Synthetic post-translational modifications of elongation factor P using the ligase EpmA

Canonically, tRNA synthetases charge tRNA. However, the lysyl-tRNA synthetase paralog EpmA catalyzes the attachment of (R)-beta-lysine to the epsilon-amino group of lysine 34 of the translation elongation factor P (EF-P) inEscherichia coli. This modification is essential for EF-P-mediated translational rescue of ribosomes stalled at consecutive prolines. In this study, we determined the kinetics of EpmA and its variant EpmA_A298G to catalyze the post-translational modification of K34 in EF-P with eight noncanonical substrates. In addition, acetylated EF-P was generated using an amber suppression system. The impact of these synthetically modified EF-P variants onin vitrotranslation of a polyproline-containing NanoLuc luciferase reporter was analyzed. Our results show that natural (R)-beta-lysylation was more effective in rescuing stalled ribosomes than any other synthetic modification tested. Thus, our work not only provides new biochemical insights into the function of EF-P, but also opens a new route to post-translationally modify proteins using EpmA

К вопросу борьбы с обледенением стальных тросов

The understanding of biological processes, e.g. related to cardio-vascular disease and treatment, can significantly be improved by numerical simulation. In this paper, we present an approach for a multiscale simulation environment, applied for the prediction of in-stent re-stenos is. Our focus is on the coupling of distributed, heterogeneous hardware to take into account the different requirements of the coupled sub-systems concerning computing power. For such a concept, which is an extension of the standard multiscale computing approach, we want to apply the term Distributed Multiscale Computing

System overview for the multi-element corrector magnets and controls for the Fermilab Booster

To better control the beam position, tune, and chromaticity in the Fermilab Booster synchrotron, a new package of six corrector elements has been designed, incorporating both normal and skew orientations of dipole, quadrupole, and sextupole magnets. The devices are under construction and will be installed in 48 locations in the Booster accelerator. Each of these 288 corrector magnets will be individually powered. Each of the magnets will be individually controlled using operator programmed current ramps designed specifically for each type of Booster acceleration cycle. This paper provides an overview of the corrector magnet installation in the accelerator enclosure, power and sensor interconnections, specifications for the switch-mode power supplies, rack and equipment layouts, controls and interlock electronics, and the features of the operator interface for programming the current ramps and adjusting the timing of the system triggers

Mass Limit on a Positively Charged Heavy Muon

We report a preliminary search for a positively charged lepton (Y+) coupled directly to the μ- and νμ (i.e., muon number = + 1). Using the production process νμ+N→Y++anything, we have looked for the μ+ from the decay Y+→μ++νμ+νμ. The expected number of μ+ events is given as a function of the heavy-lepton mass, the branching fraction to muons, and the heavy-lepton coupling. For typical gauge-theory predictions, we obtain the 90% confidence limit MY>2 GeV/c^2

Experimental Comparison of Neutrino and Muon Velocities

The velocities of neutrinos and muons originating from π+ and K+ decays have been compared using the California Institute of Technology-Fermilab detector in a narrow-band neutrino beam. A time-of-flight comparison between positive muons and neutrinos, as indicated by the final-state negative muons in neutrino interactions, yields |βν-βμ|<~0.4×10-3 (99% confidence level). We assume that |1-βμ|<10-5 for these muons