Identity Elements of Archaeal tRNA

Features unique to a transfer-RNA are recognized by the corresponding tRNA-synthetase. Keeping this in view we isolate the discriminating features of all archaeal tRNA. These are our identity elements. Further, we investigate tRNA-characteristics that delineate the different orders of archaea

Severe Oleander Poisoning Presenting with Hyperkalaemia and Unusual Electrocardiographic Changes

Background: Hyperkalaemia in oleander (Nerium oleander) poisoning has been associated with a poor prognosis. Different electrocardiographic (ECG) presentations are possible because of vagotonia and hyperkalaemia. Methods/Results: We report a series of three cases of oleander poisoning in which ECG showed unusual hyperkalaemia features, such as bradyarrhythmia, sinoatrial block, atrioventricular block and junctional rhythm. Conclusions: If arterial blood gas analysis or laboratory values indicate hyperkalaemia in oleander poisoning, the hyperkalaemia should be treated immediately, even if the ECG does not show typical hyperkalaemia features

tRNA-isoleucine-tryptophan Composite Gene

Transfer-RNA genes in archaea often have introns intervening between exon sequences. The structural motif at the boundary between exon and intron is the bulge-helix-bulge. Computational investigations of these boundary structures in H. marismortui lead us to propose that tRNA-isoleucine and tRNA-tryptophan genes are co-located. Precise insilico identification of the splice-sites on the bulges at the exon-intron boundaries conduce us to infer that a single intron-containing composite tRNA-gene can give rise to more than one gene produc.Comment: 15 pages, 3 figure

Pressures in Archaeal Protein Coding Genes: A Comparative Study

Our studies on the bases of codons from 11 completely sequenced archaeal genomes show that, as we move from GC-rich to AT-rich protein-coding gene-containing species, the differences between G and C and between A and T, the purine load (AG content), and also the overall persistence (i.e. the tendency of a base to be followed by the same base) within codons, all increase almost simultaneously, although the extent of increase is different over the three positions within codons. These findings suggest that the deviations from the second parity rule (through the increasing differences between complementary base contents) and the increasing purine load hinder the chance of formation of the intra-strand Watson–Crick base-paired secondary structures in mRNAs (synonymous with the protein-coding genes we dealt with), thereby increasing the translational efficiency. We hypothesize that the ATrich protein-coding gene-containing archaeal species might have better translational efficiency than their GC-rich counterparts

On the Appearance of a Cooper Minimum in the Photoionization Cross Sections of the Plasma-Embedded Li Atom

The plasma screening effect is found to uncover a Cooper minimum in the photoionization cross sections from the ground state of the Li atom embedded in Debye plasma environment. The variation of the location of this minimum with Debye screening length is discussed and analyzed in terms of the instability of the ground state

Algorithm for pattern recognition in nano-sized archaea

Hidden patterns abound in genome sequences. Sophisticated mathematical algorithms spot them. As of now, several powerful tools exist for identification of transfer-RNA genes from genomes. These sometimes fail to identify when introns are at noncanonical sites. We discuss our approach to this problem of identification and apply it to the genome of Nanoarchaeum equitans. Using our algorithm, we identify the four tRNA genes that were missed by the present standard tRNA search programs in N. equitans. The recent split-tRNA hypothesis [Nature 433, 537 (2005)] identified the missing ones. However, our solutions are different. We argue the case in favour of our solutions.Author Affiliation: Jayprokas Chakrabarti, Satyabrata Sahoo, Bibekanand Mallick, Smarajit Das and Zhumur Ghosh 1.Computational Biology Group (CBG), Department of Theoretical Physics, Indian Association for the Cultivation of Science, Kolkata-700 032, India E-mail : [email protected] Biology Group (CBG), Department of Theoretical Physics, Indian Association for the Cultivation of Science, Kolkata-700 032, Indi