- Erysipelothrix rhusiopathiae. Erysipelothrix rhusiopathiaecauses erysi-
peloid, which is red, swollen and painful lesions, frequently seen in fisher-
men and meat handlers.
Irregular Nonsporing Gram-Positive Rods
These bacteria are irregular, non-sporing rods. Although this group of bacteria
are generally rod-shaped, their shape can vary (pleomorphic). Some resemble a
club while others are long, threadlike cylinders. There are three genera within
this section. These are:- Corynebacteria. Corynebacteria are club-shaped and receive nutrients from
dead or decaying organic material (saprophytes). Corynebacteria inhabit
airy soil and water and cause diphtheria. Corynebacteria diphtheriae is the
organism which causes diphtheria. - Propionibacterium. Propionibacterium infects wounds and causes abscesses.
An example would be Propionibacterium acnes. - Actinomycetales. Actinomycetales is a long, threadlike cylinder (filament)
that inhibits soil and some provide nitrogen to plants. The species
Actinomycetale israelii, which causes actinomycosis, which destroys tis-
sues in the jaw, head, neck, and lungs. Actinomycetales was originally
classified as a fungus because of its shape.
Mycobacteria
Mycobacteria require oxygen (aerobic) and are acid-fast organisms that remain
red while most are blue. Large amounts of lipids in the Mycobacteria’s cell enve-
lope, resists basic dyes. Myco, which means “fungus-like” is how this organism
got its name.- Mycobacterium tuberculosis. Mycobacterium tuberculosiscauses tuberculosis.
- Mycobacterium leprae. Mycobacterium leprae, also known as M. leprae,
causes Hansen’s disease (leprosy). - Mycobacterium bovis. Mycobacterium bovis, also known as M. bovis,
causes tuberculosis in cattle and can be transmitted to humans.
(^164) CHAPTER 10 The Prokaryotes