RT Journal Article SR Electronic T1 Characterization of ori and parS-like functions in secondary genome replicons in Deinococcus radiodurans JF Life Science Alliance JO Life Sci. Alliance FD Life Science Alliance LLC SP e202000856 DO 10.26508/lsa.202000856 VO 4 IS 1 A1 Ganesh K Maurya A1 Hari S Misra YR 2021 UL https://www.life-science-alliance.org/content/4/1/e202000856.abstract AB The mechanisms underlying multipartite genome maintenance and its functional significance in extraordinary radioresistance of Deinococcus radiodurans are not well understood. The sequences upstream to parAB operons in chrII (cisII) and MP (cisMP) could stabilize an otherwise, non-replicative colE1 plasmid, in D. radiodurans. DnaA and cognate ParB proteins bound specifically with cisII and cisMP elements. The ΔcisII and ΔcisMP cells showed the reduced copy number of cognate replicons and radioresistance as compared with wild type. Fluorescent reporter–operator system inserted in chrI, chrII, and MP in wild type and cisII mutants showed the presence of all three replicons in wild-type cells. Although chrI was present in all the ΔcisII and ΔcisMP cells, nearly half of these cells had chrII and MP, respectively, and the other half had the reduced number of foci representing these replications. These results suggested that cisII and cisMP elements contain both origin of replication and parS-like functions and the secondary genome replicons (chrII and MP) are maintained independent of chrI and have roles in radioresistance of D. radiodurans.