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Alippi AM, Lamelza F, Torres Tejerizo GA, Abrahamovich E, López AC. Identification, phylogenetic analysis, and genome mining of the tetracycline-resistant Bacillus thuringiensis strain m401 reveal its potential for biotechnological and biocontrol applications. Rev Argent Microbiol 2023; 55:317-331. [PMID: 37400312 DOI: 10.1016/j.ram.2023.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 04/03/2023] [Accepted: 05/22/2023] [Indexed: 07/05/2023] Open
Abstract
Bacillus thuringiensis is an entomopathogen belonging to the Bacillus cereus clade. We isolated a tetracycline-resistant strain called m401, recovered it from honey, and identified it as Bacillus thuringiensis sv. kumamotoensis based on the average nucleotide identity calculations (ANIb) comparison and the analysis of the gyrB gene sequences of different B. thuringiensis serovars. Sequences with homology to virulence factors [cytK, nheA, nheB, nheC, hblA, hblB, hblC, hblD, entFM, and inhA] and tetracycline resistance genes [tet(45), tet(V), and tet(M)/tet(W)/tet(O)/tet(S) family] were identified in the bacterial chromosome. The prediction of plasmid-coding regions revealed homolog sequences to the MarR and TetR/AcrR family of transcriptional regulators, toxins, and lantipeptides. The genome mining analysis revealed 12 regions of biosynthetic gene clusters responsible for synthesizing secondary metabolites. We identified biosynthetic gene clusters coding for bacteriocins, siderophores, ribosomally synthesized post-translationally modified peptide products, and non-ribosomal peptide synthetase clusters that provide evidence for the possible use of Bt m401 as a biocontrol agent. Furthermore, Bt m401 showed high inhibition against all Paenibacillus larvae genotypes tested in vitro. In conclusion, Bt m401 owns various genes involved in different biological processes, such as transductional regulators associated with antibiotic resistance, toxins, and antimicrobial peptides with potential biotechnological and biocontrol applications.
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Affiliation(s)
- Adriana M Alippi
- Unidad de Bacteriología, Centro de Investigaciones de Fitopatología (CIDEFI), Facultad de Ciencias Agrarias y Forestales, Universidad Nacional de La Plata, cc 31, calle 60 y 119, S/N, 1900 La Plata, Argentina; Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CICBA), Argentina.
| | - Florencia Lamelza
- Unidad de Bacteriología, Centro de Investigaciones de Fitopatología (CIDEFI), Facultad de Ciencias Agrarias y Forestales, Universidad Nacional de La Plata, cc 31, calle 60 y 119, S/N, 1900 La Plata, Argentina
| | - Gonzalo A Torres Tejerizo
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET-CCT La Plata), Argentina; IBBM (Instituto de Biotecnología y Biología Molecular), Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, UNLP, Calles 49 y 115 S/N, 1900 La Plata, Argentina
| | - Eliana Abrahamovich
- YPF Tecnología (Y-Tec), Av. del Petróleo S/N entre 129 y 143, 1923 Berisso, Argentina
| | - Ana C López
- Unidad de Bacteriología, Centro de Investigaciones de Fitopatología (CIDEFI), Facultad de Ciencias Agrarias y Forestales, Universidad Nacional de La Plata, cc 31, calle 60 y 119, S/N, 1900 La Plata, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET-CCT La Plata), Argentina
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Hinnekens P, Fayad N, Gillis A, Mahillon J. Conjugation across Bacillus cereus and kin: A review. Front Microbiol 2022; 13:1034440. [PMID: 36406448 PMCID: PMC9673590 DOI: 10.3389/fmicb.2022.1034440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 10/11/2022] [Indexed: 11/06/2022] Open
Abstract
Horizontal gene transfer (HGT) is a major driving force in shaping bacterial communities. Key elements responsible for HGT are conjugation-like events and transmissible plasmids. Conjugative plasmids can promote their own transfer as well as that of co-resident plasmids. Bacillus cereus and relatives harbor a plethora of plasmids, including conjugative plasmids, which are at the heart of the group species differentiation and specification. Since the first report of a conjugation-like event between strains of B. cereus sensu lato (s.l.) 40 years ago, many have studied the potential of plasmid transfer across the group, especially for plasmids encoding major toxins. Over the years, more than 20 plasmids from B. cereus isolates have been reported as conjugative. However, with the increasing number of genomic data available, in silico analyses indicate that more plasmids from B. cereus s.l. genomes present self-transfer potential. B. cereus s.l. bacteria occupy diverse environmental niches, which were mimicked in laboratory conditions to study conjugation-related mechanisms. Laboratory mating conditions remain nonetheless simplistic compared to the complex interactions occurring in natural environments. Given the health, economic and ecological importance of strains of B. cereus s.l., it is of prime importance to consider the impact of conjugation within this bacterial group.
