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171.
Reiter LA Subramanyam C Mangual EJ Jones CS Smeets MI Brissette WH McCurdy SP Lira PD Linde RG Li Q Zhang F Antipas AS Blumberg LC Doty JL Driscoll JP Munchhof MJ Ripp SL Shavnya A Shepard RM Sperger D Thomasco LM Trevena KA Wolf-Gouveia LA Zhang L 《Bioorganic & medicinal chemistry letters》2007,17(19):5447-5454
A series of pyrimidine benzamide-based thrombopoietin receptor agonists is described. The lead molecule contains a 2-amino-5-unsubstituted thiazole, a group that has been associated with idiosyncratic toxicity. The potential for metabolic oxidation at C-5 of the thiazole, the likely source of toxic metabolites, was removed by substitution at C-5 or by replacing the thiazole with a thiadiazole. Potency in the series was improved by modifying the substituents on the pyrimidine and/or on the thiazole or thiadiazole pendant aryl ring. In vivo examination revealed that compounds from the series are not highly bioavailable. This is attributed to low solubility and poor permeability. 相似文献
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Chinreddy Subramanyam Reddy Tanushri Kaul Khaled Fathy Abdel Motelb Sonia Khan Sony Jyotsna Bharti Rachana Verma 《Bioinformation》2021,17(8):727
Purple acid phosphatases belong to metallo-phosphatase family. Intracellular phosphatases are crucial for phosphorus (P) distribution in the cell and are highly induced in phosphorus-deprived conditions in the soil. Disparate PAP isoforms exist within discrete subcellular compartments in Setaria italica and their expression in P deprived conditions fosters phosphorus amelioration. We isolated the SiPAP18 gene and developed the homology SiPAP18 protein model based on the crystal structure of the Kidney bean PvPAP (PDB ID: 2QFP) as template (sequence similarity 42.7%) using Modeller 9.12 with adequate validation. Structure model analysis shows the significance of five conserved signatures with seven metal-paired amino acid residues during P-deprivation induced phosphorus amelioration. 相似文献
174.
Ursula Pieper Ranyee Chiang Jennifer J. Seffernick Shoshana D. Brown Margaret E. Glasner Libusha Kelly Narayanan Eswar J. Michael Sauder Jeffrey B. Bonanno Subramanyam Swaminathan Stephen K. Burley Xiaojing Zheng Mark R. Chance Steven C. Almo John A. Gerlt Frank M. Raushel Matthew P. Jacobson Patricia C. Babbitt Andrej Sali 《Journal of structural and functional genomics》2009,10(2):107-125
To study the substrate specificity of enzymes, we use the amidohydrolase and enolase superfamilies as model systems; members
of these superfamilies share a common TIM barrel fold and catalyze a wide range of chemical reactions. Here, we describe a
collaboration between the Enzyme Specificity Consortium (ENSPEC) and the New York SGX Research Center for Structural Genomics
(NYSGXRC) that aims to maximize the structural coverage of the amidohydrolase and enolase superfamilies. Using sequence- and
structure-based protein comparisons, we first selected 535 target proteins from a variety of genomes for high-throughput structure
determination by X-ray crystallography; 63 of these targets were not previously annotated as superfamily members. To date,
20 unique amidohydrolase and 41 unique enolase structures have been determined, increasing the fraction of sequences in the
two superfamilies that can be modeled based on at least 30% sequence identity from 45% to 73%. We present case studies of
proteins related to uronate isomerase (an amidohydrolase superfamily member) and mandelate racemase (an enolase superfamily
member), to illustrate how this structure-focused approach can be used to generate hypotheses about sequence–structure–function
relationships.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
相似文献
Andrej Sali (Corresponding author)Email: URL: http://salilab.org |
175.
Balamurugan B Roshan MN Michael D Ambaree M Divya S Keerthana H Seemanthini M Sekar K 《In silico biology》2006,6(3):229-235
Structure prediction methods aim to identify the relationship between the amino acid sequence of an unknown protein and information comprised in databases of known protein structures. Towards this end, we created a database by combining the amino acid sequences and the corresponding three-dimensional atomic coordinates for all the 25% non-redundant protein chains available in the Protein Data Bank. It contains information about the peptide fragments that are 5 to 10 residues long. In addition, options are provided for the users to visualize the individual motifs and the superposed fragments in the client machine. Further, useful functionalities areprovided to look for similar sequence motifs in all the sequence databases like PDB, 90% non-redundant protein chains, Genome database, PIR and Swiss-Prot. The database is being updated at regular intervals and the same can be accessed over the World Wide Web interface at the following URL: http://pranag.physics.iisc.ernet.in/sms/. 相似文献
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Ashish Mishra Ippala Janardhan Reddy Paluru Subramanyam Parameswara Gupta Sukanta Mondal 《Animal biotechnology》2017,28(1):18-25
The present study was to find out the expression pattern and relative expression level of apoptotic (Bcl2, Bax, Casp3, and PCNA) and antioxidant enzyme [(GPx, Cu/Zn-SOD (SOD1) and Mn-SOD (SOD2)] genes in sheep oocytes and developing embryos produced in vitro by conventional RT-PCR and real time qPCR, respectively. Different developmental stages of embryos were produced in vitro from oocytes collected from local slaughter house ovaries. RT-PCR amplicons showed expression of Bcl2 and PCNA in all stages except at morula. In contrast Bax and Casp3 were expressed in all stages. GPx and SOD1 were expressed in all stages but SOD2 was not expressed in 8–16 cells, although expressed in the remaining stages. The qPCR analysis reflected that Bcl2 expression was significantly (P < 0.05) downregulated in morula and maximum upregulated expression was observed in in vitro matured oocytes. Higher upregulated expression (P < 0.05) of Bax was in morula and downregulated expression was at 2-4 cells. Casp3 was significantly upregulated at 8–16 cells and downregulated in in vitro matured oocyte. PCNA expression was highest at blastocyst and least expression was at morula. GPx was expressed significantly highest in matured oocytes and least expression was at zygote. SOD1 was expressed significantly highest at 8–16 cells and least expression was at zygote. Expression of SOD2 was least among all the antioxidant enzymes but significantly higher expression of SOD2 was in immature oocyte; however, least expression was at 8–16 cells. It can be concluded from the study that the sheep embryos produced in vitro are highly sensitive to culture condition, which alters the expression level of apoptotic and antioxidant enzyme genes. 相似文献
180.
Role of colour and volatile in foraging behaviour of honeybee Apis cerana on Jacquemontia pentanthos
Floral visual and olfactory cues guide the insect visitors to the source of reward. This work addresses one such interaction between honeybee Apis cerana and a garden climber Jacquemontia pentanthos. Field studies have indicated that A. cerana showed preference to J. pentanthos over the other flowering plants during its visits for foraging. The objectives of the work is to understand the role of colour and scent in the attraction of Apis cerana to the host plant. Bioassays performed emphasized the involvement of colour and volatiles for the visits of A. cerana. Petals show high reflectance to ultraviolet light with ultraviolet absorbing regions in the centre which serve as a nectar guide. Gas chromatography linked electroanntenogram detector (GC-EAD) showed antennal response to the floral volatile of J. pentanthos identified as sesquiterpene β-caryophyllene. Behavioural studies have shown similar preference to β- caryophyllene as that of α-humulene. Our studies suggest an interplay of colour and volatiles cues for A. cerana visitation to Jacquemontia flowers and these findings are further supported by behavioural studies on.A. cerana. 相似文献