1
|
Zou J, Tang Z, Yan J, Liu H, Chen Y, Zhang D, Zhao J, Tang Y, Zhang J, Xia Y. Dissemination of Linezolid Resistance Through Sex Pheromone Plasmid Transfer in Enterococcus faecalis. Front Microbiol 2020; 11:1185. [PMID: 32582110 PMCID: PMC7288747 DOI: 10.3389/fmicb.2020.01185] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Accepted: 05/11/2020] [Indexed: 12/19/2022] Open
Abstract
Despite recent recognition of the ATP-binding cassette protein OptrA as an important mediator of linezolid resistance in Enterococcus faecalis worldwide, the mechanisms of optrA gene acquisition and transfer remain poorly understood. In this study, we performed comprehensive molecular and phenotypic profiling of 44 optrA-carrying E. faecalis clinical isolates with linezolid resistance. Pulse-field gel electrophoresis and DNA hybridization revealed the presence of optrA in the plasmid in 26 (59%) isolates and in the chromosome in 18 (41%) isolates. Conjugation experiments showed a successful transfer of optrA in 88.5% (23/26) of isolates carrying optrA in plasmids while no transfer occurred in any isolates carrying optrA in the chromosome (0/18). All 23 transconjugants exhibited in vitro resistance to linezolid and several other antibiotics and were confirmed to contain optrA and other resistance genes. Plasmid typing demonstrated a predominance (18/23,78%) of rep 9-type plasmids (pCF10 prototype) known to be the best studied sex pheromone responsive plasmids. Full plasmid genome sequencing of one isolate revealed the presence of drug resistance genes (optrA and fexA) and multiple sex pheromone response genes in the same plasmid, which represents the first sex pheromone responsive plasmid carrying optrA from a clinical isolate. PCR-based genotyping revealed the presence of three key sex pheromone response genes (prgA, prgB, and prgC) in 23 optrA-carrying isolates. Finally, functional studies of these isolates by clumping induction assay detected different degrees of clumping in 17 isolates. Our analysis suggests that optrA-mediated linezolid resistance can be widely disseminated through sex pheromone plasmid transfer.
Collapse
Affiliation(s)
- Jiaqi Zou
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zhaobing Tang
- Department of Urologic Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Jia Yan
- Department of Laboratory Medicine, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Hang Liu
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yingzhu Chen
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Dawei Zhang
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Jinxin Zhao
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yu Tang
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Jing Zhang
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yun Xia
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| |
Collapse
|
2
|
Ó Cuív P, Giri R, Hoedt EC, McGuckin MA, Begun J, Morrison M. Enterococcus faecalis AHG0090 is a Genetically Tractable Bacterium and Produces a Secreted Peptidic Bioactive that Suppresses Nuclear Factor Kappa B Activation in Human Gut Epithelial Cells. Front Immunol 2018; 9:790. [PMID: 29720977 PMCID: PMC5915459 DOI: 10.3389/fimmu.2018.00790] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 03/29/2018] [Indexed: 12/20/2022] Open
Abstract
Enterococcus faecalis is an early coloniser of the human infant gut and contributes to the development of intestinal immunity. To better understand the functional capacity of E. faecalis, we constructed a broad host range RP4 mobilizable vector, pEHR513112, that confers chloramphenicol resistance and used a metaparental mating approach to isolate E. faecalis AHG0090 from a fecal sample collected from a healthy human infant. We demonstrated that E. faecalis AHG0090 is genetically tractable and could be manipulated using traditional molecular microbiology approaches. E. faecalis AHG0090 was comparable to the gold-standard anti-inflammatory bacterium Faecalibacterium prausnitzii A2-165 in its ability to suppress cytokine-mediated nuclear factor kappa B (NF-κB) activation in human gut-derived LS174T goblet cell like and Caco-2 enterocyte-like cell lines. E. faecalis AHG0090 and F. prausnitzii A2-165 produced secreted low molecular weight NF-κB suppressive peptidic bioactives. Both bioactives were sensitive to heat and proteinase K treatments although the E. faecalis AHG0090 bioactive was more resilient to both forms of treatment. As expected, E. faecalis AHG0090 suppressed IL-1β-induced NF-κB-p65 subunit nuclear translocation and expression of the NF-κB regulated genes IL-6, IL-8 and CXCL-10. Finally, we determined that E. faecalis AHG0090 is distantly related to other commensal strains and likely encodes niche factors that support effective colonization of the infant gut.
