Sequence and organization of pXO1, the large Bacillus anthracis plasmid harboring the anthrax toxin genes.

TitleSequence and organization of pXO1, the large Bacillus anthracis plasmid harboring the anthrax toxin genes.
Publication TypeJournal Article
Year of Publication1999
AuthorsOkinaka, RT, Cloud, K, Hampton, O, Hoffmaster, AR, Hill, KK, Keim, P, Koehler, TM, Lamke, G, Kumano, S, Mahillon, J, Manter, D, Martinez, Y, Ricke, D, Svensson, R, Jackson, PJ
JournalJ Bacteriol
Volume181
Issue20
Pagination6509-15
Date Published1999 Oct
ISSN0021-9193
KeywordsAntigens, Bacterial, Bacillus anthracis, Bacterial Toxins, DNA, Bacterial, Genes, Bacterial, Molecular Sequence Data, Open Reading Frames, Plasmids, Recombination, Genetic, Replication Origin, Restriction Mapping, Sequence Analysis, DNA, Sequence Homology
Abstract

The Bacillus anthracis Sterne plasmid pXO1 was sequenced by random, "shotgun" cloning. A circular sequence of 181,654 bp was generated. One hundred forty-three open reading frames (ORFs) were predicted using GeneMark and GeneMark.hmm, comprising only 61% (110,817 bp) of the pXO1 DNA sequence. The overall guanine-plus-cytosine content of the plasmid is 32.5%. The most recognizable feature of the plasmid is a "pathogenicity island," defined by a 44.8-kb region that is bordered by inverted IS1627 elements at each end. This region contains the three toxin genes (cya, lef, and pagA), regulatory elements controlling the toxin genes, three germination response genes, and 19 additional ORFs. Nearly 70% of the ORFs on pXO1 do not have significant similarity to sequences available in open databases. Absent from the pXO1 sequence are homologs to genes that are typically required to drive theta replication and to maintain stability of large plasmids in Bacillus spp. Among the ORFs with a high degree of similarity to known sequences are a collection of putative transposases, resolvases, and integrases, suggesting an evolution involving lateral movement of DNA among species. Among the remaining ORFs, there are three sequences that may encode enzymes responsible for the synthesis of a polysaccharide capsule usually associated with serotype-specific virulent streptococci.

DOI10.1128/JB.181.20.6509-6515.1999
Alternate JournalJ Bacteriol
PubMed ID10515943
PubMed Central IDPMC103788
Grant ListR01 AI033537 / AI / NIAID NIH HHS / United States
AI33537 / AI / NIAID NIH HHS / United States

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