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241.
Rajasekaran Ekambaram Akila Kannaiyan Vijayasarathy Marimuthu Vinobha Chinnaiah Swaminathan Senthil Renganathan Ananda Gopu Perumal 《Bioinformation》2014,10(3):138-143
Spatial arrangement of carbon in protein structure is analyzed here. Particularly, the carbon fractions around individual atoms are
compared. It is hoped that it follows the principle of 31.45% carbon around individual atoms. The results reveal that globular
protein''s atoms follow this principle. A comparative study on monomer versus dimer reveal that carbon is better distributed in
dimeric form than in its monomeric form. Similar study on solid versus liquid structures reveals that the liquid (NMR) structure
has better carbon distribution over the corresponding solid (X-Ray) structure. The carbon fraction distributions in fiber and toxin
protein are compared. Fiber proteins follow the principle of carbon fraction distribution. At the same time it has another broad
spectrum of carbon distribution than in globular proteins. The toxin protein follows an abnormal carbon fraction distribution. The
carbon fraction distribution plays an important role in deciding the structure and shape of proteins. It is hoped to help in
understanding the protein folding and function. 相似文献
242.
Monique A. Surette Antony V. Sturz Rajasekaran R. Lada Jerzy Nowak 《Plant and Soil》2003,253(2):381-390
A survey of endophytic bacteria colonizing roots of processing carrots (Daucus carota) was performed with two high-yielding cultivars (Carochoice, Red Core Chantenay) grown at two locations (Canning, Great Village) in Nova Scotia. Most bacterial endophyte colony-forming units (CFU) were recovered from the carrot crown tissues (96%) compared to the periderm and metaxylem tissues of carrot storage tissues irrespective of the cultivars and field locations. Greater population densities of endophytic bacteria were recovered from the crowns of Red Core Chantenay (5.75 × 105 CFU/g FW in Great Village; 3.0 × 105 CFU/g FW in Canning) cultivar, which accounted for 78% of all of CFU recovered compared to cv. Carochoice. Independent of the cultivars, more endophytes were recovered from the carrots produced in Great Village compared to the ones grown in Canning (62 vs. 38%, respectively). Of 360 isolates examined, 28 bacterial genera were identified, of which, Pseudomonas, Staphylococcus, and Agrobacterium were the most common (31, 7 and 7%, respectively). Diversity indices showed no significant differences between the two locations. A bioassay using selected strains of bacteria was performed on 4 week-old carrot (cv. Bergen) and potato (Solanum tuberosum cv. Atlantic) plantlets. In carrots, 83% of the bacterial strains tested were found to be plant growth promoting, 10% remained plant growth neutral and 7% inhibited plant growth. In contrast, in the potato bioassay 38% remained growth neutral, 33% promoted and 29% inhibited plant growth. 相似文献
243.
244.
Gajendran Nithya Rajasekaran Santhanasabapathy Manickam Kalappan Vanitha Pandi Anandakumar Dhanapalan Sakthisekaran 《Journal of biochemical and molecular toxicology》2023,37(1):e23230
Several studies have suggested that increased consumption of phytochemicals is a comparatively easy and practical strategy to significantly decrease the incidence of cancer. In the present study, we have reported the protective effect of a natural compound, thymoquinone (TQ) against benzo(a)pyrene (B(a)P)-induced lung carcinogenesis in Swiss albino mice. B(a)P (50 mg/kg body weight) was administered twice weekly for four successive weeks and left until 20 weeks to induce lung cancer in mice. TQ (20 mg/kg body weight) was given orally as a pretreatment and posttreatment drug to determine its chemopreventive and therapeutic effects. B(a)P-induced lung cancer-bearing animals displayed cachexia-like symptoms along with an abnormal increase in lung weight and the activities of marker enzymes adenosine deaminase, aryl hydrocarbon hydroxylase, gamma-glutamyl transpeptidase, 5′-nucleotidase and lactate dehydrogenase; tumor marker carcinoembryonic antigen levels. Furthermore, B(a)P-induced animals showed elevated levels of lipid peroxides with subsequent depletion in the antioxidant status and histological aberrations. These anomalies were accompanied by increased expressions of proliferating cell nuclear antigen and cyclin D1 in the lung sections derived from B(a)P-induced animals. On TQ treatment, all the above alterations were returned to near normalcy. Furthermore, TQ administration in B(a)P-induced animals downregulated phosphatidylinositol 3-kinase/protein kinase B signaling pathway and induced apoptosis as evidenced by a decrease in cytochrome c, proapoptotic Bax, caspase-3, and p53 with a parallel increase in antiapoptotic Bcl-2. Our present results demonstrate the potential effectiveness of TQ as an antioxidant, antiproliferative, and apoptotic agent against B(a)P-induced experimental lung tumorigenesis. 相似文献
245.
