Microbial differentiation and changes in susceptibility to antimicrobial agents

Autoimmunity in the Mediation of Granulomatous Amoebic Encephalitis: Implications for Therapy

“…Bacteria grown in Acanthamoeba show resistance to bactericides and biocides; their survival and virulence are enhanced; and they mechanically transport disease-producing agents to various target organs, thus increasing the risk of multiple infections in the affected patients (King, et al, 1988, Barker, et al, 1995, Turner, et al, 2000, Lloyd, et al, 2001, Marciano-Cabral & Cabral, 2003. The amoebae shed waste through vesicles of 2.1 to 6.4 µm diameter, and they can potentially contain pathogenic microbes.…”

Single-Cell Microbiology: Tools, Technologies, and Applications

“…Sources of physiological variation in bacteria include differences in cell volume, cell shape, buoyant density, and nucleoid morphology (152). More pronounced examples of cell cycle-related physiological heterogeneity occur in organisms undergoing processes of differentiation, such as sporulation or the formation of fruiting bodies (237,248). Physiological (and biochemical) heterogeneity may also be driven by microenvironmental factors acting on cells located in different strata within a colony or biofilm (42,55).…”

“…Individual microorganisms, even those in "clonal" populations, may differ widely from each other in terms of their genetic composition, physiology, biochemistry, or behavior (40,66,75,127,208). This variability or heterogeneity has important practical consequences for a number of human interests, including antibiotic and biocide resistance (21,228,237), the productivity and stability of industrial fermentations (184,205,229), the efficacy of food preservatives, (17,223,229), and the potential of pathogens to cause disease (67). Additionally, methods for identification, characterization, and/or physical separation of individual microorganisms are needed for the detection of pathogens and for the identification and selection of strains with beneficial or improved properties (124,224).…”

When is a Vase Solution Biocide not, or not only, Antimicrobial?

“…Moreover, the developmental stage of a microorganism may result in a differential response to a biocidal agent. For instance, fully mature spores of Bacillus subtilis are much less susceptible to biocides than non-sporulating bacteria or vegetative cells (Turner et al, 2000). The differential response of microorganisms to biocides may be ascribed to variations in morphological structure (e.g.…”

“…different types of peptidoglycans in bacterial spores) of the individual microorganism (Maillard, 2002;Turner et al, 2000). To be effective, an antimicrobial treatment must function in all conditions, including across varying vase solution composition (Knee, 2000), and against the prevalent microorganism, such as a specific bacterial species (Turner et al, 2000).…”