks, lice

Obligate intracellular parasites (can only survive in a host; sometimes, the host can only survive with the bacterium)

not a virus: has muramic acid (therefore, cell wall) and both DNA and RNA metabolism

complex nutritional requirements, produced by the host

Gram+ cocci

S. aureus: pathogenic; MRSA is scary, methicillin resistant

S. epidermis: normal skin flora; nonpathogenic

respiratory metabolism; high salt

Forms clumps

Gram+ cocci

respiratory metabolism; salty environment

forms small clumps

Gram+ cocci

in chains

includes lactic acid bacteria (homofermentative or heterofermentative – streptococcus vs lactococcus) CHECK THIS

causes tooth decay, flesh-eating disease (S. pyogenes), strep throat

gram+ rod-shaped

L. delbrueckii (sp?) in yogurt, also makes pickled foods

acid-tolerant

distinguished by spore location in the rods:

central, subterminal, terminal

want these? heat soil to kill everything else, then culture

gram+ rod-shaped spore forming

aerobic or facultatively aerobic

lives in soil

B. thuringiensis has easy to see crystal in its spore – add this to crops to infect your pests...

Bt corn has the toxin gene from this

gram+ spore forming

gram+ but different – don't gram stain, instead acid-fast stain (Ziehl-Nelson stain, phenol, heat) ends up red; counterstain: methylene blue

mycolic acids coat the cell wall

M. tuberculosis causes TB. Duh.

colonies are tubercles

M. avium is in birds

different, not with gram+ or gram-

important pathogens

3 species: C. psithaci (birds), C. trachomatis (blindness + STI), C. pneumoniae

extracellular form and intracellular form:

look like viruses but aren't

extracellular: elementary body – dispersal agent, similar to spore – drying-resistant, may not be metabolically active

intracellular: reticulate body, reproductive (vegetative form), metabolically active

small genome – 1000 kbp

little metabolic capability on its own

<!-- @page { size: 8.5in 11in; margin: 0.79in } P { margin-bottom: 0.08in } -->

rod-shaped, gram-, no spores

motile (polar flagella), oxidase +

chemoorganotrophic (organic compounds)

can only take in monomers, can't do macromolecules, often xenobiotics – things we put there – pesticides, etc;

aerobic (respiratory, non-fermenting)

lives in soil, decaying plants, animals;

opportunistic pathogens – severe burns, UTIs from P. aeruginosa, often resistant;

<!-- @page { size: 8.5in 11in; margin: 0.79in } P { margin-bottom: 0.08in } -->

gram-, rod-shaped

lack motility

aerobic

pathogenic

purple soil bacterium

Acetic Acid Bacteria

<!-- @page { size: 8.5in 11in; margin: 0.79in } P { margin-bottom: 0.08in } -->

gram-, motile

aerobic, incomplete oxidation of alcohols (hence the name – EtOH --> acetic acid)

we use them for vinegar.

Acetobacter

Gluconobacter – sorbitol --> sorbose, important for vitamin c;