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1
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Yoshikawa S, Taniguchi K, Sawamura H, Ikeda Y, Tsuji A, Matsuda S. Advantageous tactics with certain probiotics for the treatment of graft-versus-host-disease after hematopoietic stem cell transplantation. World J Hematol 2023; 10:15-24. [DOI: 10.5315/wjh.v10.i2.15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 11/03/2022] [Accepted: 11/23/2022] [Indexed: 01/17/2023] Open
Abstract
Hematopoietic stem cell transplantation (HSCT) becomes a standard form of cellular therapy for patients with malignant diseases. HSCT is the first-choice of immunotherapy, although HSCT can be associated with many complications such as graft-versus-host disease (GVHD) which is a major cause of morbidity and mortality after allogeneic HSCT. It has been shown that certain gut microbiota could exert protective and/or regenerative immunomodulatory effects by the production of short-chain fatty acids (SCFAs) such as butyrate in the experimental models of GVHD after allogeneic HSCT. Loss of gut commensal bacteria which can produce SCFAs may worsen dysbiosis, increasing the risk of GVHD. Expression of G-protein coupled receptors such as GPR41 seems to be upre-gulated in the presence of commensal bacteria, which might be associated with the biology of regulatory T cells (Tregs). Treg cells are a suppressive subset of CD4 positive T lymphocytes implicated in the prevention of GVHD after allogeneic HSCT. Here, we discuss the current findings of the relationship between the modification of gut microbiota and the GVHD-related immunity, which suggested that tactics with certain probiotics for the beneficial symbiosis in gut-immune axis might lead to the elevation of safety in the allogeneic HSCT.
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Affiliation(s)
- Sayuri Yoshikawa
- Food Science and Nutrition, Nara Women's University, Nara 630-8506, Japan
| | - Kurumi Taniguchi
- Food Science and Nutrition, Nara Women's University, Nara 630-8506, Japan
| | - Haruka Sawamura
- Food Science and Nutrition, Nara Women's University, Nara 630-8506, Japan
| | - Yuka Ikeda
- Food Science and Nutrition, Nara Women's University, Nara 630-8506, Japan
| | - Ai Tsuji
- Food Science and Nutrition, Nara Women's University, Nara 630-8506, Japan
| | - Satoru Matsuda
- Food Science and Nutrition, Nara Women's University, Nara 630-8506, Japan
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2
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Ikeda Y, Taniguchi K, Sawamura H, Tsuji A, Matsuda S. Promising role of D-amino acids in irritable bowel syndrome. World J Gastroenterol 2022; 28:4471-4474. [PMID: 36159020 PMCID: PMC9453761 DOI: 10.3748/wjg.v28.i31.4471] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 06/14/2022] [Accepted: 07/22/2022] [Indexed: 02/06/2023] Open
Abstract
Irritable bowel syndrome (IBS) is an important health care concern. Alterations in the microbiota of the gut-brain axis may be linked to the pathophysiology of IBS. Some dietary intake could contribute to produce various metabolites including D-amino acids by the fermentation by the gut microbiota. D-amino acids are the enantiomeric counterparts of L-amino acids, in general, which could play key roles in cellular physiological processes against various oxidative stresses. Therefore, the presence of D-amino acids has been shown to be linked to the protection of several organs in the body. In particular, the gut microbiota could play significant roles in the stability of emotion via the action of D-amino acids. Here, we would like to shed light on the roles of D-amino acids, which could be used for the treatment of IBS.