Collapse
Affiliation(s)
- Páraic Ó Cuív
- The University of Queensland Diamantina Institute, Translational Research Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Rabina Giri
- Mater Research Institute - The University of Queensland, Translational Research Institute, Brisbane, QLD, Australia
| | - Emily C Hoedt
- The University of Queensland Diamantina Institute, Translational Research Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Michael A McGuckin
- Mater Research Institute - The University of Queensland, Translational Research Institute, Brisbane, QLD, Australia
| | - Jakob Begun
- Mater Research Institute - The University of Queensland, Translational Research Institute, Brisbane, QLD, Australia
| | - Mark Morrison
- The University of Queensland Diamantina Institute, Translational Research Institute, The University of Queensland, Brisbane, QLD, Australia
| |
Collapse
|
3
|
Maidin MST, Song AAL, Jalilsood T, Sieo CC, Yusoff K, Rahim RA. Construction of a novel inducible expression vector for Lactococcus lactis M4 and Lactobacillus plantarum Pa21. Plasmid 2014; 74:32-8. [PMID: 24879963 DOI: 10.1016/j.plasmid.2014.05.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2013] [Revised: 05/13/2014] [Accepted: 05/16/2014] [Indexed: 12/27/2022]
Abstract
A vector that drives the expression of the reporter gusA gene in both Lactobacillus plantarum and Lactococcus lactis was constructed in this study. This vector contained a newly characterized heat shock promoter (Phsp), amplified from an Enterococcus faecium plasmid, pAR6. Functionality and characterization of this promoter was initially performed by cloning Phsp into pNZ8008, a commercial lactococcal plasmid used for screening of putative promoters which utilizes gusA as a reporter. It was observed that Phsp was induced under heat, salinity and alkaline stresses or a combination of all three stresses. The newly characterized Phsp promoter was then used to construct a novel Lactobacillus vector, pAR1801 and its ability to express the gusA under stress-induced conditions was reproducible in both Lb. plantarum Pa21 and L. lactis M4 hosts.
Collapse
Affiliation(s)
- Mohd Shawal Thakib Maidin
- Department of Cell and Molecular Biology, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Adelene Ai-Lian Song
- Department of Cell and Molecular Biology, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Tannaz Jalilsood
- Department of Cell and Molecular Biology, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Chin Chin Sieo
- Department of Microbiology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Institute of Bioscience Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Khatijah Yusoff
- Department of Microbiology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Institute of Bioscience Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Raha Abdul Rahim
- Department of Cell and Molecular Biology, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Institute of Bioscience Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| |
Collapse
|
4
|
Eom HJ, Moon JS, Cho SK, Kim JH, Han NS. Construction of theta-type shuttle vector for Leuconostoc and other lactic acid bacteria using pCB42 isolated from kimchi. Plasmid 2012; 67:35-43. [DOI: 10.1016/j.plasmid.2011.11.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 10/19/2011] [Accepted: 11/02/2011] [Indexed: 11/17/2022]
|
5
|
Properties and construction of plasmid pFW213, a shuttle vector with the oral Streptococcus origin of replication. Appl Environ Microbiol 2011; 77:3967-74. [PMID: 21531841 DOI: 10.1128/aem.02828-10] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Streptococcus parasanguinis is among the most successful colonizers of the human body. Strain FW213 harbors a 7.0-kb cryptic plasmid, pFW213, with a copy number at 5 to 10 per chromosome. Sequence and functional analyses of pFW213 revealed that the open reading frame (ORF) encoding the replication protein (Rep) is essential for the replication of pFW213, and the putative plasmid addiction system (RelB and RelE) and an ORF (ORF6) with no known function are required for its stability. The minimal replicon of pFW213 contains the rep gene and its 5'-flanking 390-bp region. Within the minimal replicon, an A/T-rich region followed by 5 contiguous 22-bp repeats was located 5' of the ATG of rep. No single-stranded replication intermediates were detected in the derivatives of pFW213, suggesting that pFW213 replicates via the theta replication mechanism. The minimal replicon was unstable in streptococcal hosts without selection, but the stability was greatly enhanced in derivatives containing the intact relBE genes. A Streptococcus-Escherichia coli shuttle vector, pCG1, was constructed with the pFW213 replicon. Plasmid pCG1 features a multiple cloning region and a spectinomycin resistance determinant that is expressed in both Streptococcus spp. and E. coli. Various streptococcal DNA fragments were cloned in pCG1, and the recombinant constructs were stably maintained in the streptococcal hosts. Since pCG1 is compatible with the most widely used streptococcal replicon, pVA380-1, pCG1 will provide a much needed tool allowing the cloning of two genes that work in concert in the same host.
