Bacteria, activity of soil

Cooper RE, Hedrick HG. 1976. Activity of soil bacteria on petroleum waste adjacent to an active oil well. Soil Sci 122(6) 331-338. 

The British Non-Ferrous Metals Research Association carried out two series of tests, the results of which have been given by Gilbert and Gilbert and Porter these are summarised in Table 4.12. In the first series tough pitch copper tubes were exposed at seven sites for periods of up to 10 years. The two most corrosive soils were a wet acid peat (pH 4-2) and a moist acid clay (pH 4-6). In these two soils there was no evidence that the rate of corrosion was decreasing with duration of exposure. In the second series phosphorus-deoxidised copper tube and sheet was exposed at five sites for five years. Severe corrosion occurred only in cinders (pH 7 1). In these tests sulphides were found in the corrosion products on some specimens and the presence of sulphate-reducing bacteria at some sites was proved. It is not clear, however, to what extent the activity of these bacteria is a factor accelerating corrosion of copper. 

Tholen A, Brune A. 1999. Localization and in situ activities of homoacetogenic bacteria in the highly compartmentalized hindgut of soil-feeding higher termites (Cubitermes spp.). Appl Environ Microbiol 65 4497-505. 

Biological. In activated sludge, 31.5% of the applied chlorobenzene mineralized to carbon dioxide after 5 d (Freitag et al., 1985). A mixed culture of soil bacteria or a Pseudomonas sp. transformed chlorobenzene to chlorophenol (Ballschiter and Scholz, 1980). Pure microbial cultures isolated from soil hydroxylated chlorobenzene to 2- and 4-chlorophenol (Smith and Rosazza, 1974). Chlorobenzene was statically incubated in the dark at 25 °C with yeast extract and settled domestic wastewater inoculum. At a concentration of 5 mg/L, biodegradation yields at the end of 1 and 2 wk were 89 and 100%, respectively. At a concentration of 10 mg/L, significant... 

Naturally occurring compounds that contain epoxides include periplanone B, the sex pheromone of the female American cockroach, and epothilone B, a novel anticancer drug. The epothilones represent a new group of anticancer drugs first isolated in 1987 from soil bacteria in southern Africa. Because they are active against many taxol-resistant tumors and are readily produced by the fermentation of soil bacteria, they hold great promise for cancer treatment in the future. 

Due to the activity of soil and aquatic bacteria and moulds, organic substances polluting the environment are chemically decomposed, in contrast... 

Fungi, which are active in upland environments, cease to exist in wetland soils. This is primarily due to the absence of oxygen and alteration in soil pH (acid to neutral) under anaerobic conditions. Overall, microbial biomass decreases under saturated soil conditions. The metabolic activities of anaerobic bacteria depend on alternate electron acceptors, such as oxidized forms of nitrogen, iron, manganese, and sulfur. Under wetland soil conditions, rates of many microbially mediated reactions decline, and some reactions may be eliminated and replaced by new ones. New microbial reactions are involved in the reduction of oxidized compounds during respiratory processes, resulting in the production of reduced compounds. 

Many species of plants, including some fungi, bacteria, algae, and higher plants, produce cyanide as a metabolic product. Some species of soil bacteria suppress plant diseases caused by soilborne pathogens by producing metabolites with antibiotic activity. Certain strains of Pseudomonas fluorescens, a soil bacterium, suppress black root rot of tobacco... 

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