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Man LL, Xiang DJ. Effect of LuxS/AI-2-mediated quorum sensing system on bacteriocin production of Lactobacillus plantarum NMD-17. Folia Microbiol (Praha) 2023; 68:855-866. [PMID: 37156969 DOI: 10.1007/s12223-023-01060-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 04/21/2023] [Indexed: 05/10/2023]
Abstract
Lactobacillus plantarum NMD-17 separated from koumiss could produce a bacteriocin named plantaricin MX against Gram-positive bacteria and Gram-negative bacteria. The bacteriocin synthesis of L. plantarum NMD-17 was remarkably induced in co-cultivation with Lactobacillus reuteri NMD-86 as the increase of cell numbers and AI-2 activity, and the expressions of luxS encoding signal AI-2 synthetase, plnB encoding histidine protein kinase, plnD encoding response regulator, and plnE and plnF encoding structural genes of bacteriocin were significantly upregulated in co-cultivation, showing that the bacteriocin synthesis of L. plantarum NMD-17 in co-cultivation may be regulated by LuxS/AI-2-mediated quorum sensing system. In order to further demonstrate the role of LuxS/AI-2-mediated quorum sensing system in the bacteriocin synthesis of L. plantarum NMD-17, plasmids pUC18 and pMD18-T simple were used as the skeleton to construct the suicide plasmids pUC18-UF-tet-DF and pMD18-T simple-plnB-tet-plnD for luxS and plnB-plnD gene deletion, respectively. luxS and plnB-plnD gene knockout mutants were successfully obtained by homologous recombination. luxS gene knockout mutant lost its AI-2 synthesis ability, suggesting that LuxS protein encoded by luxS gene is key enzyme for AI-2 synthesis. plnB-plnD gene knockout mutant lost the ability to synthesize bacteriocin against Salmonella typhimurium ATCC14028, indicating that plnB-plnD gene was a necessary gene for bacteriocin synthesis of L. plantarum NMD-17. Bacteriocin synthesis, cell numbers, and AI-2 activity of luxS or plnB-plnD gene knockout mutants in co-cultivation with L. reuteri NMD-86 were obviously lower than those of wild-type strain in co-cultivation at 6-9 h (P < 0.01). The results showed that LuxS/AI-2-mediated quorum sensing system played an important role in the bacteriocin synthesis of L. plantarum NMD-17 in co-cultivation.
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Affiliation(s)
- Li-Li Man
- College of Life Sciences and Food Engineering, Inner Mongolia Minzu University, Tongliao, 028042, People's Republic of China
| | - Dian-Jun Xiang
- College of Agriculture, Inner Mongolia Minzu University, Tongliao, 028042, People's Republic of China.
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2
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Yu L, Chen Y, Duan H, Qiao N, Wang G, Zhao J, Zhai Q, Tian F, Chen W. Latilactobacillus sakei: a candidate probiotic with a key role in food fermentations and health promotion. Crit Rev Food Sci Nutr 2022; 64:978-995. [PMID: 35997270 DOI: 10.1080/10408398.2022.2111402] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Latilactobacillus sakei is used extensively in industrial production and food fermentations. The species is primarily derived from fermented meat and vegetable products and is also found in human feces. Genomics and metabolomics have revealed unique metabolic pathways in L. sakei and molecular mechanisms underlying its competitive advantages in different habitats, which are mostly attributed to its flexible carbohydrate metabolism, cold tolerance, acid and salt tolerance, ability to cope with oxygen changes, and heme uptake. In recent years, probiotic effects of L. sakei and its metabolites have been identified, including the ability to effectively alleviate metabolic syndrome, inflammatory bowel disease, and atopic dermatitis. This review summarizes the genomic and metabolic characteristics of L. sakei and its metabolites and describes their applications, laying a foundation for their expanded use across the food and healthcare industries.
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Affiliation(s)
- Leilei Yu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
- International Joint Research Laboratory for Probiotics at Jiangnan University, Wuxi, Jiangsu, China
| | - Ying Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
| | - Hui Duan
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
- National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu, China
| | - Nanzhen Qiao
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Gang Wang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
- National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu, China
| | - Jianxin Zhao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
- International Joint Research Laboratory for Probiotics at Jiangnan University, Wuxi, Jiangsu, China
- National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu, China
| | - Qixiao Zhai
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
- International Joint Research Laboratory for Probiotics at Jiangnan University, Wuxi, Jiangsu, China
| | - Fengwei Tian
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
- International Joint Research Laboratory for Probiotics at Jiangnan University, Wuxi, Jiangsu, China
| | - Wei Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
- International Joint Research Laboratory for Probiotics at Jiangnan University, Wuxi, Jiangsu, China
- National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu, China
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3
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Mathiesen G, Axelsson L, Eijsink VGH. Heterologous Protein Production in Lactobacillus (plantarum) Using pSIP Vectors. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2022; 2406:205-217. [PMID: 35089559 DOI: 10.1007/978-1-0716-1859-2_12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
While lactobacilli are not generally regarded as efficient cell factories for heterologous proteins, these food-grade Gram-positive bacteria are attractive as expression hosts for medicinal proteins. Furthermore, tools have been developed not only to secrete the protein of interest, but also to anchor the protein to the cell membrane or the cell wall. Research efforts aimed at the production and surface display of complex vaccine proteins have shown that lactobacilli are capable of producing heterologous proteins that are otherwise difficult to produce in soluble form. Many recent studies on expressing a wide variety of proteins in lactobacilli have employed the pSIP vector system, which offers a wide range of possibilities for inducible expression, including various options for secretion and surface anchoring. The modular nature of the pSIP vectors allows for rapid screening of multiple expression strategies. This chapter describes the pSIP vector system and how it can be used to accomplish protein expression in lactobacilli.
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Affiliation(s)
- Geir Mathiesen
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Lars Axelsson
- Nofima AS, Norwegian Institute of Food, Fisheries and Aquaculture Research, Ås, Norway
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway.
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4
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Najjari A, Boumaiza M, Jaballah S, Boudabous A, Ouzari H. Application of isolated Lactobacillus sakei and Staphylococcus xylosus strains as a probiotic starter culture during the industrial manufacture of Tunisian dry-fermented sausages. Food Sci Nutr 2020; 8:4172-4184. [PMID: 32884698 PMCID: PMC7455971 DOI: 10.1002/fsn3.1711] [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: 03/26/2020] [Revised: 05/21/2020] [Accepted: 05/22/2020] [Indexed: 12/13/2022] Open
Abstract
For decades, lactic acid bacteria has been isolated and selected to be used as starter cultures in meat fermentation for standardization and management of quality of dry-fermented sausage which constitute a considerable challenge. The aim of this study was to evaluate the effect of Lactobacillus sakei strains, isolated from different origins, on qualities of dry-fermented sausages. These last, manufactured with different combinations of starter cultures (L. sakei + Staphylococcus xylosus), were ripened, using the same raw materials and conditions, for 45 days. Samples were collected during this period, and microbiological, physicochemical, fatty acid profile, and sensorial analyses determined. Lactic acid bacteria were the dominant flora during ripening. A desirable PUFA/SFA ratio, corresponding to 1:1.7 (0.6), was detected after 24 days of maturation in sausages inoculated by L. sakei BMG 95 and S. xylosus. Sensory analysis showed that fermented sausages manufactured with L. sakei and S. xylosus had a more desirable odor, flavor, and texture and consequently were preferred overall. In particular, sensory panellists preferred sausages produced with either L. sakei 23K or L. sakei BMG 95 when compared to fermented sausage produced with a commercial starter or no starter at all.
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Affiliation(s)
- Afef Najjari
- Faculté des Sciences de TunisLR03ES03 Microorganismes et Biomolécules ActivesUniversité de Tunis El ManarTunisTunisia
| | - Mohamed Boumaiza
- Faculté des Sciences de TunisLR03ES03 Microorganismes et Biomolécules ActivesUniversité de Tunis El ManarTunisTunisia
| | - Sana Jaballah
- Faculté des Sciences de TunisLR03ES03 Microorganismes et Biomolécules ActivesUniversité de Tunis El ManarTunisTunisia
| | - Abdelatif Boudabous
- Faculté des Sciences de TunisLR03ES03 Microorganismes et Biomolécules ActivesUniversité de Tunis El ManarTunisTunisia
| | - Hadda‐Imene Ouzari
- Faculté des Sciences de TunisLR03ES03 Microorganismes et Biomolécules ActivesUniversité de Tunis El ManarTunisTunisia
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Tse TJ, Shen J, Shim YY, Reaney MJT. Changes in Bacterial Populations and Their Metabolism over 90 Sequential Cultures on Wheat-Based Thin Stillage. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:4717-4729. [PMID: 32138511 DOI: 10.1021/acs.jafc.9b07414] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Wheat-based thin stillage (W-TS) is a liquid co-product of wheat fermentation for ethanol production, which typically contains substantial amounts of glycerol. Two-stage fermentation, via endemic microorganisms, can be used in processes to convert this compound to more valuable products and simplify the enrichment process through the clarification of the medium and concentration of particles as a protein-rich concentrate. We recultured bacteria 90 times (72 h at 37 °C) on fresh W-TS to determine the stability of the culture and metabolic processes. Next-generation sequencing of W-TS revealed the presence of a predominant Lactobacillus community that rapidly displaced competing microorganisms (e.g., Pediococcus) in subsequent fermentations. These organisms produced bacteriocins (e.g., helveticin J, interpreted through the presence of bacteriocin genes) and acidified the fermentation broth (through the production of succinic acid: 1.7 g/L, lactic acid: 1.8 g/L, and acetic acid: 4.1 g/L). Furthermore, the microbial community produced cobalamin (inferred through sequencing) and converted glycerol (10 g/L reduced to 3.5 g/L after 72 h) to 1,3-propanediol (6.1 g/L after 72 h). Altogether, Lactobacilli were identified as the predominant endemic microorganisms in W-TS after the first 10 cultures. The community was stable and provided a novel approach to increase the value of organic solutes in W-TS.
