Characterization of a Propionic Acid Producing Actinomycete, Actinomyces propionicus, Sp.nov.

Abstract

SIJMRlARYAn anaerobic actinomycete isolated from the lachrymal duct of a case of human lachrymal canaliculitis is described. Although the organism was described previously as Actinomyces israelii, more recent observations show it diir'ers significantly from members of this genus in metabolism, physiology and cell-wall composition. The organism is similar to the Actinomyces in its production of true branching mycelial elements in vivo and iiz vitro, catalase negativity, pathogenicity for experimental animals, and amino acid cell-wall composition. It is similar to the propionic acid bacteria in its fermentation of glucose to propionate, acetate, and CO,, its morphological variation, formation of a dull orange colour, and the presence of diaminopimelic acid in its cell wall. Other characteristics such as the formation of DL-lactic acid, absence of a CO, requirement either anaerobically or aerobically, inability to ferment glycerol or lactate, and sugar and amino sugar composition of the cell wall also serve to differentiate this organism from other strains of Actinomyces and from Propionibacterium. In view of these observations the organism is reclassified and named A. propionicus, sp.nov. The possible phylogenetic relation of A . propionicus to certain other branching filamentous organisms is discussed.

Numerical Taxonomy and Laboratory Identification of Actinomyces and Arachnia and some Related Bacteria

“…The genus Arachnia was set up by Pine & Georg (1969) to accommodate propionateproducing bacteria with diaminopimelic acid in their wall, previously classified as Actinomyces propionicus (Pine & Hardin, 1959;Buchanan & Pine, 1962). The phenotypic data presented here indicate that the Arachnia strains form a recognizable taxon, phenetically distinct from the other generic phena.…”

Path of Glucose Breakdown and Cell Yields of a Facultative Anaerobe, Actinomyces naeslundii

“…McDonald, Cheldelin & King, 1960). Extracts of a related organism, Actinomyces propionicus (Buchanan & Pine, 1962), also showed aldolase activity, with a rate about two-thirds that observed in A. naeslundii, thus indicating the Embden-Meyerhof pathway is possibly widespread in this group of organisms. Glucosephosphate isomerase, an enzyme of the Embden-Meyerhof pathway, and phosphate acetyltransferase, which often occurs in anaerobic bacteria (Stadtman, 1955), were also present in A. naeslundii ( Table 2).…”

“…These values are at least twice those reported for most other organisms. However, Gunsalus & Shuster (1961) reported a Y value of 37.5 of Propionibacterium pentosaceum, an organism which in many ways is closely related to the actinomyces species (Stanier & Van Niel, 1941;Buchanan & Pine, 1962). As a result of the high Y values observed with A .…”

“…bovis, ATCC 10049), described previously (Buchanan & Pine, 1963), and Actinomyces propionicus (Buchanan & Pine, 1962) were grown at 37" in the casitone medium of Pine & Watson (1959) or in the casein hydrolysate medium of Pine & Howell (1956). Fermentation products were analysed as described previously (Buchanan & Pine, 1963).…”

Comparative Pathogenicity of Actinomyces Species in Mice

“…naeslundi, A . viscosus and A . odontolyticus as well as Arachnia propionica have been isolated from human actinomycotic lesions (Buchanan and Pine, 1962;Coleman, Georg and Rozzell, 1969;Georg et al, 1972;Mitchell, Hintz and Haselby, 1977). In addition, these other species can induce experimental actinomycosis in certain laboratory animals Georg and Coleman, 1970).…”