Altered methionyl-tRNA synthetase in a Spirulina platensis mutant resistant to ethionine.

Functionally impaired tRNA from ethionine treated rats as detected in injected Xenopus oocytes.

Treatment of rats with ethionine was found to cause severe impairment in the aminoacylation capacity of tRNA. This effect was only observed when assayed in injected oocytes, while invitro assays of aminoacylation failed to detect differences between normal tRNA and tRNA from ethionine treated animals. The effect of ethionine on the tRNA population was not uniform and differed for various amino ...

Investigating the Effect of Spirulina Platensis Microalgae on Textural and Sensory Properties of Baguette Bread

Background: Spirulina platensis is a photosynthetic microalgae with fibrous filamentous that belongs to the cyanobacteria family. In this study, we investigated the effects of ethanol and methanol extracts as well as the powder of spirulina platensis microelements on the sensory and texture properties of the bread. Methods: In order to determine the texture characteristics, we applied a texture...

In vivo synthesis of adenylylated bis(5'-nucleosidyl) tetraphosphates (Ap4N) by Escherichia coli aminoacyl-tRNA synthetases.

The role of aminoacyl-tRNA synthetases in the in vivo synthesis of adenylylated bis(5'-nucleosidyl) tetraphosphates (Ap4N) was studied by measuring the concentration of these nucleotides in Escherichia coli cells overproducing lysyl-, methionyl- phenylalanyl-, or valyl-tRNA synthetase. Overproduction of each aminoacyl-tRNA synthetase (20- to 80-fold) was accompanied by a significant increase in...

Supporting Information Appendix for: Mutant Methionyl-tRNA Synthetase from Bacteria Enables Site-Selective N-terminal Labeling of Proteins Expressed in Mammalian Cells

Cell-selective metabolic labeling of proteins.

Metabolic labeling of proteins with the methionine surrogate azidonorleucine can be targeted exclusively to specified cells through expression of a mutant methionyl-tRNA synthetase (MetRS). In complex cellular mixtures, proteins made in cells that express the mutant synthetase can be tagged with affinity reagents (for detection or enrichment) or fluorescent dyes (for imaging). Proteins made in ...