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Affiliation(s)
- Yuka Ikeda
- Department of Food Science and Nutrition, Nara Women's University, Nara 630-8506, Japan
| | - Kurumi Taniguchi
- Department of Food Science and Nutrition, Nara Women's University, Nara 630-8506, Japan
| | - Haruka Sawamura
- Department of Food Science and Nutrition, Nara Women's University, Nara 630-8506, Japan
| | - Ai Tsuji
- Department of Food Science and Nutrition, Nara Women's University, Nara 630-8506, Japan
| | - Satoru Matsuda
- Department of Food Science and Nutrition, Nara Women's University, Nara 630-8506, Japan
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3
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Nagase N, Ikeda Y, Tsuji A, Kitagishi Y, Matsuda S. Efficacy of probiotics on the modulation of gut microbiota in the treatment of diabetic nephropathy. World J Diabetes 2022; 13:150-160. [PMID: 35432750 PMCID: PMC8984564 DOI: 10.4239/wjd.v13.i3.150] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 05/21/2021] [Accepted: 02/13/2022] [Indexed: 02/06/2023] Open
Abstract
Diabetic nephropathy (DN) is a major cause of end-stage renal disease, and therapeutic options for preventing its progression are insufficient. The number of patients with DN has been increasing in Asian countries because of westernization of dietary lifestyle, which may be associated with the following changes in gut microbiota. Alterations in the gut microbiota composition can lead to an imbalanced gastrointestinal environment that promotes abnormal production of metabolites and/or inflammatory status. Functional microenvironments of the gut could be changed in the different stages of DN. In particular, altered levels of short chain fatty acids, D-amino acids, and reactive oxygen species biosynthesis in the gut have been shown to be relevant to the pathogenesis of the DN. So far, evidence suggests that the gut microbiota may play a key role in determining networks in the development of DN. Interventions directing the gut microbiota deserve further investigation as a new protective therapy in DN. In this review, we discuss the potential roles of the gut microbiota and future perspectives in the protection and/or treatment of kidneys.
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Affiliation(s)
- Nozomi Nagase
- Department of Food Science and Nutrition, Nara Women's University, Nara 630-8506, Japan
| | - Yuka Ikeda
- Department of Food Science and Nutrition, Nara Women's University, Nara 630-8506, Japan
| | - Ai Tsuji
- Department of Food Science and Nutrition, Nara Women's University, Nara 630-8506, Japan
| | - Yasuko Kitagishi
- Department of Food Science and Nutrition, Nara Women's University, Nara 630-8506, Japan
| | - Satoru Matsuda
- Department of Food Science and Nutrition, Nara Women's University, Nara 630-8506, Japan
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Flynn J, Ryan A, Hudson SP. Pre-formulation and delivery strategies for the development of bacteriocins as next generation antibiotics. Eur J Pharm Biopharm 2021; 165:149-163. [PMID: 34020021 DOI: 10.1016/j.ejpb.2021.05.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 05/06/2021] [Accepted: 05/12/2021] [Indexed: 10/21/2022]
Abstract
Bacteriocins, a class of antimicrobial peptide produced by bacteria, may offer a potential alternative to traditional antibiotics, an important step towards mitigating the ever-increasing antimicrobial resistance crisis. They are active against a range of clinically relevant Gram-positive and Gram-negative bacteria. Bacteriocins have been discussed in the literature for over a century. Although they are used as preservatives in food, no medicine based on their antimicrobial activity exists on the market today. In order to formulate them into clinical antibiotics, pre-formulation studies on their biophysical and physicochemical properties that will influence their activity in vivo and their stability during manufacture must be elucidated. Thermal, pH and enzymatic stability of bacteriocins are commonly studied and regularly reported in the literature. Solubility, permeability and aggregation properties on the other hand are less frequently reported for many bacteriocins, which may contribute to their poor clinical progression. Promising cytotoxicity studies report that bacteriocins exhibit few cytotoxic effects on a variety of mammalian cell lines, at active concentrations. This review highlights the lack of quantitative data and in many cases even qualitative data, on bacteriocins' solubility, stability, aggregation, permeability and cytotoxicity. The formulation strategies that have been explored to date, proposed routes of administration, trends in in vitro/in vivo behaviour and efforts in clinical development are discussed. The future promise of bacteriocins as a new generation of antibiotics may require tailored local delivery strategies to fulfil their potential as a force to combat antimicrobial-resistant bacterial infections.
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Affiliation(s)
- James Flynn
- Department of Chemical Sciences, SSPC, the SFI Research Centre for Pharmaceuticals, Bernal Institute, University of Limerick, Ireland
| | - Aoibhín Ryan
- Department of Chemical Sciences, SSPC, the SFI Research Centre for Pharmaceuticals, Bernal Institute, University of Limerick, Ireland
| | - Sarah P Hudson
- Department of Chemical Sciences, SSPC, the SFI Research Centre for Pharmaceuticals, Bernal Institute, University of Limerick, Ireland.
