Kinetics of uranous iron and ferrous iron oxidation by thiobacillus ferrooxidans

Archives of Microbiology -     

Fast chlorophyll fluorescence transient and nitrogen fixing ability of chickpea nodulation variants

High nodulating (HN) selections of the cultivars ICC 4948 and ICC 5003 had the highest nodule number and nodule dry mass followed by low nodulating (LN) selections of the same cultivar. Both non-nodulating (NN) selections of cv. ICC 4993 and ICC 4918 did not show any nodule. Using N-difference method the HN selection of cv. 1CC 4948 was able to meet 73 % of its demand of N through biological fixation of N₂ [P(fix)], while 27 % of N demand was met by uptake from the soil, whereas its LN selection was able to meet only 54 % of its demand of N through biological fixation of N₂. Similarly in cv. ICC 5003 HN and LN selections the P(fix) was 76 and 64 %, respectively. Fast chlorophyll (Chl) fluorescence transient data analysis showed that performance index PI(abs) was 62.0 in cv. ICC 4948 HN selection and 44.5 in its respective LN selections. Corresponding values for cv. ICC 5003 were 32.4 and 28.4. In NN selections of ICC 4993 and ICC 4918 it was 12.6 and 30.7, respectively. Structure function index of the plants SFI(abs) and driving force for photosynthesis (DF) were highest in the HN selections followed by LN selections and lowest in the NN selections. The total uptake of N by chickpea plants was significantly and positively correlated with the density of reaction centres ABS/CS₀, TR₀/CS₀, and DI₀/CS_M, whereas total N uptake by chickpea seeds was significantly positively correlated with N and TR₀/CS₀. The percentage of P(fix) was highly significantly positively correlated with N, the so-called turnover number which indicates how many times Q_A has been reduced in the time span from 0 to t_Fmax and TR₀/CS₀. Fast Chl a fluorescence measurement can be used as a model system to assess the N fixation ability in chickpea.     

Pollen morphology of Euphorbia caputmedusae

A particular pollen type is observed in the species Euphorbia caputmedusae which is distributed in South Africa. The exine of this pollen is clearly rugulose and beset with coarse granules. In addition 10 to 25% of the pollen grains are heteropolar and have a characteristic aperture type which is something between tricolporate and parasyncolpate. The pollen morphology of this species gives grounds for suggesting its removal from the section Euphorbium to a separate section, as suggested by Carter (1988).     

Levanases for control of slime in paper manufacture

Formation of slime deposits is a major problem facing paper industries. The slime may be biological or nonbiological. Biological deposits that are composed of varied microflora along with fibers, fillers and dirt are the most troublesome. Slime producing microbes secrete extracellular polysaccharides that gum up the process machinery. The specific nature of slime and its formation depend on the mill environment. Correspondingly, countermeasures vary with the type of slime deposit. Conventional slime control methods generally employ combinations of biocides. This leads to effluent toxicity, as well as high processing and treatment costs. Therefore, alternative control measures are in demand. Once such measure is the use of enzymes (levanases) that dissolve the slime to some degree and improve biocide penetration into the slime layer. As a result, the amount of biocide required is reduced, process economics improve and effluent treatment is simplified.     

Inhibition of Tumor Necrosis Factor Alpha (TNFα) Expression and Function In Vitro by Modified Antisense Oligonucleotides

Abstract

Antisense oligonucleotides containing C-5 hexynyl/propynyl modified pyrimidines were synthesized using solid phase phosphoramidite chemistry. These modified oligonucleotides were found to have significant inhibitory activity against TNFα production in vitro.     

Dominance of Methanomicrobium phylotype in methanogen population present in Murrah buffaloes (Bubalus bubalis)

Aims:  To study the diversity of rumen methanogens in Murrah buffaloes ( Bubalus bubalis ) from North India by using 16S rRNA gene libraries obtained from the pooled rumen content from four animals and using suitable software analysis.
Methods and Results:  Genomic DNA was isolated and PCR was set up by using specific primers. Amplified product was cloned into a suitable vector and the positive clones were selected on the basis of blue–white screening and sequenced. The resulting nucleotide sequences were arranged in the phylogenetic tree. A total of 108 clones were examined, revealing 17 different 16S rRNA gene sequences or phylotypes. Of the 17 phylotypes, 15 (102 of 108 clones) belonged to the genus Methanomicrobium , indicating that the genus Methanomicrobium is the most dominant component of methanogen populations in Murrah buffaloes ( Bubalus bubalis ) from North India. The largest group of clones (102 clones) was more than 98% similar to Methanomicrobium mobile . BLAST analysis of the rumen contents from individual animals also revealed 17 different phylotypes with a range of 3–10 phylotypes per animal.
Conclusion:  Methanomicrobium phylotype is the most dominant phylotype of methanogens present in Murrah buffaloes ( Bubalus bubalis ).
Significance and Impact of the Study:  Effective strategies can be made to inhibit the growth of Methanomicrobium phylotype to reduce the methane emission from rumen contents and thus help in preventing global warming.