Editing Corynebacterium diphtheriae (section)

==Genetics==
The genome of ''C. diphtheriae'' consists of a single circular chromosome of 2.5 Mbp, with no [[plasmid]]s.<ref name="pmid14602910">{{cite journal | vauthors = Cerdeño-Tárraga AM, Efstratiou A, Dover LG, Holden MT, Pallen M, Bentley SD, Besra GS, Churcher C, James KD, De Zoysa A, Chillingworth T, Cronin A, Dowd L, Feltwell T, Hamlin N, Holroyd S, Jagels K, Moule S, Quail MA, Rabbinowitsch E, Rutherford KM, Thomson NR, Unwin L, Whitehead S, Barrell BG, Parkhill J | display-authors = 6 | title = The complete genome sequence and analysis of Corynebacterium diphtheriae NCTC13129 | journal = Nucleic Acids Research | volume = 31 | issue = 22 | pages = 6516–6523 | date = November 2003 | pmid = 14602910 | pmc = 275568 | doi = 10.1093/nar/gkg874 }}</ref> Its genome shows an extreme [[GC skew|compositional bias]], being noticeably higher in G+C near the origin than at the terminus.<ref name=":2"/>

The ''Corynebacterium diphtheriae'' genome is a single circular chromosome that has no plasmids. These chromosomes have a high G+C content which is what contributes to their high genetic diversity. The high content of guanine and cytosine is not constant across the entire genome of the bacteria. There is a terminus of replication around the ~740kb region that causes a decrease in the G+C content. In other bacteria, it is often seen that the G+C content gets smaller near the terminus, but ''C. diphtheriae'' is a considerably strong genome that has this occurrence. Chromosomal replication is one of the ways this happens within this genome.<ref name=":2">{{Cite journal |last1=Cerdeño-Tárraga |first1=A. M. |last2=Efstratiou |first2=A. |last3=Dover |first3=L. G. |last4=Holden |first4=M. T. G. |last5=Pallen |first5=M. |last6=Bentley |first6=S. D. |last7=Besra |first7=G. S. |last8=Churcher |first8=C. |last9=James |first9=K. D. |last10=De Zoysa |first10=A. |last11=Chillingworth |first11=T. |last12=Cronin |first12=A. |last13=Dowd |first13=L. |last14=Feltwell |first14=T. |last15=Hamlin |first15=N. |date=2003-11-15 |title=The complete genome sequence and analysis of Corynebacterium diphtheriae NCTC13129 |journal=Nucleic Acids Research |volume=31 |issue=22 |pages=6516–6523 |doi=10.1093/nar/gkg874 |issn=0305-1048 |pmid=14602910|pmc=275568 }}</ref>