Bacteria

Microbiologists broadly classify bacteria according to their shape: spherical, rod-shaped, and spiral-shaped. Pleomorphic bacteria can assume a variety of shapes. Bacteria may be further classified according to whether they require oxygen (aerobic or anaerobic) and how they react to a test with Grams stain. Bacteria in which alcohol washes away Grams stain are called gram-negative, while bacteria in which alcohol causes the bacterias walls to absorb the stain are called gram-positive.

TYPE ----- CHARACTERISTICS

Acetic acid

Rod-shaped, gram-negative, aerobic; highly tolerant of acidic conditions; generate organic acids

Actinomycete

Rod-shaped or filamentous, gram-positive, aerobic; common in soils; essential to growth of many plants; source of much of original antibiotic production in pharmaceutical industry

Coccoid

Spherical, sometimes in clusters or strings, gram-positive, aerobic and anaerobic; resistant to drying and high-salt conditions; Staphylococcus species common on human skin, certain strains associated with toxic shock syndrome

Coryneform

Rod-shaped, form club or V shapes, gram-positive, aerobic; found in wide variety of habitats, particularly soils; highly resistant to drying; include Arthrobacter, among most common forms of life on earth

Endospore-

forming

Usually rod-shaped, can be gram-positive or gram-negative; have highly adaptable, heat-resistant spores that can go dormant for long periods, possibly thousands of years; include Clostridium (anaerobic) and Bacillus (aerobic)

Enteric

Rod-shaped, gram-negative, aerobic but can live in certain anaerobic conditions; produce nitrite from nitrate, acids from glucose; include Escherichia coli, Salmonella (over 1000 types), and Shigella

Gliding

Rod-shaped, gram-negative, mostly aerobic; glide on secreted slimy substances; form colonies, frequently with complex fruiting structures

Lactic acid

Gram-positive, anaerobic; produce lactic acid through fermentation; include Lactobacillus, essential in dairy product formation, and Streptococcus, common in humans

Mycobacterium

Pleomorphic, spherical or rod-shaped, frequently branching, no gram stain, aerobic; commonly form yellow pigments; include Mycobacterium tuberculosis, cause of tuberculosis

Mycoplasma

Spherical, commonly forming branching chains, no gram stain, aerobic but can live in certain anaerobic conditions; without cell walls yet structurally resistant to lysis; among smallest of bacteria; named for superficial resemblance to fungal hyphae (myco- means "fungus")

Nitrogen-fixing

Rod-shaped, gram-negative, aerobic; convert atmospheric nitrogen gas to ammonium in soil; include Azotobacter, a common genus

Propionic acid

Rod-shaped, pleomorphic, gram-positive, anaerobic; ferment lactic acid; fermentation produces holes in Swiss cheese from the production of carbon dioxide

Pseudomonad

Rod-shaped (straight or curved) with polar flagella, gram-negative, aerobic; can use up to 100 different compounds for carbon and energy

Rickettsia

Spherical or rod-shaped, gram-negative, aerobic; cause Rocky Mountain spotted fever and typhus; closely related to Agrobacterium, a common gall-causing plant bacterium

Sheathed

Filamentous, gram-negative, aerobic; "swarmer" (colonizing) cells form and break out of a sheath; sometimes coated with metals from environment

Spirillum

Spiral-shaped, gram-negative, aerobic; include Bdellovibrio, predatory on other bacteria

Spirochete

Spiral-shaped, gram-negative, mostly anaerobic; common in moist environments, from mammalian gums to coastal mudflats; complex internal structures convey rapid movement; include Treponemapallidum, cause of syphilis

Sulfate- and

Sulfur-reducing

Commonly rod-shaped, mostly gram-negative, anaerobic; include Desulfovibrio, ecologically important in marshes

Sulfur- and

iron-oxidizing

Commonly rod-shaped, frequently with polar flagella, gram-negative, mostly anaerobic; most live in neutral (nonacidic) environment

Vibrio

Rod- or comma-shaped, gram-negative, aerobic; commonly with a single flagellum; include Vibrio choler, cause of cholera, and luminescent forms symbiotic with deep-water fishes and squids

FAMILY ----- VIRUS ----- DISEASE

Adenovirus

Common cold

Bunyavirus

HantaanLa CrosseSin Nombre

Kidney failureEncephalitis (brain infection)Lung syndrome

Calicivirus

Norwalk

Gastroenteritis (diarrha, vomiting)

Coronavirus

Corona

Common cold

Filovirus

EbolaMarburg

Hemorrhagic feverHemorrhagic fever

Flavivirus

Hepatitis C (non-A, non-B)Yellow fever

HepatitisHepatitis, hemorrhage

Hepadnavirus

Hepatitis B virus (HBV)

Hepatitis, liver carcinoma

Herpesvirus

CytomegalovirusEpstein-Barr virus (EBV)Herpes simplex type 1Herpes simplex type 2Human herpesvirus 8 (HHV8)Varicella-zoster

Birth defectsMononucleosis, nasopharyngeal carcinomaCold soresGenital lesionsKaposi's sarcomaChicken pox, shingles

Orthomyxovirus

Influenza types A and B

Flu

Papovavirus

Human papillomavirus (HPV)

Warts, cervical carcinoma

Picornavirus

Coxsackie virusEchovirusHepatitis APoliovirusRhinovirus

Myocarditis (heart muscle infection)MeningitisInfectious hepatitisPoliomyelitisCommon cold

Paramyxovirus

MeaslesMumpsParainfluenza

MeaslesMumpsCommon cold, ear infections

Parvovirus

B19

Fifth disease, chronic anemia

Poxvirus

Orthopoxvirus

Smallpox (eradicated)

Reovirus

Rotavirus

Diarrhea

Retrovirus

Human immunodeficiency virus (HIV)Human T-cell leukemia virus (HTLV-I)

Acquired immunodeficiency syndrome (AIDS)Adult T-cell leukemia, lymphoma, neurologic disease

Rhabdovirus

Rabies

Rabies

Togavirus

Eastern equine encephalomyelitisRubella

EncephalitisRubella, birth defects