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991.
992.
K. Srinivasa Babu T. Muthukumaran Aju Antony S. D. Prem Singh Samuel M. Balamurali V. Murugan S. Meenakshisundaram 《Biotechnology letters》2009,31(5):659-664
Human granulocyte-macrophage colony stimulating factor (hGMCSF) is an important therapeutic cytokine. As a novel attempt to
purify hGMCSF protein, without the enzymatic cleavage of the affinity tag, an intein-based system was used. The gene was fused
by overlap extension PCR to the intein sequence at its N-terminal in pTYB11 vector. The hGMCSF was expressed as a fusion protein in E. coli BL21(DE3), and E. coli GJ1158. In the former, the protein was expressed as inclusion bodies and upon purification the yield was 7 mg/l with a specific
activity of 0.5 × 107 IU/mg. In salt-inducible E. coli GJ1158, hGMCSF was expressed in a soluble form at 20 mg/l and a specific activity of 0.9 × 107 IU/mg. The intein-hGMCSF was purified on a chitin affinity column by cleaving intein with 50 mM DTT resulting in a highly
pure 14.7 kDa hGMCSF. 相似文献
993.
994.
995.
SYNOPSIS. Two species of hymenostome ciliates, Uronema filificum, and U. elegans, are described from the Atlantic coast. Studies were made on specimens treated with the Chatton-Lwoff silver impregnation technic, and particular attention was given to the buccal infraciliature. 相似文献
996.
EDWARD J. KLEKOWSKI JR. F.L.S. 《Botanical journal of the Linnean Society. Linnean Society of London》1973,66(2):181-188
Hybridization experiments indicate that Pteridium aquilinum from Hawaii and P. aquilinum from the Galapagos Isles are intersterile. Both of these populations will cross readily with other New World collections of Pteridium. Evidence suggests that the Galapagos populations are genetically distinct from the South American populations. The genetic divergence of the Galapagos populations has not been accompanied by morphological divergence. 相似文献
997.
Recent advances in banding techniques have led to the belief that certain chromosomal defects are consistently associated with specific types of human neoplasia. Based on the GTG technique, it has been suggested that the malignant cells of most neoplasias show chromosomal abnormalities (Yunis et al. 1983). From this recent publication of Yunis it appears that the majority of bands involved in carcinogenesis are G-negative, i.e., do not stain by the GTG technique, and it is therefore difficult to localize the breakpoints. In some of our recent publications we emphasized the importance of the RFA technique (Verma and Lubs 1975), which stains Giemsa-negative bands darkly, thus providing precise identification of chromosomal abnormalities (Verma and Dosik 1976). However, this technique cannot be applied until the slides have aged for at least 7 days. Therefore, we are reporting an alternative procedure using BrdU which provides “reverse” banding immediately when the slides are stained with acridness orange and examined with a fluorescence microscope. 相似文献
998.
Summary We suggest that the short arms of human chromosome 15 (15p) exhibit intensity heteromorphisms by DA/DAPI technique. A method for classification of variable intensities is proposed. The different intensities can be classified into at least five classes. They are: negative, pale, medium, intense, and brilliant. Therefore we suggest that 15p is not always positive by DA/DAPI technique. The present findings reveal that the heteromorphism on 15p is far greater than previously thought. 相似文献
999.
Jayasudha Srinivasa Balasubramaniam Arun Vinod Kumar Mishra Gyanendra Pratap Singh Govindan Velu Raman Babu Neeraj Kumar Vasistha Arun Kumar Joshi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(7):1643-1651
Key message
Ten QTL underlying the accumulation of Zn and Fe in the grain were mapped in a set of RILs bred from the cross Triticum spelta × T. aestivum . Five of these loci (two for Zn and three for Fe) were consistently detected across seven environments.Abstract
The genetic basis of accumulation in the grain of Zn and Fe was investigated via QTL mapping in a recombinant inbred line (RIL) population bred from a cross between Triticum spelta and T. aestivum. The concentration of the two elements was measured from grain produced in three locations over two consecutive cropping seasons and from a greenhouse trial. The range in Zn and Fe concentration across the RILs was, respectively, 18.8–73.5 and 25.3–59.5 ppm, and the concentrations of the two elements were positively correlated with one another (rp =+0.79). Ten QTL (five each for Zn and Fe accumulation) were detected, mapping to seven different chromosomes. The chromosome 2B and 6A grain Zn QTL were consistently expressed across environments. The proportion of the phenotype explained (PVE) by QZn.bhu-2B was >16 %, and the locus was closely linked to the SNP marker 1101425|F|0, while QZn.bhu-6A (7.0 % PVE) was closely linked to DArT marker 3026160|F|0. Of the five Fe QTL detected, three, all mapping to chromosome 1A were detected in all seven environments. The PVE for QFe.bhu-3B was 26.0 %. 相似文献1000.
Sonal Dalvi Carla Nicholson Fares Najar Bruce A. Roe Patricia Canaan Steven D. Hartson Babu Z. Fathepure 《Applied and environmental microbiology》2014,80(21):6664-6676
Arhodomonas sp. strain Seminole was isolated from a crude oil-impacted brine soil and shown to degrade benzene, toluene, phenol, 4-hydroxybenzoic acid (4-HBA), protocatechuic acid (PCA), and phenylacetic acid (PAA) as the sole sources of carbon at high salinity. Seminole is a member of the genus Arhodomonas in the class Gammaproteobacteria, sharing 96% 16S rRNA gene sequence similarity with Arhodomonas aquaeolei HA-1. Analysis of the genome predicted a number of catabolic genes for the metabolism of benzene, toluene, 4-HBA, and PAA. The predicted pathways were corroborated by identification of enzymes present in the cytosolic proteomes of cells grown on aromatic compounds using liquid chromatography-mass spectrometry. Genome analysis predicted a cluster of 19 genes necessary for the breakdown of benzene or toluene to acetyl coenzyme A (acetyl-CoA) and pyruvate. Of these, 12 enzymes were identified in the proteome of toluene-grown cells compared to lactate-grown cells. Genomic analysis predicted 11 genes required for 4-HBA degradation to form the tricarboxylic acid (TCA) cycle intermediates. Of these, proteomic analysis of 4-HBA-grown cells identified 6 key enzymes involved in the 4-HBA degradation pathway. Similarly, 15 genes needed for the degradation of PAA to the TCA cycle intermediates were predicted. Of these, 9 enzymes of the PAA degradation pathway were identified only in PAA-grown cells and not in lactate-grown cells. Overall, we were able to reconstruct catabolic steps for the breakdown of a variety of aromatic compounds in an extreme halophile, strain Seminole. Such knowledge is important for understanding the role of Arhodomonas spp. in the natural attenuation of hydrocarbon-impacted hypersaline environments. 相似文献