Microbes genetic manipulation

In addition to the amount of pesticide present, the degradation rate could be affected by the availability of the chemical for degradation. Ogram et al. (30) have recently presented evidence suggesting that only the 2,4-D (2,4-dichloro phenoxyacetic acid) in soil solution, but not that adsorbed on soil colloids, could be degraded by soil microbes both in soil solution and sorbed on soil colloids. Other considerations should also be given to the nature and quantity of soil microbial biomass present in relation to nutrient availability (26,28,31) and the adaptability of microbes, either by natural selection or by genetic manipulation, to attack and utilize the pesticide chemical (32). 

Microbial production of carotenoids is an environmentally friendly method compared to chemical methods. The availability of carotenoid genes from carotenogenic microbes has made possible the synthesis of carotenoids in non-carotenogenic microbes [80]. E. coli, because of its ease for genetic manipulation, is considered a suitable host for carotenoid production and is able to make various carotenoids such as lycopene, P-carotene, canthaxanthin, zeaxanthin, and astaxanthin [81-83]. 

Even though environmental toxicology could have profound effects on the HS response, there are other considerations where manipulation of the HS response could be beneficial. For example, constitutive induction of the HS response in bacteria could be a potential means to develop super-microbes which could withstand harsh environments while engaging in their genetically-designed function such as scouring oil spills and enzymatically converting toxins into harmless substances. 

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