Open AccessMycobacterium smegmatis dnaA region and autonomous replication activity
Author(s) -
Malini Rajagopalan,
Ming Hui Qin,
Donald R. Nash,
Murty V. V. S. Madiraju
Publication year - 1995
Publication title -
journal of bacteriology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.652
H-Index - 246
eISSN - 1067-8832
pISSN - 0021-9193
DOI - 10.1128/jb.177.22.6527-6535.1995
Subject(s) - dnaa , biology , mycobacterium smegmatis , replication factor c , dna replication , dnab helicase , seqa protein domain , origin of replication , pre replication complex , genetics , origin recognition complex , prokaryotic dna replication , ter protein , gene , control of chromosome duplication , eukaryotic dna replication , helicase , rna , mycobacterium tuberculosis , tuberculosis , medicine , pathology
Two key elements that are thought to be required for replication initiation in eubacteria are the DnaA protein, a trans-acting factor, and the replication origin, a cis-acting element. As a first step in studying the replication initiation process in mycobacteria, we have isolated a 4-kb chromosomal DNA fragment from Mycobacterium smegmatis that contains the dnaA gene. Nucleotide sequence analysis of this region revealed homologies with the rpmH gene, which codes for the ribosomal protein L34, the dnaA gene, which codes for the replication initiator protein DnaA, and the 5' end of the dnaN gene, which codes for the beta subunit of DNA polymerase III. Further, we provide evidence that when cloned into pUC18, a plasmid that is nonreplicative in M. smegmatis, the DNA fragment containing the dnaA gene and its flanking regions rendered the former capable of autonomous replication in M. smegmatis. We suggest that the M. smegmatis chromosomal origin of replication is located within the 4-kb DNA fragment.