Collapse
|
6
|
Shareck J, Choi Y, Lee B, Miguez CB. Cloning Vectors Based on Cryptic Plasmids Isolated from Lactic Acid Bacteria:Their Characteristics and Potential Applications in Biotechnology. Crit Rev Biotechnol 2010; 24:155-208. [PMID: 15707158 DOI: 10.1080/07388550490904288] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Lactic acid bacteria (LAB) are Gram positive bacteria, widely distributed in nature, and industrially important as they are used in a variety of industrial food fermentations. The use of genetic engineering techniques is an effective means of enhancing the industrial applicability of LAB. However, when using genetic engineering technology, safety becomes an essential factor for the application of improved LAB to the food industry. Cloning and expression systems should be derived preferably from LAB cryptic plasmids that generally encode genes for which functions can be proposed, but no phenotypes can be observed. However, some plasmid-encoded functions have been discovered in cryptic plasmids originating from Lactobacillus, Streptococcus thermophilus, and Pediococcus spp. and can be used as selective marker systems in vector construction. This article presents information concerning LAB cryptic plasmids, and their structures, functions, and applications. A total of 134 cryptic plasmids collated are discussed.
Collapse
Affiliation(s)
- Julie Shareck
- Department of Food Science and Agricultural Chemistry, McGill University, Ste-Anne-de-Bellevue, Quebec, Canada
| | | | | | | |
Collapse
|
7
|
Construction of a new shuttle vector and its use for cloning and expression of two plasmid-encoded bacteriocins from Lactobacillus paracasei subsp. paracasei BGSJ2-8. Int J Food Microbiol 2010; 140:117-24. [PMID: 20439125 DOI: 10.1016/j.ijfoodmicro.2010.04.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Revised: 03/22/2010] [Accepted: 04/07/2010] [Indexed: 11/20/2022]
Abstract
A new shuttle-cloning vector, pA13, was constructed and successfully introduced into Escherichia coli, Lactobacillus and Lactococcus strains. It showed high segregational and structural stability in all three hosts. The natural plasmid pSJ2-8 from L. paracasei subsp. paracasei BGSJ2-8 was cloned into pA13 using BamHI to obtain the construct, pB5. Sequencing and in silico analysis of pB5 revealed fifteen open reading frames (ORF). Plasmid pSJ2-8 harbours genes encoding the production of two bacteriocins, BacSJ and acidocin 8912. Combined N-terminal amino acid sequencing of BacSJ in combination with DNA sequencing of the bacSJ2-8 gene enabled determination of the primary structure of bacteriocin BacSJ. The bacSJ2-8 gene encodes 68-amino-acid peptide with a double-glycine leader peptide consisting of 18 amino acids, followed by the orf2 (bacSJ2-8i) which encodes the immunity protein of BacSJ. The production and functional expression of BacSJ in homologous and heterologous hosts suggest that bacSJ2-8 and bacSJ2-8i together with the genes encoding the ABC transporter and accessory protein are the minimal requirements for production of BacSJ. Biochemical and genetic analyses showed that BacSJ belongs to class II bacteriocins.
