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Pérez JM, Jesser EN, Werdin JO, Berry C, Gebely MA, Crespo-Ginés R, Granados JE, López-Montoya AJ. In vitro acaricidal activity of several natural products against ibex-derived Sarcoptes scabiei. Vet Parasitol 2024; 328:110189. [PMID: 38714065 DOI: 10.1016/j.vetpar.2024.110189] [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: 02/08/2024] [Revised: 04/18/2024] [Accepted: 04/22/2024] [Indexed: 05/09/2024]
Abstract
In this study we analysed the effect of the temperature, diverse strains of Bacillus thuringiensis, Lysinibacillus sphaericus and nanoformulations with essential plant oils (EONP) on the survival of Sarcoptes scabiei mites derived from naturally-infested Iberian ibex (Capra pyrenaica). In general, mites maintained at 12ºC survived more than those maintained at 35ºC (40.7 hr and 31.2 hr, respectively). Mites with no treatment survived 27.6 h on average. Mites treated with B. thuringiensis serovar. konkukian and geranium EONP showed significant reduction in their survival. Despite the fact that these agents seem to be promising candidates for controlling sarcoptic mange in the field, further research is still needed to get stable, efficient and eco-friendly acaricides.
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Affiliation(s)
- Jesús M Pérez
- Departamento de Biología Animal, Vegetal y Ecología, Universidad de Jaén, Campus Las Lagunillas, s.n., Jaén E-23071, Spain.
| | - Emiliano N Jesser
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, San Juan 670, Bahía Blanca B 8000CPB, Argentina
| | - Jorge O Werdin
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, San Juan 670, Bahía Blanca B 8000CPB, Argentina
| | - Colin Berry
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK
| | - Mohamed A Gebely
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK; Department of Parasitology and Animal Diseases, Veterinary Research Institute, National Research Centre, Dokki, Giza 12622, Egypt
| | - Raquel Crespo-Ginés
- Departamento de Biología Animal, Vegetal y Ecología, Universidad de Jaén, Campus Las Lagunillas, s.n., Jaén E-23071, Spain; Instituto de Investigación en Recursos Cinegéticos (IREC-CSIC, UCLM, JCCM), Ronda de Toledo 12, Ciudad Real E-13071, Spain
| | - José E Granados
- Centro Administrativo Parque Nacional y Parque Natural Sierra Nevada, Carretera Antigua Sierra Nevada, Km 7, E-18071, Pinos Genil, Granada, Spain
| | - Antonio J López-Montoya
- Department of Statistics and Operational Research, Jaén University, Campus Las Lagunillas, s.n., Jaén E-23071, Spain
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Zhang L, Xu H, Cheng H, Song F, Zhang J, Peng Q. Transcriptional regulation of cellobiose utilization by PRD-domain containing Sigma54-dependent transcriptional activator (CelR) and catabolite control protein A (CcpA) in Bacillus thuringiensis. Front Microbiol 2024; 15:1160472. [PMID: 38357353 PMCID: PMC10864463 DOI: 10.3389/fmicb.2024.1160472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 01/16/2024] [Indexed: 02/16/2024] Open
Abstract
Cellobiose, a β-1,4-linked glucose dimer, is a major cellodextrin resulting from the enzymatic hydrolysis of cellulose. It is a major source of carbon for soil bacteria. In bacteria, the phosphoenolpyruvate (PEP): carbohydrate phosphotransferase system (PTS), encoded by the cel operon, is responsible for the transport and utilization of cellobiose. In this study, we analyzed the transcription and regulation of the cel operon in Bacillus thuringiensis (Bt). The cel operon is composed of five genes forming one transcription unit. β-Galactosidase assays revealed that cel operon transcription is induced by cellobiose, controlled by Sigma54, and positively regulated by CelR. The HTH-AAA+ domain of CelR recognized and specifically bound to three possible binding sites in the celA promoter region. CelR contains two PTS regulation domains (PRD1 and PRD2), which are separated by two PTS-like domains-the mannose transporter enzyme IIA component domain (EIIAMan) and the galactitol transporter enzyme IIB component domain (EIIBGat). Mutations of His-546 on the EIIAMan domain and Cys-682 on the EIIBGat domain resulted in decreased transcription of the cel operon, and mutations of His-839 on PRD2 increased transcription of the cel operon. Glucose repressed the transcription of the cel operon and catabolite control protein A (CcpA) positively regulated this process by binding the cel promoter. In the celABCDE and celR mutants, PTS activities were decreased, and cellobiose utilization was abolished, suggesting that the cel operon is essential for cellobiose utilization. Bt has been widely used as a biological pesticide. The metabolic properties of Bt are critical for fermentation. Nutrient utilization is also essential for the environmental adaptation of Bt. Glucose is the preferred energy source for many bacteria, and the presence of the phosphotransferase system allows bacteria to utilize other sugars in addition to glucose. Cellobiose utilization pathways have been of particular interest owing to their potential for developing alternative energy sources for bacteria. The data presented in this study improve our understanding of the transcription patterns of cel gene clusters. This will further help us to better understand how cellobiose is utilized for bacterial growth.
