Symbiotic degradation

Symbiotic Degradation of PEG. The symbiotic mixed culture composed of Flavobacterium species and Pseudomonas species was obtained as a PEG 20,000-utilizing microbial system, as described above. The symbiotic mechanism of the mixed culture was examined as follows. 

Figure 4. Symbiotic Degradation of PEG by Flavobacterium sp. and Pseudomonas sp. GOA glyoxylic acid. (Reproduced with permission from Ref. 1. Copyright 1987 CRC Press, Inc.)...

Mechanism of symbiotic degradation of PEG (adapted from Kawai and Yamanaka, 1986). 

This pathway is also important for ruminant animals, which are dependent on symbiotic microorganisms to break down their food. The microorganisms produce large amounts of propionic acid as a degradation product, which the host can channel into the metabolism in the way described. 

Microbial communities dealing with different substrates are stable and successful systems, as they are able to react to different availabihty of resources. Data on the further integration of PVA-degrading symbiotic communities in such networks involving also PVA blended components and other substrates have not yet been described in detail. 

Ghosh and co-workers have shown in several studies that Brij 35 and Pol 10 in water provide suitable environments for the photochemically induced reductive dechlorination of chlorobiphenyls [75,77,82,83]. Ghosh and Sayler have demonstrated that photochemistry and microbes work symbiotically to degrade PCB mixtures [76,80]. Photochemistry in a surfactant/water solution converts highly chlorinated biphenyls into much less chlorinated ones. The microbes, which do not oxidize the highly chlorinated biphenyls, then oxidize the less chlorinated biphenyls. For a related study on the combined degradation of a PCB mixture and microbes see [88]. 

The phytoremediation process may be viewed as a symbiotic process between plants and soil microbes that involved in phytoremediation (Lasat, 2002). Plant and bacterial interaction can enhance the effectiveness of phytoremediation technology because plants provide carbon and energy sources or root exudates in the rhizosphere that will support microbial community in the degradation and transformation of soil pollutants (Siciliano and Germida, 1998). In addition, the presence of soil microbes can increase the water solubility or bioavailability of pollutants in soils, which facilitates the uptake of pollutants by plants (Lasat, 2002 Siciliano and Germida, 1998). However, the specificity of the plant-bacteria interactions besides being much intricate is dependent upon soil and the aqueous conditions, which can alter contaminant... 

Others (Foster et al., 2007 Kimor et al., 1978 ViUareal, 1989) have reported that vegetative ceUs degrade first, and often the heterocysts are the last part of the Richelia trichome to remain in a host diatom, which could also suggest host control or some sort of ceU signaUng between host and symbiont. Gomez et al. (2005) observed Calothrix symbionts associated with Chaetoceros diatoms which lacked chloroplasts suggesting that the host diatoms were senescent quite possibly though the symbiotic... 

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