Collapse
|
8
|
Kojic M, Lozo J, Jovcic B, Strahinic I, Fira D, Topisirovic L. A successful use of a new shuttle cloning vector pA13 for the cloning of the bacteriocins BacSJ and acidocin 8912. ARCH BIOL SCI 2010. [DOI: 10.2298/abs1002231k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
The aim of this paper was to research the molecular cloning of genes encoding the novel bacteriocin BacSJ from Lactobacillus paracasei subsp. paracasei BGSJ2-8 by using a newly constructed shuttle cloning vector pA13. A new shuttle-cloning vector, pA13, was constructed and successfully introduced into Escherichia coli, Lactobacillus and Lactococcus strains, showing a high segregational and structural stability in all three hosts. The natural plasmid pSJ2-8 from L. paracasei subsp. paracasei BGSJ2-8 was cloned in the pA13 using BamHI, obtaining the construct pB5. Sequencing and in silico analysis of the pB5 revealed 15 open reading frames (ORF). Plasmid pSJ2-8 harbors the genes encoding the production of two bacteriocins, BacSJ and acidocin 8912. The combined N-terminal amino acid sequencing of BacSJ in combination with DNA sequencing of the bacSJ2-8 gene enabled the determination of the primary structure of a bacteriocin BacSJ. The production and functional expression of BacSJ in homologous and heterologous hosts suggest that bacSJ2-8 and bacSJ2-8i together with the genes encoding the ABC transporter and accessory protein are the minimal requirement for the production of BacSJ. Biochemical and genetic analyses showed that BacSJ belongs to the class II bacteriocins. The shuttle cloning vector pA13 could be used as a tool for genetic manipulations in lactobacilli and lactococci. <br><br><b><font color="red">withdrawn; due to a printing error. Link to the Editorial Decision <u><a href="http://dx.doi.org/10.2298/ABS1004251U">10.2298/ABS1004251U</a></u></font></b><br>
Collapse
Affiliation(s)
- Milan Kojic
- Laboratory for the Molecular Genetics of Industrial Microorganisms, Institute of Molecular Genetics and Genetic Engineering, Belgrade
| | - Jelena Lozo
- Laboratory for the Molecular Genetics of Industrial Microorganisms, Institute of Molecular Genetics and Genetic Engineering, Belgrade
| | - B. Jovcic
- Laboratory for the Molecular Genetics of Industrial Microorganisms, Institute of Molecular Genetics and Genetic Engineering, Belgrade
| | - Ivana Strahinic
- Laboratory for the Molecular Genetics of Industrial Microorganisms, Institute of Molecular Genetics and Genetic Engineering, Belgrade
| | - D. Fira
- Laboratory for the Molecular Genetics of Industrial Microorganisms, Institute of Molecular Genetics and Genetic Engineering, Belgrade
| | - L. Topisirovic
- Laboratory for the Molecular Genetics of Industrial Microorganisms, Institute of Molecular Genetics and Genetic Engineering, Belgrade
| |
Collapse
|
9
|
Jensen LB, Garcia-Migura L, Valenzuela AJS, Løhr M, Hasman H, Aarestrup FM. A classification system for plasmids from enterococci and other Gram-positive bacteria. J Microbiol Methods 2009; 80:25-43. [PMID: 19879906 DOI: 10.1016/j.mimet.2009.10.012] [Citation(s) in RCA: 122] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Revised: 10/19/2009] [Accepted: 10/20/2009] [Indexed: 11/18/2022]
Abstract
A classification system for plasmids isolated from enterococci and other Gram-positive bacteria was developed based on 111 published plasmid sequences from enterococci and other Gram-positive bacteria; mostly staphylococci. Based on PCR amplification of conserved areas of the replication initiating genes (rep), alignment of these sequences and using a cutoff value of 80% identity on both protein and DNA level, 19 replicon families (rep-families) were defined together with several unique sequences. The prevalence of these rep-families was tested on 79 enterococcal isolates from a collection of isolates of animal and human origin. Difference in prevalence of the designed rep-families were detected with rep(9) being most prevalent in Enterococcus faecalis and rep(2) in Enterococcus faecium. In 33% of the tested E. faecium and 32% of the tested E. faecalis no positive amplicons were detected. Furthermore, conjugation experiments were performed obtaining 30 transconjugants when selecting for antimicrobial resistance. Among them 19 gave no positive amplicons indicating presence of rep-families not tested for in this experimental setup.
Collapse
Affiliation(s)
- L B Jensen
- National Food Institute, DTU, Division of Microbiology and Risk Assessment, Bülowsvej 27, DK-1790 Copenhagen V, Denmark.