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Affiliation(s)
- Timothy J Tse
- Department of Plant Sciences, University of Saskatchewan, 51 Campus Drive, Saskatoon, Saskatchewan S7N 5A8, Canada
| | - Jianheng Shen
- Department of Plant Sciences, University of Saskatchewan, 51 Campus Drive, Saskatoon, Saskatchewan S7N 5A8, Canada
| | - Youn Young Shim
- Department of Plant Sciences, University of Saskatchewan, 51 Campus Drive, Saskatoon, Saskatchewan S7N 5A8, Canada
- Prairie Tide Diversified Inc., 102 Melville Street, Saskatoon Saskatchewan S7J 0R1, Canada
- Guangdong Saskatchewan Oilseed Joint Laboratory, Department of Food Science and Engineering, Jinan University, 601 Huangpu Avenue West, Guangzhou, Guangdong 510632, China
- Department of Integrative Biotechnology, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon, Gyeonggi-do 16419, Korea
| | - Martin J T Reaney
- Department of Plant Sciences, University of Saskatchewan, 51 Campus Drive, Saskatoon, Saskatchewan S7N 5A8, Canada
- Prairie Tide Diversified Inc., 102 Melville Street, Saskatoon Saskatchewan S7J 0R1, Canada
- Guangdong Saskatchewan Oilseed Joint Laboratory, Department of Food Science and Engineering, Jinan University, 601 Huangpu Avenue West, Guangzhou, Guangdong 510632, China
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6
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Musatti A, Cavicchioli D, Mapelli C, Bertoni D, Hogenboom JA, Pellegrino L, Rollini M. From Cheese Whey Permeate to Sakacin A: A Circular Economy Approach for the Food-Grade Biotechnological Production of an Anti- Listeria Bacteriocin. Biomolecules 2020; 10:biom10040597. [PMID: 32290606 PMCID: PMC7226247 DOI: 10.3390/biom10040597] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 04/07/2020] [Accepted: 04/10/2020] [Indexed: 12/13/2022] Open
Abstract
Cheese Whey Permeate (CWP) is the by-product of whey ultrafiltration for protein recovery. It is highly perishable with substantial disposal costs and has serious environmental impact. The aim of the present study was to develop a novel and cheap CWP-based culture medium for Lactobacillus sakei to produce the food-grade sakacin A, a bacteriocin exhibiting a specific antilisterial activity. Growth conditions, nutrient supplementation and bacteriocin yield were optimized through an experimental design in which the standard medium de Man, Rogosa and Sharpe (MRS) was taken as benchmark. The most convenient formulation was liquid CWP supplemented with meat extract (4 g/L) and yeast extract (8 g/L). Although, arginine (0.5 g/L) among free amino acids was depleted in all conditions, its supplementation did not increase process yield. The results demonstrate the feasibility of producing sakacin A from CWP. Cost of the novel medium was 1.53 €/L and that of obtaining sakacin A 5.67 €/106 AU, with a significant 70% reduction compared to the corresponding costs with MRS (5.40 €/L, 18.00 €/106 AU). Taking into account that the limited use of bacteriocins for food application is mainly due to the high production cost, the obtained reduction may contribute to widening the range of applications of sakacin A as antilisterial agent.
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Affiliation(s)
- Alida Musatti
- DeFENS, Department of Food, Environmental and Nutritional Sciences (DeFENS), Università degli Studi di Milano, Via Mangiagalli 25, 20133 Milano, Italy; (C.M.); (J.A.H.); (L.P.); (M.R.)
- Correspondence: ; Tel.: +39-025-031-9150
| | - Daniele Cavicchioli
- ESP, Department of Environmental Science and Policy, Università degli Studi di Milano, Via G. Celoria 2, 20133 Milano, Italy; (D.C.); (D.B.)
| | - Chiara Mapelli
- DeFENS, Department of Food, Environmental and Nutritional Sciences (DeFENS), Università degli Studi di Milano, Via Mangiagalli 25, 20133 Milano, Italy; (C.M.); (J.A.H.); (L.P.); (M.R.)
| | - Danilo Bertoni
- ESP, Department of Environmental Science and Policy, Università degli Studi di Milano, Via G. Celoria 2, 20133 Milano, Italy; (D.C.); (D.B.)
| | - Johannes A. Hogenboom
- DeFENS, Department of Food, Environmental and Nutritional Sciences (DeFENS), Università degli Studi di Milano, Via Mangiagalli 25, 20133 Milano, Italy; (C.M.); (J.A.H.); (L.P.); (M.R.)
| | - Luisa Pellegrino
- DeFENS, Department of Food, Environmental and Nutritional Sciences (DeFENS), Università degli Studi di Milano, Via Mangiagalli 25, 20133 Milano, Italy; (C.M.); (J.A.H.); (L.P.); (M.R.)
| | - Manuela Rollini
- DeFENS, Department of Food, Environmental and Nutritional Sciences (DeFENS), Università degli Studi di Milano, Via Mangiagalli 25, 20133 Milano, Italy; (C.M.); (J.A.H.); (L.P.); (M.R.)
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Sushida H, Ishibashi N, Zendo T, Wilaipun P, Leelawatcharamas V, Nakayama J, Sonomoto K. Evaluation of leader peptides that affect the secretory ability of a multiple bacteriocin transporter, EnkT. J Biosci Bioeng 2018; 126:23-29. [DOI: 10.1016/j.jbiosc.2018.01.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 01/11/2018] [Accepted: 01/19/2018] [Indexed: 11/24/2022]
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8
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Daba G, Ishibashi N, Zendo T, Sonomoto K. Functional analysis of the biosynthetic gene cluster required for immunity and secretion of a novelLactococcus-specific bacteriocin, lactococcin Z. J Appl Microbiol 2017; 123:1124-1132. [DOI: 10.1111/jam.13564] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 07/18/2017] [Accepted: 08/08/2017] [Indexed: 01/11/2023]
Affiliation(s)
- G.M. Daba
- Department of Bioscience and Biotechnology; Faculty of Agriculture; Graduate School; Kyushu University; Fukuoka Japan
| | - N. Ishibashi
- Department of Bioscience and Biotechnology; Faculty of Agriculture; Graduate School; Kyushu University; Fukuoka Japan
| | - T. Zendo
- Department of Bioscience and Biotechnology; Faculty of Agriculture; Graduate School; Kyushu University; Fukuoka Japan
| | - K. Sonomoto
- Department of Bioscience and Biotechnology; Faculty of Agriculture; Graduate School; Kyushu University; Fukuoka Japan
- Department of Functional Metabolic Design; Bio-Architecture Center; Kyushu University; Fukuoka Japan
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9
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Monedero V, Revilla-Guarinos A, Zúñiga M. Physiological Role of Two-Component Signal Transduction Systems in Food-Associated Lactic Acid Bacteria. ADVANCES IN APPLIED MICROBIOLOGY 2017; 99:1-51. [PMID: 28438266 DOI: 10.1016/bs.aambs.2016.12.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Two-component systems (TCSs) are widespread signal transduction pathways mainly found in bacteria where they play a major role in adaptation to changing environmental conditions. TCSs generally consist of sensor histidine kinases that autophosphorylate in response to a specific stimulus and subsequently transfer the phosphate group to their cognate response regulators thus modulating their activity, usually as transcriptional regulators. In this review we present the current knowledge on the physiological role of TCSs in species of the families Lactobacillaceae and Leuconostocaceae of the group of lactic acid bacteria (LAB). LAB are microorganisms of great relevance for health and food production as the group spans from starter organisms to pathogens. Whereas the role of TCSs in pathogenic LAB (most of them belonging to the family Streptococcaceae) has focused the attention, the roles of TCSs in commensal LAB, such as most species of Lactobacillaceae and Leuconostocaceae, have been somewhat neglected. However, evidence available indicates that TCSs are key players in the regulation of the physiology of these bacteria. The first studies in food-associated LAB showed the involvement of some TCSs in quorum sensing and production of bacteriocins, but subsequent studies have shown that TCSs participate in other physiological processes, such as stress response, regulation of nitrogen metabolism, regulation of malate metabolism, and resistance to antimicrobial peptides, among others.
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Affiliation(s)
- Vicente Monedero
- Instituto de Agroquímica y Tecnología de Alimentos (CSIC), Paterna, Spain
| | | | - Manuel Zúñiga
- Instituto de Agroquímica y Tecnología de Alimentos (CSIC), Paterna, Spain
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10
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Comparative genomic analysis of bacteriocin-producing Weissella cibaria 110. Appl Microbiol Biotechnol 2017; 101:1227-1237. [PMID: 28058448 DOI: 10.1007/s00253-016-8073-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 12/10/2016] [Accepted: 12/17/2016] [Indexed: 10/20/2022]
Abstract
Weissella cibaria 110 was isolated from plaa-som, a Thai fermented fish product, and known to produce the weissellicin 110 bacteriocin. We carried out comprehensive comparative genomic analysis of W. cibaria 110 with four other non-bacteriocin-producing W. cibaria strains and identified potential antibiotic-resistant genes. We further identified a type III restriction-modification system, a TA system, and a bacteriocin gene cluster that are unique in W. cibaria 110. Genes related to bacteriocin biosynthesis are organized in clusters and are encoded with minimum genetic machinery consisting of structural cognate immunity genes, including ABC transporter and immunity protein. Finally, we predicted W. cibaria 110 to produce a class IId bacteriocin, weissellicin 110, which is 31 amino acids in length and contains a 21-amino-acid N-terminal leader peptide. This is the first bacteriocin-producing sequencing genome in W. cibaria, and we describe the difference between the bacteriocin-producing and non bacteriocin-producing strains from genome point of view.
