Micro Ch 11


T. pallidum












tick borne

 relapsing fever, Lyme disease







leptospirosis (passed through urine/water). 


parasitic, infect animals & humans


C. jejuni  












H. pylori



Free living








found in soil, water, and plants. survive in hospital equipment, I.V. tubing, dialysis machines, water lines


P.  aeruginosa



serious infections in humans


Gram Negative Bacteria

rods, single or in pairs, fastidious, found in water and equipment which is in contact with soil and/or water mist or vapor (A/C units, cooling towers, hot water lines, humidifiers etc.)

L. pneumophila

Gram Negative Bacteria

is an opportunistic pathogen causing a fatal pneumonia in immunocompromised individuals. Sensitive to tetracyclines


Gram Negative Bacteria

non motile bacilli, capsules formed.

B. pertussis

Gram Negative Bacteria

colonizes nasopharynx and trachea in humans. It is the causative agent of “whooping cough”. Erythromycin sensitive. Vaccine available


Gram Negative Bacteria

aerobic/microaerophillic, diplococci, parasites of human mucous membranes. Penicillin & cephalosporin sensitive.

N. gonorrhea:

Gram Negative Bacteria

 sexually transmitted gonococcal urethritis

N.  meningitidis:

Gram Negative Bacteria

meningococcal meningitis (airborne). Growth in candle jar.


Gram Negative Bacteria

nonmotile coccobacilli, zoonotic (parasites of humans and animals: cattle, goats, pigs, dogs).

B. melitensis

Gram Negative Bacteria

produces infection known as brucellosis (undulant fever).  Acquired from direct contact with animals or contaminated animal products.

B. abortus, B suis, B.  canis.

Gram Negative Bacteria

 Tetracycline & streptomycin sensitive.


Gram Negative Bacteria

Also known as the “enteric bacteria”, inhabit the intestines of humans and animals, many are motile, most ferment glucose, posses pili (fimbrae), may interchange plasmids, posses endotoxins. This group includes commensals, opportunistic pathogens, and primary pathogens

Escherichia:  common inhabitant of intestines,

E. coli

Gram Negative Bacteria

used as a research tool and indicator organism for presence of fecal contamination in food and water. Ferment glucose, lactose, sucrose, some strains may cause urinary tract infections and gastroenteritis. Often the main causative agent of opportunistic/nosocomial infections. Tetracycline/erythromycin /ampicillin sensitive.

Gram Negative Bacteria

 opportunistic pathogen, produces red colony pigments, frequently associated with nosocomial infections. May cause urinary and serious respiratory infections in weakened hosts.  May colonize catheters, saline solutions, and other similar objects. Not sensitive to ampicillin


Gram Negative Bacteria

produces distinct capsules and mucoid colonies. Frequent opportunistic nosocomial pathogen, causes pneumonias and septicemias which may be potentially fatal.


Gram Negative Bacteria

highly motile by peritrichous flagella, form a “swarming” colony on agar media. Frequent cause of opportunistic and nosocomial urinary, wound, and respiratory infections.


Gram Negative Bacteria

produce capsules, mucoid colonies, are distinguished from Klebsiella sps. by various culture/biochemical tests. Cause nosocomial/opportunistic urinary and respiratory infections.


Gram Negative Bacteria

primary pathogens, cause gastroenteritis, salmonellosis, typhoid fever. Incapable of lactose fermentation, produce hydrogen sulfide. Many species exist, (over 2000 varieties called serovars, I.D. by antibody testing).

  1. S. typhi
  2. S. dublin
  3. S. arizonae

Gram Negative Bacteria

all important pathogens. Some strains are able to colonize hosts and produce carrier states (e.g. Typhoid Mary).  Transmitted by fecal contamination of food and water; flies, raw milk, meats, and poultry (+ eggs). Ampicillin / Chloramphenicol / Trimethoprim sensitive. [Destroyed by boiling or cooking at temperatures above 700C (160 0F).]

Shigella: similar to Salmonella in non‑utilization of lactose. Pathogens include:

  1. S. sonnei
  2. S.  flexneri
  3. S.  dysenteriae.

Gram Negative Bacteria

Causative agents of shigellosis (bacillary dysentery).  Transmitted by same routes as Salmonella sps. Antibiotic sensitivity = [same as above].

Yersinia: Pathogens include:

  1. Y.  pestis
  2. Y. enterocolita

Gram Negative Bacteria

  1. (flea borne bubonic plague and airborne pneumonic plague),
  2. (yersiniosis gastroenteritis transmitted by meat and milk).

Streptomycin/tetracycline sensitive.


Gram Negative Bacteria

Comma shaped bacilli, free living in bodies of water, motile by monotrichous flagella.

  1. V. cholerae
  2. V. parahaemolyticus
  3. V. vulnificans

Gram Negative Bacteria

  1. the causative agent of cholera (transmitted by contaminated food/water).
  2. cause gastroenteritis – food intoxications acquired by eating raw or undercooked shellfish.
  3. cause gastroenteritis – food intoxications acquired by eating raw or undercooked shellfish.


Gram Negative Bacteria

rod shaped, parasitize animals and humans. pathogens of cattle, fowl, cats and dogs.

Hemophilus: H. influenzae





Gram Negative Bacteria


may inhabit nasopharynx, vagina, and intestines in humans. Produces meningitis, otitis, bronchitis, pneumonias. Requires hemolyzed blood in culture medium for growth. Rifampin sensitive. Vaccine available (Hib).


Gram Negative Bacteria


G. vaginalis

Gram Negative Bacteria

is the cause of the most common vaginitis infections.


Gram Negative Bacteria

 species responsible for serious infections following surgery, puncture wounds, and animal & human bites. Anaerobic organisms found in intestines and mouths of humans and animals.




Gram Negative Bacteria

primarily arthropod borne (fleas, lice & ticks), multiply in bloodstream and cause high fevers, rashes, and collapse.  Obligate intracellular parasites, non‑motile, pleomorphic bacteria. 

  1. R.  prowazekii & R. typhi
  2. R. rickettsii
  3. Ehrlichia chafeensis

Gram Negative Bacteria

  1. cause typhus
  2. causes “Rocky mountain spotted fever”
  3. causes Human granulocytic ehrlichiosis, Tetracycline and doxycycline sensitive


Gram Negative Bacteria

Pathogens of humans and birds.

C. trachomatis

Gram Negative Bacteria

 is the leading cause of non‑gonococcal urethritis in humans (sexually transmitted) .

C. psittaci

Gram Negative Bacteria

causes a serious pneumonia in birds (parrot‑fever) which may be contracted by humans handling birds or exposed to bird droppings etc.
Both Chlamydia species are sensitive to tetracyclines, / erythromycin.

Categories: Microbiology