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排序方式: 共有333条查询结果,搜索用时 15 毫秒
31.
Lingaiah K Parshwanath BA Mysore SR Krishnamurthy B Ramachandra NB 《Indian journal of human genetics》2010,16(3):166-168
Birth defects have become the important cause of mortality and morbidity in the perinatal period. Congenital heart disease (CHD) is the most common birth defect which includes the varying forms of cardiac abnormalities and occurs with an incidence of 1 per 100 live births. In most of the cases, CHD is an isolated malformation, but about 33% have associated anomalies. Ambiguous genitalia are one such rare anomaly that is associated with CHD among other genital abnormalities. The possible causes for this association could be pseudohermaphroditism, which in turn, may be due to congenital adrenal hyperplasia. The government of any country should consider providing for its people a free prenatal diagnosis for susceptible disorders. 相似文献
32.
Gregory M. Raner Jonathan I. Thompson Alice Haddy Valary Tangham Nicole Bynum G. Ramachandra Reddy David P. Ballou John H. Dawson 《Journal of inorganic biochemistry》2006,100(12):2045
Rapid mixing of substrate-free ferric cytochrome P450BM3–F87G with m-chloroperoxybenzoic acid (mCPBA) resulted in the sequential formation of two high-valent intermediates. The first was spectrally similar to compound I species reported previously for P450CAM and CYP 119 using mCPBA as an oxidant, and it featured a low intensity Soret absorption band characterized by shoulder at 370 nm. This is the first direct observation of a P450 compound I intermediate in a type II P450 enzyme. The second intermediate, which was much more stable at pH values below 7.0, was characterized by an intense Soret absorption peak at 406 nm, similar to that seen with P450CAM [T. Spolitak, J.H. Dawson, D.P. Ballou, J. Biol. Chem. 280 (2005) 20300–20309]. Double mixing experiments in which NADPH was added to the transient 406 nm-absorbing intermediate resulted in rapid regeneration of the resting ferric state, with the flavins of the flavoprotein domain in their reduced state. EPR results were consistent with this stable intermediate species being a cytochrome c peroxidase compound ES-like species containing a protein-based radical, likely localized on a nearby Trp or Tyr residue in the active site. Iodosobenzene, peracetic acid, and sodium m-periodate also generated the intermediate at 406 nm, but not the 370 nm intermediate, indicating a probable kinetic barrier to accumulating compound I in reactions with these oxidants. The P450 ES intermediate has not been previously reported using iodosobenzene or m-periodate as the oxygen donor. 相似文献
33.
Tejesvi MV Mahesh B Nalini MS Prakash HS Kini KR Subbiah V Shetty HS 《Canadian journal of microbiology》2006,52(5):427-435
Endophytic fungi represent an interesting group of microorganisms associated with the healthy tissues of terrestrial plants. They represent a large reservoir of genetic diversity. Fungal endophytes were isolated from the inner bark segments of ethnopharmaceutically important medicinal tree species, namely Terminalia arjuna, Crataeva magna, Azadirachta indica, Holarrhena antidysenterica, Terminalia chebula, and Butea monosperma (11 individual trees), growing in different regions of southern India. Forty-eight fungal species were recovered from 2200 bark segments. Mitosporic fungi represented a major group (61%), with ascomycetes (21%) and sterile mycelia (18%) the next major groups. Species of Fusarium, Pestalotiopsis, Myrothecium, Trichoderma, Verticillium, and Chaetomium were frequently isolated. Exclusive fungal taxa were recovered from five of the six plant species considered for the study of endophytic fungi. Rarefaction indices for species richness indicated the highest expected number of species for bark segments were isolated from T. arjuna and A. indica (20 species each) and from C. magna (18 species). 相似文献
34.
