Download or read book Recognition of TRNA Lys 3 by Human Lysyl tRNA Synthetase and Studies of TRNA Lys 3 Primer Annealing by the HIV 1 Nucleocapsid Protein written by Timothy Stello and published by . This book was released on 2000 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Biochemical Properties of Class I Lysyl tRNA Synthetase written by Jeffrey David Levengood and published by . This book was released on 2007 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The family of aminoacyl-tRNA synthetases (aaRSs) performs the essential cellular function of charging tRNA molecules with their cognate amino acids. This enzyme family can be divided into two unrelated classes with each evolving from different origins. Lysyl-tRNA synthetase (LysRS) is the only synthetase known to have a form in each class. Steady-state kinetics were used to study the mechanisms which LysRS1 employs to recognize its substrates. The binding of lysine was analyzed by studying the ability of several lysine analogues to inhibit the aminoacylation reaction. It was found that the R-group plays a critical role in discrimination rather than the functional groups at the [alpha]-carbon. Within the R-group, the size of the chain was a very important point for discrimination. The binding of tRNALys was examined using both LysRS, mutated based on the modeled tRNALys bound to LysRS1, and tRNALys with mutant anticodons. Analysis of the bound tRNALys revealed that LysRS is able to specifically recognize the bases at anticodon positions 35 and 36, but not 34. The experiments with variant enzymes in relation to the model revealed LysRS1 likely uses a variety of bonds to recognize the anticodon. Aromatic residues form non-specific stacking interactions with the bases, charged and polar residues form specific hydrogen bonds with the bases, and other charged residues form non-specific electrostatic interactions with the phosphate backbone of the anticodon stem. Comparison of the mechanisms for substrate recognition between LysRS1 and LysRS2 revealed differences in the recognition of substrates that could be the cause for the divergence of the two enzymes. The two LysRSs were shown to have different patterns of inhibition to naturally occurring lysine analogues that had consequences for growth in vivo. With the tRNALys anticodon binding, it was found anticodon binding is much more important for binding with LysRS2 than LysRS1. This could have had consequences with the divergence of other synthetases that must recognize similar anticodons. The presence of LysRS1 may have allowed these other synthetases to put more emphasis on the anticodon in recognition of their cognate tRNA.

Download or read book Compositions of Orthogonal Lysyl tRNA and Aminoacyl tRNA Synthetase Pairs and Uses Thereof written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Compositions and methods of producing components of protein biosynthetic machinery that include orthogonal lysyl-tRNAs, orthogonal lysyl-aminoacyl-tRNA synthetases, and orthogonal pairs of lysyl-tRNAs/synthetases, which incorporate homoglutamines into proteins are provided in response to a four base codon. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins with homoglutamines using these orthogonal pairs.

Download or read book Study of Lysyl tRNA Systhetase and Lysine TRNAs from Bacillus Subtilus W23 written by Ronald Yan-li Chuang and published by . This book was released on 1971 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Variants of Human Lysyl trna Synthetase written by Chase A. McVey and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Aminoacyl-tRNA synthetases are an ancient family of enzymes that maintain the fidelity and efficiency of translating the cell’s genetic code. Specifically, they are responsible for the correct attachment of amino acids to their cognate tRNA molecules for use in ribosomal peptide synthesis. Erroneous placement of amino acids onto tRNAs, known as mischarging, can lead to incorrectly incorporated amino acids, misfolding, or degradation of protein products. This study examines several single nucleotide mutations in the human KARS gene which codes for lysyl-tRNA synthetase (LysRS). These mutations have been detected in patients and associated with severe neurodegenerative and sensory disabilities. By purification and in vitro steady-state aminoacylation experiments, it was revealed that the mutant LysRS proteins exhibit varying levels of reduced enzymatic activity. The decrease in activity may be due to disrupting LysRS dimerization in solution, altering contacts between the synthetase and the tRNA, or directly affecting active site residues. This could potentially lead to a build-up of uncharged tRNA in the cell. In response, protein synthesis could be restricted by a host of translational control pathways. The severe associated phenotypes may also be due to the modulation of LysRS’s alternative non-translational functions. Many synthetases have evolved appended domains and secondary functions that lie outside their canonical function in protein synthesis. LysRS is one such synthetase, having an N-terminally appended domain, the eukaryotic extension, in addition to its anticodon-binding and aminoacylation domains. The “bifunctional” KARS gene’s mRNA undergoes alternative splicing to produce both mitochondrial and cytoplasmic LysRS, as well as additional splice variant proteins. These splice variants often do not contain the canonical aminoacylation domain required for its role in protein synthesis but retain the appended domains. This study also examines the properties of one such protein: spliced protein N9, spLysRSN9, or simply N9. The N9 protein was expressed and purified from E. coli, characterized for oligomeric state and fold, and tested for binding of tRNA and aminoacylation. It was shown that N9 is a fully folded dimeric protein in solution that could bind tRNAs in a similar manner to LysRS, but is catalytically inactive. While previously detected in Jurkat T-cell lysate, the reason behind the cellular production of these splice variants of LysRS remains unclear.

