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71.
72.
R T Venkatachalapathy Arjava Sharma Soumi Sukla Tarun K Bhattacharya 《DNA sequence》2008,19(3):177-184
The present study was carried out to characterize the DGAT1 gene of Riverine buffalo. Total RNA was extracted from the mammary tissue of buffalo and DGAT1cDNA were synthesized by RT-PCR, then cloned using pDRIVE cloning vector and sequenced. The sequencing revealed that the size of DGAT1 gene was 1470 bp with GC content of 62.30%. The gene encoded for 489 amino acid precursors and that it possessed 32 amino acids signal peptide. The similarity of buffalo DGAT1 mRNA sequence with that of cattle, pig, monkey, human, mice and rat were determined as 98.4, 90.7, 85.4, 85.0, 77.4 and 77.1%, respectively. Phylogenetic tree constructed from the derived DGAT1 protein sequences of 15 different species illustrated a unique branches for mammals, fly, nematode and plants. Among mammals, cattle and buffalo grouped together, whereas swine formed another group in the same branch. Four motifs were predicted in buffalo DGAT1 peptide sequence, one N-linked glycosylation site (246th position), two putative tyrosine phosphorylation site (316 and 261), one putative diacylglycerol binding site (382-392 amino acid position) and a conserved domain MBOAT (membrane bound acyl transferase from 150 to 474 amino acids) with a histidine as an active residue. 相似文献
73.
74.
The arbuscular mycorrhizal status of fifteen mangroves and one mangrove associate was investigated from 27 sites of three
inundation types namely, diurnal, usual springtide and summer springtide. Roots and rhizospheric soil samples were analysed
for spore density, frequency of mycorrhizal colonization and some chemical characteristics of soil. Relative abundance, frequency
and spore richness of AMF were assessed at each inundation type. All the plant species except Avicennia alba exhibited mycorrhizal colonization. The study demonstrated that mycorrhizal colonization and spore density were more influenced
by host plant species than tidal inundation. Forty four AMF species belonging to six genera, namely Acaulospora, Entrophospora, Gigaspora, Glomus, Sclerocystis and Scutellospora, were recorded. Glomus mosseae exhibited highest frequency at all the inundation types; Glomus fistulosum, Sclerocystis coremioides and Glomus mosseae showed highest relative abundance at sites inundated by usual springtides, summer springtides and diurnal tides, respectively.
Spore richness of AMF was of the order usual springtide > diurnal > summer springtide inundated sites. The mean spore richness
was 3.27. Diurnally inundated sites had the lowest concentrations of salinity, available phosphorus, exchangeable potassium,
sodium and magnesium. Statistical analyses indicated that mycorrhizal frequency and AMF spore richness were significantly
negatively correlated to soil salinity. Spore richness was also significantly negatively correlated to available phosphorus.
The soil parameters of the usual springtide inundated sites appeared to be favourable for the existence of maximum number
of AMF. Glomus mosseae was the predominant species in terms of frequency in the soils of the Sundarbans. 相似文献
75.
Dip K. Gogoi Hari P. Deka Boruah Ratul Saikia Tarun C. Bora 《World journal of microbiology & biotechnology》2008,24(1):79-87
An endophytic fungus having antifungal and antibacterial properties was isolated from Taxus wallichiana of Arunachal Pradesh, India. On the basis of morphological and molecular characteristics, the fungus was identified as Fusarium sp. and designated as DF2. The fungus was optimized for growth and maximum production of the antimicrobial agent. Media with
5% leaf extract (w/v) supplemented with 0.1% dextrose as carbon and yeast extract as nitrogen source favored the growth with
temperature optimum 25 ± 2°C and pH 6. Incubation period of 10 days was observed optimum for growth and production of antimicrobial
agent. Phenylalanine and dextrose enriched basal medium promoted the antimicrobial agent production, whereas methionine amended
in combination with glucose promoted higher biomass accumulation. The TLC purified active compound with UV λ-max 270 nm in
ethyl acetate has got the lowest minimum inhibitory concentration (MIC) against Bacillus subtilis, Staphylococcus aureus and Escherichia coli and highest against Pseudomonas aeruginosa. 相似文献
76.
