Manganese biomining: A review

Biomining comprises of processing and extraction of metal from their ores and concentrates using microbial techniques. Currently this is used by the mining industry to extract copper, uranium and gold from low grade ores but not for low grade manganese ore in industrial scale. The study of microbial genomes, metabolites and regulatory pathways provide novel insights to the metabolism of bioleaching microorganisms and their synergistic action during bioleaching operations. This will promote understanding of the universal regulatory responses that the biomining microbial community uses to adapt to their changing environment leading to high metal recovery. Possibility exists of findings ways to imitate the entire process during industrial manganese biomining endeavor. This paper reviews the current status of manganese biomining research operations around the world, identifies factors that drive the selection of biomining as a processing technology, describes challenges in exploiting these innovations, and concludes with a discussion of Mn biomining’s future.     

Vascular gene polymorphisms (EDNRA -231 G>A and APOE HhaI) and risk for migraine

Migraine is a neurovascular disorder, and hence, any alteration in vascular endothelial function by either the endothelin system or the apolipoproteins may contribute to its pathophysiology. Thus, we investigated the role of EDNRA -231 G>A and APOE HhaI polymorphism for a possible association with migraine. Genotyping of 613 subjects consisting of 217 migraine subjects, 217 healthy controls (HC), and 179 subjects with tension-type headache was performed using the standard PCR-RFLP method. Data were analyzed by taking the Bonferroni-corrected p-values into account. We found significant difference in the frequency of EDNRA AA genotype between migraine subjects when compared with HC (p-value?=?0.005; OR?=?2.542; confidence interval [CI]?=?1.329-4.863). A similar trend was shown by female migraine subjects at genotype and allele levels. The association of EDNRA -231 G>A polymorphism with migraine fit a recessive model (migraine vs. HC, p-value?=?0.002; OR?=?1.917; CI?=?2.268-2.898). Female migraineurs without aura (MO) followed a similar trend. In the case of APOE HhaI polymorphism, E3E4 and E2E3 genotypes conferred risk when taken together in case of migraine versus HC (p-value?=?0.005; OR?=?2.715; CI?=?1.342-5.490) and migraine with aura (MA) versus HC (p-value?=?0.004; OR?=?3.422; CI?=?7.992). The risk was also seen after stratification on the basis of gender in female migraineurs (total migraine and MA). The interaction of EDNRA and APOE genotypes did not show further significance. The AA genotype and A allele of EDNRA -231 G>A polymorphism conferred risk for total migraine and MO. In APOE HhaI polymorphism, E3E4 and E2E3 conferred risk when taken together in total migraine and MA.     

Camptothecin-somatostatin conjugates inhibit the growth of small cell lung cancer cells

The effects of camptothecin-somatostatin (CPT-SS) conjugates were investigated on small cell lung cancer (SCLC) cells. CPT was coupled to a SS agonist (SSA), c(Cys-Phe-DTrp-Lys-Thr-Cys)Thr-NH2 using the built in nucleophile assisted-releasing group (L1) N-methyl-aminoethyl-Gly-Dser-Nle-Dtyr-Dser or (L2) aminoethyl-Gly-Dser-Nle-Dtyr-Dser. The resulting CPT-L1-SSA and CPT-L2-SSA inhibited the specific binding of [125I-Tyr11]SS to NCI-H69 cell membranes with IC50 values of 0.2 and 2.1 nM, respectively. [125I]CPT-L1-SSA was internalized by SCLC cells at 37 degrees C but not at 4 degrees C. CPT-L1-SSA and CPT-L2-SSA inhibited in a dose-dependent manner the increase in adenylylcyclase activity caused by 25 microM forskolin. In vitro, 0.3 microM CPT-L1-SSA half-maximally inhibited the clonal growth of SCLC cells and 1 microM CPT-L1-SSA strongly inhibited 3H-thymidine incorporation into DNA and trypan-blue exclusion. These results suggest that CPT conjugated peptides such as CPT-L1-SSA may prove useful for exploring the efficacy of receptor-directed cytotoxicity to inhibit the proliferation of SCLC cells.     

Mapping and tagging of seed coat colour and the identification of microsatellite markers for marker-assisted manipulation of the trait in Brassica juncea

Microsatellite marker technology in combination with three doubled haploid mapping populations of Brassica juncea were used to map and tag two independent loci controlling seed coat colour in B. juncea. One of the populations, derived from a cross between a brown-seeded Indian cultivar, Varuna, and a Canadian yellow-seeded line, Heera, segregated for two genes coding for seed coat colour; the other two populations segregated for one gene each. Microsatellite markers were obtained from related Brassica species. Three microsatellite markers (Ra2-A11, Na10-A08 and Ni4-F11) showing strong association with seed coat colour were identified through bulk segregant analysis. Subsequent mapping placed Ra2-A11 and Na10-A08 on linkage group (LG) 1 at an interval of 0.6 cM from each other and marker Ni4-F11 on LG 2 of the linkage map of B. juncea published previously (Pradhan et al., Theor Appl Genet 106:607–614, 2003). The two seed coat colour genes were placed with markers Ra2-A11 and Na10-A08 on LG 1 and Ni4-F11 on LG 2 based on marker genotyping data derived from the two mapping populations segregating for one gene each. One of the genes (BjSC1) co-segregated with marker Na10-A08 in LG 1 and the other gene (BjSC2) with Ni4-F11 in LG 2, without any recombination in the respective mapping populations of 130 and 103 segregating plants. The identified microsatellite markers were studied for their length polymorphism in a number of yellow-seeded eastern European and brown-seeded Indian germplasm of B. juncea and were found to be useful for the diversification of yellow seed coat colour from a variety of sources into Indian germplasm.