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Kleerebezem M, Bachmann H, van Pelt-KleinJan E, Douwenga S, Smid EJ, Teusink B, van Mastrigt O. Lifestyle, metabolism and environmental adaptation in Lactococcus lactis. FEMS Microbiol Rev 2021; 44:804-820. [PMID: 32990728 DOI: 10.1093/femsre/fuaa033] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 09/28/2020] [Indexed: 12/14/2022] Open
Abstract
Lactococcus lactis serves as a paradigm organism for the lactic acid bacteria (LAB). Extensive research into the molecular biology, metabolism and physiology of several model strains of this species has been fundamental for our understanding of the LAB. Genomic studies have provided new insights into the species L. lactis, including the resolution of the genetic basis of its subspecies division, as well as the control mechanisms involved in the fine-tuning of growth rate and energy metabolism. In addition, it has enabled novel approaches to study lactococcal lifestyle adaptations to the dairy application environment, including its adjustment to near-zero growth rates that are particularly relevant in the context of cheese ripening. This review highlights various insights in these areas and exemplifies the strength of combining experimental evolution with functional genomics and bacterial physiology research to expand our fundamental understanding of the L. lactis lifestyle under different environmental conditions.
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Affiliation(s)
- Michiel Kleerebezem
- Host-Microbe Interactomics Group, Animal Sciences Department, Wageningen University, De Elst 1, 6708 WD Wageningen, the Netherlands
| | - Herwig Bachmann
- Systems Bioinformatics, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ Amsterdam, the Netherlands.,NIZO food research, Kernhemseweg 2, 6718 ZB Ede, the Netherlands
| | - Eunice van Pelt-KleinJan
- Systems Bioinformatics, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ Amsterdam, the Netherlands.,TiFN Food & Nutrition, Nieuwe Kanaal 9A, 6709 PA Wageningen, the Netherlands
| | - Sieze Douwenga
- Systems Bioinformatics, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ Amsterdam, the Netherlands.,TiFN Food & Nutrition, Nieuwe Kanaal 9A, 6709 PA Wageningen, the Netherlands
| | - Eddy J Smid
- Laboratory of Food Microbiology, Wageningen University, Bornse Weilanden 9, 6708 WG Wageningen, the Netherlands
| | - Bas Teusink
- Systems Bioinformatics, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ Amsterdam, the Netherlands
| | - Oscar van Mastrigt
- Laboratory of Food Microbiology, Wageningen University, Bornse Weilanden 9, 6708 WG Wageningen, the Netherlands
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Engineer probiotic bifidobacteria for food and biomedical applications - Current status and future prospective. Biotechnol Adv 2020; 45:107654. [DOI: 10.1016/j.biotechadv.2020.107654] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 09/14/2020] [Accepted: 11/01/2020] [Indexed: 12/15/2022]
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Kok J, van Gijtenbeek LA, de Jong A, van der Meulen SB, Solopova A, Kuipers OP. The Evolution of gene regulation research in Lactococcus lactis. FEMS Microbiol Rev 2018; 41:S220-S243. [PMID: 28830093 DOI: 10.1093/femsre/fux028] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 06/15/2017] [Indexed: 11/12/2022] Open
Abstract
Lactococcus lactis is a major microbe. This lactic acid bacterium (LAB) is used worldwide in the production of safe, healthy, tasteful and nutritious milk fermentation products. Its huge industrial importance has led to an explosion of research on the organism, particularly since the early 1970s. The upsurge in the research on L. lactis coincided not accidentally with the advent of recombinant DNA technology in these years. The development of methods to take out and re-introduce DNA in L. lactis, to clone genes and to mutate the chromosome in a targeted way, to control (over)expression of proteins and, ultimately, the availability of the nucleotide sequence of its genome and the use of that information in transcriptomics and proteomics research have enabled to peek deep into the functioning of the organism. Among many other things, this has provided an unprecedented view of the major gene regulatory pathways involved in nitrogen and carbon metabolism and their overlap, and has led to the blossoming of the field of L. lactis systems biology. All of these advances have made L. lactis the paradigm of the LAB. This review will deal with the exciting path along which the research on the genetics of and gene regulation in L. lactis has trodden.
