NOPR Collection:

Identification of human proteins using the linguist's tools

2013-07-25T16:34:57Z

Title: Identification of human proteins using the linguist's tools Authors: Chattopadhyay, S; Chakrabarti, J; Bandyopadhyay, D; Som, A Abstract: The symbolic sequences of the exons that make human proteins are subjected to methods of statistical linguistics. The ideas developed for the natural languages by G. K. Zipf, when applied to these sequences, show significant promise. In particular, we argue, the Zipf's exponent differentiates, and hence, identifies disparate human sequences. Page(s): 124-127

Quantitative structure activity relationship (QSAR) studies of some substituted benzenesulphonyl glutamines as tumour suppressors

2013-07-17T16:35:49Z

Title: Quantitative structure activity relationship (QSAR) studies of some substituted benzenesulphonyl glutamines as tumour suppressors Authors: Srikanth, K; Kumar, Ch. Anil; Goswami, Diptendu; De, A U; Jha, Tarun Abstract: As a part of a composite programme of rational drug design (RDD)¹, we had synthesized some substituted benzene sulphonyl glutamines and evaluated their inhibitory activities against Ehrlich Ascites Carcinoma (EAC) cell line in Swiss albino mice. Quantitative structure activity relationship (QSAR) studies of these inhibitory activities using Fujita-Ban model as well as Modified Hansch-Fujita model gave excellent correlations (correlation coefficient r = 0.89 and 0.82 respectively). These results could be useful in designing 'lead' compound with potent inhibitory activity on DNA and RNA synthesis and tumour development. Page(s): 120-123

Wobble base-pairing in codon-anticodon interactions: A theoretical modelling study

2013-07-16T16:35:42Z

Title: Wobble base-pairing in codon-anticodon interactions: A theoretical modelling study Authors: Mangang, S Ulen; Lyngdoh, R H Duncan Abstract: The Crick wobble hypothesis attributes the phenomenon of codon degeneracy to a certain impreciseness of pairing between the third base of the codon and the first base of the anticodon. This theoretical study investigates the pairing properties of some wobble bases, including both, observed and unobserved pairs. Some wobble base-pairs are predicted to follow the Watson-Crick pairs in configuration and pairing facility, while others deviate from this norm. The observed U:V pair is unique in that a pairing configuration may be suggested for it wherein the hydrogen-bonding involves the exocyclic 5- carboxy methoxy group of V. By comparing the theoretical data on the configurations of these pairs with the evidence for their existence/non-existence in nature, some guidelines emerge for differentiating between observed and unobserved base pairs on the basis of the pairing configuration. Page(s): 115-119

Neural network prediction of 310-helices in proteins

2013-07-23T16:35:32Z

Title: Neural network prediction of 310-helices in proteins Authors: Pal, Lipika; Basu, Gautam Abstract: Secondary structure prediction from the primary sequence of a protein is fundamental to understanding its structure and folding properties. Although several prediction methodologies are in vogue, their performances are far from being completely satisfactory. Among these, non-linear neural networks have been shown to be relatively effective, especially for predicting -turns, where dominant interactions are local, arising from four sequence-contiguous residues. Most 3₁₀-helices in proteins arc also short comprising of three sequence-contiguous residues and two capping residues. In order to understand the extent of local interactions in these 3₁₀-helices, we have applied a neural network model with varying window size to predict 3₁₀-helices in proteins. We found the prediction accuracy of 3₁₀-helices (~ 14%), as judged by the Matthew's Correlation Coefficient, to be less than that of β-turns (~ 20%). The optimal window size for the prediction of 3₁₀-helices was about 9 residues. The significance and implications of these results in understanding the occurrence of 3₁₀-helices and preferences of amino acid residues in 3₁₀-helices are discussed. Page(s): 107-114