Base-resolution detection of N4-methylcytosine in genomic DNA using 4mC-Tet-assisted-bisulfite- sequencing.

Restriction-modification (R-M) systems pose a major barrier to DNA transformation and genetic engineering of bacterial species. Systematic identification of DNA methylation in R-M systems, including N(6)-methyladenine (6mA), 5-methylcytosine (5mC) and N(4)-methylcytosine (4mC), will enable strategies to make these species genetically tractable. Although single-molecule, real time (SMRT) sequencing technology is capable of detecting 4mC directly for any bacterial species regardless of whether an assembled genome exists or not, it is not as scalable to profiling hundreds to thousands of samples compared with the commonly used next-generation sequencing technologies.

Identification and characterization of CbeI, a novel thermostable restriction enzyme from Caldicellulosiruptor bescii DSM 6725 and a member of a new subfamily of HaeIII-like enzymes.

Potent HaeIII-like DNA restriction activity was detected in cell-free extracts of Caldicellulosiruptor bescii DSM 6725 using plasmid DNA isolated from Escherichia coli as substrate. Incubation of the plasmid DNA in vitro with HaeIII methyltransferase protected it from cleavage by HaeIII nuclease as well as cell-free extracts of C. bescii.

Single amino acid changes in the predicted RNase H domain of Escherichia coli RNase G lead to complementation of RNase E deletion mutants.

The endoribonuclease RNase E of Escherichia coli is an essential enzyme that plays a major role in all aspects of RNA metabolism. In contrast, its paralog, RNase G, seems to have more limited functions. It is involved in the maturation of the 5' terminus of 16S rRNA, the processing of a few tRNAs, and the initiation of decay of a limited number of mRNAs but is not required for cell viability and cannot substitute for RNase E under normal physiological conditions.