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991.
Sanjukta Mukherjee Chikara Dohno Kaori Asano Kazuhiko Nakatani 《Nucleic acids research》2016,44(15):7090-7099
A newly designed cyclic bis-naphthyridine carbamate dimer CMBL4 with a limited conformational flexibility was synthesized and characterized. Absorption spectra revealed that two naphthyridines in CMBL4 were stacked on each other in aqueous solutions. The most efficient binding of CMBL4 to DNA was observed for the sequence 5′-T-3′/5′-GG-3′ (T/GG) with the formation of a 1:1 complex, which is one of possible structural elements involved in the higher order structures of (TGG)n repeat DNA triggering the genome microdeletion. Surface plasmon resonance assay also showed the binding of CMBL4 with TGG repeat DNA. Potassium permanganate oxidation studies of CMBL4-bound duplex containing the T/GG site showed that the CMBL4-binding accelerated the oxidation of thymine at that site, which suggests the flipping out of the thymine base from a π-stack. Preferential binding was observed for CMBL4 compared with its acyclic variants, which suggests the marked significance of the macrocyclic structure for the recognition of the T/GG site. 相似文献
992.
Ananya Marik Haraprasad Naiya Madhumanti Das Gairik Mukherjee Soumalee Basu Chinmay Saha Rajdeep Chowdhury Kankan Bhattacharyya Anindita Seal 《Plant molecular biology》2016,92(4-5):519-537
Natural resistance associated macrophage proteins (NRAMPs) are evolutionarily conserved metal transporters involved in the transport of essential and nonessential metals in plants. Fifty protein interactors of a Brassica juncea NRAMP protein was identified by a Split-Ubiquitin Yeast-Two-Hybrid screen. The interactors were predicted to function as components of stress response, signaling, development, RNA binding and processing. BjNRAMP4.1 interactors were particularly enriched in proteins taking part in photosynthetic or light regulated processes, or proteins predicted to be localized in plastid/chloroplast. Further, many interactors also had a suggested role in cellular redox regulation. Among these, the interaction of a photosynthesis-related thioredoxin, homologous to Arabidopsis HCF164 (High-chlorophyll fluorescence164) was studied in detail. Homology modeling of BjNRAMP4.1 suggested that it could be redox regulated by BjHCF164. In yeast, the interaction between the two proteins was found to increase in response to metal deficiency; Mn excess and exogenous thiol. Excess Mn also increased the interaction in planta and led to greater accumulation of the complex at the root apoplast. Network analysis of Arabidopsis homologs of BjNRAMP4.1 interactors showed enrichment of many protein components, central to chloroplastic/cellular ROS signaling. BjNRAMP4.1 interacted with BjHCF164 at the root membrane and also in the chloroplast in accordance with its proposed function related to photosynthesis, indicating that this interaction occurred at different sub-cellular locations depending on the tissue. This may serve as a link between metal homeostasis and chloroplastic/cellular ROS through protein–protein interaction. 相似文献
993.
Dola Mukherjee Deeya Saha Debarun Acharya Ashutosh Mukherjee Sandip Chakraborty Tapash Chandra Ghosh 《Genomics》2018,110(5):310-317
In Arabidopsis thaliana, primary metabolic genes (PMGs) are more evolutionarily conserved and intron-rich than secondary metabolic genes. We observed that PMGs are more primitive and pan-taxonomically persistent as compared to secondary (SMGs) and non-metabolic genes (NMGs). This difference in primitiveness and persistence is primarily correlated with intron number and is independent of gene expression level. We propose a twofold explanation behind higher intron enrichment in PMGs. Firstly, introns might increase protein versatility amongst PMGs through alternative splicing, providing selective advantage of PMGs and making them more persistent across diverse plant taxa. Also, multifunctional PMGs may acquire functional domains by increasing the intronic burden. Additionally, single nucleotide polymorphisms (SNPs) accumulate at a higher rate in introns as compared to exons. Moreover, a strong negative correlation between cumulative exonic SNPs density and intron number indicates that introns may protect the exonic regions against the deleterious effect of these mutations, making them more conserved. 相似文献
994.
995.
A P Reddy B N Mukherjee M Vijayakumar K C Malhotra 《American journal of physical anthropology》1986,71(1):89-94
Red cell hemolysates from 1,004 persons belonging to 14 population groups drawn from four South Indian states, Andhra Pradesh, Tamil Nadu, Karnataka, and Kerala, were tested for PGM1 subtypes. The groups are characterized by a high frequency of phenotype 1+1+ (range 36.98-71.64%) and the allele 1+ (range 60-79%). The groups exhibit marked heterogeneity for PGM1 locus. The results show a clear demarcation between tribes and Brahmin groups. 相似文献
996.