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11
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From by-product to valuable components: Efficient enzymatic conversion of lactose in whey using β-galactosidase from Streptococcus thermophilus. Biochem Eng J 2016; 116:45-53. [PMID: 27885320 PMCID: PMC5117255 DOI: 10.1016/j.bej.2016.04.003] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
β-Galactosidase from Streptococcus thermophilus was overexpressed in a food-grade organism, Lactobacillus plantarum WCFS1. Laboratory cultivations yielded 11,000 U of β-galactosidase activity per liter of culture corresponding to approximately 170 mg of enzyme. Crude cell-free enzyme extracts obtained by cell disruption and subsequent removal of cell debris showed high stability and were used for conversion of lactose in whey permeate. The enzyme showed high transgalactosylation activity. When using an initial concentration of whey permeate corresponding to 205 g L-1 lactose, the maximum yield of galacto-oligosaccharides (GOS) obtained at 50°C reached approximately 50% of total sugar at 90% lactose conversion, meaning that efficient valorization of the whey lactose was obtained. GOS are of great interest for both human and animal nutrition; thus, efficient conversion of lactose in whey into GOS using an enzymatic approach will not only decrease the environmental impact of whey disposal, but also create additional value.
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12
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Ekblad B, Kyriakou PK, Oppegård C, Nissen-Meyer J, Kaznessis YN, Kristiansen PE. Structure-Function Analysis of the Two-Peptide Bacteriocin Plantaricin EF. Biochemistry 2016; 55:5106-16. [PMID: 27538436 PMCID: PMC5026404 DOI: 10.1021/acs.biochem.6b00588] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 08/16/2016] [Indexed: 11/30/2022]
Abstract
Plantaricin EF is a two-peptide bacteriocin that depends on the complementary action of two different peptides (PlnE and PlnF) to function. The structures of the individual peptides have previously been analyzed by nuclear magnetic resonance spectroscopy ( Fimland, N. et al. ( 2008 ) , Biochim. Biophys. Acta 1784 , 1711 - 1719 ), but the bacteriocin structure and how the two peptides interact have not been determined. All two-peptide bacteriocins identified so far contain GxxxG motifs. These motifs, together with GxxxG-like motifs, are known to mediate helix-helix interactions in membrane proteins. We have mutated all GxxxG and GxxxG-like motifs in PlnE and PlnF in order to determine if any of these motifs are important for antimicrobial activity and thus possibly for interactions between PlnE and PlnF. Moreover, the aromatic amino acids Tyr and Trp in PlnE and PlnF were substituted, and four fusion polypeptides were constructed in order to investigate the relative orientation of PlnE and PlnF in target cell membranes. The results obtained with the fusion polypeptides indicate that PlnE and PlnF interact in an antiparallel manner and that the C-terminus of PlnE and N-terminus of PlnF are on the outer part of target cell membranes and the N-terminus of PlnE and C-terminus of PlnF are on the inner part. The preference for an aromatic residue at position 6 in PlnE suggests a positioning of this residue in or near the membrane interface on the cells inside. Mutations in the GxxxG motifs indicate that the G5xxxG9 motif in PlnE and the S26xxxG30 motif in PlnF are involved in helix-helix interactions. Atomistic molecular dynamics simulation of a structural model consistent with the results confirmed the stability of the structure and its orientation in membranes. The simulation approved the anticipated interactions and revealed additional interactions that further increase the stability of the proposed structure.
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Affiliation(s)
- Bie Ekblad
- Department
of Biosciences, University of Oslo, P.O. Box 1066, Blindern, 0316 Oslo, Norway
| | - Panagiota K. Kyriakou
- Department
of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Camilla Oppegård
- Department
of Biosciences, University of Oslo, P.O. Box 1066, Blindern, 0316 Oslo, Norway
| | - Jon Nissen-Meyer
- Department
of Biosciences, University of Oslo, P.O. Box 1066, Blindern, 0316 Oslo, Norway
| | - Yiannis N. Kaznessis
- Department
of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Per Eugen Kristiansen
- Department
of Biosciences, University of Oslo, P.O. Box 1066, Blindern, 0316 Oslo, Norway
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13
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Cintas LM, Casaus MP, Herranz C, Nes IF, Hernández PE. Review: Bacteriocins of Lactic Acid Bacteria. FOOD SCI TECHNOL INT 2016. [DOI: 10.1106/r8de-p6hu-clxp-5ryt] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
During the last few years, a large number of new bacteriocins produced by lactic acid bacteria (LAB) have been identified and characterized. LAB-bacteriocins comprise a heterogeneous group of physicochemically diverse ribosomally-synthesized peptides or proteins showing a narrow or broad antimicrobial activity spectrum against Gram-positive bacteria. Bacteriocins are classified into separate groups such as the lantibiotics (Class I); the small (<10 kDa) heat-stable postranslationally unmodified non-lantibiotics (Class II), further subdivided in the pediocin-like and anti Listeria bacteriocins (subclass IIa), the two-peptide bacteriocins (subclass IIb), and the sec-dependent bacteriocins (subclass IIc); and the large (>30 kDa) heat-labile non-lantibiotics (Class III). Most bacteriocins characterized to date belong to Class II and are synthesized as precursor peptides (preprobacteriocins) containing an N-terminal double-glycine leader peptide, which is cleaved off concomitantly with externalization of biologically active bacteriocins by a dedicated ABC-transporter and its accessory protein. However, the recently identified sec-dependent bacteriocins contain an N-terminal signal peptide that directs bacteriocin secretion through the general secretory pathway (GSP). Most LAB-bacteriocins act on sensitive cells by destabilization and permeabilization of the cytoplasmic membrane through the formation of transitory poration complexes or ionic channels that cause the reduction or dissipation of the proton motive force (PMF). Bacteriocin producing LAB strains protect themselves against the toxicity of their own bacteriocins by the expression of a specific immunity protein which is generally encoded in the bacteriocin operon. Bacteriocin production in LAB is frequently regulated by a three-component signal transduction system consisting of an induction factor (IF), and histidine protein kinase (HPK) and a response regulator (RR). This paper presents an updated review on the general knowledge about physicochemical properties, molecular mode of action, biosynthesis, regulation and genetics of LAB-bacteriocins.
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Affiliation(s)
- L. M. Cintas
- Departamento de Nutrición y Bromatología III (Higiene y Tecnología de los Alimentos), Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain
| | - M. P. Casaus
- Carrefour, Departamento de Marcas Propias, Área de Calidad, Campezo 16, 28022 Madrid
| | - C. Herranz
- Departamento de Nutrición y Bromatología III (Higiene y Tecnología de los Alimentos), Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain
| | - I. F. Nes
- Laboratory of Microbial Gene Technology, Department of Chemistry and Biotechnology, Agricultural University of Norway, P.O. Box 5051, N-1432 Ås, Norway
| | - P. E. Hernández
- Departamento de Nutrición y Bromatología III (Higiene y Tecnología de los Alimentos), Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain
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Aymerich M, Hugas M, Monfort J. Review : Bacteriocinogenic lactic acid bacteria associated with meat products / Revisión: Bacterias lácticas productoras de bacteriocinas asociadas a productos cárnicos. FOOD SCI TECHNOL INT 2016. [DOI: 10.1177/108201329800400301] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Meat consumption is of great economical importance. Several lactic acid bacteria associated with meat products are important natural bacteriocin producers. Bacteriocins are proteinaceous antag onistic substances considered to be important in the control of spoilage and pathogenic microor ganisms. This review aims to present the current state of the art in terms of bacteriocinogenic lactic acid bacteria associated with fresh and fermented meat products, describe the biochemical and genetic characteristics of their bacteriocins and the potential use of bacteriocins production of meat products.
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Affiliation(s)
- M.T. Aymerich
- Meat Technology Center-IRTA. Granja Camps i Armet. 17121 Monells. Girona, Spain
| | - M. Hugas
- Meat Technology Center-IRTA. Granja Camps i Armet. 17121 Monells. Girona, Spain
| | - J.M. Monfort
- Meat Technology Center-IRTA. Granja Camps i Armet. 17121 Monells. Girona, Spain
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Landete JM. A review of food-grade vectors in lactic acid bacteria: from the laboratory to their application. Crit Rev Biotechnol 2016; 37:296-308. [PMID: 26918754 DOI: 10.3109/07388551.2016.1144044] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Lactic acid bacteria (LAB) have a long history of use in fermented foods and as probiotics. Genetic manipulation of these microorganisms has great potential for new applications in food safety, as well as in the development of improved food products and in health. While genetic engineering of LAB could have a major positive impact on the food and pharmaceutical industries, progress could be prevented by legal issues related to the controversy surrounding this technology. The safe use of genetically modified LAB requires the development of food-grade cloning systems containing only the DNA from homologous hosts or generally considered as safe organisms, and not dependent antibiotic markers. The rationale for the development of cloning vectors derived from cryptic LAB plasmids is the need for new genetic engineering tools, therefore a vision from cryptic plasmids to applications in food-grade vectors for LAB plasmids is shown in this review. Replicative and integrative vectors for the construction of food-grade vectors, and the relationship between resistance mechanism and expression systems, will be treated in depth in this paper. Finally, we will discuss the limited use of these vectors, and the problems arising from their use.
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Affiliation(s)
- José Maria Landete
- a Departamento De Tecnología De Alimentos , Instituto Nacional De Investigación Y Tecnología Agraria Y Alimentaria (INIA) , Madrid , Spain
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Heterologous Processing and Export of the Bacteriocins Pediocin PA-1 and Lactococcin A in Lactococcus Lactis: A Study with Leader Exchange. Probiotics Antimicrob Proteins 2016; 2:66-76. [PMID: 26781115 DOI: 10.1007/s12602-009-9023-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The bacteriocins pediocin PA-1 and lactococcin A are synthesized as precursors carrying N-terminal extensions with a conserved cleavage site preceded by two glycine residues in positions -2 and -1. Each bacteriocin is translocated through the cytoplasmic membrane by an integral membrane protein of the ABC cassette superfamily which, in the case of pediocin PA-1, has been shown to possess peptidase activity responsible for proteolytic cleavage of the pre-bacteriocin. In each case, another integral membrane protein is essential for bacteriocin production. In this study, a two-step PCR approach was used to permutate the leaders of pediocin PA-1 and lactococcin A. Wild-type and chimeric pre-bacteriocins were assayed for maturation by the processing/export machinery of pediocin PA-1 and lactococcin A. The results show that pediocin PA-1 can be efficiently exported by the lactococcin machinery whether it carries the lactococcin or the pediocin leader. It can also compete with wild-type lactococcin A for the lactococcin machinery. Pediocin PA-1 carrying the lactococcin A leader or lactococcin A carrying that of pediocin PA-1 was poorly secreted when complemented with the pediocin PA-1 machinery, showing that the pediocin machinery is more specific for its bacteriocin substrate. Wild-type pre-pediocin and chimeric pre-pediocin were shown to be processed by the lactococcin machinery at or near the double-glycine cleavage site. These results show the potential of the lactococcin LcnC/LcnD machinery as a maturation system for peptides carrying double-glycine-type amino-terminal leaders.
