However amongst the most urgently needed products are environmentally friendly

However amongst the most urgently needed products are

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However, amongst the most urgently needed products are environmentally friendly gas hydrate inhibitors. This need is likely to become acute within the next two decades as the search for energy drives the industry to deeper waters and under the permafrost. Thus it is our hope that products isolated from psychrophiles will prove useful for the inhibition of gas hydrates. As previously indicated, AFPs inhibit the formation of gas hydrates [3, 4] and should repre- sent ideal ‘green inhibitors’. However, they currently cannot be produced in the volumes required for their practical application in the field. AFPs can be isolated from fish and insect serum, but these sources do not represent a reason- able option. Recombinant DNA technology has allowed the production of many foreign products in simple cells, but in this case, neither E. coli nor yeast cells can efficiently and accurately fold the same AFPs [48, 49] that are the most active against hydrates. The ability to screen psychrophiles for ice-associating properties should permit the identification of products that can also act as hydrate-associating molecules in order to change the kinetics of gas hydrate formation. Preliminary experiments in our labs (E. Huva, J.A. Ripmeester and V.K. Walker, unpub- lished) suggest that microbes with antifreeze as well as ice nucleating activities can influence hydrate formation. This is a significant finding since it represents a glimmer of hope that an affordable, environmentally benign method to control and inhibit hydrate formation may be found in microbes isolated by the selection techniques described in this chapter. Indeed, challenging and 2 Ice-Associating Proteins as ‘Green Inhibitors’ for Gas Hydrates 39
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expensive expeditions to polar regions, glaciers and high altitudes may not be required to prospect for microbes with ‘ice resistance’. It may be only necessary to continue to develop and use these strong selective techniques to recover those organisms with useful properties. It is hoped that microbial gene products can be more easily folded in bacterial vectors and that high levels of cost-effective production would be possible. Thus these microbes may reward us with reagents that can contribute to environmental safety and help secure a safe and effective methodology for the energy sector. 2.5 Conclusion Gas hydrate deposits will be important sources of energy in the future, as traditional sources of energy become more costly to exploit, and will undoubt- edly be used for gas storage and transportation. However, since the offshore industry is going to deeper waters, with consequent increased pressures and decreased temperatures, unpredicted hydrate formation is a major economic concern for industry. More significantly, the formation of these ‘fire ices’ are of environmental concern because of their blow out potential and the possible pollution linked to the use of chemical hydrate inhibitors. The need for green inhibitors is urgent and ice-associating proteins and glycoproteins offer the promise of environmentally safe alternatives. The described innovations for
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  • Winter '19
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  • Electrochemistry, MFCS, Renewable Energy Technology, Bruce E. Rittmann

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