BACTE LEC AEROBIC GRAM POS BACILLI

bacillus

• gram pos that forms spore aerobically

• catalase positive

• motile (peritrichous flagella)

• anthracis, cereus

bacillus anthracis

• bamboo-like appearance on microscope

• encapsulated

• largest and most pathogenic bacillus sp

• 35-37 deg celsius

• forms round irregularly shape, grayish, opaque colored colonies

polymyxin lysozyme edta thallous acetate

• is the most common selective medium for b. anthracis

anthrax

• sources: cattle, goats, hairs, and other herbivorous animals

• animals acquire the infection through ingestion of spores present on the soil

• can be cutaneous, pulmonary, gi

cutaneous anthrax

• most common but less severe form

• occurs if the organism enters the body through a skin cut

• develop into necrotic area

• may invade lymph nodes and blood if left untreated

pulmonary anthrax

• woolsosters’ disease

• results in the inhalation of spores during sorting of animal hair or hides

• less common but with high mortality rate

gastrointestinal anthrax

• most severe form

• ingestion of the bacilli or spores from the contaminated food

bacillus cereus

• important cause of food poisoning

• generally motile

• commonly isolated from soil, vegetables and some foods like milk, cereals, meat products, and fried rice

• non capsulated

• spores: central to subterminal

food poisoning

• associated with vomiting from the release of emetic toxin 6 hours after ingestion of the organism

• can recover without intervention

• spores are not killed during cooking and germinate when left untreated

• diarrheal effects are seen within one-half after ingestion of the contaminated food

bacillus subtilis

• known also as the hay bacillus or grass bacillus

• gram pos, catalase pos, motile, grown on 6.5% nacl

• found in soil and gi tract

• bacteremia, endocarditis, pneumonia, and septicemia

listeria monocytogenes

• gram pos, small rod shape bacteria

• non motile facultative anaerobe

• found in soil, water, sewage, and decaying vegetation and feces

• most significant specie (listeria)

listeriosis

• through contaminated food

• cause severe illness, including severe sepsis, meningitis, or encephaltis

• highest risk are newborn, elderly, people with weakened immune systems and pregnant women

tumbling motility

• motility of listeria

ocular test of anton

• virulence test of listeria

• inoculation of the organism on the eye of the rabbit, if there is conjunctivitis it indicates positive result

corynebacterium

• slender, pleomorphic gram pos bacilli

• facultative anaerobes

• known as klebs loeffler bacillus

• non spore formers

• catalase and oxidase positive

corynebacterium diphtheriae

• most virulent specie (corynebacterium)

• non motile

• urease neg

• catalase pos

• glucose fermenter

• produces powerful exotoxin, attacks the mucous membrane of the respiratory tract which causes inflammation and respiratory obstruction

diphtheria

• affects the mucous membranes of the nose and throat

• can damage heart, kidneys, and nervous system

• bulls neck (enlarged lymph nodes)

schick’s test

• susceptibility test for diphtheria

• arm + diphtheria toxin = erythema

erysipelothrix rhusiopathiae

• gram pos but decolorizes easily

• alpha and non hemolytic on bap

• catalase neg

• h2s pos

• agent of erysipeloid

erysipeloid

• a minor skin injury may facilitate the penetration of e rhusiopathiae after contact with infected material, after an incubation of 1 to 4 days the local lesion develops, spontaneous recovery occurs in 2-3 weeks

lactobacillus acidophilus

• normal flora of the mouth, git, and vaginal canal

• non pathogenic and less clinically significant

• helps maintain the normal homeostatic environment by producing lactic acid (pH: 3-4)

• gram pos

• catalase neg

• non motile

tomato juice agar

• culture media for l. acidophilus

rothia

• normal flora of the human mouth

• rare caused of abscesses and endocarditis

kurthia

• found in soil

• opportunistic pathogen

• motile through peritrichous flagella

• obligate aerobe

• catalase pos

• oxidase neg

nocardia

• partially acid fast bacilli

• retain carbolfuschin after decolorization with mild acid

• grow in saboroud dextrose agar

streptomyces

• largest genus of the family actinomycetes

• soil and decaying vegetation

• noted for their distinct earthy odor that results from production of a volatile metabolite, geosmin

• assoc with mycetoma

• known as madura foot