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5
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Taniguchi K, Ikeda Y, Nagase N, Tsuji A, Kitagishi Y, Matsuda S. Implications of Gut-Brain axis in the pathogenesis of Psychiatric disorders. AIMS BIOENGINEERING 2021. [DOI: 10.3934/bioeng.2021021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
<abstract>
<p>Psychiatric disorders may extremely impair the quality of life with patients and are important reasons of social disability. Several data have shown that psychiatric disorders are associated with an altered composition of gut microbiota. Dietary intake could determine the microbiota, which contribute to produce various metabolites of fermentation such as short chain fatty acids. Some of the metabolites could result in epigenetic alterations leading to the disease susceptibility. Epigenetic dysfunction is in fact implicated in various psychiatric and neurologic disorders. For example, it has been shown that neuroepigenetic dysregulation occurs in psychiatric disorders including schizophrenia. Several studies have demonstrated that the intestinal microbiome may influence the function of central nervous system. Furthermore, it has been proved that the alterations in the gut microbiota-composition might affect in the bidirectional communication between gut and brain. Similarly, evidences demonstrating the association between psychiatric disorders and the gut microbiota have come from preclinical studies. It is clear that an intricate symbiotic relationship might exist between host and microbe, although the practical significance of the gut microbiota has not yet to be determined. In this review, we have summarized the function of gut microbiota in main psychiatric disorders with respect to the mental health. In addition, we would like to discuss the potential mechanisms of the disorders for the practical diagnosis and future treatment by using bioengineering of microbiota and their metabolites.</p>
</abstract>
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Janßen D, Dworschak L, Ludwig C, Ehrmann MA, Vogel RF. Interspecies assertiveness of Lactobacillus curvatus and Lactobacillus sakei in sausage fermentations. Int J Food Microbiol 2020; 331:108689. [PMID: 32623291 DOI: 10.1016/j.ijfoodmicro.2020.108689] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 05/18/2020] [Accepted: 05/24/2020] [Indexed: 12/25/2022]
Abstract
Lactobacillus (L.) curvatus and L. sakei contain strains, which are assertive in sausage fermentation. Previous work has demonstrated differences in assertiveness at strain level within one species, and revealed either exclusion of competitors by complementary partner strains or their inhibition by single strains. This work addresses interspecies differences in the assertiveness of L. curvatus and L. sakei. Strain sets of L. curvatus and L. sakei were employed as starters in a fermented sausage model and their abundancy upon fermentation was determined by strain-specific MALDI-TOF MS identification. Generally, single or groups of L. sakei strains outcompeted L. curvatus strains. In multiple growth tests employing mMRS and mMSM it could be shown that assertive L. sakei strains can be predicted along their μ max in mMSM. Still, L. curvatus TMW 1.624 could suppress all L. curvatus and most L. sakei strains in competitive settings. This could be referred to its expression of several bacteriocins, which are active against all of the L. curvatus strains. Strain specific differences could be demonstrated in the susceptibility of L. sakei to bacteriocins, and in oxidative stress tolerance, which is higher in co-existing L. sakei strains than in the bacteriocin producer. This suggests that tolerance to bacteriocins and oxidative stress represent additional determinants for assertiveness, above previously reported bacteriocin production versus metabolic complementarism of partner strains.
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Affiliation(s)
- Dorothee Janßen
- Technische Universität München, Lehrstuhl für Technische Mikrobiologie, Freising, Germany
| | - Lena Dworschak
- Technische Universität München, Lehrstuhl für Technische Mikrobiologie, Freising, Germany
| | - Christina Ludwig
- Bayerisches Zentrum für biomolekulare Massenspektrometrie (BayBioMS), Technische Universität München, Freising, Germany
| | - Matthias A Ehrmann
- Technische Universität München, Lehrstuhl für Technische Mikrobiologie, Freising, Germany
| | - Rudi F Vogel
- Technische Universität München, Lehrstuhl für Technische Mikrobiologie, Freising, Germany.