Kaul R Saha P Saradhi M Prasad RL Chatterjee S Ghosh I Tyagi RK Datta K 《The Journal of biological chemistry》2012,287(23):19750-19764
Overexpression of the mature form of hyaluronan-binding protein 1 (HABP1/gC1qR/p32), a ubiquitous multifunctional protein involved in cellular signaling, in normal murine fibroblast cells leads to enhanced generation of reactive oxygen species (ROS), mitochondrial dysfunction, and ultimately apoptosis with the release of cytochrome c. In the present study, human liver cancer cell line HepG2, having high intracellular antioxidant levels was chosen for stable overexpression of HABP1. The stable transformant of HepG2, overexpressing HABP1 does not lead to ROS generation, cellular stress, and apoptosis, rather it induced enhanced cell growth and proliferation over longer periods. Phenotypic changes in the stable transformant were associated with the increased "HA pool," formation of the "HA cable" structure, up-regulation of HA synthase-2, and CD44, a receptor for HA. Enhanced cell survival was further supported by activation of MAP kinase and AKT-mediated cell survival pathways, which leads to an increase in CYCLIN D1 promoter activity. Compared with its parent counterpart HepG2, the stable transformant showed enhanced tumorigenicity as evident by its sustained growth in low serum conditions, formation of the HA cable structure, increased anchorage-independent growth, and cell-cell adhesion. This study suggests that overexpression of HABP1 in HepG2 cells leads to enhanced cell survival and tumorigenicity by activating HA-mediated cell survival pathways. 相似文献
35.
Wienk H Tishchenko E Belardinelli R Tomaselli S Dongre R Spurio R Folkers GE Gualerzi CO Boelens R 《The Journal of biological chemistry》2012,287(14):10922-10932
Bacterial translation initiation factor IF2 promotes ribosomal subunit association, recruitment, and binding of fMet-tRNA to the ribosomal P-site and initiation dipeptide formation. Here, we present the solution structures of GDP-bound and apo-IF2-G2 of Bacillus stearothermophilus and provide evidence that this isolated domain binds the 50 S ribosomal subunit and hydrolyzes GTP. Differences between the free and GDP-bound structures of IF2-G2 suggest that domain reorganization within the G2-G3-C1 regions underlies the different structural requirements of IF2 during the initiation process. However, these structural signals are unlikely forwarded from IF2-G2 to the C-terminal fMet-tRNA binding domain (IF2-C2) because the connected IF2-C1 and IF2-C2 modules show completely independent mobility, indicating that the bacterial interdomain connector lacks the rigidity that was found in the archaeal IF2 homolog aIF5B. 相似文献
36.
Anirban Guha Debashree Sengupta Girish Kumar Rasineni Attipalli Ramachandra Reddy 《Trees - Structure and Function》2012,26(3):903-918
The present study investigated drought-induced responses of non-enzymatic antioxidants in four diverse mulberry genotypes (Morus indica L. S-36, M-5, MR-2 and V-1). Inside the glasshouse, potted plants were subjected to four water regimes for 75 days: (a) control: pots maintained at 100% pot water holding capacity (PC) (b) low water stress: 75% PC (c) medium water stress: 50% PC and (d) high water stress: 25% PC. Photosynthetic leaf gas exchange and non-enzymatic antioxidants including α-tocopherol, ascorbic acid (AA), glutathione, proline and total carotenoids were measured in leaves at regular intervals. Amongst all, V-1 was relatively drought tolerant and showed exceeded accumulation of α-tocopherol and AA-glutathione pool in association with higher carotenoids and proline contents. Susceptible S-36, M-5 and MR-2 could not induce any significant up-regulation in AA-glutathione pool leading to endogenous loss of α-tocopherol and more lipid peroxidation. Reactive oxygen species (ROS) like hydrogen peroxide (H2O2) and superoxide (O2 · ?) showed apparent accumulation in water-stressed leaves and significantly contributed to lipid peroxidation in susceptible genotypes when compared to V-1. Our study demonstrated that proline, AA and glutathione were the major non-enzymatic antioxidants in mulberry with α-tocopherol and carotenoids as good additional indicators for drought stress tolerance. These non-enzymatic antioxidants can cumulatively render effective protection against oxidative damage and can be considered as reliable markers for screening drought-tolerant mulberry genotypes. 相似文献
37.
