Characterization and Sequence Analysis of Helicobacter pylori Cryptic Plasmid (pHP489).
- Author:
Myung Je CHO
1
;
Jae Young SONG
;
Yeo Jeong CHOI
;
Woo Kon LEE
;
Seung Chul BAIK
;
Bok Deok RYU
;
Sang Haeng CHOI
;
Young Seok JEON
;
In Girl LEE
;
Kwang Ho RHEE
Author Information
1. Department of Microbiology, Gyeongsang National University College of Medicine, 92 Chilam-dong, Chinju, Kyung-Nam, Republic of Korea. mjecho@gshp.gsnu.ac.kr
- Publication Type:Original Article
- Keywords:
H. pylori;
Cryptic plasmid;
Nucleotide sequence;
Sequence analysis
- MeSH:
Animals;
Anti-Bacterial Agents;
Base Composition;
Base Sequence;
Binding Sites;
Codon, Initiator;
Consensus Sequence;
Cytosol;
DNA;
Ecthyma, Contagious;
Helicobacter pylori*;
Helicobacter*;
Mycoplasma mycoides;
Plasmids*;
Repetitive Sequences, Nucleic Acid;
Sequence Analysis*;
Terminator Regions, Genetic
- From:Journal of the Korean Society for Microbiology
1998;33(4):343-352
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
The DNA sequence of a plasmid named pHP489 of Helicobacter pylori strain 489 was determined and analyzed to characterize its replication apparatus. The pHP489 plasmid consisted of 1,222 bp and had an overall G+C content of 33.1%. An ORF was predicted to encode the putative protein of 239 amino acid residues (28 kDa). A putative ribosomal binding site and a potential terminator sequence are located upstream and downstream of the ORF, respectively. However, the consensus sequence for a promoter in upstream of ORF was not found. A potential dna A box was found at 317 nt upstream of a start codon and followed by two-57 bp directed repeats and an inverted repeat. The DNA homology was found in the regions of less than 90 bp among pHPK255, pHPM180, and pHel1 of other H. pylori plasmids and Mycoplasma mycoides plasmids. pHP489K that was produced by pHP489 sequence and C. jejuni derived aph(3')-III, was transformed to various H. pylori isolates and were stably maintained in the H. pylori host without the addition of selective antibiotics for the 30-times subcultues. The plasmic vector, in which the ORF region of pHP489 DNA was deleted, could be transformed into H. pylori. However, the plasmid vector, whose the direct repeats region of pHP489 DNA was deleted, failed to be transformed. The direct repeats region of pHP489 DNA was confirmed to be bound with cytosolic factors of H. pylori. These results showed that the direct repeats region of pHP489 DNA is an essential apparatus by which the plasmid could be replicacted in H. pylori. And pHP489 plasmid was supposed to be replicated by host factors rather than plasmic-encoded factors.
