<i>Lactococcus lactis</i>: high‐level expression of tetanus toxin fragment C and protection against lethal challenge

Wells, Jeremy M.; Wilson, Peter W.F.; Norton, Pamela M.; Gasson, Mike; Page, R.

doi:10.1111/j.1365-2958.1993.tb01660.x

Cited by 185 publications

(140 citation statements)

References 27 publications

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“…This plasmid, designated pIL1331, was replicative only in E. coli. Then, the EcoRI-HindIII fragment from pIL1331 was transferred to pMIG1 (39); the resulting plasmid, designated pIL1357, was replicative in L. lactis. Plasmids pWWT7 and pMIG1 were kindly provided by J. Wells.…”

Section: Methodsmentioning

confidence: 99%

“…A derivative, replicative in L. lactis, was constructed by cloning the EcoRI-HindIII fragment harboring the T7 RNA polymerase promoter in front of abiD1 from pIL1327 ( Fig. 1) into pMIG1 (39). The recombinant plasmid obtained was designated pIL1332.…”

Section: Methodsmentioning

confidence: 99%

“…The PCR product was cloned downstream of the T7 RNA polymerase promoter in plasmid pWWT7 in strain TG1. pWWT7 is a pUC18 derivative in which the HindIII-EcoRI T7 cassette from plasmid pLET1 (39) has been cloned (38a). The recombinant plasmid was designated pIL1327.…”

Section: Methodsmentioning

confidence: 99%

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Characterization of the lactococcal abiD1 gene coding for phage abortive infection

et al. 1995

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Lactococcal phage abortive infection (AbiD1) determined by plasmid pIL105 is active on both prolate-and small-isometric-head phages of the C6A and 936 phage groups, respectively, which are considered two different species. The Abi phenotype was found to be encoded by a single gene, designated abiD1. The abiD1-encoded protein (351 amino acids) does not show homology with any known protein and has a deduced isoelectric point of 10. It also possesses two helix-turn-helix structures and an unusually high content of asparagine, isoleucine, and lysine. A consensual promoter with a TGy extension to the ؊10 box was mapped 76 bp upstream of the start codon. Transcription initiated at this strong promoter stops at a terminator located 48 bp downstream from the promoter. The termination process is very efficient, and transcripts corresponding to the abiD1 gene were not visible in our experimental conditions with or without phage infection. Expression of abiD1 under the control of a T7 promoter induced a lag phase in Lactococcus lactis cell growth, suggesting that overproduction of AbiD1 could be toxic for the cells. AbiD1 protein was visualized in Escherichia coli by using a tightly controlled expression system.Lactococci are widely used for the manufacture of dairy products, where they are challenged with high concentrations of a variety of phages. Eleven different phage species have been defined according to DNA homology (18). These highly selective environmental conditions are most probably responsible for the selection of strains with a high degree of phage resistance. Some of these strains were shown to have accumulated several types of defense mechanisms, including adsorption interference, restriction and modification, and abortive infection (4,10,12,19). Therefore, lactococci represent a good model with which to study the coevolution of bacteria and phages and to identify phage defense mechanisms. One of these, abortive infection, abruptly interrupts phage development, resulting in the release of few or no progeny particles and cell death. This phenotype resembles that conferred by F on Escherichia coli infected by phage T7 (29). Three lactococcal genes coding for an Abi phenotype have been cloned and sequenced (6,7,10,16). The proteins specified by these genes, designated abiA, abiB, and abiC, have no homology with protein sequences in the data banks and are not cross-homologous. There is presently no hypothesis concerning their mode of action.In this work, we established that the Abi phenotype conferred by pIL105, previously shown to be active on lactococcal phages of two different species (12), is determined by a single gene, designated abiD1. Transcription initiated at a strong consensus promoter stops at a terminator located upstream of the gene. Transcripts corresponding to abiD1 were not detectable under our experimental conditions, indicating that the gene is expressed at a low level before or after phage infection. This may be due to some toxicity of the AbiD1 protein, suggested by a lag phase in the growth...

