cory ni bacteria

Genus:corynebacteria

Members of the genus corynebacteria

GENERAL CHARACTER:

1-Morphology:

-G+ve pleomorphic bacili with club shaped swelling at

one or both ends.

-arranged in chinese letters

(coryneform morphology)include coccoid ,rod,club and filamentous shape.

-Non(spore forming,motile,capsulated).

2-culturally:-

-facultative anaerobic

(37c and PH7.2-7.4)

-grow on blood agar producing hemolysis

3-Biochemically:-

-catalase positive

(except Arcanobacterium pyogenes)

Most common species:-

c.Pseudotuberculosis

(c.ovis)

c.renale

c.Pyogenes

(Arcanobacterium pyogenes)

c.equi

(Rhodococcus equi)

Pathology of corynebacteria:-
Species HostDiseasec.Pseudotuberculosis c.ovisSheep and goat(ovine biotype)Caseous lymphadenitisHorses(equine biotype) ulcerative lymphangitsCattle and buffaloOedematous skin diseasec.Renale groupcattlecystitisSheep and goatUlcerative balanoposthitisArcanobacterium pyogenes(c.pyogenes)cattle-suppurative infections in different tissues-summer mastitisRhodococcus equi (c.equi)Foals and horses-suppurative pneumonia and pulmonary abscessation)

Pathogenicity of corynebacteria:-

c.Pseudotuberculosis

1-Morphology:-

-G+ve bacili.

-chinese letters.

-Non motile.

-Non spore forming.

-Non capsulated.

2-culture characteristics:

-Facultative anaerobic

(with optimum temp is 37c and PH is 7.2-7.5)

**Media for isolation**

-Blood agar beta hemolysis

-coloies are small whitish.

3-Biochemical reactions:-

-catalase positive.

-Ferment glucose and maltose.

-Have 2 types:

Ovine biotype is (nitrate reduction-negative)

Infect ovine,caprine

Equine biotype is(nitrate reduction-positive)

Infect equine,bovine

Virulence factors:

1-cell wall

2-Exotoxins:

-phospholipase D(PLD)

Membrane active cytotoxic toxin

-Serine protease

4-Disease produced by c.ovis:
biotypespeciesdiseaseEquine biotypeHorseUlcerative lymphangitiscattleOedematous skin diseaseOvine biotypeSheep and goatCaseous lymphadenitis

5-Lab.diagnosis of c.ovis:

Sampling:

Samples collected depends on the clinical condition.

-pus in case of suppurative lesions.

1-Direct microscopic examination of Gram stained smear

(Gram positive pleomorphic bacili)

2-Isolation of bacteria

Culture requirements

facultative anaerobic(37c and PH 7.2-7.4)

Media used for isolation

(blood agar:small whitsh colonies surrounded by narrow zone of beta hemolysis)

3-Identification by:

-Colonial characteristics

-Biochemical reactions.

-Animal inoculation(strauss reaction)

-serodiagnosis

-PCR

6-Treatment:

-carried out by prolonged penicillin therapy

-but antibiotic treat in sheep,goat is ineffective

Corynebacterium renale group

3serotypes:

1-c.renale(type|)

2-c.pilosum(type||)

3-c.cystitidis(type|||)

1-Morphology:



(with optimum temp is 37c and PH is neutral)


-Blood agar non hemolytic

-pigment production is variable:
c.renalePale yellow coloniesc.pilosumYellow coloniesc.cystitidisWhite colonies


-catalase positive.

-strong urease-positive.

-CAMP test positive.

4-Disease produced by c.renale group:
cattleCystitis and pyelonephritissheepUlceratie balanoposthitis

5-Lab.diagnosis of c.renale:

Sample collected is mid-stream urine.

1-Direct microscopic examination of Gram stained smear

(Gram positive pleomorphic bacili)



(blood agar:small non hemolytic colonies after 24 hours)

-pigment production is evident after 48 hours


Hemolysis,pigment production)) -Colonial characteristics


(catalase positive ,strong urease positive)

-serodiagnosis

-PCR

(specific primers)

6-Treatment:

-carried out by prolonged penicillin therapy

Genus:Rhodococcus
R.equi
(c.equi)

1-Morphology:

-G+ve coccobacili.

-Non motile.

-Non spore forming.

-capsulated



(with optimum temp is 37c and PH is 7.2-7.5)


-Blood agar non hemolytic

-colonies are mucoid salmon pink


-catalase-positive.

-ferment glucose and maltose.

-Nitrare reduction-positive.

-Urease-positive.

Variability:-

27 capsular serotype

4-Disease produced by R.equi:-

-Infect young foals producing suppurative pneumonia and pulmonary abscessation.

5-Lab.diagnosis of R.equi:-

Samples collected pus from suppurative lesions.

1-Direct microscopic examination of Gram stained smear.

(Gram positive coccobacili)



blood agar: non hemolytic colonies). )




(catalase positive , urease positive, not ferment sugars)

-serodiagnosis

-PCR

(using specific primers)

6-Treatment:

-preferable combined treatment of erythromycin and rifampicin.

Genus:Arcanobacterium
A.pyogenes

1-Morphology:

-G+ve pleomorphic bacili.

-Non motile.

-Non spore forming.

-Non capsulated.



(with optimum temp is 37c and PH is neutral)

-Fastidious bacteria require enriched media.

-Blood agar beta hemolysis

-Colonies are translucent pin point



-catalase-negative.

-Ferment lactose.

-Liquefy gelatin.

-:virulance factors

1-cell wall.

2-Exotoxin:-

-pyolysin O(PLO)

-(acholestrol dependent cytolysin)

-Neuraminidase(for adhesion)

3-Miscellaneous productus as Dnase.

4-Disease produced by A.pyogenes:-

-Purulent infections of

lung,liver,joints,uterus and udder(summer mastitis)

5-Lab.diagnosis of A.pyogenes:-

-samples collected from(milk,pus or exudate).

1-Direct microscopic examination of Gram stained smear.

(G+ve pleomorphic bacili arranged in Chinese letters)


Culture requirement

(facultative anaerobic,37C and PH=7.2-7.4)

Media used for isolation:-

Blood agar:48hours pin point colonies surrounded by asmall zone of beta hemolytic.




(catalase negative,ferment lactose)

-serodiagnosis

-PCR

Using specific primers

6-Treatment:-

-Drainge of abscess.

-Antimicrobial therapy by pencillin.

Thank you very much
With my best wishes:
By:Aya Mohamed

cory ni bacteria

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