Type III 5-methylcytosine modification of DNA in Neisseria gonorrhoeae.

We present here the first report of a type III methyltransferase that modifies a cytosine. Neisseria gonorrhoeae 82409/55 (pJD1) modifies the first cytosine on only one strand from the 5' end of the nonpalindromic sequence: (Formula; see text). We have called this modifying activity M X NgoVIII.