Download or read book Liu San qie written by and published by . This book was released on 1962 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Rationale for the Evolutionary Retention of Two Unrelated Lysyl tRNA Synthetases written by Sandro Fernandes Ataide and published by . This book was released on 2006 with total page 183 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Lysine insertion during coded protein synthesis requires lysyl-tRNALys, which is synthesized by lysyl-tRNA synthetase (LysRS). Two unrelated forms of LysRS are known: LysRS2, which is found in eukaryotes, most bacteria and a few archaea, and LysRS1, which is found in most archaea and a few bacteria. A detailed comparison of the amino acid recognition strategies of LysRS1 (Borrelia burgdorferi) and LysRS2 (Escherichia coli) was undertaken by studying the effects of lysine analogues on the aminoacylation reaction in vitro and in vivo. Also, based on comparisons of crystal structures and discrimination of lysine analogues by both LysRSs, the roles of the key residues in the active site of LysRS2 (lysS encoded) from E. coli were determined in vitro and in vivo. The differences in resistance to naturally occurring non-cognate amino acids suggest the distribution of LysRS1 and LysRS2 contributes to quality control during protein synthesis. LysRS1 and LysRS2 are not normally found together within one organism. In the pathogen Bacillus cereus both forms of LysRS are encoded; to investigate what role these two LysRSs might play in B. cereus, their RNA substrate specificities were investigated. It was found that in B. cereus the two different LysRSs together aminoacylate a small RNA of unknown function named tRNAOther. Aminoacylation of tRNAOther was found to be confined to stationary phase, suggesting a role for this non-canonical tRNA in growth phase-specific protein synthesis. Analysis of the non-canonical Watson-Crick base pairs and a bulge in the predicted secondary structure of tRNAOther indicate the importance of these identity elements in recognition by the LysRS1:LysRS2 complex. The role of tRNAOther in B. cereus was also investigated by the construction of a deletion strain, indicating that tRNAOther is not an essential gene. The results implicate tRNAOther in multiple regulatory functions that remain, as yet, uncharacterized.

Download or read book Purification and Partial Characterization of the Inducible Form of the Lysyl tRNA Synthetase Enzyme written by Robert Brazell and published by . This book was released on 1990 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Study of Lysyl tRNA Synthetase and Lysine TRNAs from Bacillus Subtilis W23 written by Ronald Yan-Li Chuang and published by . This book was released on 1971 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modulatory Roles of the Amino terminal Extension in Human Lysyl TRNA synthetase in Recognition and Catalysis written by Kwabena Poku Agyeman Boakye-Yiadom and published by . This book was released on 2002 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Aminoacyl tRNA Synthetases in Biology and Medicine written by Sunghoon Kim and published by Springer. This book was released on 2014-04-28 with total page 355 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book will focus on new molecular interactions and novel activities and the associated diseases that have been recently discovered from the studies of eukaryotic and mammalian aminoacyl-tRNA synthetases. In addition, the potential applications of ARS researches in biotechnology and medicine will be addressed.

Download or read book The Role of Lysyl tRNA Synthetase in Selective Packaging of TRNAlys3 Into HIV 1 written by Mohammad Hassan Javanbakht Rezai and published by . This book was released on 2003 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: "LysRS is carried into the viruses by its interaction with Gag. We have mapped the sites of interaction between HIV-1 Gag and LysRS using in vivo and in vitro techniques. We find that Gag sequences within the C-terminal domain of CA which contains the CA dimerization site, interact with LysRS sequences which include motif 1, which contains the LysRS dimerization site." --

Download or read book The Subcellular Distribution of the Lysine TRNA Isoacceptors in Normal and Virus transformed Cells and Studies of Lysyl tRNA Synthetase in Normal and Virus transformed Cells written by Kent Richard Thomas and published by . This book was released on 1980 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Protein Engineering of Lysyl TRNA Synthetase LysU from Escherichia Coli written by Alison Damaris Hindley and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mapping and Characterization of the Constitutive Lysyl tRNA Synthetase Gene of Escherichia Coli K 12 written by Rosemarie V. Emmerich and published by . This book was released on 1987 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Functional Significance of the Association of Lysyl tRNA Synthetase in the Multi enzyme Complex written by Samir Zaidan Wahab and published by . This book was released on 1984 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Non Natural Amino Acids written by and published by Academic Press. This book was released on 2009-07-24 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: By combining the tools of organic chemistry with those of physical biochemistry and cell biology, Non-Natural Amino Acids aims to provide fundamental insights into how proteins work within the context of complex biological systems of biomedical interest. The critically acclaimed laboratory standard for 40 years, Methods in Enzymology is one of the most highly respected publications in the field of biochemistry. Since 1955, each volume has been eagerly awaited, frequently consulted, and praised by researchers and reviewers alike. With more than 400 volumes published, each Methods in Enzymology volume presents material that is relevant in today's labs -- truly an essential publication for researchers in all fields of life sciences. - Demonstrates how the tools and principles of chemistry combined with the molecules and processes of living cells can be combined to create molecules with new properties and functions found neither in nature nor in the test tube - Presents new insights into the molecular mechanisms of complex biological and chemical systems that can be gained by studying the structure and function of non-natural molecules - Provides a "one-stop shop" for tried and tested essential techniques, eliminating the need to wade through untested or unreliable methods