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Affiliation(s)
- Jan Kok
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, the Netherlands
| | - Lieke A van Gijtenbeek
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, the Netherlands
| | - Anne de Jong
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, the Netherlands
| | - Sjoerd B van der Meulen
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, the Netherlands
| | - Ana Solopova
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, the Netherlands
| | - Oscar P Kuipers
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, the Netherlands
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Synthetic biology in probiotic lactic acid bacteria: At the frontier of living therapeutics. Curr Opin Biotechnol 2018; 53:224-231. [PMID: 29550614 DOI: 10.1016/j.copbio.2018.01.028] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 12/22/2017] [Accepted: 01/24/2018] [Indexed: 12/19/2022]
Abstract
The trillions of microbes hosted by humans can dictate health or illness depending on a multitude of genetic, environmental, and lifestyle factors that help define the human ecosystem. As the human microbiota is characterized, so can the interconnectivity of microbe-host-disease be realized and manipulated. Designing microbes as therapeutic agents can not only enable targeted drug delivery but also restore homeostasis within a perturbed microbial community. Used for centuries in fermentation and preservation of food, lactic acid bacteria (LAB) have a long history of safe, and occasionally health promoting, interactions with the human gut, making them ideal candidates for engineered functionality. This review outlines available genetic tools, recent developments in biomedical applications, as well as potential future applications of synthetic biology to program LAB-based therapeutic systems.
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Abstract
Lactococcus lactis is one of the most commonly used lactic acid bacteria in the dairy industry. Activation of competence for natural DNA transformation in this species would greatly improve the selection of novel strains with desired genetic traits. Here, we investigated the activation of natural transformation in L. lactis subsp. cremoris KW2, a strain of plant origin whose genome encodes the master competence regulator ComX and the complete set of proteins usually required for natural transformation. In the absence of knowledge about competence regulation in this species, we constitutively overproduced ComX in a reporter strain of late competence phase activation and showed, by transcriptomic analyses, a ComX-dependent induction of all key competence genes. We further demonstrated that natural DNA transformation is functional in this strain and requires the competence DNA uptake machinery. Since constitutive ComX overproduction is unstable, we alternatively expressed comX under the control of an endogenous xylose-inducible promoter. This regulated system was used to successfully inactivate the adaptor protein MecA and subunits of the Clp proteolytic complex, which were previously shown to be involved in ComX degradation in streptococci. In the presence of a small amount of ComX, the deletion of mecA, clpC, or clpP genes markedly increased the activation of the late competence phase and transformability. Altogether, our results report the functionality of natural DNA transformation in L. lactis and pave the way for the identification of signaling mechanisms that trigger the competence state in this species.IMPORTANCE Lactococcus lactis is a lactic acid bacterium of major importance, which is used as a starter species for milk fermentation, a host for heterologous protein production, and a delivery platform for therapeutic molecules. Here, we report the functionality of natural transformation in L. lactis subsp. cremoris KW2 by the overproduction of the master competence regulator ComX. The developed procedure enables a flexible approach to modify the chromosome with single point mutation, sequence insertion, or sequence replacement. These results represent an important step for the genetic engineering of L. lactis that will facilitate the design of strains optimized for industrial applications. This will also help to discover natural regulatory mechanisms controlling competence in the genus Lactococcus.