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Affiliation(s)
- Pauline Hinnekens
- Laboratory of Food and Environmental Microbiology, Earth and Life Institute, Louvain-la-Neuve, Belgium
| | - Nancy Fayad
- Multi-Omics Laboratory, School of Pharmacy, Lebanese American University, Byblos, Lebanon
| | - Annika Gillis
- Laboratory of Food and Environmental Microbiology, Earth and Life Institute, Louvain-la-Neuve, Belgium
| | - Jacques Mahillon
- Laboratory of Food and Environmental Microbiology, Earth and Life Institute, Louvain-la-Neuve, Belgium
- *Correspondence: Jacques Mahillon,
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M N, G S S, J S, K H, C S, P M, R N, C P S, N C, Ram B, C A, B S. Whole genome analysis and functional characterization of a novel Bacillus thuringiensis (Bt 62) isolate against sugarcane white grub Holotrichia serrata (F). Genomics 2021; 114:185-195. [PMID: 34933070 DOI: 10.1016/j.ygeno.2021.12.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 01/18/2021] [Accepted: 12/15/2021] [Indexed: 11/19/2022]
Abstract
In this study, we report the whole genome assembly of Bt 62, a novel isolate harbouring cry8 holotype gene identified by us earlier. Sequencing was carried out using a combination of Illumina NextSeq 500 and Oxford Nanopore sequencing Technologies (ONT). The final assembled genome was 6.13 Mb comprising a circular chromosome and four plasmids. The bioassay studies against Holotrichia serrata (F.) (Coleoptera: Scarabaeidae), a polyphagous pest infesting sugarcane and other crops, indicated significant toxicity to first instar grubs over untreated larvae achieving a highest mean mortality of 91.11% for various doses tested. In vitro proteolytic assay and histopathological studies of the midgut of infected white grubs revealed proteolytic processing of the protoxin and extensive degeneration of larval midgut epithelial cells. The results demonstrate that this novel isolate could be used as a biopesticide or its crystal toxin genes could be expressed in sugarcane and other crops for resistance against H. serrata.
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Affiliation(s)
- Naveenarani M
- ICAR- Sugarcane Breeding Institute, Coimbatore, Tamil Nadu 641007, India
| | - Suresha G S
- ICAR- Sugarcane Breeding Institute, Coimbatore, Tamil Nadu 641007, India
| | - Srikanth J
- ICAR- Sugarcane Breeding Institute, Coimbatore, Tamil Nadu 641007, India
| | - Hari K
- ICAR- Sugarcane Breeding Institute, Coimbatore, Tamil Nadu 641007, India
| | - Sankaranarayanan C
- ICAR- Sugarcane Breeding Institute, Coimbatore, Tamil Nadu 641007, India
| | - Mahesh P
- ICAR- Sugarcane Breeding Institute, Coimbatore, Tamil Nadu 641007, India
| | - Nirmala R
- ICAR- Sugarcane Breeding Institute, Coimbatore, Tamil Nadu 641007, India
| | - Swathik C P
- ICAR- Sugarcane Breeding Institute, Coimbatore, Tamil Nadu 641007, India
| | - Crickmore N
- School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, UK
| | - Bakshi Ram
- ICAR- Sugarcane Breeding Institute, Coimbatore, Tamil Nadu 641007, India
| | - Appunu C
- ICAR- Sugarcane Breeding Institute, Coimbatore, Tamil Nadu 641007, India
| | - Singaravelu B
- ICAR- Sugarcane Breeding Institute, Coimbatore, Tamil Nadu 641007, India.