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Ishibashi N, Shigeri Y, Sonomoto K, Zendo T, Koga S. Molecular characterization of the genes involved in the secretion and immunity of lactococcin Q, a two-peptide bacteriocin produced by Lactococcus lactis QU 4. Microbiology (Reading) 2015; 161:2069-78. [DOI: 10.1099/mic.0.000157] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Tai HF, Foo HL, Abdul Rahim R, Loh TC, Abdullah MP, Yoshinobu K. Molecular characterisation of new organisation of plnEF and plw loci of bacteriocin genes harbour concomitantly in Lactobacillus plantarum I-UL4. Microb Cell Fact 2015; 14:89. [PMID: 26077560 PMCID: PMC4467070 DOI: 10.1186/s12934-015-0280-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 06/02/2015] [Indexed: 12/05/2022] Open
Abstract
Background Bacteriocin-producing Lactic acid bacteria (LAB) have vast applications in human and animal health, as well as in food industry. The structural, immunity, regulatory, export and modification genes are required for effective bacteriocin biosynthesis. Variations in gene sequence, composition and organisation will affect the antimicrobial spectrum of bacteriocin greatly. Lactobacillus plantarum I-UL4 is a novel multiple bacteriocin producer that harbours both plw and plnEF structural genes simultaneous which has not been reported elsewhere. Therefore, molecular characterisation of bacteriocin genes that harboured in L. plantarum I-UL4 was conducted in this study. Results and discussion Under optimised conditions, 8 genes (brnQ1, napA1, plnL, plnD, plnEF, plnI, plnG and plnH) of plnEF locus and 2 genes (plw and plwG) of plw locus were amplified successfully from genomic DNA extracted from L. plantarum I-UL4 using specific primers designed from 24 pln genes selected randomly from reported plw, plS, pln423 and plnEF loci. DNA sequence analysis of the flanking region of the amplified genes revealed the presence of two pln loci, UL4-plw and UL4-plnEF loci, which were chromosomally encoded as shown by Southern hybridisation. UL4-plw locus that contained three ORFs were arranged in one operon and possessed remarkable amino acid sequence of LMG2379-plw locus, suggesting it was highly conserved. Interestingly, the UL4-plnEF locus appeared to be a composite pln locus of JDM1-plnEF and J51-plnEF locus in terms of genetic composition and organisation, whereby twenty complete and one partial open reading frames (ORFs) were aligned and organised successfully into five operons. Furthermore, a mutation was detected in plnF structural gene which has contributed to a longer bacteriocin peptide. Conclusions Plantaricin EF and plantaricin W encoded by plnEF and plnW loci are classified as class I bacteriocin and class II bacteriocin molecules respectively. The concurrent presence of two pln loci encoding bacteriocins from two different classes has contributed greatly to the broad inhibitory spectrum of L. plantarum I-UL4. The new genetic composition and organisation of plnEF locus and concurrent presence of plnEF and plnW loci indicated that L. plantarum I-UL4 is a novel multiple bacteriocin producer that possesses vast potentials in various industries.
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Affiliation(s)
- Hui Fong Tai
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
| | - Hooi Ling Foo
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia. .,Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
| | - Raha Abdul Rahim
- Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia. .,Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
| | - Teck Chewn Loh
- Department of Animal Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia. .,Institute of Tropical Agriculture, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
| | - Mohd Puad Abdullah
- Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia. .,Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia. .,Institute of Tropical Agriculture, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
| | - Kimura Yoshinobu
- Department of Biofunctional Chemistry, Graduate School of Environmental and Life Sciemce, Okayama University, Okayama, Japan.
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Oppegård C, Fimland G, Anonsen JH, Nissen-Meyer J. The Pediocin PA-1 Accessory Protein Ensures Correct Disulfide Bond Formation in the Antimicrobial Peptide Pediocin PA-1. Biochemistry 2015; 54:2967-74. [PMID: 25961806 DOI: 10.1021/acs.biochem.5b00164] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Peptides, in contrast to proteins, are generally not large enough to form stable and well-defined three-dimensional structures. However, peptides are still able to form correct disulfide bonds. Using pediocin-like bacteriocins, we have examined how this may be achieved. Some pediocin-like bacteriocins, such as pediocin PA-1 and sakacin P[N24C+44C], have four cysteines. There are three possible ways by which the four cysteines may combine to form two disulfide bonds, and the three variants are expected to be produced in approximately equal amounts if their formation is random. Pediocin PA-1 and sakacin P[N24C+44C] with correct disulfide bonds were the main products when they were secreted by the pediocin PA-1 ABC transporter and accessory protein, but when they were secreted by the corresponding secretion machinery for sakacin A, a pediocin-like bacteriocin with one disulfide bond (two cysteines), peptides with all three possible disulfide bonds were produced in approximately equal amounts. All five cysteines in the pediocin PA-1 ABC transporter and the two cysteines (that form a CxxC motif) in the accessory protein were individually replaced with serines to examine their involvement in disulfide bond formation in pediocin PA-1. The Cys86Ser mutation in the accessory protein caused a 2-fold decrease in the amount of pediocin PA-1 with correct disulfide bonds, while the Cys83Ser mutation nearly abolished the production of pediocin PA-1 and resulted in the production of all three disufide bond variants in equal amounts. The Cys19Ser mutation in the ABC transporter completely abolished secretion of pediocin PA-1, suggesting that Cys19 is in the proteolytic active site and involved in cleaving the prebacteriocin. Replacing the other four cysteines in the ABC transporter with serines caused a slight reduction in the overall amount of secreted pediocin PA-1, but the relative amount with the correct disulfide bonds remained large. These results indicate that the pediocin PA-1 accessory protein has a chaperone-like activity in that it ensures the formation of the correct disulfide bond in pediocin PA-1.
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Affiliation(s)
- Camilla Oppegård
- †Department of Biosciences, Section for Biochemistry and Molecular Biology, University of Oslo, P.O. Box 1066, Blindern, 0316 Oslo, Norway
| | - Gunnar Fimland
- ‡Xellia Pharmaceuticals AS, P.O. Box 158, Skøyen, 0212 Oslo, Norway
| | - Jan Haug Anonsen
- †Department of Biosciences, Section for Biochemistry and Molecular Biology, University of Oslo, P.O. Box 1066, Blindern, 0316 Oslo, Norway
| | - Jon Nissen-Meyer
- †Department of Biosciences, Section for Biochemistry and Molecular Biology, University of Oslo, P.O. Box 1066, Blindern, 0316 Oslo, Norway
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Nguyen TT, Nguyen HM, Geiger B, Mathiesen G, Eijsink VGH, Peterbauer CK, Haltrich D, Nguyen TH. Heterologous expression of a recombinant lactobacillal β-galactosidase in Lactobacillus plantarum: effect of different parameters on the sakacin P-based expression system. Microb Cell Fact 2015; 14:30. [PMID: 25880197 PMCID: PMC4358714 DOI: 10.1186/s12934-015-0214-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 02/20/2015] [Indexed: 01/01/2023] Open
Abstract
Background Two overlapping genes lacL and lacM (lacLM) encoding for heterodimeric β-galactosidase from Lactobacillus reuteri were previously cloned and over-expressed in the food-grade host strain Lactobacillus plantarum WCFS1, using the inducible lactobacillal pSIP expression system. In this study, we analyzed different factors that affect the production of recombinant L. reuteri β-galactosidase. Results Various factors related to the cultivation, i.e. culture pH, growth temperature, glucose concentration, as well as the induction conditions, including cell concentration at induction point and inducer concentration, were tested. Under optimal fermentation conditions, the maximum β-galactosidase levels obtained were 130 U/mg protein and 35–40 U/ml of fermentation broth corresponding to the formation of approximately 200 mg of recombinant protein per litre of fermentation medium. As calculated from the specific activity of the purified enzyme (190 U/mg), β-galactosidase yield amounted to roughly 70% of the total soluble intracellular protein of the host organism. It was observed that pH and substrate (glucose) concentration are the most prominent factors affecting the production of recombinant β-galactosidase. Conclusions The over-expression of recombinant L. reuteri β-galactosidase in a food-grade host strain was optimized, which is of interest for applications of this enzyme in the food industry. The results provide more detailed insight into these lactobacillal expression systems and confirm the potential of the pSIP system for efficient, tightly controlled expression of enzymes and proteins in lactobacilli.
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Affiliation(s)
- Tien-Thanh Nguyen
- Food Biotechnology Laboratory, Department of Food Science and Technology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria. .,School of Biotechnology and Food Technology, Hanoi University of Science and Technology, 1 Dai Co Viet Street, Hanoi, Vietnam.
| | - Hoang-Minh Nguyen
- Food Biotechnology Laboratory, Department of Food Science and Technology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria. .,Department of Biotechnology, Danang University of Technology, Nguyen Luong Bang 54, Danang, Vietnam.
| | - Barbara Geiger
- Food Biotechnology Laboratory, Department of Food Science and Technology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria.
| | - Geir Mathiesen
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, , N-1432, Ǻs, Norway.
| | - Vincent G H Eijsink
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, , N-1432, Ǻs, Norway.
| | - Clemens K Peterbauer
- Food Biotechnology Laboratory, Department of Food Science and Technology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria.
| | - Dietmar Haltrich
- Food Biotechnology Laboratory, Department of Food Science and Technology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria.
| | - Thu-Ha Nguyen
- Food Biotechnology Laboratory, Department of Food Science and Technology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria.
