What is the cellular morphology of Corynebacterium?

Corynebacterium diphtheriae is a Gram-positive nonmotile, club-shaped bacillus. Strains growing in tissue, or older cultures in vitro, contain thin spots in their cell walls that allow decolorization during the Gram stain and result in a Gram-variable reaction.

What are the characteristics of Corynebacterium?

The principal features of the genus Corynebacterium were described by Collins and Cummins in 1986. They are gram-positive, catalase-positive, non-spore-forming, non-motile, rod-shaped bacteria that are straight or slightly curved. Metachromatic granules are usually present representing stored phosphate regions.

Is Corynebacterium jeikeium Gram-positive or negative?

C. jeikeium is a pleomorphic gram-positive rod that varies in form from coccobacillary to bacillary; some appear club shaped.

What is the morphology of Corynebacterium diphtheriae?

C. diphtheriae is a pleomorphic, club-shaped, Gram positive bacillus that is catalase positive, non-motile, non-spore forming, and non-acid fast. On Gram stain, the organisms are typically described as having a “picket fence” or “Chinese character” morphology (image 3).

What kind of shape we see if Corynebacterium diphtheria is seen through microscope?

Bacteriology. Corynebacterium diphtheriae is a slender, Gram-positive bacillus, usually with one end being wider, thus giving the often-described club-shaped appearance.

Is bacillus rod-shaped?

Bacillus species are rod-shaped, endospore-forming aerobic or facultatively anaerobic, Gram-positive bacteria; in some species cultures may turn Gram-negative with age.

What is the shape of Corynebacterium diphtheriae?

C. diphtheriae is a pleomorphic, club-shaped, Gram positive bacillus that is catalase positive, non-motile, non-spore forming, and non-acid fast.

Where does Corynebacterium colonize?

EPIDEMIOLOGY. Corynebacterium spp. can be part of the normal skin and upper respiratory tract flora and commonly colonize hospitalized patients.

Where is Corynebacterium jeikeium found?

Only pathogenic for humans, C. jeikeium is found in soil and water and is part of normal human skin flora. The colonization rate increases with hospitalization; it has been reported in hospital personnel and in up to 40% of hospitalized patients, especially on the skin of the perirectal area, groin, and axilla.

What is coryneform bacillus?

Coryneform bacilli, also known as diphtheroids, are Gram-positive, irregular rod-shaped bacteria that encompass a wide range of genera, such as Corynebacterium, Brevibacterium, Dermabacter, Microbacterium, and Cellulomonas.

What shape and arrangement is Corynebacterium diphtheriae?

What does Corynebacterium diphtheriae look like?

Bacteriology. Corynebacterium diphtheriae is a slender Gram-positive bacillus, usually with one end being wider, thus giving the often-described club-shaped appearance. On culture, particularly under suboptimal conditions, characteristic bands or granules appear.

What is the arrangement of Corynebacterium diphtheriae?

They do not form spores or branch as do the actinomycetes, but they have the characteristic of forming irregular, club-shaped or V-shaped arrangements in normal growth. They undergo snapping movements just after cell division, which brings them into characteristic forms resembling Chinese letters or palisades.

What is the shape of Corynebacterium Xerosis?

rod shaped aerobe
Structure and Physiology This bacteria is a Gram positive, rod shaped aerobe.

How do you get Corynebacterium Jeikeium?

Risk factors for C. jeikeium infection include prolonged hospitalization; profound, extended granulocytopenia; multiple or prolonged courses of antibiotic therapy; disruption of mucocutaneous barriers; and presence of a medical device.

Is Corynebacterium Jeikeium catalase-positive?

Description and significance. Corynebacteria are gram positive, catalase-positive, aerobic, mostly non-motile rods. Corynebacterium jeikeium, an opportunistic pathogen, commonly colonizes in the skin, especially in immunocompromised hosts.

Where can coryneform bacteria be found?

Coryneform bacteria (“diphtheroids”) are ubiquitous in nature. They are found on human skin and mucous membranes, on plants, in soil, and in freshwater and saltwater. Humans are the only known reservoir of C. diphtheriae, although a novel strain was isolated from cats in West Virginia.