Extrachromosomal DNA membrane bound nucleus like the eukaryotes, they do contain a nucleoid region in which the main chromosome is found. Extrachromosomal DNA exists in prokaryotes outside the nucleoid region as circular or linear plasmids. Bacterial plasmids are typically short sequences, consisting of 1 kilobase (kb) to a few hundred kb segments, and contain an origin of replication which allows the plasmid to replicate independently of the bacterial chromosome. The total number of a particular plasmid within a cell is referred to as the copy number and can range from as few as two copies per cell to as many as several
Single-cell DNA template strand sequencing Single-cell DNA template strand sequencing Single-cell DNA template strand sequencing, or strand-seq, is a technique for the selective sequencing of a daughter cell’s parental template strands. This technique has many applications, including the identification of sister chromatid exchanges in the parental cell prior to segregation, the identification of misoriented contigs during alignment of reads to the reference genome, and the assessment of non-random segregation of sister chromatids. Strand-seq (single strand sequencing) was first described in 2012 as a technique to isolate sequenced reads from parental template strands in single-cell DNA libraries. As a proof of concept study, the authors demonstrated