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Gene cluster responsible for secretion of and immunity to multiple bacteriocins, the NKR-5-3 enterocins. Appl Environ Microbiol 2014; 80:6647-55. [PMID: 25149515 DOI: 10.1128/aem.02312-14] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Enterococcus faecium NKR-5-3, isolated from Thai fermented fish, is characterized by the unique ability to produce five bacteriocins, namely, enterocins NKR-5-3A, -B, -C, -D, and -Z (Ent53A, Ent53B, Ent53C, Ent53D, and Ent53Z). Genetic analysis with a genome library revealed that the bacteriocin structural genes (enkA [ent53A], enkC [ent53C], enkD [ent53D], and enkZ [ent53Z]) that encode these peptides (except for Ent53B) are located in close proximity to each other. This NKR-5-3ACDZ (Ent53ACDZ) enterocin gene cluster (approximately 13 kb long) includes certain bacteriocin biosynthetic genes such as an ABC transporter gene (enkT), two immunity genes (enkIaz and enkIc), a response regulator (enkR), and a histidine protein kinase (enkK). Heterologous-expression studies of enkT and ΔenkT mutant strains showed that enkT is responsible for the secretion of Ent53A, Ent53C, Ent53D, and Ent53Z, suggesting that EnkT is a wide-range ABC transporter that contributes to the effective production of these bacteriocins. In addition, EnkIaz and EnkIc were found to confer self-immunity to the respective bacteriocins. Furthermore, bacteriocin induction assays performed with the ΔenkRK mutant strain showed that EnkR and EnkK are regulatory proteins responsible for bacteriocin production and that, together with Ent53D, they constitute a three-component regulatory system. Thus, the Ent53ACDZ gene cluster is essential for the biosynthesis and regulation of NKR-5-3 enterocins, and this is, to our knowledge, the first report that demonstrates the secretion of multiple bacteriocins by an ABC transporter.
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Miller P, McMullen LM. Mechanism for temperature-dependent production of piscicolin 126. MICROBIOLOGY-SGM 2014; 160:1670-1678. [PMID: 24858287 DOI: 10.1099/mic.0.078030-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Piscicolin 126 is a class 2a bacteriocin produced by Carnobacterium maltaromaticum strains UAL26 and JG126. Whilst strain UAL26 shows temperature-dependent piscicolin 126 production, strain JG126 produces bacteriocin at any growth temperature. Several clones containing combinations of the ATP-binding cassette transporter (pisT) and transporter accessory (pisE) genes from JG126 and UAL26 were created and tested for bacteriocin production. Bacteriocin production at 25 °C was observed only for a clone containing both pisT and pisE from JG126 (U-T(J)E(J)) and a clone containing pisT from UAL26 and pisE from JG126 (U-BamT(U)E(J)). Therefore, the deletion of a single CG base pair located on pisE of UAL26 that results in a frameshift and truncation of PisE causes the temperature-dependent piscicolin 126 production. Bacteriocin production of UAL26 was induced at 25 °C by the addition of supernatant containing the autoinducer peptide (AIP); however, the antimicrobial activity was lost after two subsequent overnight cultivations due to the presumed lack of the AIP. Changes in membrane fluidity due to changes in temperature or the presence of 2-phenylethanol (PHE) affected bacteriocin production of UAL26, but not of clones U-T(J)E(J) or U-BamT(U)E(J). Similarly, increased membrane fluidity due to PHE addition reduced production of sakacin A in Lactobacillus sakei Lb706 and Lactobacillus curvatus LTH 1174. The mechanism involved in the temperature-dependent piscicolin 126 production was described. Due to the conformational change in PisE at 25 °C, the transport machinery was not able to translocate AIP. To the best of our knowledge, this is the first report that links membrane fluidity with the regulation of bacteriocin production.
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Affiliation(s)
- Petr Miller
- Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada
| | - Lynn M McMullen
- Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada
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Dimov S, Ivanova P, Harizanova N. Genetics of Bacteriocins Biosynthesis by Lactic Acid Bacteria. BIOTECHNOL BIOTEC EQ 2014. [DOI: 10.1080/13102818.2005.10817270] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Barbosa MS, Todorov SD, Belguesmia Y, Choiset Y, Rabesona H, Ivanova IV, Chobert JM, Haertlé T, Franco BDGM. Purification and characterization of the bacteriocin produced by Lactobacillus sakei MBSa1 isolated from Brazilian salami. J Appl Microbiol 2014; 116:1195-208. [PMID: 24506656 DOI: 10.1111/jam.12438] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 11/19/2013] [Accepted: 01/06/2014] [Indexed: 11/29/2022]
Abstract
AIMS The study aimed at determining the biochemical characteristics of the bacteriocin produced by Lactobacillus sakei MBSa1, isolated from salami, correlating the results with the genetic features of the producer strain. METHODS AND RESULTS Identification of strain MBSa1 was performed by 16S rDNA sequencing. The bacteriocin was tested for spectrum of activity, heat and pH stability, mechanism of action, molecular mass and amino acid sequence when purified by cation-exchange and reversed-phase HPLC. Genomic DNA was tested for bacteriocin genes commonly present in Lact. sakei. Bacteriocin MBSa1 was heat-stable, unaffected by pH 2·0 to 6·0 and active against all tested Listeria monocytogenes strains. Maximal production of bacteriocin MBSa1 (1600 AU ml(-1)) in MRS broth occurred after 20 h at 25°C. The molecular mass of produced bacteriocin was 4303·3 Da, and the molecule contained the SIIGGMISGWAASGLAG sequence, also present in sakacin A. The strain contained the sakacin A and curvacin A genes but was negative for other tested sakacin genes (sakacins T-α, T-β, X, P, G and Q). CONCLUSIONS In the studied conditions, Lact. sakei MBSa1 produced sakacin A, a class II bacteriocin, with anti-Listeria activity. SIGNIFICANCE AND IMPACT OF THE STUDY The study covers the purification and characterization of the bacteriocin produced by a lactic acid bacteria isolated from salami (Lact. sakei MBSa1), linking genetic and expression information. Its heat-resistance, pH stability in acid conditions (pH 2·0-6·0) and activity against L. monocytogenes food isolates bring up a potential technological application to improve food safety.
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Affiliation(s)
- M S Barbosa
- Departamento de Alimentos e Nutrição Experimental, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, Brazil
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Jiménez JJ, Borrero J, Diep DB, Gútiez L, Nes IF, Herranz C, Cintas LM, Hernández PE. Cloning, production, and functional expression of the bacteriocin sakacin A (SakA) and two SakA-derived chimeras in lactic acid bacteria (LAB) and the yeasts Pichia pastoris and Kluyveromyces lactis. J Ind Microbiol Biotechnol 2013; 40:977-93. [PMID: 23794087 DOI: 10.1007/s10295-013-1302-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Accepted: 05/30/2013] [Indexed: 11/25/2022]
Abstract
Mature sakacin A (SakA, encoded by sapA) and its cognate immunity protein (SakI, encoded by sapiA), and two SakA-derived chimeras mimicking the N-terminal end of mature enterocin P (EntP/SakA) and mature enterocin A (EntA/SakA) together with SakI, were fused to different signal peptides (SP) and cloned into the protein expression vectors pNZ8048 and pMG36c for evaluation of their production and functional expression by different lactic acid bacteria. The amount, antimicrobial activity, and specific antimicrobial activity of SakA and its chimeras produced by Lactococcus lactis subsp. cremoris NZ9000 depended on the SP and the expression vector. Only L. lactis NZ9000 (pNUPS), producing EntP/SakA, showed higher bacteriocin production and antimicrobial activity than the natural SakA-producer Lactobacillus sakei Lb706. The lower antimicrobial activity of the SakA-producer L. lactis NZ9000 (pNUS) and that of the EntA/SakA-producer L. lactis NZ9000 (pNUAS) could be ascribed to secretion of truncated bacteriocins. On the other hand, of the Lb. sakei Lb706 cultures transformed with the pMG36c-derived vectors only Lb. sakei Lb706 (pGUS) overproducing SakA showed a higher antimicrobial activity than Lb. sakei Lb706. Finally, cloning of SakA and EntP/SakA into pPICZαA and pKLAC2 permitted the production of SakA and EntP/SakA by recombinant Pichia pastoris X-33 and Kluyveromyces lactis GG799 derivatives although their antimicrobial activity was lower than expected from their production.
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Affiliation(s)
- Juan J Jiménez
- Departamento de Nutrición, Bromatología y Tecnología de los Alimentos, Facultad de Veterinaria, Universidad Complutense de Madrid (UCM), Avenida Puerta de Hierro, s/n, 28040, Madrid, Spain
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Cui Y, Zhang C, Wang Y, Shi J, Zhang L, Ding Z, Qu X, Cui H. Class IIa bacteriocins: diversity and new developments. Int J Mol Sci 2012; 13:16668-707. [PMID: 23222636 PMCID: PMC3546714 DOI: 10.3390/ijms131216668] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Revised: 10/10/2012] [Accepted: 11/12/2012] [Indexed: 12/02/2022] Open
Abstract
Class IIa bacteriocins are heat-stable, unmodified peptides with a conserved amino acids sequence YGNGV on their N-terminal domains, and have received much attention due to their generally recognized as safe (GRAS) status, their high biological activity, and their excellent heat stability. They are promising and attractive agents that could function as biopreservatives in the food industry. This review summarizes the new developments in the area of class IIa bacteriocins and aims to provide uptodate information that can be used in designing future research.