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7
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Moll GN, Kuipers A, Rink R. Microbial engineering of dehydro-amino acids and lanthionines in non-lantibiotic peptides. Antonie van Leeuwenhoek 2010; 97:319-33. [PMID: 20140513 DOI: 10.1007/s10482-010-9418-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2009] [Accepted: 01/25/2010] [Indexed: 10/19/2022]
Abstract
This minireview focuses on the use of bacteria to introduce dehydroresidues and (methyl)lanthionines in (poly)peptides. It mainly describes the broad exploitation of bacteria containing lantibiotic enzymes for the engineering of these residues in a wide variety of peptides in particular in peptides unrelated to lantibiotics. Lantibiotic dehydratases dehydrate serines and threonines present in peptides preceded by a lantibiotic leader peptide thus forming dehydroalanine and dehydrobutyrine, respectively. These dehydroresidues can be coupled to cysteines thus forming (methyl)lanthionines. This coupling is catalysed by lantibiotic cyclases. The design, synthesis, and export of microbially engineered dehydroresidue and or lanthionine-containing peptides in non-lantibiotic peptides are reviewed, illustrated by some examples which demonstrate the high relevance of these special residues. This minireview is the first with special focus on the microbial engineering of nonlantibiotic peptides by exploiting lantibiotic enzymes.
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Affiliation(s)
- Gert N Moll
- BiOMaDe Technology Foundation, Nijenborgh 4, Groningen, The Netherlands.
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8
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Dufour A, Hindré T, Haras D, Le Pennec JP. The biology of lantibiotics from the lacticin 481 group is coming of age. FEMS Microbiol Rev 2006; 31:134-67. [PMID: 17096664 DOI: 10.1111/j.1574-6976.2006.00045.x] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Lantibiotics are antimicrobial peptides from the bacteriocin family, secreted by Gram-positive bacteria. These peptides differ from other bacteriocins by the presence of (methyl)lanthionine residues, which result from enzymatic modification of precursor peptides encoded by structural genes. Several groups of lantibiotics have been distinguished, the largest of which is the lacticin 481 group. This group consists of at least 16 members, including lacticin 481, streptococcin A-FF22, mutacin II, nukacin ISK-1, and salivaricins. We present the first review devoted to this lantibiotic group, knowledge of which has increased significantly within the last few years. After updating the group composition and defining the common properties of these lantibiotics, we highlight the most recent developments. The latter concern: transcriptional regulation of the lantibiotic genes; understanding the biosynthetic machinery, in particular the ability to perform in vitro prepeptide maturation; characterization of a novel type of immunity protein; and broad application possibilities. This group differs in many aspects from the best known lantibiotic group (nisin group), but shares properties with less-studied groups such as the mersacidin, cytolysin and lactocin S groups.
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Affiliation(s)
- Alain Dufour
- Laboratoire de Biotechnologie et Chimie Marines, EA3884, Université de Bretagne Sud, Lorient, France.
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9
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Chatterjee C, Paul M, Xie L, van der Donk WA. Biosynthesis and mode of action of lantibiotics. Chem Rev 2005; 105:633-84. [PMID: 15700960 DOI: 10.1021/cr030105v] [Citation(s) in RCA: 563] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Champak Chatterjee
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois, USA
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10
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Bekal-Si Ali S, Hurtubise Y, Lavoie MC, LaPointe G. Diversity of Streptococcus mutans bacteriocins as confirmed by DNA analysis using specific molecular probes. Gene 2002; 283:125-31. [PMID: 11867219 DOI: 10.1016/s0378-1119(01)00875-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Mutacin-producing strains have been classified into 24 groups (designated by letters A to X) by similarity in activity spectra and cross-immunity. Similarity in primary structure among these groups can be revealed using DNA hybridization. The amino acid sequences of four mutacins (B-Ny266, 1140/mutacin III and mutacin II) were used to design two DNA probes in order to detect similar genes among groups of Streptococcus mutans strains demonstrating inhibitory activity. In addition to the appropriate parent strain, each probe hybridized with the total DNA from only two out of the 24 mutacin group type strains. Thus, the remaining 18 groups of strains produce mutacins that differ from the mutacins sequenced to date. In order to explore the similarity between genes coding for mutacins B-Ny266 and JH1140, the group B specific probe was utilized to detect a DNA fragment of 1.9 kb in the genome of S. mutans strain Ny266. The sequence of the cloned fragment codes for three open reading frames (lanA, lanA' and lanB) similar to those of strains JH1140 and UA787. The gene lanA' is strongly similar to the structural gene lanA (67%), but only one RNA transcript of about 300 bases was detected by Northern hybridization using the lanA-lanA' probe. Transcription of lanA alone was verified by RT-PCR.
