Autotroph facultative

Photolithotrophs h Chlorobium, Chromatium 4, 6,8 taining marine and fresh water environments. HjS-containing muds and stagnant N0 anaerobically autotrophic, facultatively autotrophic or mixo-trophic deriving energy from sulfur oxidation autotrophic status of Beggiatoa uncertain. Photosynthetic, strict anaerobes ... 

A facultative autotroph (lithotroph) strain MLHE-1 was able to oxidize arsenite under anaerobic conditions to arsenate using nitrate as electron acceptor (Oremland et al. 2002). 

Microorganisms at aqueous-solid phase interfaces have different respiration modes which include (a) aerobic heterotrophic, (b) aerobic autotrophic, (c) facultative anaerobic heterotrophic, (d) facultative anaerobic autotrophic, and (e) anaerobic heterotrophic respiration modes [36,41,43,47, 55]. Table 3 shows the main differences between these different respiration modes. 

The best example for facultative anaerobic autotrophic respiration is represented by Thiobacillus denitrificans, as shown in the denitrification reaction g ... 

There are differences in the pathways of thiamin hiosynthesis between prokaryotes and eukaryotes, and also between organisms that are aerobes and facultative anaerobes. Some organisms are completely autotrophic for thiamin, whereas others require the presence of either preformed pyrimidine or thiazole in the culture medium, and indeed some require both. 

Chistoserdov, A. Y., Biyd, G., Mathews, F. S., and Lidstrom, M. E., 1992, The genetic organization of the mau gene cluster of the facultative autotroph Paracoccus denitrifrcans, Biochim. Biophys. Res. Commun. 184 1226nl234. 

Within the sulphur-dependent thermophilic branch of the archaebacteria, the situation is less clear. Sulfolobus species are facultatively autotrophic [13] and many of the citric acid cycle enzymes have been reported (reviewed in ref. [1]). Thus, when growing heterotrophically in the presence of oxygen, an oxidative cycle may be operative, although respirometric analyses suggest that its use may be limited [13]. 

Wood A. P. and Kelly D. P. (1989) Isolation and physiological characterization of Thiobacillus thyasyris sp. nov., a novel marine facultative autotroph and putative symbiont of Thyasira flexuosa. Arch. Microbiol. 152, 160-162. 

If inorganic substrates are replaced by organic substrates in the culture medium, then contamination may result from the growth of heterotrophic Acidiphilium species or facultatively autotrophic Thiobacillus acidophilus (see Section II,A,5). 

Typical chemolithotrophic bacteria are the thiobacilli (Vishniac and Santer, 1957 Trudinger, 1967), Many of these are strict autotrophs but facultative autotrophs and mixotrophic species have been described (e.g. Trudinger, 1969 Rittenberg, 1969). 

Order Genus Optimal growth temperature (°C) Heterotrophic (het) autotrophic (aut) facultative autotrophic (f) Anaerobic (an) aerobic (ae)... 

The terms obligate and facultative are also used obligate organisms can only use that form of nutrition, whilst facultative can switch from one form to another. The most common example of facultative organisms is the algae, many of which are photo autotrophs in the light, but may be chemoheterotrophs in the dark. 

Leptothrix ochracea is facultatively autotrophic and can also utilize organic substances. The filaments are never branched or attached. 

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