Ghantasala S Sameer Kumar Abhilash K Venugopal Anita Mahadevan Santosh Renuse H C Harsha Nandini A Sahasrabuddhe Harsh Pawar Rakesh Sharma Praveen Kumar Sudha Rajagopalan Keith Waddell Yarappa L Ramachandra Parthasarathy Satishchandra Raghothama Chaerkady T S Keshava Prasad K Shankar Akhilesh Pandey 《Clinical proteomics》2012,9(1):12
38.
Santosh Kumar Ramachandra Jadhav Krunal Arvind Patel Bhushan Bhalchandra Dholakia Bashir Mohammad Khan 《Bioinformation》2012,8(19):943-949
Medicinal plants are extensively utilized in traditional and herbal medicines, both in India and around the world due to the
presence of diverse low molecular weight natural products such as flavonoids, alkaloids, terpenoids and sterols. Flavonoids which
have health benefits for humans are the large class of phenylpropanoid-derived secondary metabolites and are mostly glycosylated
by UDP-glycosyltransferases (UGTs). Although large numbers of different UGTs are known from higher plants, very few protein
structures have been reported till now. In the present study, the three-dimensional model of flavonoid specific glycosyltransferases
(WsFGT) from Withania somnifera was constructed based on the crystal structure of plant UGTs. The resulted model was assessed
by various tools and the final refined model revealed GT-B type fold. Further, to understand the sugar donors and acceptors
interactions with the active site of WsFGT, docking studies were performed. The amino acids from conserved PSPG box were
interacted with sugar donor while His18, Asp110, Trp352 and Asn353 were important for catalytic function. This structural and
docking information will be useful to understand the glycosylation mechanism of flavonoid glucosides.
Abbreviations
DOPE - Discrete Optimized Potential Energy, PDB - Protein Data Bank, PSPG - Plant Secondary Product Glycosyltransferase, RMSD - Root Mean Squared Deviation, UDP - Uridine diphosphate, UGT - UDP-glycosyltransferases. 相似文献39.
Cholinesterases (ChEs) are classified as either acetylcholinesterase (AChE) or butyrylcholinesterase (BChE) based on their substrate and inhibitor specificity. Organophosphate and carbamate compounds commonly represented by herbicides, pesticides, and nerve gases irreversibly inhibit ChEs. Therefore, exposure to organophosphates and carbamates is normally assessed by measuring ChE activity in blood. There are two approaches for measuring AChE and BChE activity present in whole blood: (1) separating blood into erythrocytes, which contain only AChE, and plasma which contains only BChE, to measure their activity individually, or (2) use a BChE-specific inhibitor to measure the activity of AChE in whole blood. A number of studies have reported the use of different inhibitors for the simultaneous measurement of AChE and BChE activities. However, the inhibitors used for completely inhibiting BChE activity also inhibited AChE activity leading to errors in reported values. The goal of this study was to find the most accurate and simple method for the simultaneous determination of AChE and BChE activity in animal whole blood. Solutions containing human AChE and BChE in various proportions were prepared and AChE and BChE activities were measured using three reported methods. Results demonstrate that ethopropazine and (-) huperzine A appear to be the most specific ChE inhibitors. Preliminary results with human and animal whole blood suggest that 20muM ethopropazine and 500nM (-) huperzine A can be used for measuring AChE and BChE activities across species. 相似文献
40.
D.?SundarEmail author K.V.?Chaitanya P.P.?Jutur A.?Ramachandra ReddyEmail author 《Plant Growth Regulation》2004,44(2):175-181
Two-year-old rubber-producing shrub, guayule (Parthenium argentatum, cv. 11591), was treated with low temperature (15 °C). The leaves were harvested at regular intervals (0, 2, 4 and 6 days) and the contents of protective antioxidants (ascorbic acid, monodehydroascorbate and caroteniods) and antioxidative enzymes (superoxide dismutase, catalase, peroxidases, glutathione reductase and monodehydroascorbate reductase) were determined. Low temperature-induced significant increase in the contents of ascorbic acid, monodehydroascorbate and caroteniods as well as the activities of all antioxidative enzymes. The results show an increase in several components of the antioxidant system in cold-treated guayule plants, which may suggest a role in mitigating an increase in oxidative stress. 相似文献