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Sha Y, Zhang Y, Qiu Y, Xu Z, Li S, Feng X, Wang M, Xu H. Efficient Biosynthesis of Low-Molecular-Weight Poly-γ-glutamic Acid by Stable Overexpression of PgdS Hydrolase in Bacillus amyloliquefaciens NB. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:282-290. [PMID: 30543111 DOI: 10.1021/acs.jafc.8b05485] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Low-molecular-weight poly-γ-glutamic acid (LMW-γ-PGA) has attracted much attention owing to its great potential in food, agriculture, medicine, and cosmetics. Current methods of LMW-γ-PGA production, including enzymatic hydrolysis, are associated with low operational stability. Here, an efficient method for stable biosynthesis of LMW-γ-PGA was conceived by overexpression of γ-PGA hydrolase in Bacillus amyloliquefaciens NB. To establish stable expression of γ-PGA hydrolase (PgdS) during fermentation, a novel plasmid pNX01 was constructed with a native replicon from endogenous plasmid p2Sip, showing a loss rate of 4% after 100 consecutive passages. Subsequently, this plasmid was applied in a screen of high activity PgdS hydrolase, leading to substantial improvements to γ-PGA titer with concomitant decrease in the molecular weight. Finally, a satisfactory yield of 17.62 ± 0.38 g/L LMW-γ-PGA with a weight-average molecular weight of 20-30 kDa was achieved by direct fermentation of Jerusalem artichoke tuber extract. Our study presents a potential method for commercial production of LMW-γ-PGA.
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Affiliation(s)
- Yuanyuan Sha
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , China
| | - Yatao Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , China
| | - Yibin Qiu
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , China
| | - Zongqi Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , China
| | - Sha Li
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , China
| | - Xiaohai Feng
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , China
| | - Mingxuan Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , China
| | - Hong Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , China
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Gillis A, Fayad N, Makart L, Bolotin A, Sorokin A, Kallassy M, Mahillon J. Role of plasmid plasticity and mobile genetic elements in the entomopathogen Bacillus thuringiensis serovar israelensis. FEMS Microbiol Rev 2018; 42:829-856. [PMID: 30203090 PMCID: PMC6199540 DOI: 10.1093/femsre/fuy034] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Accepted: 09/06/2018] [Indexed: 12/14/2022] Open
Abstract
Bacillus thuringiensis is a well-known biopesticide that has been used for more than 80 years. This spore-forming bacterium belongs to the group of Bacillus cereus that also includes, among others, emetic and diarrheic pathotypes of B. cereus, the animal pathogen Bacillus anthracis and the psychrotolerant Bacillus weihenstephanensis. Bacillus thuringiensis is rather unique since it has adapted its lifestyle as an efficient pathogen of specific insect larvae. One of the peculiarities of B. thuringiensis strains is the extent of their extrachromosomal pool, with strains harbouring more than 10 distinct plasmid molecules. Among the numerous serovars of B. thuringiensis, 'israelensis' is certainly emblematic since its host spectrum is apparently restricted to dipteran insects like mosquitoes and black flies, vectors of human and animal diseases such as malaria, yellow fever, or river blindness. In this review, the putative role of the mobile gene pool of B. thuringiensis serovar israelensis in its pathogenicity and dedicated lifestyle is reviewed, with specific emphasis on the nature, diversity, and potential mobility of its constituents. Variations among the few related strains of B. thuringiensis serovar israelensis will also be reported and discussed in the scope of this specialised insect pathogen, whose lifestyle in the environment remains largely unknown.