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11
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Abstract
The lantibiotics are a group of ribosomally synthesised, post-translationally modified peptides containing unusual amino acids, such as dehydrated and lanthionine residues. This group of bacteriocins has attracted much attention in recent years due to the success of the well characterised lantibiotic, nisin, as a food preservative. Numerous other lantibiotics have since been identified and can be divided into two groups on the basis of their structures, designated type-A and type-B. To date, many of these lantibiotics have undergone extensive characterisation resulting in an advanced understanding of them at both the structural and mechanistic level. This review outlines some of the more recent developments in the biochemistry, genetics and mechanism of action of these peptides.
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Affiliation(s)
- O McAuliffe
- Department of Microbiology, University College Cork, Ireland
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12
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Abstract
Bacterial-derived antimicrobial polypeptides enjoy a large degree of structural and chemical diversity. Two well-studied examples of such polypeptides are the lanthionine-containing lantibiotics produced by a variety of Gram-positive bacteria, and their Gram-negative counterparts, the microcins. Both groups are produced as gene-encoded precursor peptides and undergo post-translational modification to generate the active moieties. Structure elucidation of novel lantibiotics and microcins has recently uncovered further novel structural and chemical features and, combined with the generation of analogue peptides by genetic manipulation, new insights into structure-function relationships have been gained. Furthermore, study of the mode of action of the lantibiotics nisin and mersacidin has revealed their use of a 'docking molecule' in the target cell to facilitate their biological activities. Meanwhile, in vitro studies with microcin B17 have helped to uncover the molecular mechanisms by which post-translational modification results in the formation of heterocyclic oxazole and thiazole rings. From a practical standpoint, both groups of polypeptides represent new lead structures for future development of antimicrobial agents, whilst the identification of the 'docking molecules' represents a step forward in the search for novel targets for future antibiosis.
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Affiliation(s)
- R W Jack
- Institut für Organische Chemie, der Universität Tübingen, EMC microcollections GmbH, Tübingen, 72076, 72070, Germany.
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McAuliffe O, Hill C, Ross RP. Identification and overexpression of ltnl, a novel gene which confers immunity to the two-component lantibiotic lacticin 3147. MICROBIOLOGY (READING, ENGLAND) 2000; 146 ( Pt 1):129-138. [PMID: 10658659 DOI: 10.1099/00221287-146-1-129] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Production and immunity of the two-component lantibiotic lacticin 3147 is encoded by the 60-2 kb lactococcal plasmid pMRC01. A 12.6 kb region of this plasmid, containing ten genes in two divergently arranged gene clusters, has been subcloned in Lactococcus lactis subsp. cremoris MG1363 and has been shown to confer both lacticin 3147 production and immunity. Further subcloning revealed that the smaller of the two clusters (ItnRIFE) confers immunity. Although the ItnF and E genes are homologous to ABC transporters which confer immunity to other lantibiotics, deletion analysis indicates that they do not play a role in the immunity exhibited by this subclone in L. lactis subsp. cremoris MG1363. Also, a deletion in ItnR (which resembles a family of transcriptional repressors) had no effect on immunity. The remaining gene, Itnl, encodes a 116 amino acid protein with a predicted membrane location which bears no homology to other bacteriocin immunity proteins. Confirmation of its role in immunity was obtained when it was observed that disruption of Itnl resulted in a complete loss of immunity. When Itnl was cloned into the expression vector pMG36e, the resulting construct conferred levels of immunity comparable to pMRC01. This confirmed that under the control of a strong promoter, the Itnl gene product alone is sufficient to confer lacticin immunity. In addition, heterologous expression of Itnl was observed in Enterococcus faecalis OG1X. On cloning Itnl behind a nisin-inducible promoter, it was observed that the level of immunity was dependent on nisin concentration. Using this construct, the authors have demonstrated a potential role for Itnl as food-grade selectable marker. Thus, Ltnl appears to represent a new class of lantibiotic immunity proteins.
