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1.
Merete Grung Frances M. L. D'Souza Michael Borowitzka Synnøve Liaaen-Jensen 《Journal of applied phycology》1992,4(2):165-171
Aplanospores ofHaematococcus pluvialis MUR 145 contained 0.7% carotenoids (dry wt. basis) consisting of β,β-carotene (5% of total carotenoid), echinenone (4%),
canthaxanthin (4%), (3S,3′S)-astaxanthin diester (34%), (3S,3′S)-astaxanthin monoester (46%), (3S,3′S)-astaxanthin (1%) and (3R,3′R,6′R)-lutein (6%).
The astaxanthin esters were examined by TLC and HPLC and VIS,1H NMR and mass spectra recorded. Their chirality was determined by the camphanate method (Vecchi & Müller, 1979) after anaerobic
hydrolysis.
The tough cell wall of the aplanospores required enzymatic treatment prior to pigment extraction. The potential use of this
microalga as a feed ingredient in aquaculture is discussed briefly. 相似文献
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A simplified procedure for cDNA and genomic library construction using nonpalindromic oligonucleotide adaptors 总被引:2,自引:0,他引:2
The properties and characteristics of oligonucleotide adaptors for use in a simplified procedure for the construction of cDNA and genomic DNA libraries are described. The adaptors are suitable for joining to blunt ended cDNA or sheared genomic DNA, and then to the cohesive ends of restriction sites in vectors. Each adaptor consists of two oligonucleotides with complementary but nonpalindromic sequences that include an internal restriction site, a 5' phosphorylated blunt end, and an overlapping or staggered 5' hydroxylated end corresponding to a restriction endonuclease site in a vector of choice. Ligation of the blunt end to high molecular weight target DNA proceeds efficiently and there is no tandem concatenation of the adaptor. Insertion into the appropriate vector only requires ligation of the cohesive ends. There is no requirement for methylation, restriction enzyme cleavage, G-C tailing, or denaturation after ligation of the adaptor to the target DNA, all characteristics of other procedures. 相似文献
4.
R N D'Souza A L Bronckers R P Happonen D A Doga M C Farach-Carson W T Butler 《The journal of histochemistry and cytochemistry》1992,40(3):359-366
Rat dentin contains a major sialic acid-rich glycoprotein, DSP, with an overall composition similar to that of bone sialoproteins but whose biological role in dentinogenesis is unknown. Using polyclonal affinity-purified antibodies to rat DSP and four immunohistochemical methods of detection, we studied the cell and tissue localization of DSP and the time course of its appearance during odontoblast differentiation. DSP first appeared within young odontoblasts concomitant with early secretion of pre-dentin matrix and before the onset of mineralization but was absent in pre-odontoblasts. DSP immunostaining also localized within secretory odontoblasts and was intense in odontoblastic processes. Early pre-dentin stained positive for DSP, in contrast to more mature pre-dentin, where immunoreactivity was less intense and more restricted to odontoblastic processes. In the zone of mineralized dentin matrix, a moderate and uniform staining pattern was evident. Intense immunostaining was also seen within the cells and matrix of dental pulp during dentinogenesis. Other cells and tissues within the tooth organ and those surrounding it were non-reactive. These findings suggest that DSP is developmentally expressed in cells of the odontoblastic lineage and may be a biochemical marker of odontoblastic activity. 相似文献
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Miyazaki Y Irobalieva RN Tolbert BS Smalls-Mantey A Iyalla K Loeliger K D'Souza V Khant H Schmid MF Garcia EL Telesnitsky A Chiu W Summers MF 《Journal of molecular biology》2010,404(5):751-772
The 5′-untranslated regions of all gammaretroviruses contain a conserved “double-hairpin motif” (ΨCD) that is required for genome packaging. Both hairpins (SL-C and SL-D) contain GACG tetraloops that, in isolated RNAs, are capable of forming “kissing” interactions stabilized by two intermolecular G-C base pairs. We have determined the three-dimensional structure of the double hairpin from the Moloney murine leukemia virus ([ΨCD]2, 132 nt, 42.8 kDa) using a 2H-edited NMR-spectroscopy-based approach. This approach enabled the detection of 1H-1H dipolar interactions that were not observed in previous studies of isolated SL-C and SL-D hairpin RNAs using traditional 1H-1H correlated and 1H-13C-edited NMR methods. The hairpins participate in intermolecular cross-kissing interactions (SL-C to SL-D′ and SLC′ to SL-D) and stack in an end-to-end manner (SL-C to SL-D and SL-C′ to SL-D′) that gives rise to an elongated overall shape (ca 95 Å × 45 Å × 25 Å). The global structure was confirmed by cryo-electron tomography (cryo-ET), making [ΨCD]2 simultaneously the smallest RNA to be structurally characterized to date by cryo-ET and among the largest to be determined by NMR. Our findings suggest that, in addition to promoting dimerization, [ΨCD]2 functions as a scaffold that helps initiate virus assembly by exposing a cluster of conserved UCUG elements for binding to the cognate nucleocapsid domains of assembling viral Gag proteins. 相似文献
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Avinash Kale Ramesh S. Hire Ashok B. Hadapad Stanislaus F. D'Souza Vinay Kumar 《Insect biochemistry and molecular biology》2013,43(11):1045-1054
The two components (BinA and BinB) of Lysinibacillus sphaericus binary toxin together are highly toxic to Culex and Anopheles mosquito larvae, and have been employed world-wide to control mosquito borne diseases. Upon binding to the membrane receptor an oligomeric form (BinA2.BinB2) of the binary toxin is expected to play role in pore formation. It is not clear if these two proteins interact in solution as well, in the absence of receptor. The interactions between active forms of BinA and BinB polypeptides were probed in solution using size-exclusion chromatography, pull-down assay, surface plasmon resonance, circular dichroism, and by chemically crosslinking BinA and BinB components. We demonstrate that the two proteins interact weakly with first association and dissociation rate constants of 4.5 × 103 M?1 s?1 and 0.8 s?1, resulting in conformational change, most likely, in toxic BinA protein that could kinetically favor membrane translocation of the active oligomer. The weak interactions between the two toxin components could be stabilized by glutaraldehyde crosslinking. The cross-linked complex, interestingly, showed maximal Culex larvicidal activity (LC50 value of 1.59 ng mL?1) reported so far for combination of BinA/BinB components, and thus is an attractive option for development of new bio-pesticides for control of mosquito borne vector diseases. 相似文献