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Affiliation(s)
- Yanhua Cui
- School of Food Science and Engineering, Harbin Institute of Technology, Harbin 150090, China; E-Mails: (Y.C.); (C.Z.); (Z.D.)
| | - Chao Zhang
- School of Food Science and Engineering, Harbin Institute of Technology, Harbin 150090, China; E-Mails: (Y.C.); (C.Z.); (Z.D.)
| | - Yunfeng Wang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China; E-Mail:
| | - John Shi
- Guelph Food Research Center, Agriculture and Agri-Food Canada, Guelph, ON N1G5C9, Canada; E-Mail:
| | - Lanwei Zhang
- School of Food Science and Engineering, Harbin Institute of Technology, Harbin 150090, China; E-Mails: (Y.C.); (C.Z.); (Z.D.)
| | - Zhongqing Ding
- School of Food Science and Engineering, Harbin Institute of Technology, Harbin 150090, China; E-Mails: (Y.C.); (C.Z.); (Z.D.)
| | - Xiaojun Qu
- Institute of Microbiology, Heilongjiang Academy of Sciences, Harbin 150010, China; E-Mail:
| | - Hongyu Cui
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China; E-Mail:
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Du L, Somkuti GA, Renye JA. Molecular analysis of the bacteriocin-encoding plasmid pDGL1 from Enterococcus durans and genetic characterization of the durancin GL locus. Microbiology (Reading) 2012; 158:1523-1532. [DOI: 10.1099/mic.0.055624-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Lihui Du
- College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing 210003, PR China
| | - George A. Somkuti
- Eastern Regional Research Center, ARS, US Department of Agriculture Wyndmoor, PA 19038, USA
| | - John A. Renye
- Eastern Regional Research Center, ARS, US Department of Agriculture Wyndmoor, PA 19038, USA
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Yermolenko E, Chernysh A, Kolobov A, Suvorov A. Influence of synthetic peptide inducers on antibacterial activity of enterococci. Benef Microbes 2012; 2:9-13. [PMID: 21840807 DOI: 10.3920/bm2010.0006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Antibacterial activity of probiotic enterococci is often related to the production of bacteriocins. There is a variety of Enterococcus faecium strains which synthesise one or several enterocins including A, B, P, 96, L50AB and others. In this work we have analysed the probiotic strain E. faecium L3 whose genome contained the genes encoding enterocins А, В and a three-component regulatory system. All these genes were found to be expressed in enterococcal strain L3. Antimicrobial activity of the strain tested on the strains of Listeria monocytogenes and Streptococcus agalactiae was pheromone dependent. Chemically synthesised cyclic peptides (analogues and shorter derivates of EntF) with different molecular structures were able to increase the antagonistic activity of the strain E. faecium L3 in contrast to the strain E. faecium SF68, which does nоt have genes encoding enterocins А and В.
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Affiliation(s)
- E Yermolenko
- Department of Molecular Microbiology, Institute of Experimental Medicine, St. Petersburg, Russia
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Nguyen TT, Nguyen TH, Maischberger T, Schmelzer P, Mathiesen G, Eijsink VG, Haltrich D, Peterbauer CK. Quantitative transcript analysis of the inducible expression system pSIP: comparison of the overexpression of Lactobacillus spp. β-galactosidases in Lactobacillus plantarum. Microb Cell Fact 2011; 10:46. [PMID: 21696579 PMCID: PMC3155831 DOI: 10.1186/1475-2859-10-46] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Accepted: 06/22/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Two sets of overlapping genes, lacLMReu and lacLMAci, encoding heterodimeric β-galactosidases from Lactobacillus reuteri and Lactobacillus acidophilus, respectively, have previously been cloned and expressed using the pSIP vector system and Lactobacillus plantarum WCSF1 as host. Despite the high similarity between these lacLM genes and the use of identical cloning and expression strategies, strains harboring lacLMReu produced about twenty-fold more β-galactosidase than strains containing lacLMAci. RESULTS In this study, the plasmid copy numbers (PCN) of expression vectors pEH9R (lacLMReu) and pEH9A (lacLMAci) as well as the transcription levels of both lacLM genes were compared using quantitative PCR methods. Analyses of parallel fermentations of L. plantarum harboring either pEH9R or pEH9A showed that the expression plasmids were present in similar copy numbers. However, transcript levels of lacLM from L. reuteri (pEH9R) were up to 18 times higher than those of lacLM from L. acidophilus (pEH9A). As a control, it was shown that the expression levels of regulatory genes involved in pheromone-induced promoter activation were similar in both strains. CONCLUSION The use of identical expression strategies for highly similar genes led to very different mRNA levels. The data indicate that this difference is primarily caused by translational effects that are likely to affect both mRNA synthesis rates and mRNA stability. These translational effects thus seem to be a dominant determinant for the success of gene expression efforts in lactobacilli.
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Affiliation(s)
- Tien-Thanh Nguyen
- Food Biotechnology Lab, Department of Food Sciences and Technology, University of Natural Resources and Life Sciences Vienna, Austria
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31
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Thoendel M, Kavanaugh JS, Flack CE, Horswill AR. Peptide signaling in the staphylococci. Chem Rev 2010; 111:117-51. [PMID: 21174435 DOI: 10.1021/cr100370n] [Citation(s) in RCA: 285] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Matthew Thoendel
- Department of Microbiology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242, USA
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Zouhir A, Hammami R, Fliss I, Hamida JB. A New Structure-based Classification of Gram-positive Bacteriocins. Protein J 2010; 29:432-9. [DOI: 10.1007/s10930-010-9270-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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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.
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Affiliation(s)
- Julie Shareck
- Department of Food Science and Agricultural Chemistry, McGill University, Ste-Anne-de-Bellevue, Quebec, Canada
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Oppegård C, Rogne P, Kristiansen PE, Nissen-Meyer J. Structure analysis of the two-peptide bacteriocin lactococcin G by introducing d-amino acid residues. Microbiology (Reading) 2010; 156:1883-1889. [DOI: 10.1099/mic.0.038430-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The importance of 3D structuring in the N- and C-terminal ends of the two peptides (39-mer LcnG-α and 35-mer LcnG-β) that constitute the two-peptide bacteriocin lactococcin G was analysed by replacing residues in the end regions with the corresponding d-isomeric residues. When assayed for antibacterial activity in combination with the complementary wild-type peptide, LcnG-α with four d-residues in its C-terminal region and LcnG-β with four d-residues in either its N- or its C-terminal region were relatively active (two- to 20-fold reduction in activity). 3D structuring of the C-terminal region in LcnG-α and the C- and N-terminal regions in LcnG-β is thus not particularly critical for retaining antibacterial activity, indicating that the 3D structure of these regions is not vital for interpeptide interactions or for interactions between the peptides and cellular components. The 3D structure of the N-terminal region in LcnG-α may be more important, as LcnG-α with four N-terminal d-residues was the least active of these four peptides (10- to 100-fold reduction in activity). The results are consistent with a proposed structural model of lactococcin G in which LcnG-α and -β form a transmembrane parallel helix–helix structure involving approximately 20 residues in each peptide, starting near the N terminus of LcnG-α and at about residue 13 in LcnG-β. Upon expressing the lactococcin G immunity protein, sensitive target cells became resistant to all of these d-residue-containing peptides. The end regions of the two lactococcin G peptides are consequently not involved in essential structure-dependent interactions with the immunity protein. The relatively high activity of most of the d-residue-containing peptides suggests that bacteriocins with increased resistance to exopeptidases may be generated by replacing their N- and C-terminal residues with d-residues.
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Affiliation(s)
- Camilla Oppegård
- Department of Molecular Biosciences, University of Oslo, PO Box 1041 Blindern, 0316 Oslo, Norway
| | - Per Rogne
- Department of Molecular Biosciences, University of Oslo, PO Box 1041 Blindern, 0316 Oslo, Norway
| | - Per Eugen Kristiansen
- Department of Molecular Biosciences, University of Oslo, PO Box 1041 Blindern, 0316 Oslo, Norway
| | - Jon Nissen-Meyer
- Department of Molecular Biosciences, University of Oslo, PO Box 1041 Blindern, 0316 Oslo, Norway
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Abstract
The Abi protein family consists of putative membrane-bound metalloproteases. While they are involved in membrane anchoring of proteins in eukaryotes, little is known about their function in prokaryotes. In some known bacteriocin loci, Abi genes have been found downstream of bacteriocin structural genes (e.g., pln locus from Lactobacillus plantarum and sag locus from Streptococcus pyogenes), where they probably are involved in self-immunity. By modifying the profile hidden Markov model used to select Abi proteins in the Pfam protein family database, we show that this family is larger than presently recognized. Using bacteriocin-associated Abi genes as a means to search for novel bacteriocins in sequenced genomes, seven new bacteriocin-like loci were identified in Gram-positive bacteria. One such locus, from Lactobacillus sakei 23K, was selected for further experimental study, and it was confirmed that the bacteriocin-like genes (skkAB) exhibited antimicrobial activity when expressed in a heterologous host and that the associated Abi gene (skkI) conferred immunity against the cognate bacteriocin. Similar investigation of the Abi gene plnI and the Abi-like gene plnL from L. plantarum also confirmed their involvement in immunity to their cognate bacteriocins (PlnEF and PlnJK, respectively). Interestingly, the immunity genes from these three systems conferred a high degree of cross-immunity against each other's bacteriocins, suggesting the recognition of a common receptor. Site-directed mutagenesis demonstrated that the conserved motifs constituting the putative proteolytic active site of the Abi proteins are essential for the immunity function of SkkI, and to our knowledge, this represents a new concept in self-immunity.
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The lactococcin G immunity protein recognizes specific regions in both peptides constituting the two-peptide bacteriocin lactococcin G. Appl Environ Microbiol 2009; 76:1267-73. [PMID: 20038710 DOI: 10.1128/aem.02600-09] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lactococcin G and enterocin 1071 are two homologous two-peptide bacteriocins. Expression vectors containing the gene encoding the putative lactococcin G immunity protein (lagC) or the gene encoding the enterocin 1071 immunity protein (entI) were constructed and introduced into strains sensitive to one or both of the bacteriocins. Strains that were sensitive to lactococcin G became immune to lactococcin G when expressing the putative lactococcin G immunity protein, indicating that the lagC gene in fact encodes a protein involved in lactococcin G immunity. To determine which peptide or parts of the peptide(s) of each bacteriocin that are recognized by the cognate immunity protein, combinations of wild-type peptides and hybrid peptides from the two bacteriocins were assayed against strains expressing either of the two immunity proteins. The lactococcin G immunity protein rendered the enterococcus strain but not the lactococcus strains resistant to enterocin 1071, indicating that the functionality of the immunity protein depends on a cellular component. Moreover, regions important for recognition by the immunity protein were identified in both peptides (Lcn-alpha and Lcn-beta) constituting lactococcin G. These regions include the N-terminal end of Lcn-alpha (residues 1 to 13) and the C-terminal part of Lcn-beta (residues 14 to 24). According to a previously proposed structural model of lactococcin G, these regions will be positioned adjacent to each other in the transmembrane helix-helix structure, and the model thus accommodates the present results.
