Each month, a manuscript published in our flagship journal Microbiology is chosen by a member of the Editorial Board. This month, the paper is Promiscuity of methionine salvage pathway enzymes in Methanocaldococcus jannaschii, which was selected by Professor Christiane Dahl.
Christiane Dahl: S-adenosyl methionine (SAM) is an ubiquituous and essential cofactor involved in methyl group transfers, transsulfururylation and aminopropylation. In the course of polyamine biosynthesis, SAM is transformed into 5′-methylthioadenosine from which sulfur is recycled via the methionine salvage pathway. While this pathway is well described for aerobes and facultatively anaerobic microorganisms, considerable knowledge gaps exist for obligately anaerobic prokaryotes. Miller et al. started to close these gaps by unravelling important steps of methionine salvage in methanogenic archaea. The work is well presented and provides a sound basis for future studies on methionine salvage in anaerobes.
Promiscuity of methionine salvage pathway enzymes in Methanocaldococcus jannaschii
A weakness of the life sciences is our inability to predict enzymatic function of genes. Our work aims to establish gene function by discovering new biosynthetic pathways and enzyme functions within the pathway. Using the well-studied oxygen dependent methionine salvage pathway as a guide, we searched for new pathways in methanogens. Here, we established the first three predicted methanogenic enzymes have the same function as in the aerobic pathway but with promiscuous activities, implying additional roles. However, how methanogens are able to circumvent the use of oxygen has yet to be discovered, but will likely lead to new biochemistry.
To access the full paper, click here. Editor’s Choice articles published in Microbiology are free to read.