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Affiliation(s)
| | | | | | | | | | - Qi Peng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
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Rabha M, Das D, Konwar T, Acharjee S, Sarmah BK. Whole genome sequencing of a novel Bacillus thuringiensis isolated from Assam soil. BMC Microbiol 2023; 23:91. [PMID: 37003972 PMCID: PMC10064770 DOI: 10.1186/s12866-023-02821-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 03/13/2023] [Indexed: 04/03/2023] Open
Abstract
BACKGROUND Bacillus thuringiensis (Bt) is a gram-positive ubiquitous saprophytic bacterium that produces proteins (Crystal protein, Vegetative insecticidal protein, and Secreted insecticidal protein) toxic to insects during its growth cycle. In the present study, the whole genome of a locally isolated B. thuringiensis strain BA04 was sequenced to explore the genetic makeup and to identify the genes responsible to produce insecticidal proteins including the virulence factors. The strain was isolated from the soil sample of the Kaziranga National Park, Assam, North-Eastern part of India (Latitude: 26°34'39.11''N and Longitude: 93°10'16.04''E). RESULTS The whole genome sequencing (WGS) of the BA04 strain revealed that it has a circular genome of size 6,113,005 bp with four numbers of plasmids. A total of 6,111 genes including two novel crystal protein-encoding genes (MH753362.1 and MH753363.1) were identified. The BLASTn analysis of MH753362.1 showed 84% similarities (maximum identity) with Cry1Ia (KJ710646.1) gene, whereas MH753363.1 exhibited 66% identity with Insecticidal Crystal Protein (ICP)-6 gene (KM053257.1). At the protein level, MH753362.1 and MH753363.1 shared 79% identity with Cry1Ia (AIW52613.1) and 40% identity with Insecticidal Crystal Protein (ICP)-6 (AJW76687.1) respectively. Three-dimensional structures of these two novel protein sequences revealed that MH753362.1 have 48% structural similarity with Cry8ea1 protein, whereas MH753363.1 showed only 20% structural similarity with Cry4Aa protein. Apart from these insecticidal genes, the strain was also found to contain virulence and virulence-associated factors including the antibiotic resistance genes and Clustered regularly interspaced short palindromic repeat (CRISPR) sequences. CONCLUSION This is the first report on the whole genome sequence of Bt strain BA04 isolated from Assam, a North-Eastern state of India. The WGS of strain BA04 unveils the presence of two novel types of insecticidal crystal protein-encoding genes which can be used for the development of insect-resistant transgenic crops. Additionally, the strain could be used for the formulations of effective biopesticides. The WGS provides the fastest and cheapest platform for a better understanding of the genetic makeup of a strain and helps to explore the role of virulence genes in pathogenicity against the insect host.
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Affiliation(s)
- Mihir Rabha
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat-13, Assam, India
- Silkworm Pathology Section, Central Sericultural Research and Training Institute, Central Silk Board, Ministry of Textile, Govt of India, Berhampore, West Bengal, 7421 01, India
| | - Debajit Das
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat-13, Assam, India
- Department of Biotechnology-Northeast Centre for Agricultural Biotechnology (DBT-NECAB), Assam Agricultural University, Jorhat-13, Assam, India
| | - Trishna Konwar
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat-13, Assam, India
- Department of Biotechnology-Northeast Centre for Agricultural Biotechnology (DBT-NECAB), Assam Agricultural University, Jorhat-13, Assam, India
| | - Sumita Acharjee
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat-13, Assam, India.
- Department of Biotechnology-Northeast Centre for Agricultural Biotechnology (DBT-NECAB), Assam Agricultural University, Jorhat-13, Assam, India.
| | - Bidyut Kumar Sarmah
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat-13, Assam, India.
- Department of Biotechnology-Northeast Centre for Agricultural Biotechnology (DBT-NECAB), Assam Agricultural University, Jorhat-13, Assam, India.
