Corynebacterium, Test 2

-aerobic facultative anaerobic gram Positive rods

-coryneform

-does not stain acid fast

-in cell wall

-high energy phosphates

-stained by methylene blue

-humans are only reservoir

-transmitted by airborne droplets or skin contact

-organisms in upper respiratory tract

- A-B toxin

- encoded by tox gene

- encoded by lysogenic phage

-cleaves leader sequence while secretion and cleaves A and B subunits

-Diphtheria toxin binds to heparin-binding epidermal growth factor

-toxin translocate A subunit to cytosol where it ADP-ribosylates elongation factor-2 (prevents protein synthesis)

-Toxin targets oropharyngeal mucosa, heart and nerve cells

-Malaise, exudative pharyngitis and low-grade fever

-dirty white pseudo membrane with dead cells, bacteria and fibrin

-Myocarditis - arrhythmia and death

- Neurotoxicity - peripheral neuritis

-diphtheria antitoxin

-Penicillin to terminate toxin