| | | | | | | | | | | |
Collapse
|
10
|
Zhu Y, Zhang Y, Li Y. Understanding the industrial application potential of lactic acid bacteria through genomics. Appl Microbiol Biotechnol 2009; 83:597-610. [DOI: 10.1007/s00253-009-2034-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Revised: 05/04/2009] [Accepted: 05/04/2009] [Indexed: 10/20/2022]
|
11
|
Analysis of pYC2, a cryptic plasmid in Lactobacillus sakei BM5 isolated from kimchi. Biotechnol Lett 2008; 31:123-30. [DOI: 10.1007/s10529-008-9842-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2008] [Revised: 08/21/2008] [Accepted: 08/27/2008] [Indexed: 10/21/2022]
|
12
|
Engineering of a human vaginal Lactobacillus strain for surface expression of two-domain CD4 molecules. Appl Environ Microbiol 2008; 74:4626-35. [PMID: 18539799 DOI: 10.1128/aem.00104-08] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Women are at significant risk of heterosexually transmitted human immunodeficiency virus (HIV) infection, with the mucosal epithelium of the cervix and vagina serving as a major portal of entry. The cervicovaginal mucosa naturally harbors dynamic microflora composed predominantly of lactobacilli, which may be genetically modified to serve as a more efficient protective barrier against the heterosexual transmission of HIV. We selected a vaginal strain of Lactobacillus, L. jensenii 1153, for genetic modification to display surface-anchored anti-HIV proteins. Genomic sequencing analyses revealed that L. jensenii 1153 encodes several unique high-molecular-weight cell wall-anchored proteins with a C-terminal cell wall sorting LPQTG motif. In this report, we employed these proteins to express a surface-anchored two-domain CD4 (2D CD4) molecule in L. jensenii 1153. Our studies indicated that the C-terminal cell wall sorting signal LPQTG motif alone is insufficient to drive the surface expression of heterologous proteins, and the display of surface-anchored 2D CD4 molecules required native sequences of a defined length upstream of the unique C-terminal LPQTG cell wall sorting signal and the positively charged C terminus in a Lactobacillus-based expression system. The modified L. jensenii strain displayed 2D CD4 molecules that were uniformly distributed on bacterial surfaces. The surface-anchored 2D CD4 molecule was recognized by a conformation-dependent anti-CD4 antibody, suggesting that the expressed proteins adopted a native conformation. The establishment of this Lactobacillus-based surface expression system, with potential broad applicability, represents a major step toward developing an inexpensive yet durable approach to topical microbicides for the mitigation of heterosexual transmission of HIV and other mucosally transmitted viral pathogens.
Collapse
|
13
|
Characterization of endogenous plasmids from Lactobacillus salivarius UCC118. Appl Environ Microbiol 2008; 74:3216-28. [PMID: 18390685 DOI: 10.1128/aem.02631-07] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The genome of Lactobacillus salivarius UCC118 comprises a 1.83-Mb chromosome, a 242-kb megaplasmid (pMP118), and two smaller plasmids of 20 kb (pSF118-20) and 44 kb (pSF118-44). Annotation and bioinformatic analyses suggest that both of the smaller plasmids replicate by a theta replication mechanism. Furthermore, it appears that they are transmissible, although neither possesses a complete set of conjugation genes. Plasmid pSF118-20 encodes a toxin-antitoxin system composed of pemI and pemK homologs, and this plasmid could be cured when PemI was produced in trans. The minimal replicon of pSF118-20 was determined by deletion analysis. Shuttle vector derivatives of pSF118-20 were generated that included the replication region (pLS203) and the replication region plus mobilization genes (pLS208). The plasmid pLS203 was stably maintained without selection in Lactobacillus plantarum, Lactobacillus fermentum, and the pSF118-20-cured derivative strain of L. salivarius UCC118 (strain LS201). Cloning in pLS203 of genes encoding luciferase and green fluorescent protein, and expression from a constitutive L. salivarius promoter, demonstrated the utility of this vector for the expression of heterologous genes in Lactobacillus. This study thus expands the knowledge base and vector repertoire of probiotic lactobacilli.
Collapse
|
14
|
Horn N, Wegmann U, Narbad A, Gasson MJ. Characterisation of a novel plasmid p9785S from Lactobacillus johnsonii FI9785. Plasmid 2005; 54:176-83. [PMID: 16122563 DOI: 10.1016/j.plasmid.2005.01.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2004] [Revised: 01/26/2005] [Accepted: 01/27/2005] [Indexed: 10/25/2022]
Abstract
Lactobacillus johnsonii FI9785, a strain originally isolated from poultry gastrointestinal tract for its probiotic function as a competitive excluder of pathogens, was found to contain two cryptic plasmids of 3.5 and 25.6 kb. Nucleotide sequence analysis of the entire small plasmid, designated p9785S (3471 bp), indicated a G+C content of 35.8%, and revealed two open reading frames (orfs). The product of orf1 exhibited similarity to the relaxases of mobilizable plasmids, whereas the product of orf2 displayed significant homology to replication proteins of plasmids which use the rolling circle mode of replication. A conserved double-strand origin of replication was also present in p9785S. A definite minus origin was not identified although a region with extensive intrastrand base pairing potential was revealed. A 1.4 kb fragment encoding the chloramphenicol resistance gene was cloned into p9785S and the resulting vector, pFI2431, was stably maintained when introduced into the parent Lactobacillus cells.
