UNIQUE GROWTH CHARACTERISTICS

S. pneumoniae

Dome shaped appearing colonies after 24 hrs

Colonies appearing like coin with raised rim

Nail head like after 48 hrs

B. anthracis

Colonies with swirling projections “Medusa head” “Lion Head”

Colonies with beaten egg white consistency

Inverted Pine tree in Gelatin Media

Mycoplasma

Fried egg appearing on BAP

Pseudomonas aeruginosa

Greenish metallic sheen on BAP

Pyocyanin (Blue) & pyoverdin (Green) (+)

Colonies with odor similar to overripe grapes, Corn taco odor

E. coli

Greenish metallic sheen on EMB

H. influenzae

Dew drop appearing colonies (mousiness odor)

M. catarrhalis

Hockey Puck colonies / Movable

Legionella

Colonies with Ground glass appearance

P. stutzeri & B. pseudomallei

Non-fermenter (+) Wrinkled colonies

Eikenella corodens

Pit and corrode with typical bleach like odor

C. difficile

in CCFA = Colonies with horse stable / barn yard odor

in BAP = Fluoresence chartreuse

Genus Proteus

• Colonies with burnt chocolate, Burnt gun powder odor

• Swarming gm (-), oxidase (-)

Chromobacterium violaceum

Violet pigment - violacein

Yersinia pestis

Hammered (very flat) Copper colonies on BAP

Stalactite / flocculent growth on broth

SAFETY PIN APPEARANCE

S. agalactiae

Bull’s eye appearing colonies, Gram positive (mucoid)

Y. enterocolitica

Bull’s eye appearing colonies, Gram negative rod, Oxidase negative

if you use CIN = pink colonies w/ red center

Aeromonas

Bull’s eye appearing colonies, Gram negative rod, Oxidase positive

Bordatella

Mercury droplet like colonies

M. bovis

Water droplet like colonies

A.israelli

Molar tooth appearing

S. moniliformis

Puff balls / fluff balls

Listeria

Umbrella like growth on agar surface

S. aureus

Colonies with odor like an old sock on MSA

M. tuberculosis

Colonies appearing cauliflower like

M. xenopi

Bird’s nest appearing

corn meal

Serratia marcescens & Serratia rubidea

Prodigiosin (+) [Red piment]

Prevotella & Porphyromonas

Brick red fluorescence under UV And black under ordinary light

C. diphtheriae

Gray Black colonies on CTBA

E. rhusiopathiae

Bottle Brush like / Test Tube Brush Like

Y. pestis

B. fragilis

P. multocida

C. granulomatis

Bacterial Growth that shows Safety Pin Appearances: