Genetic Engineering for Abiotic Stress Tolerance in Agricultural Crops

Microbial Enzymes: Tools for Biotechnological Processes

“…Our ability to tap into such immense biodiversity depends on the tools available to expand the search for new enzymes by (i) metagenome screening [6,7,8,9,10]); (ii) genome mining in more than 2,000 sequenced microbial genomes [11,12,13,14]; and (iii) exploring the diversity of extremophiles [15,16]).…”

“…Due to their capability to survive under environments of extreme conditions, both physical as temperature (−2 to 12 °C, 60–110 °C), pressure or radiation, and geochemical such as salinity (2–5 NaCl) and pH (<2, >9), extremophiles are a very interesting source of enzymes with extreme stability under conditions regarded as incompatible with biological materials. Recent studies show that the diversity of organisms in these extreme environments could be even greater than was initially thought [16,44]. However, because the majority of these microorganisms have not yet been isolated in pure culture, useful characterization of their enzymes still remains quite difficult.…”

“…Thermophilic proteases, lipases as well as cellulases and amylases are being used in many different industrial applications [16,45]. Extreme thermophiles (growing at 60–80 °C) are widely distributed among several bacterial genera such as Clostridium , Thermus , Thermotoga , and Bacillus , whereas most of hyperthermophiles belong to Archaea such as Pyrococcus , Thermococcus or Methanopyrus , among others.…”

“…Polymer-degrading activities (e.g., cellulases, xylanases,) are quite interesting for the pulp and paper industry, as well as for saccharification of pre-treated lignocellulosic biomass for the production of second generation biofuels [47]. These cold-active enzymes also have potential for many other applications [16,48], such as extraction and clarification of fruit juices, improvement of bakery products, polishing and stone-washing of textiles, and bioremediation of waters contaminated with oils or hydrocarbons [49]. …”

Amelioration of salt stress in chickpea (Cicer arietinum L.) by coinculation of ACC deaminase-containing rhizospheric bacteria with Mesorhizobium strains

“…To minimize the impact of soil salinity on agriculture production, substantial efforts have been made in development of salt-tolerant cultivars by conventional breeding and genetic engineering (Roy et al, 2011). However, the performance of these genetically modified salttolerant cultivars is usually poor when they are grown under field conditions (Ashraf et al, 2008).…”