EC Number   |
General Information |
Reference |
|---|
   2.1.1.297 | more |
analysis of folding of a small five-helix protein domain at the N-terminal domain of Escherichia coli N5-glutamine methyltransferase HemK in real time. The isolated HemK N-terminal domain (residues 1 to 73) forms a stable alpha-helical structure independent of the C-terminal domain. Cotranslational folding of the protein, which folds autonomously and rapidly in solution, proceeds through a compact, non-native conformation that forms within the peptide tunnel of the ribosome. The compact state rearranges into a native-like structure immediately after the full domain sequence has emerged from the ribosome. Both folding transitions are rate-limited by translation, allowing for quasi-equilibrium sampling of the conformational space restricted by the ribosome. Cotranslational folding may be typical of small, intrinsically rapidly folding protein domains |
737266 |
| 2.1.1.297 | more |
the cotranslational folding of two small protein domains of different folds - the alpha-helical N-terminal domain of HemK and the beta-rich FLN5 filamin domain - by measuring the force that the folding protein exerts on the nascent chain when located in different parts of the ribosome exit tunnel (force-profile analysis, or FPA), allowing us to compare FPA to three other techniques currently used to study cotranslational folding: real-time FRET, photoinduced electron transfer, and NMR, method evaluation, overview |
757438 |
| 2.1.1.297 | more |
the N-terminal alpha-helical domain of the universally conserved N5-glutamine methyltransferase HemK is compacted within the exit tunnel and rearranges into the native fold upon emerging from the ribosome. Analysis of the rapid kinetics of translation and folding monitored by fluorescence resonance energy transfer and photoinduced electron transfer using global fitting to a model for synthesis of the 112-amino acid HemK fragment. The co-translational folding trajectory of HemK starts within the tunnel and passes through four kinetically distinct folding intermediates that may represent sequential docking of helices to a growing compact core. The kinetics of the process is defined entirely by translation |
756050 |
| 2.1.1.297 | physiological function |
a hemK knockout suffers severe growth defects and shows a global shift in gene expression to anaerobic respiration. This shift may lead to the abrogation of photosensitivity by reducing the oxidative stress. Suppressor mutations that abrogate the growth defects of the hemK knockout strain are caused by a threonine to alanine change at codon 246 of polypeptide chain release factor RF2, indicating that hemK plays a role in translational termination. The hemK knockout strain shows an enhanced rate of read-through of nonsense codons and induction of transfer-mRNA-mediated tagging of proteins within the cell. HemK methylates RF1 and RF2 in vitro within the tryptic fragment containing the conserved GGQ motif, and hemK is required for the methylation within the same fragment of, at least, RF1 in vivo |
728709 |
| 2.1.1.297 | physiological function |
chlamydial isoform PrmC expression suppresses the growth defect of a prmC knockout strain of Escherichia coli K-12. Overexpression of PrmC in Escherichia coli strongly retards growth to the level of neative control |
-, 727743 |
| 2.1.1.297 | physiological function |
deletion of peptide release factor N5-glutamine methylase leads to very poor growth on rich media and abolishes methylation of release factor RF1. Fast growing spontaneous revertants of the deletion strain contain the mutation T246A or T246S in release factor RF2 |
724843 |
| 2.1.1.297 | physiological function |
the cell proliferation decreases after RNAi with Hemk1 |
728277 |
| 2.1.1.297 | physiological function |
the enzyme modifies the glutamine residue in the universally conserved glycylglycylglutamine (GGQ) motif of peptide chain release factor, resulting in almost complete loss of release activity |
-, 725975 |
