Related Experiment Video
Updated: Jun 23, 2026

Producing Gene Deletions in Escherichia coli by P1 Transduction with Excisable Antibiotic Resistance Cassettes
Published on: September 1, 2018
Homocysteine editing and growth inhibition in Escherichia coli
Marta Sikora1,2, Hieronim Jakubowski1,2
1Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznań, Poland.
Abstract:
In Escherichia coli homocysteine (Hcy) is metabolically converted to the thioester Hcy-thiolactone in ATP-consuming reactions catalysed by methionyl-, isoleucyl- and leucyl-tRNA synthetases. Here we show that growth inhibition caused by supplementation of E. coli cultures with Hcy is accompanied by greatly increased accumulation of Hcy-thiolactone. Energy dissipation for Hcy editing increases 100-fold in the presence of exogenous Hcy and reaches one mole of ATP unproductively dissipated for Hcy-thiolactone synthesis per each mole of ATP that is consumed for methionine activation. Inhibiting Hcy-thiolactone synthesis with isoleucine, leucine or methionine accelerates bacterial growth in Hcy-supplemented cultures. Growth rates in Hcy-inhibited cultures are inversely related to the accumulation of Hcy-thiolactone. We also show that the levels of protein N-linked Hcy modestly increase in E. coli cells in Hcy-supplemented cultures. The results suggest that Hcy editing restrains bacterial growth.
More Related Videos
Related Concept Videos
Stringent Response in E. coli
Mismatch Repair
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...
RNA Editing
Bacterial Protein Maturation
Inhibitors of Bacterial Protein Synthesis
Chemotaxis in E. coli