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Jin Q, Li L, Kim Y, Han N. Construction of a dextran-free Leuconostoc citreum
mutant by targeted disruption of the dextransucrase gene. J Appl Microbiol 2014; 117:1104-12. [DOI: 10.1111/jam.12587] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 06/18/2014] [Accepted: 06/20/2014] [Indexed: 01/25/2023]
Affiliation(s)
- Q. Jin
- Department of Food Science; Yanbian University; Yanji Jilin China
| | - L. Li
- Brain Korea 21 Center for Bio-Resource Development; Division of Animal, Horticultural, and Food Sciences; Chungbuk National University; Cheongju Korea
| | - Y.J. Kim
- Department of Milk Processing Research Team; Korea Yakult; Youngin Korea
| | - N.S. Han
- Brain Korea 21 Center for Bio-Resource Development; Division of Animal, Horticultural, and Food Sciences; Chungbuk National University; Cheongju Korea
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Song L, Cui H, Tang L, Qiao X, Liu M, Jiang Y, Cui W, Li Y. Construction of upp deletion mutant strains of Lactobacillus casei and Lactococcus lactis based on counterselective system using temperature-sensitive plasmid. J Microbiol Methods 2014; 102:37-44. [DOI: 10.1016/j.mimet.2014.04.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 04/19/2014] [Accepted: 04/25/2014] [Indexed: 10/25/2022]
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Chen Y, Holtman CK, Taton A, Golden SS. Functional Analysis of the Synechococcus elongatus PCC 7942 Genome. FUNCTIONAL GENOMICS AND EVOLUTION OF PHOTOSYNTHETIC SYSTEMS 2012. [DOI: 10.1007/978-94-007-1533-2_5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Sela DA, Rawsthorne H, Mills DA. Characterization of the lactococcal group II intron target site in its native host. Plasmid 2007; 58:127-39. [PMID: 17408740 DOI: 10.1016/j.plasmid.2007.02.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2006] [Revised: 02/13/2007] [Accepted: 02/15/2007] [Indexed: 11/19/2022]
Abstract
The Lactococcus lactis group II intron (Ll.ltrB) retrohomes into the ltrB gene at high efficiency. To date, the critical DNA bases recognized in vivo by the Ll.ltrB ribonucleoprotein (RNP) have been exclusively elucidated in Escherichia coli. However, recent evidence indicates host-dependant differences in Ll.ltrB mobility, raising the possibility of limitations of the current model for RNP-homing site recognition in the native L. lactis host. In this work, intron retargeting experiments in L. lactis have demonstrated that adherence to specific target site critical bases is not sufficient to predict success or failure of chromosomal invasion, as in E. coli. Accordingly, a quantitative real-time PCR (QPCR) assay was developed to test target site nucleotides previously demonstrated as critical for homing in E. coli, for relevance in its native host. This two-plasmid QPCR homing assay is highly sensitive and, unlike previous E. coli-based assays, resolves differential homing efficiencies in the absence of selection. As in E. coli, deviation from wild type at target site positions -23, -21, -20, -19, and +5 resulted in lower homing efficiencies in L. lactis. Furthermore, the same trends are observed when assaying select variants in Enterococcus faecalis. Our results suggest that these target site positions are critical in both E. coli and L. lactis.
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Affiliation(s)
- David A Sela
- University of California at Davis, Department of Viticulture and Enology, One Shields Ave., Davis, CA 95616, USA
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Lambert JM, Bongers RS, Kleerebezem M. Cre-lox-based system for multiple gene deletions and selectable-marker removal in Lactobacillus plantarum. Appl Environ Microbiol 2006; 73:1126-35. [PMID: 17142375 PMCID: PMC1828656 DOI: 10.1128/aem.01473-06] [Citation(s) in RCA: 181] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The classic strategy to achieve gene deletion variants is based on double-crossover integration of nonreplicating vectors into the genome. In addition, recombination systems such as Cre-lox have been used extensively, mainly for eukaryotic organisms. This study presents the construction of a Cre-lox-based system for multiple gene deletions in Lactobacillus plantarum that could be adapted for use on gram-positive bacteria. First, an effective mutagenesis vector (pNZ5319) was constructed that allows direct cloning of blunt-end PCR products representing homologous recombination target regions. Using this mutagenesis vector, double-crossover gene replacement mutants could be readily selected based on their antibiotic resistance phenotype. In the resulting mutants, the target gene is replaced by a lox66-P(32)-cat-lox71 cassette, where lox66 and lox71 are mutant variants of loxP and P(32)-cat is a chloramphenicol resistance cassette. The lox sites serve as recognition sites for the Cre enzyme, a protein that belongs to the integrase family of site-specific recombinases. Thus, transient Cre recombinase expression in double-crossover mutants leads to recombination of the lox66-P(32)-cat-lox71 cassette into a double-mutant loxP site, called lox72, which displays strongly reduced recognition by Cre. The effectiveness of the Cre-lox-based strategy for multiple gene deletions was demonstrated by construction of both single and double gene deletions at the melA and bsh1 loci on the chromosome of the gram-positive model organism Lactobacillus plantarum WCFS1. Furthermore, the efficiency of the Cre-lox-based system in multiple gene replacements was determined by successive mutagenesis of the genetically closely linked loci melA and lacS2 in L. plantarum WCFS1. The fact that 99.4% of the clones that were analyzed had undergone correct Cre-lox resolution emphasizes the suitability of the system described here for multiple gene replacement and deletion strategies in a single genetic background.