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Affiliation(s)
- Annika Gillis
- Laboratory of Food and Environmental Microbiology, Université catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium
| | - Nancy Fayad
- Laboratory of Food and Environmental Microbiology, Université catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium
- Laboratory of Biodiversity and Functional Genomics (BGF), Faculty of Sciences, Université Saint-Joseph, 1107 2050 Beirut, Lebanon
| | - Lionel Makart
- Laboratory of Food and Environmental Microbiology, Université catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium
| | - Alexander Bolotin
- UMR1319 Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, F-78350 Jouy-en-Josas, France
| | - Alexei Sorokin
- UMR1319 Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, F-78350 Jouy-en-Josas, France
| | - Mireille Kallassy
- Laboratory of Biodiversity and Functional Genomics (BGF), Faculty of Sciences, Université Saint-Joseph, 1107 2050 Beirut, Lebanon
| | - Jacques Mahillon
- Laboratory of Food and Environmental Microbiology, Université catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium
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Abstract
We report here the complete annotated 6,035,547-bp draft genome sequence of Bacillus thuringiensis INTA Fr7-4. This strain contains three cry8 and two vip1 and vip2 insecticidal toxin genes.
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Navas LE, Amadio AF, Ortiz EM, Sauka DH, Benintende GB, Berretta MF, Zandomeni RO. Complete Sequence and Organization of pFR260, the Bacillus thuringiensis INTA Fr7-4 Plasmid Harboring Insecticidal Genes. J Mol Microbiol Biotechnol 2017; 27:43-54. [DOI: 10.1159/000451056] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 09/23/2016] [Indexed: 11/19/2022] Open
Abstract
We report the complete sequence and analysis of pFR260, a novel megaplasmid of 260,595 bp from the <i>Bacillus thuringiensis</i> strain INTA Fr7-4 isolated in Argentina. It carries 7 insecticidal genes: 3 <i>cry8</i> copies previously reported, 2 <i>vip1,</i> and 2 <i>vip2</i>. Also, it carries a gene encoding a putative atypical Cry protein. These genes are arranged in a region of approximately 105 kbp in size with characteristics of a pathogenicity island with a potential coleopteran-specific insecticide profile. DNA strand composition asymmetry, as determined by GC skew analysis, and the presence of a Rep protein involved in the initiation of replication suggest a bidirectional <i>theta</i> mechanism of replication. In addition, many genes involved in conjugation and a CRISPR-Cas system were detected. The pFR260 sequence was deposited in GenBank under accession number KX258624.
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Risks for public health related to the presence of Bacillus cereus and other Bacillus spp. including Bacillus thuringiensis in foodstuffs. EFSA J 2016. [DOI: 10.2903/j.efsa.2016.4524] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
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Riojas MA, Kiss K, McKee ML, Hazbón MH. Multiplex PCR for species-level identification of Bacillus anthracis and detection of pXO1, pXO2, and related plasmids. Health Secur 2015; 13:122-9. [PMID: 25813976 DOI: 10.1089/hs.2014.0056] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The Bacillus anthracis virulence plasmids pXO1 and pXO2 have critical implications for biosafety and select agent status. The proper identification and characterization of B. anthracis and its plasmid profile is important to the biodefense research community. Multiplex PCR was used to simultaneously detect a B. anthracis-specific chromosomal mutation, 4 targets distributed across pXO1, 3 targets distributed across pXO2, and highly conserved regions of the 16S gene, allowing an internal positive control for each sample. The multiplex PCR can produce as many as 9 easily separable and distinguishable amplicons, ranging in size from 188 to 555 bp. The PCR results were used to characterize DNA samples extracted from B. anthracis, other Bacillus species, and other bacterial species from many different genera. With the exception of 2 novel putative plasmids discovered, testing against inclusion and extensive exclusion panels showed 100% correlation to previously published and expected results. Upon testing 29 previously unpublished B. anthracis strains, 10 (34.5%) were pXO1(+)/pXO2(+), 9 (31.0%) were pXO1(+)/pXO2(-), 7 (24.1%) were pXO1(-)/pXO2(+), and 3 (10.3%) were pXO1(-)/pXO2(-). The present work presents a novel 9-target multiplex PCR assay capable of species-level identification of B. anthracis via a unique chromosomal marker and the detection of pXO1 and pXO2 via multiply redundant targets on each.