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The structure of pyogenecin immunity protein, a novel bacteriocin-like immunity protein from Streptococcus pyogenes. BMC STRUCTURAL BIOLOGY 2009; 9:75. [PMID: 20017931 PMCID: PMC2806384 DOI: 10.1186/1472-6807-9-75] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2009] [Accepted: 12/17/2009] [Indexed: 11/10/2022]
Abstract
Background Many Gram-positive lactic acid bacteria (LAB) produce anti-bacterial peptides and small proteins called bacteriocins, which enable them to compete against other bacteria in the environment. These peptides fall structurally into three different classes, I, II, III, with class IIa being pediocin-like single entities and class IIb being two-peptide bacteriocins. Self-protective cognate immunity proteins are usually co-transcribed with these toxins. Several examples of cognates for IIa have already been solved structurally. Streptococcus pyogenes, closely related to LAB, is one of the most common human pathogens, so knowledge of how it competes against other LAB species is likely to prove invaluable. Results We have solved the crystal structure of the gene-product of locus Spy_2152 from S. pyogenes, (PDB:2fu2), and found it to comprise an anti-parallel four-helix bundle that is structurally similar to other bacteriocin immunity proteins. Sequence analyses indicate this protein to be a possible immunity protein protective against class IIa or IIb bacteriocins. However, given that S. pyogenes appears to lack any IIa pediocin-like proteins but does possess class IIb bacteriocins, we suggest this protein confers immunity to IIb-like peptides. Conclusions Combined structural, genomic and proteomic analyses have allowed the identification and in silico characterization of a new putative immunity protein from S. pyogenes, possibly the first structure of an immunity protein protective against potential class IIb two-peptide bacteriocins. We have named the two pairs of putative bacteriocins found in S. pyogenes pyogenecin 1, 2, 3 and 4.
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Molecular and genetic characterization of a novel bacteriocin locus in Enterococcus avium isolates from infants. Appl Environ Microbiol 2009; 76:483-92. [PMID: 19933345 DOI: 10.1128/aem.01597-09] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Enterococci are among the most common human intestinal lactic acid bacteria, and they are known to produce bacteriocins. In this study, fecal enterococci were isolated from infants and screened for bacteriocin production. Bacteriocin-producing Enterococcus avium isolates were obtained, and a new pediocin-like bacteriocin was purified and characterized. This bacteriocin, termed avicin A, was found to be produced by isolates from two healthy infants. It was purified to homogeneity from culture supernatant by ion-exchange and reversed-phase chromatography, and part of its amino acid sequence was obtained. The sequence of a 7-kb DNA fragment of a bacteriocin locus was determined by PCR and DNA sequencing. The bacteriocin locus was organized into four operon-like structures consisting of (i) the structural genes encoding avicin A and its immunity protein, (ii) a divergicin-like bacteriocin (avicin B) gene, (iii) an ABC bacteriocin transporter gene and two regulatory genes (histamine protein kinase- and response regulator-encoding genes), and (iv) induction peptide pheromone- and transport accessory protein-encoding genes. It was shown that the production of avicin A was regulated by the peptide pheromone-inducible regulatory system. Avicin A shows very high levels of similarity to mundticin KS and enterocin CRL35. This bacteriocin showed strong antimicrobial activity against many species of Gram-positive bacteria, including the food-borne pathogen Listeria monocytogenes. The avicin A locus is the first bacteriocin locus identified in E. avium to be characterized at the molecular level.
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Saier MH, Ma CH, Rodgers L, Tamang DG, Yen MR. Protein secretion and membrane insertion systems in bacteria and eukaryotic organelles. ADVANCES IN APPLIED MICROBIOLOGY 2009; 65:141-97. [PMID: 19026865 DOI: 10.1016/s0065-2164(08)00606-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Milton H Saier
- Division of Biological Sciences, University of California at San Diego, La Jolla, California 92093-0116, USA
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Tabasco R, García-Cayuela T, Peláez C, Requena T. Lactobacillus acidophilus La-5 increases lactacin B production when it senses live target bacteria. Int J Food Microbiol 2009; 132:109-16. [PMID: 19411126 DOI: 10.1016/j.ijfoodmicro.2009.04.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Revised: 04/01/2009] [Accepted: 04/05/2009] [Indexed: 10/20/2022]
Abstract
Lactobacillus acidophilus La-5 is a probiotic strain used in dairy products. Production of bacteriocin by L. acidophilus La-5 was achieved when it was grown in co-cultures with the yogurt starter species Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus. However, bacteriocin induction was not observed when heat-killed cells were used as inducers. This study demonstrates that L. acidophilus La-5 produces lactacin B and that the bacteriocin expression is controlled by an auto-induction mechanism involving the secreted peptide IP_1800. The transcript level of the lactacin B gene cluster expression was investigated in co-cultures between L. acidophilus La-5 and S. thermophilus STY-31 and a remarkable increase of the bacteriocin structural gene (lbaB) transcription was observed. However, lbaB was transcribed constitutively in uninduced L. acidophilus La-5 cells, but the levels of the secreted bacteriocin were not enough to be detected by the agar diffusion assay. A new method for bacteriocin detection was formulated based on the monitoring on real time of Lactobacillus sakei subsp. sakei growth in presence of the supernatant and the cell wall extracts of pure and induced L. acidophilus La-5. These results showed that part of lactacin B secreted remains adhered to cell envelope.
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Affiliation(s)
- Raquel Tabasco
- Department of Dairy Science and Technology, Instituto del Frío (CSIC), José Antonio Nováis 10, 28040, Madrid, Spain
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Knockout of three-component regulatory systems reveals that the apparently constitutive plantaricin-production phenotype shown by Lactobacillus plantarum on solid medium is regulated via quorum sensing. Int J Food Microbiol 2009; 130:35-42. [DOI: 10.1016/j.ijfoodmicro.2008.12.033] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2008] [Revised: 12/22/2008] [Accepted: 12/28/2008] [Indexed: 11/20/2022]
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Kabuki T, Uenishi H, Seto Y, Yoshioka T, Nakajima H. A unique lantibiotic, thermophilin 1277, containing a disulfide bridge and two thioether bridges. J Appl Microbiol 2009; 106:853-62. [PMID: 19191960 DOI: 10.1111/j.1365-2672.2008.04059.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS To identify the chemical structure of a bacteriocin, thermophilin 1277, produced by Streptococcus thermophilus SBT1277. METHODS AND RESULTS Thermophilin 1277 was purified and partial N-terminal sequence analysis revealed 6 unidentified amino acids amongst 31 amino acids residues. A 2.7-kbp region containing the thermophilin 1277 structural gene (tepA) encoding 58 amino acids was cloned and sequenced. Mature thermophilin 1277 (33 amino acids) was preceded by a 25-amino acid putative leader peptide containing a double glycine cleavage motif. Peptide sequence analysis following chemical modification of thermophilin 1277 revealed that the Cys21 and Cys29 residues form a disulfide bridge and that Thr8 or Thr10 forms two 3-methyllanthionines with Cys13 or Cys32 via thioether bridges. Antimicrobial activity was disrupted by ethanethiol or reductive agent treatments, indicating that the internal amino acid modifications are crucial for the activity. CONCLUSIONS Thermophilin 1277 from Strep. thermophilus SBT1277 belongs to the class of AII-type lantibiotics that has a disulfide and two thioether bridges. SIGNIFICANCE AND IMPACT OF THE STUDY This is the first report of a lantibiotic produced by a GRAS species of Strep. thermophilus; thermophilin 1277 has a unique structure containing both a disulfide bridge and two thioether bridges that are crucial for its activity.
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Affiliation(s)
- T Kabuki
- Technology and Research Institute, Snow Brand Milk Products, Co. Ltd, Minamidai 1-1-2, Kawagoe, Japan.
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Jeon HJ, Noda M, Matoba Y, Kumagai T, Sugiyama M. Crystal structure and mutagenic analysis of a bacteriocin immunity protein, Mun-im. Biochem Biophys Res Commun 2008; 378:574-8. [PMID: 19061861 DOI: 10.1016/j.bbrc.2008.11.093] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2008] [Accepted: 11/18/2008] [Indexed: 10/21/2022]
Abstract
Bacteriocin-producing lactic acid bacteria (LAB) possess a self-protection factor, which is generally called an immunity protein. In this study, we determine the crystal structure of an immunity protein, designated Mun-im, which was classified into subgroup B immunity proteins for class IIa bacteriocins. The Mun-im protein takes a left-turning antiparallel four-helix bundle structure with the flexible N- and C-terminal parts. Although the amino acid sequences of the subgroup B immunity proteins are distinguished from those of the subgroup A, the core structure of Mun-im is well-superimposed with that of the subgroup A immunity protein, EntA-im, and the C-terminus of both proteins is flexible. However, the C-terminus of Mun-im is obviously shorter than that of the subgroup A. We found through mutagenic study of Mun-im that the C-terminus and the K86 residue on the helix 4 in the immunity protein molecule are important for expression of the immunity activity on the subgroup B immunity proteins.