Protein aggregation is a hallmark of various neurodegenerative disorders, such as amyotrophic lateral sclerosis (ALS) in humans. Mutations in Cu/Zn superoxide dismutase (SOD1) protein were found to be a prominent cause behind the majority of the familial ALS cases with abnormal protein aggregates. Herein, we report the biophysical characterization of the beneficial mutation C111S that stabilizes the SOD1 harboring A4V mutation, one of the most lethal diseases causing mutant that leads to protein destabilization and aggregation. In this study, we utilized discrete molecular dynamics (DMD) simulations, which stipulated an outlook over the systematic action of C111S mutation in the A4V mutant that stabilizes the protein and impedes the formation of protein aggregation. Herewith, the findings from our study manifested that the mutation of C111S in SOD1 could aid in regaining the protein structural conformations that protect against the formation of toxic aggregates, thereby hindering the disease pathogenicity subtly. Hence, our study provides a feasible pharmaceutical strategy in developing the treatment for incurable ALS affecting the mankind. 相似文献
246.
The EfeUOB system of Escherichia coli is a tripartite, low pH, ferrous iron transporter. It resembles the high-affinity iron transporter (Ftr1p-Fet3p) of yeast
in that EfeU is homologous to Ftr1p, an integral-membrane iron-permease. However, EfeUOB lacks an equivalent of the Fet3p
component—the multicopper oxidase with three cupredoxin-like domains. EfeO and EfeB are periplasmic but their precise roles
are unclear. EfeO consists primarily of a C-terminal peptidase-M75 domain with a conserved ‘HxxE’ motif potentially involved
in metal binding. The smaller N-terminal domain (EfeO-N) is predicted to be cupredoxin (Cup) like, suggesting a previously
unrecognised similarity between EfeO and Fet3p. Our structural modelling of the E. coli EfeO Cup domain identifies two potential metal-binding sites. Site I is predicted to bind Cu2+ using three conserved residues (C41 and 103, and E66) and M101. Of these, only one (C103) is conserved in classical cupredoxins
where it also acts as a Cu ligand. Site II most probably binds Fe3+ and consists of four well conserved surface Glu residues. Phylogenetic analysis indicates that the EfeO-Cup domains form
a novel Cup family, designated the ‘EfeO-Cup’ family. Structural modelling of two other representative EfeO-Cup domains indicates
that different subfamilies employ distinct ligand sets at their proposed metal-binding sites. The ~100 efeO homologues in the bacterial sequence databases are all associated with various iron-transport related genes indicating a
common role for EfeO-Cup proteins in iron transport, supporting a new copper-iron connection in biology. 相似文献
247.
R K Varma M Rajasekaran A Y Junnarkar P P Singh A Krishnamurthy G S Thapar M R Marathe 《Indian journal of experimental biology》1991,29(1):91-93
IDPH-791, a novel centrally acting muscle relaxant, in doses up to 500 mg/kg (po) for 14 days did not result in any appreciable adverse effect on body weight gain, food or water consumption including biochemical and haematologica parameters in rats. Variations observed in the biochemistry and haematology were either comparable to controls or were within normal limits. 相似文献
248.
Veerasamy Jayaraj Ramamoorthi Suhanya Marimuthu Vijayasarathy Perumal Anandagopu Ekambaram Rajasekaran 《Bioinformation》2009,3(9):409-412
Large Hydrophobic Residues (LHR) such as phenylalanine, isoleucine, leucine, methionine and valine play an important role
in protein structure and activity. We describe the role of LHR in complete set of protein sequences in 15 different species.
That is the distribution of LHR in different proteins of different species is reported. It is observed that the proteins prefer to
have 27% of large hydrophobic residues in total and all along the sequence. It is also observed that proteins accumulate more
LHR in its active sites. A window analysis on these protein sequences shows that the 27% of LHR is more frequent at
window length of 45 amino acids. The influenza virus and P. falciparum show a random distribution of LHR in its proteins
compared to other model organisms. 相似文献
249.
250.
Jay Vyas Ronald J Nowling Thomas Meusburger David Sargeant Krishna Kadaveru Michael R Gryk Vamsi Kundeti Sanguthevar Rajasekaran Martin R Schiller 《BMC bioinformatics》2010,11(1):328