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Bacilli in the International Space Station. Microorganisms 2022; 10:microorganisms10122309. [PMID: 36557562 PMCID: PMC9782108 DOI: 10.3390/microorganisms10122309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 11/15/2022] [Accepted: 11/18/2022] [Indexed: 11/23/2022] Open
Abstract
Astronauts remote from Earth, not least those who will inhabit the Moon or Mars, are vulnerable to disease due to their reduced immunity, isolation from clinical support, and the disconnect from any buffering capacity provided by the Earth. Here, we explore potential risks for astronaut health, focusing on key aspects of the biology of Bacillus anthracis and other anthrax-like bacilli. We examine aspects of Bacillus cereus group genetics in relation to their evolutionary biology and pathogenicity; a new clade of the Bacillus cereus group, close related to B. anthracis, has colonized the International Space Station (ISS), is still present, and could in theory at least acquire pathogenic plasmids from the other B. cereus group strains. The main finding is that the genomic sequence alignments of the B. cereus group ISS strains revealed a high sequence identity, indicating they originated from the same strain and that a close look to the genetic variations among the strains suggesting they lived, or they are living, in a vegetative form in the ISS enough time to accumulate genetic variations unique for each single strains.
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Mahdi I, Fahsi N, Hijri M, Sobeh M. Antibiotic resistance in plant growth promoting bacteria: A comprehensive review and future perspectives to mitigate potential gene invasion risks. Front Microbiol 2022; 13:999988. [PMID: 36204627 PMCID: PMC9530320 DOI: 10.3389/fmicb.2022.999988] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 08/25/2022] [Indexed: 11/26/2022] Open
Abstract
Plant growth-promoting bacteria (PGPB) are endowed with several attributes that can be beneficial for host plants. They opened myriad doors toward green technology approach to reduce the use of chemical inputs, improve soil fertility, and promote plants’ health. However, many of these PGPB harbor antibiotic resistance genes (ARGs). Less attention has been given to multi-resistant bacterial bioinoculants which may transfer their ARGs to native soil microbial communities and other environmental reservoirs including animals, waters, and humans. Therefore, large-scale inoculation of crops by ARGs-harboring bacteria could worsen the evolution and dissemination of antibiotic resistance and aggravate the negative impacts on such ecosystem and ultimately public health. Their introduction into the soil could serve as ARGs invasion which may inter into the food chain. In this review, we underscore the antibiotic resistance of plant-associated bacteria, criticize the lack of consideration for this phenomenon in the screening and application processes, and provide some recommendations as well as a regulation framework relating to the development of bacteria-based biofertilizers to aid maximizing their value and applications in crop improvement while reducing the risks of ARGs invasion.
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Affiliation(s)
- Ismail Mahdi
- Agrobiosciences Research Program, Mohammed VI Polytechnic University (UM6P), Ben Guerir, Morocco
| | - Nidal Fahsi
- Agrobiosciences Research Program, Mohammed VI Polytechnic University (UM6P), Ben Guerir, Morocco
| | - Mohamed Hijri
- Institut de Recherche en Biologie Végétale, Département de Sciences Biologiques, Université de Montréal, Montréal, QC, Canada
- African Genome Center, Mohammed VI Polytechnic University (UM6P), Ben Guerir, Morocco
- *Correspondence: Mohamed Hijri,
| | - Mansour Sobeh
- Agrobiosciences Research Program, Mohammed VI Polytechnic University (UM6P), Ben Guerir, Morocco
- Mansour Sobeh,
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Zorigt T, Furuta Y, Simbotwe M, Ochi A, Tsujinouchi M, Shawa M, Shimizu T, Isoda N, Enkhtuya J, Higashi H. Development of ELISA based on Bacillus anthracis capsule biosynthesis protein CapA for naturally acquired antibodies against anthrax. PLoS One 2021; 16:e0258317. [PMID: 34634075 PMCID: PMC8504768 DOI: 10.1371/journal.pone.0258317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 09/23/2021] [Indexed: 11/30/2022] Open
Abstract
