Bacteria oxygen consumption

Organic matter Accumulation of organic matter Bacteria Primary producers Slowed down decomposition High oxygen consumption High mineralization... 

An important observation made by Larionovi [128] was that TNT, present in waste waters in a concentration of 25-80 mg/1., lowered the oxygen consumption of bacteria by 5-30% possibly because it inhibited their activity. In addition, TNT has been found toxic to some seaweeds and to fish. 

In working with bacteria or zones in the ocean where bacteria dominate the biological community, a different coefficient should be used. In situations where the bacteria are growing and the ETS method of Packard et al. (55) is used to determine the oxygen consumption, a coefficient of 5.0 should be used. This value is based on 49 experiments with five species of marine bacteria (76). In situations where the bacteria are not growing, as in senescence, a coefficient of 0.43 should be used (Table II) (76). Calculations of deep-sea oxygen-consumption rates (68, 76) were made with the assumption that the deep water populations were dominated by bacteria in a senescent phase therefore, the coefficient of 0.43 was used. 

Top the equation R = 1.92 ETS — 0.99, where R is the oxygen-consumption rate, describes the samples taken from the Georges Bank-Gulf of Maine cruise on the R.V. Eastward in July 1980. Bottom the equation R = 1.29 ETS + 4.71 describes the ETS dependence of oxygen consumption of the bacterium, P. perfectomarinus. The differences in the equations may reflect the differences of the analysis of bacterial and phytoplankton ETS. In bacteria the ETS is housed in the cell mall, so crude homogenates must be used. In phytoplankton the ETS is housed in the mitochondria thus, partially purified homogenates free of cell walls and nuclei are used. (Reproduced with permission from Ref. 67 and 75.)... 

Facultative bacteria may provide an environment conducive to the growth of anaerobic bacteria. Although many bacteria isolated in mixed infections are nonpathogenic by themselves, their presence may be essential for the pathogenicity of the bacterial mixture. The role of facultative bacteria in mixed infections can include (1) promotion of an appropriate environment for anaerobic growth through oxygen consumption, (2) production of nutrients necessary for anaerobes, and (3) production of extracellular enzymes that promote tissue invasion by anaerobes. 

The bacteria harvested at the end of 18-h growth were suspended in TBS solution (10 CPU per mL) and then stored over ice for 24 h. The oxygen consumption rates for 10 cells were measured (+ 5.0 mM glucose) with and without 2.0 pM of CCCP in TBS. For ATP measurements, 10 cells in glucose containing TBS were used. 

Licochalcone A and C have been shown to possess activity in vitro against Gram-positive bacteria (Haraguchi et al., 1998). The mechanism of this effect is hypothesized to be inhibition of oxygen consumption and NADH oxidation in susceptible bacterial cells through inhibition of mitochondrial NADH-cytochrome c reductase. 

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