Subir K. NagDas Shyamali Mukherjee Barsanjit Mazumder Parimal C. Sen 《Molecular and cellular biochemistry》1988,79(2):161-169
Rat testicular microsomal membrane fraction contains both Mg+2-dependent and Mg+2-independent Ca+2-ATPase activity. The latter activity is about two times higher than the former. Calcium ion required for maximum activation
of Mg+2-independent Ca+2-ATPase in 3.0 mM, whereas for the dependent one it is 2.5 mM. Both the enzymes are resistant to cold shock upto seven days.
Histidine and imidazole buffers are found to be the most suitable for dependent and independent enzyme activities, respectively.
The pH optima for dependent one is 7.5, whereas for the independent one it is 8.5. Temperature optima for the former is 37°C
and for latter one it is 40°C. Among all the nuclestides tested, ATP is found to be the best substrate for both the enzymes.
The optimum concentration of ATP for dependent and independent enzyme activities are 3.0 mM and 1.5 mM respectively. Divalent
metal ions like Zn+2, Ba+2 and Mn+2 have been found to inhibit Mg+2-dependent Ca+2-ATPase activity whereas Mg+2-independent Ca+2-ATPase activity is inhibited by the divalent ions except zinc which is found to stimulate the enzyme activity. Both the enzymes
are inhibited by vanadata, EDTA and EGTA. I50, for vanadate is 0.05 and 0.125 mM for dependent and independent activities, respectively. Sulfhydral groups modifying agents
e.g., NEM, DTNB and chlorpromazine are found to affect the enzyme activities in different ways. Thus NEM and chlorpromazine
are found to inhibit and DTNB stimulate the enzyme activities in both the cases. 相似文献
997.
Leishmania donovani: role of microviscosity of macrophage membrane in the process of parasite attachment and internalization 总被引:2,自引:0,他引:2
Host macrophage infection by the parasite Leishmania donovani is heterogeneous, but it is not clear which factors are responsible for parasite recognition within the macrophages. One possible factor may be the alteration of the microviscosity of the macrophage membrane. This in turn may affect receptor expression and hence parasite infection. In this paper we describe alteration of the lipid composition and hence the microviscosity of the macrophage membrane in a controlled manner using liposome fusion technique. At a higher macrophage membrane microviscosity a larger number of parasites have been found to adhere to the macrophage surface. However, the proportion of parasites finally internalized when compared to parasites adhering to macrophages is inversely correlated with the artificially altered macrophage membrane microviscosity. The process of endocytosis has been examined in both native and lipid modified macrophages in the presence of several sugar antagonists. The results indicate (i) glucose and mannose are specifically involved in the binding process, and (ii) the microviscosity has a key role in controlling the macrophage parasite interaction. The results obtained so far support a model of endocytosis where expression of the receptor is a critical initial process dependent on the microviscosity of the membrane. 相似文献
998.
The peroxidase activity of mouse submaxillary gland was found to be elevated by about 128% at 22 hr. after the administration of reserpine (0.5 mg/kg). This effect of reserpine was observed in rat also. Neither pretreatment with 6-hydroxy dopamine (6-OH dopamine) nor surgical sympathetic denervation could abolish the increase of the peroxidase activity elicited by reserpine. Also, treatment with propranolol, dibenamine or atropine sulfate failed to reverse the effect of reserpine. These results suggest that neither catecholamine nor acetyl choline is involved in this reserpine action. 相似文献
999.
L T Boni J S Hah S W Hui P Mukherjee J T Ho C Y Jung 《Biochimica et biophysica acta》1984,775(3):409-418
Various aspects of the interaction between the fusogen, poly(ethylene glycol) and phospholipids were examined. The aggregation and fusion of small unilamellar vesicles of egg phosphatidylcholine (PC), bovine brain phosphatidylserine (PS) and dimyristoylphosphatidylcholine (DMPC) were studied by dynamic light scattering, electron microscopy and NMR. The fusion efficiency of Dextran, glycerol, sucrose and poly(ethylene glycol) of different molecular weights were compared. Lower molecular weight poly(ethylene glycol) are less efficient with respect to both aggregation and fusion. The purity of poly(ethylene glycol) does not affect its fusion efficiency. Dehydrating agents, such as Dextran, glycerol and sucrose, do not induce fusion. 31P-NMR results revealed a restriction in the phospholipid motion by poly(ethylene glycol) greater than that by glycerol and Dextran of similar viscosity and dehydrating capacity. This may be associated with the binding of poly(ethylene glycol) to egg PC, with a binding capacity of 1 mol of poly(ethylene glycol) to 12 mol of lipid. Fusion is greatly enhanced below the phase transition for DMPC, with extensive fusion occurring below 6% poly(ethylene glycol). Fusion of PS small unilamellar vesicles depends critically on the presence of cations. Large unilamellar vesicles were found to fuse less readily than small unilamellar vesicles. The results suggest that defects in the bilayer plays an important role in membrane fusion, and the 'rigidization' of the phospholipid molecules facilitates fusion possibly through the creation of defects along domain boundaries. Vesicle aggregation caused by dehydration and surface charge neutralization is a necessary but not a sufficient condition for fusion. 相似文献
1000.