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Affiliation(s)
- Hyung Joon Jeon
- Department of Molecular Microbiology and Biotechnology, Graduate School of Biomedical Sciences, Hiroshima University, Kasumi 1-2-3, Minami-ku, Hiroshima 734-8551, Japan
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Diversity of Lactobacillus sakei strains investigated by phenotypic and genotypic methods. Syst Appl Microbiol 2008; 31:393-403. [DOI: 10.1016/j.syapm.2008.06.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Accepted: 06/25/2008] [Indexed: 11/21/2022]
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45
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Improvement of Raw Sausage Fermentation by Stress-Conditioning of the Starter Organism Lactobacillus sakei. Curr Microbiol 2008; 57:490-6. [DOI: 10.1007/s00284-008-9274-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2008] [Accepted: 07/01/2008] [Indexed: 10/21/2022]
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46
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Mutational analysis of the class IIa bacteriocin curvacin A and its orientation in target cell membranes. Appl Environ Microbiol 2008; 74:6766-73. [PMID: 18791005 DOI: 10.1128/aem.01068-08] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To analyze the orientation in target cell membranes of the pediocin-like bacteriocin (antimicrobial peptide) curvacin A, 55 variants were generated by site-directed mutagenesis and their potencies against four different target cells determined. The result suggest that the somewhat hydrophilic short central helix (residues 19 to 24), along with the N-terminal beta-sheet-like structure (residues 1 to 16), inserts in the interface region of the target cell membrane, with Ala22 close to the hydrophobic core of the membrane. The following hinge region, with Gly28 as an important residue, may then form a turn wherein Gly28 becomes positioned near the border between the interface and the hydrophobic regions, thus permitting the longer and more-hydrophobic C-terminal helix (residues 29 to 41) to insert into the hydrophobic core of the membrane. This helix contains three glycine residues (G33, G37, and G40) that form a putative helix-helix-interacting GxxxGxxG motif. The replacement of any of these glycines with a larger residue was very detrimental, suggesting their possible involvement in helix-helix interactions with a membrane-embedded receptor protein.
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Halbmayr E, Mathiesen G, Nguyen TH, Maischberger T, Peterbauer CK, Eijsink VGH, Haltrich D. High-level expression of recombinant beta-galactosidases in Lactobacillus plantarum and Lactobacillus sakei using a Sakacin P-based expression system. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2008; 56:4710-4719. [PMID: 18512940 DOI: 10.1021/jf073260+] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
This work presents the cloning and expression of the genes encoding heterodimeric beta-galactosidases from Lactobacillus reuteri L103, Lactobacillus acidophilus R22, Lactobacillus plantarum WCFS1, and Lactobacillus sakei Lb790. These enzymes consist of two subunits of approximately 73 and 35 kDa, which are encoded by two overlapping genes, lacL and lacM, respectively. We have cloned these genes into the lactobacillal expression vectors pSIP403 and pSIP409, which are based on the sakacin P operon of L. sakei ( Sørvig et al. Microbiology 2005, 151, 2439- 2449 ), and expressed them in the host strains L. plantarum WCFS1 and L. sakei Lb790. Results varied considerably, ranging from 2.23 to 61.1 U/mg of beta-galactosidase activity, depending on the origin of the lacLM genes, the host strain, and the expression vector used. Highest expression levels were obtained in a laboratory cultivation of L. plantarum WCFS1 harboring the plasmid pEH3R containing the lacLM gene from L. reuteri L103. These cultivations yielded approximately 23 000 U of beta-galactosidase activity per liter, corresponding to the formation of roughly 100 mg of recombinant protein per liter of fermentation medium, and beta-galactosidase levels amounted to 55% of the total intracellular protein of the host organism. To further verify the suitability of this expression system, recombinant beta-galactosidase from L. reuteri was purified to apparent homogeneity. The properties of the purified enzyme were essentially identical with the properties of purified native beta-galactosidase from L. reuteri L103. The presented results lead the way to efficient overproduction of beta-galactosidase in a food-grade expression system, which is of high interest for applications in food industry.
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Affiliation(s)
- Elisabeth Halbmayr
- Division of Food Biotechnology, Department of Food Sciences and Technology, BOKU University of Natural Resources and Applied Life Sciences Vienna, Muthgasse 18, A-1190 Vienna, Austria
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Martin-Visscher LA, Sprules T, Gursky LJ, Vederas JC. Nuclear magnetic resonance solution structure of PisI, a group B immunity protein that provides protection against the type IIa bacteriocin piscicolin 126, PisA. Biochemistry 2008; 47:6427-36. [PMID: 18500825 DOI: 10.1021/bi8004076] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Lactic acid bacteria produce and secrete bacteriocins. These bacteriocins are potent antimicrobial peptides that are active against other closely related bacteria. As a means of self-protection, producer organisms also express immunity proteins. Immunity proteins are generally located on the same genetic locus and are cotranscribed with the bacteriocin. Although some cross immunity between bacteriocins has been observed, immunity proteins are typically highly specific. Immunity proteins for the type IIa bacteriocins range from 81 to 115 amino acids in length and display substantial variation in their sequences. Nonetheless, such immunity proteins have been classified into three groupings (groups A, B, and C) according to sequence homology. The structures of a group C (ImB2) and two group A (EntA-im and PedB) immunity proteins have previously been reported. We herein report the nuclear magnetic resonance solution structure of the remaining class of the type IIa immunity proteins. PisI, a 98-amino acid protein, is a group B immunity protein conferring immunity against piscicolin 126 (PisA). Like ImB2, EntA-im, and PedB, PisI folds into a globular protein in aqueous solution and contains an antiparallel four-helix bundle. Compared to ImB2 and EntA-im, PisI has a substantially longer and more flexible N-terminus, but a shorter C-terminus. No direct interaction between the bacteriocin and immunity protein is observed by NMR in either aqueous or membrane mimicking environments. This further suggests that the mechanism that mediates immunity is not due to a direct bacteriocin-immunity protein interaction but rather is receptor-mediated. It has now been confirmed that the four-helix bundle is indeed a structural motif among the type IIa immunity proteins.
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Oppegård C, Schmidt J, Kristiansen PE, Nissen-Meyer J. Mutational analysis of putative helix-helix interacting GxxxG-motifs and tryptophan residues in the two-peptide bacteriocin lactococcin G. Biochemistry 2008; 47:5242-9. [PMID: 18407666 DOI: 10.1021/bi800289w] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The membrane-permeabilizing two-peptide bacteriocin lactococcin G consists of two different peptides, LcnG-alpha and LcnG-beta. The bacteriocin contains several tryptophan and tyrosine residues and three putative helix-helix interacting GxxxG-motifs, G 7xxxG 11 and G 18xxxG 22 in LcnG-alpha and G 18xxxG 22 in LcnG-beta. The tryptophan and tyrosine residues and residues in the GxxxG-motifs were altered by site-directed mutagenesis to analyze the structure and membrane-orientation of lactococcin G. Substituting the glycine residues at position 7 or 11 in the G 7xxxG 11-motif in LcnG-alpha with large hydrophobic or hydrophilic residues was highly detrimental, whereas small residues were tolerated. Qualitatively similar results were obtained for the G 18xxxG 22-motif in LcnG-beta. In contrast, replacement of the glycine residues in the middle of these two motifs with large hydrophilic residues was tolerated. All mutations in the G 18xxxG 22-motif in LcnG-alpha were relatively well-tolerated, indicating that this motif is not involved in helix-helix interactions. The four aromatic residues in the N-terminal part of LcnG-beta could individually be replaced by other aromatic residues, a hydrophilic positive residue, and a hydrophobic residue without a marked reduced activity, indicating that this region is structurally flexible and not embedded in a strictly hydrophobic or hydrophilic environment. The results are in accordance with a structural model where the G 7xxxG 11-motif in LcnG-alpha and the G 18xxxG 22-motif in LcnG-beta interact and allow the two peptides to form a parallel transmembrane helix-helix structure, with the tryptophan-rich N-terminal part of LcnG-beta positioned in the outer membrane interface and the cationic C-terminal end of LcnG-alpha inside the cell.
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Affiliation(s)
- Camilla Oppegård
- Department of Molecular Biosciences, University of Oslo, Pb 1041 Blindern, 0316 Oslo, Norway.
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van Belkum MJ, Derksen DJ, Franz CMAP, Vederas JC. Structure function relationship of inducer peptide pheromones involved in bacteriocin production in Carnobacterium maltaromaticum and Enterococcus faecium. MICROBIOLOGY-SGM 2008; 153:3660-3666. [PMID: 17975073 DOI: 10.1099/mic.0.2007/009183-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The production of several bacteriocins in lactic acid bacteria is regulated by inducer peptide pheromones that specifically interact with their cognate bacterial receptor. These peptide pheromones are between 19 and 27 aa long and contain a conserved (V/I)-X-X-X-F sequence followed by positively charged residues in the C-terminal domain. CbaX and EntF are peptide pheromones that share similarity and are involved in the production of carnobacteriocin A in Carnobacterium maltaromaticum LV17A and enterocins A and B in Enterococcus faecium CTC492, respectively. CbaX, EntF and two hybrids, CbaX::EntF and EntF::CbaX, were tested for pheromone activity in LV17A and CTC492. EntF and EntF::CbaX only induced bacteriocin production in CTC492, whereas CbaX and CbaX::EntF induced carnobacteriocin A production in LV17A and, at high concentrations, also cross-induced enterocin production in CTC492. Various peptide fragments of CbaX and EntF were made for further structure-function analysis. The C-terminal fragments, but not the N-terminal fragments, were able to effect bacteriocin induction. The 10-mer EntF(16-25), derived from the C-terminal domain of EntF, showed pheromone activity in LV17A. In contrast, the C-terminal 9-mer of CbaX, CbaX(16-24), inhibited pheromone activity in both LV17A and CTC492. EntF(16-25) and CbaX(16-24) differ by two amino acids. Changing either one of these abolished pheromone activity as well as the ability to inhibit pheromone activity. These results indicate that the C-terminal domain of these peptide pheromones interacts relatively non-specifically with the receptor, and that induction is greatly facilitated by the N-terminal domain that recognizes specifically its cognate receptor.
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Affiliation(s)
- Marco J van Belkum
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada
| | - Darren J Derksen
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada
| | - Charles M A P Franz
- Federal Research Centre for Nutrition and Food, Institute of Hygiene and Toxicology, Haid-und-Neu-Strasse 9, D-76131 Karlsruhe, Germany
| | - John C Vederas
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada
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