Obligatory anaerobes

Kawasaki S, Y Watamura, M Ono, T Watanabe, K Takeda, Y Niimura (2005) Adaptive responses to oxygen stress in obligatory anaerobes Clostridium acetobutylicum and Clostridium aminovalericum. Appl Environ Microbiol 71 8442-8450. 

Testing for obligatory anaerobes is performed every 3 months routinely. However, more frequent testing is indicated, especially when the identification of these organisms occurs in sterility testing. 

Lacustrine Pertaining to development in lakes Mesic This term has a very broad meaning. In ecology, it refers to moderate conditions with respect to both temperature and moisture. In soil, specifically in soil taxonomy, mesic is used to represent a soil temperature (mean annual) that falls in the range 8-15° C Mole fraction The ratio of the moles of a substance to the total number of moles in the sample. In the atmosphere this is the same as the volume fraction Non-seasalt (nss) The amount of an element or compound in the bulk aerosol mass that is in excess of its seawater ratio with sodium or chloride. Often applied to sulfate Obligatory anaerobes Organisms restricted to life in anaerobic environments... 

Last but not least, life continues to flourish within the ZnS-coated, deep sea hydrothermal fields, with their inhabitants categorized mostly as Archaea [115,117]. It might be worthwhile to inspect those ZnS-confined communities more closely. Although the ocean waters are saturated by oxygen, the interiors of the chimneys remain anoxic, because of the reduced state of hydrothermal fluids, so that many inhabitants of the vents are obligatory anaerobes [104]. There is a small chance that the descendants of pro-eukaryotes might still thrive in the anoxic, porous ZnS edifices. 

Pnre cnltnres of organisms that can oxidize propionate either in the presence of a methanogen or nsing snlfate as electron acceptor have been obtained. These include both Syntrophobacter wolinii and Syntrophobacter pfenigii (Wallrabenstein et al. 1995). The interaction of two organisms, therefore, is clearly not obligatory for the ability to degrade these carboxylic acids under anaerobic conditions. 

For anaerobic bacteria, the same principles apply, except that additional attention must be directed to preparing the cell suspensions. Use of an anaerobic chamber in which cultures can be transferred to tightly capped centrifuge tubes is virtually obligatory, and addition of an anaerobic indicator should be used to ensure that subsequent entrance of oxygen does not take place inadvertently. On account of the inserts, screw-capped Oak Ridge tubes are convenient for centrifugation. 

Processes reported in Table 1 are typically anaerobic (AN). In agreement with the observations reported by Wuhrmann et al. [49], azo-dye bioconversion occurs with the standard organism and other facultative or obligatory aerobic bacteria in exclusively anoxic conditions. Different methods can be used to establish the required anaerobic conditions. A common procedure is simply sparging oxygen-free gas... 

As will be discussed further in this chapter, there is now much evidence to suggest that NO is an obligatory intermediate in the denitrification pathway. Furthermore, there is evidence that NH3 nitrifiers can synthesize the denitrification apparatus in addition to the nitrification apparatus and that the former system can produce NO and N2O (also N2 in at least one case) from nitrite under low partial pressures of O2. It is possible therefore that NO may be an intermediate in the denitrification activity of nitrifiers and so arise as a secondary consequence of NH3 oxidation. NO can also be ptoduced by nondenitrifying organisms under certain conditions. For example, NO can be slowly produced by the anaerobic reduction of nitrite, but only in absence of nitrate, by a variety of enteric bacteria. Some of the NO can be further reduced to N2O. 

Deposition of elemental sulphur formed from sulphate Essential collaboration of at least two different microbial species occurs in the transformation of sulphate to S° in salt domes or similar sedimentary formations (see Ivanov, 1968). This transformation is dependent on the interaction of a sulphate reducer like Desulfovibrio desulfuricans, which transforms sulphate to H2S in its anaerobic respiratory metabolism, and an H2S oxidizer like Thiobacillus thioparus, which, under conditions of limited O2 availability, transforms H2S to S° in its respiratory metabolism (van den Ende van Gemerden, 1993). The collaboration of these two physiological types of bacteria is obligatory in forming S° from sulphate because sulphate reducers cannot form S° from sulphate, even as a metabolic intermediate. It should be noted, however, that the sulphate reducers and H2S oxidizers are able to live completely independent of each other as long as the overall formation of S° from sulphate is not a requirement. 

Menon, S., and Ragsdale, S. W., 1996, Evidence that carbon monoxide is an obligatory intermediate in anaerobic acetyl-CoA synthesis, Biochem. 35(37) 12119nl2125. 

The interaction of two organisms is therefore clearly not obligatory for the ability to degrade these carboxylic acids under anaerobic conditions. 

The influence of plant sterols on the phase properties of phospholipid bilayers has been studied by differential scanning calorimetry and X-ray diffraction [206]. It is interesting that the phase transition of dipalmitoylglycerophosphocholine was eliminated by plant sterols at a concentration of about 33 mole%, as found for cholesterol in animal cell membranes. However, less effective modulation of lipid bilayer permeability by plant sterols as compared with cholesterol has been reported. The molecular evolution of biomembranes has received some consideration [207-209]. In his speculation on the evolution of sterols, Bloch [207] has suggested that in the prebiotic atmosphere chemical evolution of the sterol pathway if it did indeed occur, must have stopped at the stage of squalene because of lack of molecular oxygen, an obligatory electron acceptor in the biosynthetic pathway of sterols . Thus, cholesterol is absent from anaerobic bacteria (procaryotes). 

In contrast, MK is required under anaerobic conditions.Furthermore, when the organism is grown with fumarate, TMAO, or DMSO as electron acceptor, the presence of MK is obligatory." " When oxygen or nitrate is the electron acceptor, the aerobic quinone, ubiquinone, is used by E. coli Thus, while the conditions that favor the biosynthesis and function of Q are compatible with the biosynthesis of enterobactin, they are incompatible with the biosynthesis of MK. 

Akinterinwa, O. and Cirino, PC. (2011) Anaerobic obligatory xylitol production in Escherichia coli strains devoid of native fermentation pathways. Appl. Environ. Microbiol, 77, 706—709. 

The reduction of N2O to N2, carried by nitrous oxide reductases, N2ORS, is the last step of denitrification, and is also used as an independent respiratory process by certain anaerobic bacteria But the catalytic centers of native N2ORS known to date are almost exclusively copper-based. The Cu-containing N2OR from Wolinella contains an Fe-heme suggested to be a part of a dinuclear Cu-heme catalytic center . Though its role in the catalysis is controversial, the heme does seem to be obligatory for the activity of this enzyme . ... 

Private Kitchen waste More or less Biobin (from 2015 obligatory, Combined anaerobic digestion with... 

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