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Affiliation(s)
- Olivia McAuliffe
- Department of Microbiology and National Food Biotechnology Centre, University College Cork, Republic of Ireland1
| | - Colin Hill
- Department of Microbiology and National Food Biotechnology Centre, University College Cork, Republic of Ireland1
| | - R Paul Ross
- National Dairy Products Research Centre, Moorepark, Fermoy, Co. Cork, Republic of Ireland2
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14
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Qi F, Chen P, Caufield PW. Functional analyses of the promoters in the lantibiotic mutacin II biosynthetic locus in Streptococcus mutans. Appl Environ Microbiol 1999; 65:652-8. [PMID: 9925596 PMCID: PMC91075 DOI: 10.1128/aem.65.2.652-658.1999] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/1998] [Accepted: 11/17/1998] [Indexed: 02/02/2023] Open
Abstract
The lantibiotic bacteriocin mutacin II is produced by the group II Streptococcus mutans. The mutacin II biosynthetic locus consists of seven genes, mutR, -A, -M, -T, -F, -E, and -G, organized as two operons. The mutAMTFEG operon is transcribed from the mutA promoter 55 bp upstream of the translation start codon for MutA, while the mutR promoter is 76 bp upstream of the mutR structural gene. Expression of the mutA promoter is regulated by the components of the growth medium, while the mutR promoter activity does not seem to be affected by these conditions. Inactivation of mutR abolishes transcription of the mutA operon but does not affect its own promoter activity. The expressions of both mutA and mutR promoters are independent of the growth stage, while the production of mutacin II is only elevated at the early stationary phase. Taken together, these results suggest that expression of the mutacin operon is regulated by a complex system involving transcriptional and posttranscriptional or posttranslational controls.
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Affiliation(s)
- F Qi
- Department of Oral Biology, School of Dentistry, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA.
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15
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Navaratna MA, Sahl HG, Tagg JR. Two-component anti-Staphylococcus aureus lantibiotic activity produced by Staphylococcus aureus C55. Appl Environ Microbiol 1998; 64:4803-8. [PMID: 9835565 PMCID: PMC90925 DOI: 10.1128/aem.64.12.4803-4808.1998] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Staphylococcus aureus C55 was shown to produce bacteriocin activity comprising three distinct peptide components, termed staphylococcins C55alpha, C55beta, and C55gamma. The three peptides were purified to homogeneity by a simple four-step purification procedure that consisted of ammonium sulfate precipitation followed by XAD-2 and reversed-phase (C8 and C18) chromatography. The yield following C8 chromatography was about 86%, with a more-than-300-fold increase in specific activity. When combined in approximately equimolar amounts, staphylococcins C55alpha and C55beta acted synergistically to kill S. aureus or Micrococcus luteus but not S. epidermidis strains. The N-terminal amino acid sequences of all three peptides were obtained and staphylococcins C55alpha and C55beta were shown to be lanthionine-containing (lantibiotic) molecules with molecular weights of 3,339 and 2,993, respectively. The C55gamma peptide did not appear to be a lantibiotic, nor did it augment the inhibitory activities of staphylococcin C55alpha and/or C55beta. Plasmids of 2. 5 and 32.0 kb are present in strain C55, and following growth of this strain at elevated temperature (42 degreesC), a large proportion of the progeny failed to produce strong bacteriocin activity and also lost the 32.0-kb plasmid. Protoplast transformation of these bacteria with purified 32-kb plasmid DNA regenerates the ability to produce the strong bacteriocin activity.
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Affiliation(s)
- M A Navaratna
- Department of Microbiology, University of Otago, Dunedin, New Zealand
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