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Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

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Characterization of the lactococcal abiD1 gene coding for phage abortive infection

et al. 1995

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“…LAB is potential probiotics that provide benefits to human health [116]. Modified LAB could also be used as live vaccines or vaccine delivery systems [117]. It has been shown that the genetically modified L. lactis can survive and colonize the digestive tract of humans [118] and gnotobiotic mice [119].…”

Section: Discussionmentioning

confidence: 99%

The Microbiome of Spodoptera littoralis: Development, Control and Adaptation to the Insect Host

Mazumdar¹,

Teh²,

Boland³

2018

Metagenomics for Gut Microbes

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The symbiotic microbial consortium in the gut of Spodoptera littoralis shows dramatic, but reproducible changes in line with the development of the insect from the egg via six larval instars to the pupa. Since the food is kept constant during development, factors from the insect host and certain microbial symbionts are assumed to control the composition of the microbiome. A GFP-tagged Enterococcus mundtii, one of the major players of the consortium, easily integrates into the microbiome and can be monitored in all gut segments at all developmental stages. The reporter organism can be recovered from the gut using a preparative flow cytometry allowing subsequent RNA extraction for transcriptomic analyses. The transcriptomic profile from the fluorescent Enterococcus cells provides information on the adaptation of the reporter organism to the local gut conditions. The concept of using a fluorescent reporter organism that can be recovered at any time from any area of the intestinal tract will allow a holistic analysis of adaptation strategies used by the microbes to adapt to the insect gut. In combination with the analysis of transcript patterns from the gut membranes, a first insight into the molecular interaction between the insect host and the microbiome can be expected.

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“…It is generally recognized as safe by the U.S. Food and Drug Administration. Many heterologous proteins have been expressed in L. lactis (11,12,18,23,31,42,53), and immunization with these strains elicits immune responses specific to heterologous antigens (43,52,55). However, we are aware of only one report (55) that shows that mucosal immunization with a lactococcal vaccine can reduce infection.…”

mentioning

confidence: 91%

Mucosal Vaccine Made from Live, RecombinantLactococcus lactisProtects Mice against Pharyngeal Infection withStreptococcus pyogenes

2004

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A novel vaccine (LL-CRR) made from live, nonpathogenic Lactococcus lactis that expresses the conserved C-repeat region (CRR) of M protein from Streptococcus pyogenes serotype 6 was tested in mice. Nasally vaccinated mice produced CRR-specific salivary immunoglobulin A (IgA) and serum IgG. Subcutaneously vaccinated mice produced CRR-specific serum IgG but not salivary IgA. A combined regimen produced responses similar to the salivary IgA of nasally vaccinated mice and serum IgG of subcutaneously vaccinated mice. Mice vaccinated nasally or with the combined regimen were significantly protected against pharyngeal infection following a nasal challenge with S. pyogenes M serotype 14. Mice vaccinated subcutaneously were not protected against pharyngeal infection. Mice in all three LL-CRR vaccination groups were significantly protected against the lethal effects of S. pyogenes. Only 1 of 77 challenged mice that were vaccinated with LL-CRR died, whereas 60 of 118 challenged mice that were vaccinated with a control strain or phosphatebuffered saline died. In conclusion, mucosal vaccination with LL-CRR produced CRR-specific salivary IgA and serum IgG, prevented pharyngeal infection with S. pyogenes, and promoted survival.

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Lactococcus lactis: high‐level expression of tetanus toxin fragment C and protection against lethal challenge

Cited by 185 publications

References 27 publications

Characterization of the lactococcal abiD1 gene coding for phage abortive infection

Characterization of the lactococcal abiD1 gene coding for phage abortive infection

The Microbiome of Spodoptera littoralis: Development, Control and Adaptation to the Insect Host

Mucosal Vaccine Made from Live, RecombinantLactococcus lactisProtects Mice against Pharyngeal Infection withStreptococcus pyogenes

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