Overview of Bacteria Taxonomy and Classification

Cell types

Prokaryotic and eukaryotic

Nutritional requirements

Photosynthetic / nonphotosynthetic

Prokarotae

Prokaryotic organisms - Bacteria

Protista

Eukaryotic, unicellular - amoeba

Fungi

Eukaryotic - yeasts and molds

Plants

All plants - conifers, flowering plants

Animals

All animals, insects, worms, vertebrates

Taxonomy

Science of classification

Robert Whittaker

5 kingdom system

Cellular organization

Unicellular or multicellular

Domains

Based on the ribosomal RNA sequence

Bacteria

Normal flora and pathogens

Peptidoglycan cell wall

Characteristic of Bacteria

Archaea

Prokaryotic, unusual organisms

Extreme environments

Hot springs, dead sea, salt lakes - Pseudomurein

Eukarya

Protista, fungi, plant, animal

Halophiles

Need high concentration of salt - halobacterium

Thermophiles

Sulfolobus; Lives in sulfure rich hot springs 70 Degrees Celsius, pH2

Methanogens

Methanobacterium; Lives in the swamps - breaks down organic matter to make methane

Bergey's manual of systematic bacteriology

Classification scheme evolutionary relationship among bacteria

Species

Organisms with similar characteristics

Strain (Subspecies)

Organisms within the species with slightly different characteristics

E.coli O157:H7

Cattle; Transmitted in undercooked hamburgers; Bloody diarrhea (dysentery)

Bergey's manual of determinative bacteriology

Identification scheme for bacteria based on cell shape, gram reaction, biochemical testing

Serology

Antigen and antibody reactions in vitro

Antigen

Foreign substance, non self - these are bacteria

Antibodies

Proteins that bind to the antigen that stimulated their production and cause the antigen to agglutinate

Slide agglutination test

Test to determine if unknowns are salmonella using agglutination

Rickettsias

Gram negative coccobacillus, Obligate intracellular parasites, Transmitted by insects such as ticks

Rickettsia rickettsii

Rocky mountain spotted fever, transmitted by ticks, rash - palms and soles

Caulobacter

Aquatic environments, has a stalk, attaches to algae and absorbs nutrients

Rhizobium

Roots of plants, beans, and peas; Convert nitrogen gas to ammonium ions

Neisseria gonorrhoeae

Gonorrhea is an STD; Gram negative diplococci; Uses fimbriae to attach itself to the mucus membrane

Bordetella pertussis

Gram negative coccobacillus, whooping cough; Grows on cilia lining the trachea

Thiobacillus

Chemoautotroph; gets energy from hydrogen sulfide; Found in soil; Gram negative, rod shaped

Pseudomonas aeruginosa

Gram negative rod; Opportunist; Water soluble pigment (Blue-green); Burn and wound infections

Escherichia coli

Gram negative bacilli; Normal flora of the intestinal tract; Opportunist; Strain o157:H7 is a pathogen among cattle

Salmonella typhi

Gram negative rod, typhoid fever, found in humans; Carriers are humans within the gallblader

Salmonella enteritidis

Salmonellosis: Poultry and cattle; Undercooked, contaminated food

Klebsiella pneumoniae

Normal flora

Proteus vulgaris

Opportunist

Enterobacter

Opportunist

Serratia marcescens

Soil

Endotoxin

Lipid A

Yersinia pestis

Gram negative rod, The black plague; Spreads from fleas on rats

Vibrio cholerae

Gram negative, bent rod, single flagellum; Produces a toxin 'Cholera'

Chromatium

Gram negative rod found in lakes and ponds; Photosynthetic, uses hydrogen sulfide instead of water

Bdellovibrio

Gram negative bend rod; Pathogenic to E.coli

Desulfovibrio

Sediments of lakes and ponds; Anaerobic respiration

Cyanobacteria

Gram negative and carries on photosynthesis; Found in aquatic environments

Chlamydia

Gram negative cocci, Obligate intracellular parasite

Chlamydia trachomatis 1st Strain

Sexual contact, most common STD, Urethritis

Chlamydia trachomatis 2nd strain

Common in the tropics, southwestern USA; Direct contact, flies, and towels can transmit

Chlamydia trachomatis 3rd strain

Lymphogranuloma venereum STD; Grows in the lymphatic system

Spirochetes

Spiral shaped, axial filaments

Treponema pallidum

Causes syphilis; STD, site of inoculation becomes an ulcer

Borrelia burgdorferi

Lyme disease: Transmitted by ticks from mice

Leptospira interrogans

Leptospirosis - Hooked ends; Infected or carrier dogs excrete urine

Bacteroides

Obligate anaerobe Gram negative rod; Normal flora of our intestinal tract and oral cavity

Mycoplasma pneumoniae

No cell wall, Pleomorphic; Causes walking pneumonia

Clostridum

Gram positive obligate anaerobe; Endospores found in soil

Clostridium tetani

Infects deep puncture wounds; Produces a neurotoxin: spastic paralysis

Clostridium botulinum

Improperly canned food; Neurotoxin causes flaccid paralysis

Clostridium perfringens

Gas Gangrene; Ferments carbohydrates and releases gas

Bacillus anthracis

Causes septicemia; Cutaneous anthrax - cuts and breaks in the skin

Lactobacillus

Gram positive rod, Aerotolerant; Performs fermentation

Staphylococcus aureus

Gram positive, cocci; Causes food poisoning

Streptococcus pyogenes

Gram positive cocci chains; Causes Strep throat and Scarlet Fever

Mycobacterium tuberculosis

Acid Fast, Rod Shaped; Causes TB

Mycobacterium leprae

Causes Leprosy; Grows on face, fingers, toes

Streptomyces

Beneficial bacteria; Most antibiotics used to treat infections are from Streptomyces