Chlorella virus SC-1A encodes at least six DNA methyltransferases (MTases): four N6-methyldeoxyadenine (m6A) MTases, M·CviSI (TGCmA), M·CviSII (CmATG), M·CviSIII (TCGmA) and M·CviSIV (GmATC), one 5-methyldeoxycytosine (m5C) MTase, M·CviSV (~ RCmCG), and one nonfunctional m5C MTase, M·CviSVI, which is homologous to the MTase M·CviJI [RGmC(T/C/G)] produced by another chlorella virus IL-3A. Genes encoding three of the SC-1A m6A MTases (M·CviSI, M·CviSII, and M·CviSIII) and the nonfunctional m5C MTase were cloned and sequenced. Neither M·CviSI nor M·CviSIII genes hybridized to genes for their respective isomethylomers, M·CviRI and M·CviBIII, from other chlorella viruses. However, the M·CviSII gene hybridized strongly to its M·CviAII isomethylomer gene from virus PBCV-1. Like the prototype chlorella virus PBCV-1, the SC-1A genome contains inverted terminal repeats, one of which is adjacent to the nonfunctional m5C MTase. The three cloned m6A MTase genes are distributed throughout the approx. 345 kb SC-1A genome.
- 5-Methyldeoxycytosine methyltransferase
- 5-Methyldeoxycytosine methyltransferase pseudogene
- N-methyldeoxyadenine methyltransferase
- Recombinant DNA
ASJC Scopus subject areas