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Affiliation(s)
- Jolanda M Lambert
- Wegeningen Centre for Food Science, Microbial Functionality and Safety Programme, Health and Safety Department, P.O. Box 20, 6710 BA Ede, The Netherlands
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Rawsthorne H, Turner KN, Mills DA. Multicopy integration of heterologous genes, using the lactococcal group II intron targeted to bacterial insertion sequences. Appl Environ Microbiol 2006; 72:6088-93. [PMID: 16957233 PMCID: PMC1563669 DOI: 10.1128/aem.02992-05] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Group II introns are mobile genetic elements that can be redirected to invade specific genes. Here we describe the use of the lactococcal group II intron, Ll.ltrB, to achieve multicopy delivery of heterologous genes into the genome of Lactococcus lactis IL1403-UCD without the need for selectable markers. Ll.ltrB was retargeted to invade three transposase genes, the tra gene found in IS904 (tra904), tra981, and tra983, of which 9, 10, and 14 copies, respectively, were present in IL1403-UCD. Intron invasion of tra904, tra981, and tra983 allele groups occurred at high frequencies, and individual segregants possessed anywhere from one to nine copies of intron in the respective tra alleles. To achieve multicopy delivery of a heterologous gene, a green fluorescent protein (GFP) marker was cloned into the tra904-targeted Ll.ltrB, and the resultant intron (Ll.ltrB::GFP) was induced to invade the L. lactis tra904 alleles. Segregants possessing Ll.ltrB::GFP in three, four, five, six, seven, and eight copies in different tra904 alleles were obtained. In general, increasing the chromosomal copy number of Ll.ltrB::GFP resulted in strains expressing successively higher levels of GFP. However, strains possessing the same number of Ll.ltrB::GFP copies within different sets of tra904 alleles exhibited differential GFP expression, and segregants possessing seven or eight copies of Ll.ltrB::GFP grew poorly upon induction, suggesting that GFP expression from certain combinations of alleles was detrimental. The highest level of GFP expression was observed from a specific six-copy variant that produced GFP at a level analogous to that obtained with a multicopy plasmid. In addition, the high level of GFP expression was stable for over 120 generations. This work demonstrates that stable multicopy integration of heterologous genes can be readily achieved in bacterial genomes with group II intron delivery by targeting repeated elements.
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Affiliation(s)
- Helen Rawsthorne
- University of California at Davis, Department of Viticulture and Enology, One Shields Ave., Davis, CA 95616, USA
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Mason CK, Collins MA, Thompson K. Modified electroporation protocol for Lactobacilli isolated from the chicken crop facilitates transformation and the use of a genetic tool. J Microbiol Methods 2005; 60:353-63. [PMID: 15649537 DOI: 10.1016/j.mimet.2004.10.013] [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: 03/25/2004] [Revised: 10/13/2004] [Accepted: 10/18/2004] [Indexed: 10/26/2022]
Abstract
Isolates of Lactobacillus spp. from a collection of potentially probiotic strains isolated from the crops of broiler chickens were found to be non-electrotransformable using published techniques. One strain of Lactobacillus salivarius was shown to develop electrocompetence when an overnight culture was incubated in fresh medium. The effect was enhanced if glycine was incorporated into the fresh growth medium. When these modifications were applied to a number of other crop isolates of Lactobacillus spp., electrocompetence could be detected in approximately half the strains tested. Two temperature sensitive plasmid vectors that had been used for the genetic modification of other lactic acid bacteria were introduced into a crop strain of Lb. salivarius. Both showed temperature sensitivity at 42 degrees C and above but were relatively stable at 37 degrees C. The genetic tool harbouring an IS element allowed the delivery of the plasmid to multiple independent sites in the host chromosome. Harnessing such genetic tools will facilitate the future genetic analysis of the host bacterium.
