Ultrastructure of Nocardia Cell Growth and Development on Defined and Complex Agar Media

Abstract

The cell growth of Nocardia strain 721-A on Brain Heart Infusion Agar (BHIA), nutrient agar, and chemically defined agar media was studied by light and electron microscopy. Light microscopy revealed a change in cell morphology induced by growth on BHIA. Electron microscopy demonstrated a concurrent change in intracellular complexity. On BHIA, the cells became bulbous and developed irregularly branched filaments which fragmented by multiple and random septation. These fragments appeared to undergo a secondary stage of development similar to that described for Arthrobacter . Cells grown on defined or nutrient agar did not become bulbous and lacked the unusual complexity found in cells grown on BHIA. Intracytoplasmic membranes were altered by the nutritional state of the cell and changed during cell development.

Nocardiain naturally acquired and experimental infections in animals

“…No attention was given to standardizing either the type of media used, the way the organisms were grown, or the specific culture age or stage of growth of each strain; often the inoculum was suspended in some adjuvant such as mineral oil (Bach, Gold & Finland, 1973;Destombes et al 1961;Drake & Henrici, 1943;Folb, Jaffe & Altman, 1976;Gonalez-Ochoa, 1962Gonzalez-Ochoa & Sandoval-Cuellar, 1976;Krick & Remmington, 1975;Kurup et al 1970;Kurup & Sandhu, 1965;Macotella-Ruiz & Mariat, 1963;Mason & Hathaway, 1969;Mishra et al 1973;Mohapatra & Pine, 1963;Runyon, 1951;Smith Hayward, 1971;Uesaka et al 1971;Zlotnik & Buckley, 1980). It has been clearly established that all strains of Nocardia that have been studied exhibit varying morphology, ultrastructure, and cell wall composition dependent upon the specific phase of the growth cycle, and the chemical composition and complexity of the growth media (Adams 1966;Beadles, Land & Knezeck, 1980;Beaman, 1975Beaman, , 1976Beaman, Bourgeois & Moring, 1981;Beaman & Maslan, 1978;Beaman et al 1983;Beaman, Serrano & Serrano, 1978;Beaman & Shankel, 1969;Dipersio & Deal, 1974;Farshtchi & McClung, 1967;Kinbara, 1968;Vistica & Beaman, 1983;Watanabe, Kumagaya & Murooka, 1963). Therefore each individual strain of Nocardia will have its own unique growth curve; some growing faster and others growing slower, under the same experimental conditions.…”

Structural and biochemical alterations of Nocardia asteroides cell walls during its growth cycle

“…The frozen specimens were transferred to liquid nitrogen for temporary storage. Samples, placed in a Balzers freeze-etch apparatus, were cleaved, etched, and shadowed as previously described (9). The replicas were cleaned in hypochlorite or concentrated sulfuric acid, mounted on cooper grids, and examined under the electron microscope as described above.…”

“…The nocardiae characteristically undergo morphological change during their growth cycle. Beaman and Shankel reported that there were considerable structural modifications occurring in cells of Nocardia rubra 721-A during growth (9). Further, it was observed that cell wall structure and intracytoplasmic membrane organization was affected most by culture age and media composition (9).…”

“…Beaman and Shankel reported that there were considerable structural modifications occurring in cells of Nocardia rubra 721-A during growth (9). Further, it was observed that cell wall structure and intracytoplasmic membrane organization was affected most by culture age and media composition (9). Based on these observations it would be reasonable to assume that significant chemical changes occurred in the nocardial cell, particularly the cell wall, during the various stages of nocardial growth.…”

Isolation and properties of mesosomal membrane fractions from Micrococcus lysodeikticus

“…More recently the internal structure of peripheral and mesosomal membranes has been revealed by using the freeze-etching technique on whole cells. In some bacteria examined by this technique, the intracellular membranes have appeared smooth (Nanninga, 1968;Beaman & Shankel, 1969;Wildermuth, 1971), whereas the peripheral membrane invariably appeared particle-studded. In other instances both mesosomal and peripheral membranes appeared particle-studded (Fiil & Branton, 1969;Sleytr, 1970;Sleytr & Kocur, 1971;Sleytr & Krebs, 1971) and, in some reports, mesosomes with either smooth or particle-studded fracture faces were observed in the same organism (Remsen, 1968;Holt & Leadbetter, 1969).…”