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91.
Vipin K. Paliwal Krishan K. Kohli Mridula Sharma Ravindra Nath 《Molecular and cellular biochemistry》1986,71(2):139-147
Metallothionein (MT) a low molecular weight, Cd-binding, cysteine rich, cytosolic protein has been isolated, purified and characterized from cadmium exposed Rhesus monkeys maintained on protein calorie malnourished (PCM) diet. Metallothionein was resolved into three isoforms i.e. MTa, MTb and MTVc. The ratio of Cd, Zn and Cu varied in these isometallothioneins. MTc was the major isometallothionein. UV Spectra of MTc revealed the presence of mercaptide bonds and absence of aromatic amino acids. These observations were further confirmed by amino acid analysis of MTc which demonstrated high cysteine content (22.6) followed by serine, glycine and lysine. The molecular weight of MTc as determined by gel filtration and amino acid analysis was 13000 and 6398 daltons respectively. This demonstrates that MTc is a non-globular ellipsoid polypeptide. MTc showed a unique property of binding selenium. Monkey liver metallothionein was immunologically identical with human metallothionein. All the characteristics of MTc obtained in the present study reveal a similarity between monkey and human metallothionein probably due to closer phylogenetic relationship between the two species. 相似文献
92.
93.
94.
The Cyt f and P700 contents in leaves of three Sorghum, varietieswere measured, in relation to their carbon assimilation, underdifferent light intensities during growth. At the maximum irradiationused (1,800 µE m2 s1) the ratio of P700to Cyt f was close to unity, whereas under low irradiation (450µE m2 s1) the ratio of P700 to Cyt f rangedfrom two to three. A strikingly positive correlation existedbetween the P700 contents of the leaves and their rates of carbondioxide fixation, dry matter production and Cyt f contents,only when the plants were grown under high light intensities.The P700 content of the leaves in plants grown under low irradiationwas unrelated to the contents of Cyt f. Thus, at a high lightintensity there is a close relationship between the Cyt f andP700 levels, but at low intensities the amounts of electroncarriers and the reaction centre are independent. (Received March 7, 1983; Accepted August 24, 1983) 相似文献
95.
Sanjib Das Robindra N. Baruah Ram P. Sharma Jogendra N. Baruah Palaniappan Kulanthaivel Werner Herz 《Phytochemistry》1983,22(9):1989-1991
Cynaropicrin, 11βH-11,13-dihydrodesacylcynaropicrin, aguerins A and B, isoamberboin and the new guaianolides saussureolide and 11βH-11,13-dihydrodesacylcynaropicrin 8-β-d-glucoside were isolated from Saussurea affinis. 相似文献
96.
M. Islam Khan M. K. Mathew T. Mazumdar D. Pain N. Surolia M. K. Das P. Balaram A. Surolia 《Journal of biosciences》1983,5(1):31-39
The binding ofRicinus communis agglutinin andAbrus agglutinin to 4-methylumbelliferyl β-D-galactopyranoside was studied by equilibrium dialysis, fluo-rescence quenching and fluorescence polarization. The number of binding sites and the association constant value obtained by fluorescence polarization for bothRicinus communis agglutinin andAbrus agglutinin are in close agreement with those obtained by the other methods. This indicates the potential of ligand-fluorescence polarization measurements in the investigation of lectin-sugar interactions. 相似文献
97.
In vitro DNA:DNA hybridizations and hydroxyapatite thermal chromatography were employed to help identify the species ancestral to the B genome of the polyploid wheats. We hybridized 3H-Triticum aestivum DNA to the unlabeled DNAs of T. urartu, T. speltoides, T. sharonensis, T. bicorne, T. longissimum, and T. searsii, 3H-Labeled DNA of T. urartu was hybridized with the DNA of a synthetic tetraploid. AADD. The heteroduplex thermal stabilities indicated that T. searsii was most closely related to T. aestivum (ABD) and that the genome of T. urartu was more closely related to the A genome than the B genome. The degree of reassociation which may have occurred between the six diploid species and the D genome of T. aestivum was evaluated by hybridizing 3H-T. tauschii DNA with the DNAs of the diploids. The results indicated that T. urartu had the least sequence homology to T. tauschii, the D-genome donor lending additional support to the conclusion that T. urartu is related to the A genome. Thus, it is highly probable that T. searsii is the B-genome donor to the polyploid wheats or a major chromosome donor if the B genome is, in fact, polyphyletic in origin. 相似文献
98.
Satya Prakash Srivastava Mukul Das Prahlad K. Seth 《Chemico-biological interactions》1983,45(3):373-380
Lipid peroxidation, glutathione level and activity of glutathione-S-transferase were studied in liver and brain of rats 4 and 3 h after a single i.p. administration of 0, 25, 75, 100 mg/kg acrylamide or 0, 50, 100, 200, 600 mg/kg styrene, respectively. In liver both acrylamide and styrene caused an increase in lipid peroxidation and decrease in glutathione contents and activity of glutathione-S-transferase in a dose dependent manner, while in brain only acrylamide produced a decrease in glutathione content. The decrease in glutathione content was not always associated with increase of lipid peroxidation. The enhancement of lipid peroxidation occurred only when glutathione contents were depleted to certain critical levels. No effect of acrylamide or styrene was seen on lipid peroxidation under in vitro conditions. The addition of glutathione in the incubation mixture significantly inhibited the rate of lipid peroxidation of liver homogenates of acrylamide and styrene treated animals.The results suggest that enhancement of lipid peroxidation in liver on exposure to acrylamide or styrene is a consequence of depletion of glutathione to certain critical levels. The inhibition of glutathione-S-transferase activity by acrylamide and styrene suggests that detoxication of these neurotoxic compounds could be suppressed following acute exposure. 相似文献
99.
Summary In the present study attempts have been made to elucidate the composition and physiological actions of root exudates from
CB-1 Rupsail and the mixed population of these two varieties. The chemical nature of the different components of root exudates
was studied by means of paper chromatography, bioassay and other biochemical procedures. It was noted that exudates from CB-1
and Rupsail seedlings inhibited root/shoot growth of test seedlings of both varieties. But when these two varieties were grown
together root/shoot growth of both varieties were markedly promoted. Both qualitative and quantitative differences in amino
acids, carbohydrates and growth substances contents of root exudates of individual and mixed population of rice varieties
were noted. 相似文献
100.
I Das 《Canadian journal of biochemistry》1973,51(5):637-641