### microbacteria:

Resistant bacteria
* Most resistant bacteria can produce substances which destroy the antibiotic.
* are hard to treat and can cause serious problems and even death.
* arise through a process called natural selection.
* become dominant through competitive selection.
* can develop in an individual, hospital or community.
* develop a variety of mechanisms to dodge the antibiotic bullet
  - because of overuse and misuse of antibiotics
  - when antibiotics are used too often or incorrectly
* emerge because of overuse and misuse of antibiotics.
* evolve as a result of using antibiotics.
* gain defense mechanisms by borrowing genetic material from other bacteria.
* multiply when non-resistant bacteria die.
* pose an ever-increasing threat.

Saprophytic bacteria
* Most saprophytic bacteria excrete usable nutrients.
* feed off dead and decaying matter.

Several bacteria
* appear to contain analogous oxidases.
* cause serious problems on fruit plants.
* have their DNA completely sequenced and reported.

Shigella
* are always pathogenic
  - bacteria that cause an intestinal infection
* multiply at room temperature.
* often causes outbreaks in daycare centers.

### microbacteria:

Soil bacteria
* All soil bacteria require for their growth a certain amount of oxygen.
* Most soil bacteria convert nitrate.
* Most soil bacteria play indispensable roles
* Some soil bacteria kill insect larvae
* are also responsible for the medications erythromycin, streptomycin and tetracycline
  - either autotrophic or heterotrophic
  - mostly saprophytes or parasites
  - of special interest because of their many varied activities
  - the natural soil microorganisms that break down soil components into plant food
* breakdown the effluent aerobically, which means with the presence of oxygen.
* can also improve soil structure by enhancing the formation of aggregates.
* convert nitrogen gas to a usable form for plants.
* decompose biodegradable material
  - organic nitrogen forms in soil to the ammonium form
* destroy some of the pollutants.
* encompass a wide range of nutritional types.
* help water to dissolve rock particles in soils.
* is classified under two heads, autotrophic and heterotrophic.

Spiral bacteria
* Most spiral bacteria infect animals.
* Some spiral bacteria cause diseases
  - severe diseases
  - find in stomachs

Spirochaete
* Most spirochaetes are free-living and anaerobic , but there are numerous exceptions.
* are spiral shaped bacetria.

### microbacteria:

Spirochete
* Most spirochetes are anaerobic.
* Some spirochetes can also selectively inhibit the proliferative response of lymphocytes.
* are a spiral-shaped bacteria that infect the body by burrowing in through the skin
  - corkscrew-shaped bacteria that move by undulating
  - long, thin, spiral-shaped bacteria
  - the causitive agents of both syphilis and yaws
  - very difficult to stain
  - well adapted to swim in viscous liquids
* can also live by themselves.
* convert two gases in termite stomachs, hydrogen and carbon dioxide, into acetic acid.
* have an axial filament attached at both ends and within a membrane sheath.
* live in many habitats, including cow stomachs, termite guts and compost heaps.
* play a role in ulcerative gingivitis and periodontitis.

### microbacteria:

Staph bacteria
* are a frequent cause of infection in burns, skin and surgical wounds
  - harmless in most healthy people
  - one of the most common causes of food poisoning
  - widespread and cause mild to severe skin infections in dogs of all ages
* can also become resistant to certain antibiotics
  - cause skin, wound and other infections
* grows well in high salt concentrations and in high sugar concentrations.
* prefer cooked food high in protein.
* produce a toxin in the food as they multiply.

Streptococcus
* kills white blood cells.
* pyogenes A common bacterium that causes strep throat and can also cause tonsillitis.