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Affiliation(s)
- Charlene K Mason
- Queen's University of Belfast, Newforge Lane, Belfast, BT9 5PX, Northern Ireland, UK
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Serror P, Ilami G, Chouayekh H, Ehrlich SD, Maguin E. Transposition in Lactobacillus delbrueckii subsp. bulgaricus: identification of two thermosensitive replicons and two functional insertion sequences. MICROBIOLOGY (READING, ENGLAND) 2003; 149:1503-1511. [PMID: 12777490 DOI: 10.1099/mic.0.25827-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In this report, it is shown that the rolling circle replicon pG(+)host and the theta replicon pIP501 are thermosensitive in Lactobacillus delbrueckii subsp. bulgaricus (Lactobacillus bulgaricus). Using a pIP501 derivative as a delivery vector for six insertion sequences originating from lactic acid bacteria, it is shown that IS1223 and IS1201 transpose in L. bulgaricus.
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Affiliation(s)
- Pascale Serror
- Unité Recherche Laitière et Génétique Appliquée, INRA, Domaine de Vilvert, 78352 Jouy-en-Josas Cedex, France
| | - Golnar Ilami
- Génétique Microbienne, INRA, Domaine de Vilvert, 78352 Jouy-en-Josas Cedex, France
| | - Hichem Chouayekh
- Génétique Microbienne, INRA, Domaine de Vilvert, 78352 Jouy-en-Josas Cedex, France
| | - S Dusko Ehrlich
- Génétique Microbienne, INRA, Domaine de Vilvert, 78352 Jouy-en-Josas Cedex, France
| | - Emmanuelle Maguin
- Génétique Microbienne, INRA, Domaine de Vilvert, 78352 Jouy-en-Josas Cedex, France
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Frazier CL, San Filippo J, Lambowitz AM, Mills DA. Genetic manipulation of Lactococcus lactis by using targeted group II introns: generation of stable insertions without selection. Appl Environ Microbiol 2003; 69:1121-8. [PMID: 12571038 PMCID: PMC143682 DOI: 10.1128/aem.69.2.1121-1128.2003] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Despite their commercial importance, there are relatively few facile methods for genomic manipulation of the lactic acid bacteria. Here, the lactococcal group II intron, Ll.ltrB, was targeted to insert efficiently into genes encoding malate decarboxylase (mleS) and tetracycline resistance (tetM) within the Lactococcus lactis genome. Integrants were readily identified and maintained in the absence of a selectable marker. Since splicing of the Ll.ltrB intron depends on the intron-encoded protein, targeted invasion with an intron lacking the intron open reading frame disrupted TetM and MleS function, and MleS activity could be partially restored by expressing the intron-encoded protein in trans. Restoration of splicing from intron variants lacking the intron-encoded protein illustrates how targeted group II introns could be used for conditional expression of any gene. Furthermore, the modified Ll.ltrB intron was used to separately deliver a phage resistance gene (abiD) and a tetracycline resistance marker (tetM) into mleS, without the need for selection to drive the integration or to maintain the integrant. Our findings demonstrate the utility of targeted group II introns as a potential food-grade mechanism for delivery of industrially important traits into the genomes of lactococci.
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Affiliation(s)
- Courtney L Frazier
- Department of Viticulture and Enology, University of California at Davis, Davis, California 95616-8749, USA
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Cotter PD, Hill C, Ross RP. A food-grade approach for functional analysis and modification of native plasmids in Lactococcus lactis. Appl Environ Microbiol 2003; 69:702-6. [PMID: 12514066 PMCID: PMC152420 DOI: 10.1128/aem.69.1.702-706.2003] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
While plasmids from lactic acid bacteria possess many traits that are of industrial value, their exploitation is often frustrated by an inability to conduct food-grade engineering of native plasmids or to readily screen for their transfer. Here we describe a system that uses a RepA(+) temperature-sensitive helper plasmid and a RepA(-) cloning vector to overcome these problems while maintaining the food-grade status of the native plasmid. This strategy was used to precisely delete ltnA1 alone, or in conjunction with ltnA2 (encoding the structural proteins of the lantibiotic lacticin 3147), from the native 60.2-kb plasmid pMRC01 and to select for the transfer of pMRC01 between Lactococcus lactis strains.
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Affiliation(s)
- Paul D Cotter
- Department of Microbiology and National Food Biotechnology Centre, University College Cork, Cork, Ireland
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16
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Current Awareness on Comparative and Functional Genomics. Comp Funct Genomics 2002. [PMCID: PMC2447281 DOI: 10.1002/cfg.118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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