Collapse
Affiliation(s)
- Nikki Horn
- Food Safety Science Division, Institute of Food Research, Norwich Research Park, Colney Lane, Norwich, Norfolk NR4 7UA, UK
| | | | | | | |
Collapse
|
15
|
Desmond C, Ross RP, Fitzgerald G, Stanton C. Sequence analysis of the plasmid genome of the probiotic strain Lactobacillus paracasei NFBC338 which includes the plasmids pCD01 and pCD02. Plasmid 2005; 54:160-75. [PMID: 15964627 DOI: 10.1016/j.plasmid.2005.04.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2004] [Revised: 03/22/2005] [Accepted: 04/04/2005] [Indexed: 11/23/2022]
Abstract
Lactobacillus paracasei NFBC338 is a probiotic strain that was isolated from the human gastrointestinal tract (GIT) and contains a plasmid genome of 80kb. Using a shotgun sequencing approach, two of the plasmids, pCD01 (19,882bp) and pCD02 (8554bp) have been completely sequenced, and four contiguous sequences (Contigs) have been assembled. Bioinformatic analysis of pCD01 revealed that it contains 23 putative open reading frames (ORFs) and that it contains regions characterised by potential replication functions and multidrug resistance (MDR). In contrast, the content of pCD02 is mainly cryptic, although, it does contain two insertion sequence (IS) elements. Indeed, up to 17% of the entire plasmid genome encodes putative transposable elements. In addition, there are a number of interesting ORFs distributed over the four Contigs that show significant homology to genes such as those involved in adherence and biotin metabolism, which may prove beneficial to Lb. paracasei NFBC338 under certain environmental conditions. This study provides a novel insight into the rich plasmid complement of this probiotic Lactobacillus strain, which may potentially be exploited as the basis for development of improved genetic tools for probiotic lactobacilli.
Collapse
Affiliation(s)
- C Desmond
- Teagasc, Biotechnology Centre, Moorepark, Fermoy, Co. Cork, Ireland; Department of Microbiology, University College, Cork, Ireland
| | | | | | | |
Collapse
|
16
|
Chang TLY, Chang CH, Simpson DA, Xu Q, Martin PK, Lagenaur LA, Schoolnik GK, Ho DD, Hillier SL, Holodniy M, Lewicki JA, Lee PP. Inhibition of HIV infectivity by a natural human isolate of Lactobacillus jensenii engineered to express functional two-domain CD4. Proc Natl Acad Sci U S A 2003; 100:11672-7. [PMID: 12972635 PMCID: PMC208816 DOI: 10.1073/pnas.1934747100] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The predominant mode of HIV transmission worldwide is via heterosexual contact, with the cervico-vaginal mucosa being the main portal of entry in women. The cervico-vaginal mucosa is naturally colonized with commensal bacteria, primarily lactobacilli. To address the urgent need for female-controlled approaches to block the heterosexual transmission of HIV, we have engineered natural human vaginal isolates of Lactobacillus jensenii to secrete two-domain CD4 (2D CD4) proteins. The secreted 2D CD4 recognized a conformation-dependent anti-CD4 antibody and bound HIV type 1 (HIV-1) gp120, suggesting that the expressed proteins adopted a native conformation. Single-cycle infection assays using HIV-1HxB2 carrying a luciferase reporter gene demonstrated that Lactobacillus-derived 2D CD4 inhibited HIV-1 entry into target cells in a dose-dependent manner. Importantly, coincubation of the engineered bacteria with recombinant HIV-1HxB2 reporter virus led to a significant decrease in virus infectivity of HeLa cells expressing CD4-CXCR4-CCR5. Engineered lactobacilli also caused a modest, but statistically significant, decrease in infectivity of a primary isolate, HIV-1JR-FL. This represents an important first step toward the development of engineered commensal bacteria within the vaginal microflora to inhibit heterosexual transmission of HIV.
Collapse
|