Characterization of plasmids from human infant Bifidobacterium strains: Sequence analysis and construction of E. coli–Bifidobacterium shuttle vectors
Abstract
A survey of infant fecal Bifidobacterium isolates for plasmid DNA revealed that a significant portion of the strains, 17.6%, carry small plasmids. The majority of plasmid-harboring strains belonged to the Bifidobacterium longum/infantis group. Most of the plasmids could be assigned into two groups based on their sizes and the restriction profiles. Three plasmids, pB44 (3.6 kb) from B. longum, pB80 (4.9 kb) from Bifidobacterium bifidum, and pB21a (5.2kb) from Bifidobacterium breve were sequenced. While the former two plasmids were found to be highly similar to previously characterized rolling-circle replicating pKJ36 and pKJ56, respectively, the third plasmid, pB21a, does not share significant nucleotide homology with known plasmids. However, it might be placed into the pCIBb1-like group of bifidobacterial rolling-plasmids based on the homology of its Rep protein and the overall molecular organization. Two sets of Escherichia coli-Bifidobacterium shuttle vectors constructed based on pB44 and pB80 replicons were capable of transforming B. bifidum and B. breve strains with efficiency up to 3x10(4)cfu/microg DNA. Additionally, an attempt was made to employ a broad host range conjugation element, RP4, in developing of E. coli-Bifidobacterium gene transfer system.
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In the absence of characteristic plasmids in B. bifidum, these clusters likely represent episome-derived elements integrated into the chromosome.
“In the absence of characteristic plasmids in B. bifidum , these clusters likely represent episome-derived elements integrated into the chromosome [78-81] .”
From Genome-scale insights into the metabolic landscape and evolutionary development of Bifidobacterium bifidum (2026) · cites this paper as [78]
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- Authors
- Shkoporov, A. N., Efimov, B. A., Khokhlova, E. V., Steele, J. L., Kafarskaia, L. I., & Smeianov, V. V.
- Affiliations
- Pirogov Russian National Research Medical University (RU)
- University of Wisconsin–Madison (US)
- Corresponding author
- Smeianov, Vladimir V.
- Venue
- Plasmid
- Publisher
- Elsevier BV
- Published
- 2008-09
- Volume
- 60
- Issue
- 2
- Pages
- 136-148
- ISSN
- 0147-619X (ISSN-L)
- OpenAlex
- W2069926876
- Cited by
- 30
- References
- 63
- Citations by year
- 2026: 1 · 2024: 1 · 2021: 4 · 2018: 1 · 2017: 2 · 2016: 1 · 2015: 4 · 2014: 2 · 2013: 1 · 2012: 6
- FWCI
- 1.33
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Plasmid (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Bacterial Genetics and Biotechnology
- Life Sciences › Agricultural and Biological Sciences › Food Science › Probiotics and Fermented Foods
- Physical Sciences › Environmental Science › Ecology › Bacteriophages and microbial interactions
- Keywords
- Bifidobacterium, infant gut microbiota, plasmids, rolling circle replication, Rep protein, Bifidobacterium longum, Bifidobacterium bifidum, Bifidobacterium breve, shuttle vector, conjugation, RP4, plasmid sequence analysis
- MeSH terms
- Base Sequence, Bifidobacterium, Cloning, Molecular, Escherichia coli, Feces, Female, Genes, Bacterial, Genetic Vectors, Humans, Infant, Male, Molecular Sequence Data, Plasmids, Open Reading Frames, Sequence Alignment, Sequence Analysis
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