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Navas LE, Berretta MF, Pérez MP, Amadio AF, Ortiz EM, Sauka DH, Benintende GB, Zandomeni RO. Sequence and Expression of Two cry8 Genes from Bacillus thuringiensis INTA Fr7-4, a Native Strain from Argentina. J Mol Microbiol Biotechnol 2014; 24:241-8. [DOI: 10.1159/000365929] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Amadio AF, Navas LE, Sauka DH, Berretta MF, Benintende GB, Zandomeni RO. Identification, Cloning and Expression of an Insecticide cry8 Gene from Bacillusthuringiensis INTA Fr7-4. J Mol Microbiol Biotechnol 2013; 23:401-9. [DOI: 10.1159/000353206] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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González A, Rodríguez G, Bruzón RY, Díaz M, Companionis A, Menéndez Z, Gato R. Isolation and characterization of entomopathogenic bacteria from soil samples from the western region of Cuba. JOURNAL OF VECTOR ECOLOGY : JOURNAL OF THE SOCIETY FOR VECTOR ECOLOGY 2013; 38:46-52. [PMID: 23701606 DOI: 10.1111/j.1948-7134.2013.12007.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The use of insect pathogens is a viable alternative for insect control because of their relative specificity and lower environmental impact. The search for wild strains against dipterans could have an impact on mosquito control programs. We have made an extensive screening of soil in western Cuba to find bacteria with larvicidal activity against mosquitoes. A total of 150 soil samples were collected and isolates were identifying using the API 50 CHB gallery. Phenotypic characteristics were analyzed by hierarchical ascending classification. Quantitative bioassays were conducted under laboratory conditions following the World Health Organization protocol in order to ascertain the toxicity and efficacy of isolates. The protein profiles of the crystal components were determined by SDS-PAGE. Eight hundred and eighty-one bacterial isolates were obtained, and 13 isolates with entomopathogenic activity were isolated from nine samples. Nine isolates displayed higher entomopathogenic activity against both Cx. quinquefasciatus and Ae. aegypti compared with the reference strain 266/2. All toxic isolates showed higher biological potency than the 266/2 strain. These isolates with high entomopathogenic activity displayed a protein pattern similar to the B. thuringiensis var. israelensis IPS-82 and 266/2 strains. These results are a valuable tool for the control of Diptera of medical importance.
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Affiliation(s)
- Aileen González
- LABIOFAM, Havana, Cuba Department of Vector Control, Institute of Tropical Medicine Pedro Kourí, Havana Cuba, Marianao 13, Havana, Cuba.
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Characterization of plasmids in a human clinical strain of Lactococcus garvieae. PLoS One 2012; 7:e40119. [PMID: 22768237 PMCID: PMC3387028 DOI: 10.1371/journal.pone.0040119] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Accepted: 06/01/2012] [Indexed: 02/04/2023] Open
Abstract
The present work describes the molecular characterization of five circular plasmids found in the human clinical strain Lactococcus garvieae 21881. The plasmids were designated pGL1-pGL5, with molecular sizes of 4,536 bp, 4,572 bp, 12,948 bp, 14,006 bp and 68,798 bp, respectively. Based on detailed sequence analysis, some of these plasmids appear to be mosaics composed of DNA obtained by modular exchange between different species of lactic acid bacteria. Based on sequence data and the derived presence of certain genes and proteins, the plasmid pGL2 appears to replicate via a rolling-circle mechanism, while the other four plasmids appear to belong to the group of lactococcal theta-type replicons. The plasmids pGL1, pGL2 and pGL5 encode putative proteins related with bacteriocin synthesis and bacteriocin secretion and immunity. The plasmid pGL5 harbors genes (txn, orf5 and orf25) encoding proteins that could be considered putative virulence factors. The gene txn encodes a protein with an enzymatic domain corresponding to the family actin-ADP-ribosyltransferases toxins, which are known to play a key role in pathogenesis of a variety of bacterial pathogens. The genes orf5 and orf25 encode two putative surface proteins containing the cell wall-sorting motif LPXTG, with mucin-binding and collagen-binding protein domains, respectively. These proteins could be involved in the adherence of L. garvieae to mucus from the intestine, facilitating further interaction with intestinal epithelial cells and to collagenous tissues such as the collagen-rich heart valves. To our knowledge, this is the first report on the characterization of plasmids in a human clinical strain of this pathogen.
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