Bacteria morphology

The possibility that pulmonary membranes are a primary site of ozone toxicity is suggested by a number of lines of evidence, most of which are indirect. These include observations that the membrane is the major site of ozone toxicity in plants and bacteria morphologic evidence of pulmonary membrane damage after ozone exposure in a number of studies and in vitro experiments with human red cells and artificial lipid membranes. 

Budding bacteria morphologies actively concentrating manganese. 

Resistance to antimicrobial agents is of concern as it is well known that bacterial resistance to antibiotics can develop. Many bacteria already derive some nonspecific resistance to biocides through morphological features such as thek cell wall. Bacterial populations present as part of a biofilm have achieved additional resistance owkig to the more complex and thicker nature of the biofilm. A system contaminated with a biofilm population can requke several orders of magnitude more chlorine to achieve control than unassociated bacteria of the same species. A second type of resistance is attributed to chemical deactivation of the biocide. This deactivation resistance to the strong oxidising biocides probably will not occur (27). 

Virtually all metallurgies can be attacked by corrosive bacteria. Cases of titanium corrosion are, however, rare. Copper alloys are not immune to bacterial attack however, corrosion morphologies on copper alloys are not well defined. Tubercles on carbon steel and common cast irons sometimes contain sulfate-reducing and acid-producing bacteria. Potentially corrosive anaerobic bacteria are often present beneath... 

Corrosion morphologies. Sulfate-reducing bacteria frequently cause intense localized attack (Figs. 6.2 through 6.7). Discrete hemispherical depressions form on most alloys, including stainless steels, aluminum. Carpenter 20, and carbon steels. Few cases occur on titanium. Copper alloy attack is not well defined. 

The earliest morphological change in the sebaceous follicle is an abnormal follicular epithelial differentiation, which results in ductal hypercornification. Cornified cells in the upper section of the follicular canal become abnormally adherent. Comedones represent the retention of hyperproliferating ductal keratinoc-ytes in the duct. Several factors have been implicated in the induction of hyperproliferation sebaceous lipid composition, androgens, local cytokine production (IL-i, EGF) and bacteria (P. acnes). 

Tlie morphology of some bacteria, especially those that form spores, is distinctive enough under the light microscope to have value for identification. This means that differential staining techniques, such as the Gram stain or acid-fast stain, and fluorescence microscopy may help to determine the iden-... 

Robbins, E. I. Bacteria and Archaea in acidic environments and a key to morphological identification. Hydrobiologia 2000,433, 61-89. 

These changes in morphology induced by chemical substances are usually temporary, since reversion to normal form occurs promptly when the filamentous bacteria are subcultured in the absence of the inhibitory agents. Irradiation, on the other band, may give rise to a temporary or permanent induction of filamentous cells. 

The shape of an organism may also vary depending upon certain environmental factors, such as temperature of incubation, age of the culture, concentration of the substrate, and composition of the medium. Bacteria usually exhibit their characteristic morphology in young cultures and on media possessing favorable conditions for growth. 

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