Biofortification is an upcoming, promising, cost-effective, and sustainable technique of delivering micronutrients to a population that has limited access to diverse diets and other micronutrient interventions. Unfortunately, major food crops are poor sources of micronutrients required for normal human growth. The manuscript deals in all aspects of crop biofortification which includes—breeding, agronomy, and genetic modification. It tries to summarize all the biofortification research that has been conducted on different crops. Success stories of biofortification include lysine and tryptophan rich quality protein maize (World food prize 2000), Vitamin A rich orange sweet potato (World food prize 2016); generated by crop breeding, oleic acid, and stearidonic acid soybean enrichment; through genetic transformation and selenium, iodine, and zinc supplementation. The biofortified food crops, especially cereals, legumes, vegetables, and fruits, are providing sufficient levels of micronutrients to targeted populations. Although a greater emphasis is being laid on transgenic research, the success rate and acceptability of breeding is much higher. Besides the challenges biofortified crops hold a bright future to address the malnutrition challenge.

To study the functions of the 13 gyp genes, gvpMLKJIHGFEDACN, on plasmid pNRC100 of Halobacterium halobium in gas vesicle formation, we carried out linker scanning mutagenesis of the gene cluster. We constructed a 24.5-kb Escherichia coli-H. halobium shuttle plasmid, pFL2, containing the gyp gene cluster and introduced a kanamycin resistance (K) cassette into each gene (except for gvpA). Transformation of H. halobium SD109, which had the entire gyp gene cluster deleted, with pFL2 and mutated pFL2 derivatives showed that while the unmutated gene cluster successfully programmed gas vesicle formation, derivatives with insertion of the c cassette in any of the gyp genes, except gvpM, did not lead to production of normal gas vesicles. Insertions in gvpL, -K, -J, -I, and -F resulted in a complete block in gas vesicle synthesis, while insertions in gvpH, -G, -E, -D, -C, and -N resulted in greatly reduced gas vesicle synthesis. In most cases, the block in gas vesicle synthesis did not result from polar effects, since similar results were obtained for derivatives of the insertion mutants in which most of the internal portion of the K cassette was deleted and only small (15 to 54-bp) insertions remained. The only exceptions were for gvpH and gvpD, where deletion of the internal portion of the K insertions resulted in phenotypic reversion. Electron microscopic analysis of the K mutants revealed that interruptions of gvpC and gvpN result in the formation of smaller gas vesicles than in the wild type, while interruptions ofgvpF, -G, -H, -I, -J, -K, and -L produce no discernible vesicle intermediates. These results indicate that gvpA, -C, and -N, which have the rightward transcriptional orientation, encode structural proteins, with gvpC and gvpN necessary for late stages of vesicle formation, and gvpL,

Halophiles are salt‐loving organisms that inhabit hypersaline environments. They include mainly prokaryotic and eukaryotic microorganisms with the capacity to balance the osmotic pressure of the environment and resist the denaturing effects of salts.

No abstract

No abstract