CLOSE
WEBSITE OF THE STATE OF SOUTH DAKOTA DEPARTMENT OF HEALTH
Doneen Hollingsworth, Secretary of Health

Yersinia pestis — Colony Characteristics

 

Sheep blood agar

Growth at 24 hours is tiny, almost invisible, shiny gray, translucent “spots.” At 48 to 72 hours, colonies are 1 to 2 mm irregular, gray-white to slightly yellow in color, and have a raised, irregular, “fried egg” appearance, which become prominent as the culture ages.

Nonhemolytic

24 hour growth

MacConkey

Clear, lactose negative colonies

 
Growth on chocolate agar  
Brain Heart Infusion Broth  
Growth is faster at 25 to 28 degrees C than at 37 degrees C. At 25 degrees C growth is suspended flocculent or crumbly clumps, visible at the sides and bottom of the tube with the rest of the media remaining clear. growth in infusion broth
Share via: