Low-molecular-weight thiols(LMWTs)are widely distributing in waters and soils,which can act as electron shuttling compounds during biotic or abiotic processes.
In addition to DNA cytosine methylation(5-methyl-2-deoxycytidine,m5dC),DNA adenine methylation(N6-methyl-2-deoxyadenosine,m6dA)is another DNA modification that has been discovered in eukaryotes.