Photosynthesis and water efflux were measured in different PAR and stomatal conductance in members of Avicenniaceae and Rhizophoraceae.
Trend of leaf temperature with irradiance and its effect on photosynthesis were also estimated. In most of the studied species,
photosynthesis and stomatal conductance followed similar trends with increase in irradiance. The rate of net photosynthesis
and stomatal conductance were higher in members of Avicenniaceae than in Rhizophoraceae. In Avicenniaceae, the optimum PAR
for maximum photosynthesis ranged between 1340–1685 (μmol m-2s-1, which was also higher than that of Rhizophoraceae (840-1557 μmol m-2s-1). Almost in all the studied taxa, transpiration and stomatal conductance followed similar trends and reached the maximal
peaks at the same PAR value. The range of breakeven leaf temperature was almost the same in both the families (34-36°C in
Avicenniaceae and 33.5-36.3°C in Rhizophoraceae), beyond which assimilation rate declined. 相似文献
77.
78.
Padmaja N. Kulkarni A. Huntley Blair Tarunendu Ghose Molly Mammen 《Cancer immunology, immunotherapy : CII》1985,19(3):211-214
Summary Methotrexate (MTX) was first conjugated to antibovine serum albumin IgG (antiBSA) or its F(ab)2 fragment to define conditions for retention of drug and antibody activity. With identical drug: protein molar ratios, incorporation in the F(ab)2 fragment was lower than in intact antiBSA, an observation consistent with analysis of the number of lysine residues (22 in F(ab)2 compared to 40 in antiBSA). In either case, up to approximately 10 mol MTX could be incorporated per mol protein, with recovery of 70% of the protein. At an incorporation ratio of 6 mol MTX per mol protein, MTX-antiBSA retained 100% of antibody activity and MTX-F(ab)2antiBSA retained 75%. MTX-antiBSA and MTX-F(ab)2antiBSA were equally potent in vitro inhibitors of dihydrofolate reductase. Conjugates prepared from antiEL4 IgG (AELG) and from F(ab)2AELG significantly increased survival in EL4 lymphoma-bearing mice compared with mice receiving equal amounts (5 mg MTX/kg) of free MTX, MTX linked to the F(ab)2 fragment of normal rabbit IgG, or a simple mixture of MTX and F(ab)2AELG. MTX-AELG at this dose level produced longer survival than MTX-F(ab)2AELG (0.005
2AELG MTX linked to the F(ab)2 fragment of AELG - MTX-F(ab)2antiBSA MTX linked to the F(ab)2 fragment of antiBSA - MTX-F(ab)2NRG MTX linked to the F(ab)2 fragment of NRG - MTX-NRG MTX linked to NRG - NHS N-hydroxysuccinimide - NRG normal rabbit IgG - PBS 0.01 M sodium phosphate (pH 7.1) containing 0.45 M sodium chloride - TAA tumor-associated antigen - t1/2 half-life 相似文献
79.
The cotyledon of the seed of Mirabilis jalapa was found to contain a
-glucan. Methylation, periodate oxidation, and graded and enzymic hydrolysis studies were conducted to elucidate its structure. For every 38
-glucosyl residues therein, 34 are (1→4)- and 3 are (1→3)-linked; the
-glucosyl unit at the branch point is linked through O-1, O-2, and O-4. In some places in the chain, there are at least three (1→3)-linked
-glucosyl residues in a sequence. Both α- and β-
-glucosidic linkages are present in the polysaccharide, the former preponderating. The
-glucan gave with iodine a faint blue color that had λmax 420 nm. 相似文献
80.
Aerobiologia - Bioaerosols have gained importance in atmospheric sciences in the past few decades. Their exposure upsurges the health problems in sensitive population and is also known to... 相似文献