Anthrax is a zoonotic disease caused by the gram-positive spore-forming bacterium Bacillus anthracis. Detecting naturally acquired antibodies against anthrax sublethal exposure in animals is essential for anthrax surveillance and effective control measures. Serological assays based on protective antigen (PA) of B. anthracis are mainly used for anthrax surveillance and vaccine evaluation. Although the assay is reliable, it is challenging to distinguish the naturally acquired antibodies from vaccine-induced immunity in animals because PA is cross-reactive to both antibodies. Although additional data on the vaccination history of animals could bypass this problem, such data are not readily accessible in many cases. In this study, we established a new enzyme-linked immunosorbent assay (ELISA) specific to antibodies against capsule biosynthesis protein CapA antigen of B. anthracis, which is non-cross-reactive to vaccine-induced antibodies in horses. Using in silico analyses, we screened coding sequences encoded on pXO2 plasmid, which is absent in the veterinary vaccine strain Sterne 34F2 but present in virulent strains of B. anthracis. Among the 8 selected antigen candidates, capsule biosynthesis protein CapA (GBAA_RS28240) and peptide ABC transporter substrate-binding protein (GBAA_RS28340) were detected by antibodies in infected horse sera. Of these, CapA has not yet been identified as immunoreactive in other studies to the best of our knowledge. Considering the protein solubility and specificity of B. anthracis, we prepared the C-terminus region of CapA, named CapA322, and developed CapA322-ELISA based on a horse model. Comparative analysis of the CapA322-ELISA and PAD1-ELISA (ELISA uses domain one of the PA) showed that CapA322-ELISA could detect anti-CapA antibodies in sera from infected horses but was non-reactive to sera from vaccinated horses. The CapA322-ELISA could contribute to the anthrax surveillance in endemic areas, and two immunoreactive proteins identified in this study could be additives to the improvement of current or future vaccine development.
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Affiliation(s)
- Tuvshinzaya Zorigt
- Division of Infection and Immunity, International Institute for Zoonosis Control (Former Research Center for Zoonosis Control), Hokkaido University, Sapporo, Japan
- Graduate School of Infectious Diseases, School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Yoshikazu Furuta
- Division of Infection and Immunity, International Institute for Zoonosis Control (Former Research Center for Zoonosis Control), Hokkaido University, Sapporo, Japan
- Graduate School of Infectious Diseases, School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Manyando Simbotwe
- Division of Infection and Immunity, International Institute for Zoonosis Control (Former Research Center for Zoonosis Control), Hokkaido University, Sapporo, Japan
| | - Akihiro Ochi
- Equine Research Institute, Japan Racing Association, Shimotsuke, Tochigi, Japan
| | - Mai Tsujinouchi
- Division of Infection and Immunity, International Institute for Zoonosis Control (Former Research Center for Zoonosis Control), Hokkaido University, Sapporo, Japan
| | - Misheck Shawa
- Division of Infection and Immunity, International Institute for Zoonosis Control (Former Research Center for Zoonosis Control), Hokkaido University, Sapporo, Japan
- Graduate School of Infectious Diseases, School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Tomoko Shimizu
- Division of Infection and Immunity, International Institute for Zoonosis Control (Former Research Center for Zoonosis Control), Hokkaido University, Sapporo, Japan
| | - Norikazu Isoda
- Laboratory of Microbiology, School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | | | - Hideaki Higashi
- Division of Infection and Immunity, International Institute for Zoonosis Control (Former Research Center for Zoonosis Control), Hokkaido University, Sapporo, Japan
- Graduate School of Infectious Diseases, School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
- * E-mail:
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Aregbesola OA, Kumar A, Mokoena MP, Olaniran AO. Classic Pentachlorophenol Hydroxylating Phenylalanine 4-Monooxygenase from Indigenous Bacillus tropicus Strain AOA-CPS1: Cloning, Overexpression, Purification, Characterization and Structural Homology Modelling. Appl Biochem Biotechnol 2021; 194:635-658. [PMID: 34417677 DOI: 10.1007/s12010-021-03645-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 08/10/2021] [Indexed: 11/22/2022]
Abstract
The metabolically promiscuous pentachlorophenol (PCP) hydroxylating Phe4MO (represented as CpsB) was detected, amplified (from the genome of Bacillus tropicus strain AOA-CPS1), cloned, overexpressed, purified and characterized here. The 1.755-kb gene cloned in the pET15b vector expressed a ≅ 64 kDa monomeric protein which was purified to homogeneity by single-step affinity chromatography, with a total yield of 82.1%. The optimum temperature and pH of the enzyme were found to be 30 °C and 7.0, respectively. CpsB showed functional stability between pH 6.0-7.5 and temperature 25-30 °C. The enzyme-substrate reaction kinetic studies showed the allosteric nature of the enzyme and followed pre-steady state using NADH as a co-substrate with apparent vmax, Km, kcat and kcat/Km values of 0.465 μM.s-1, 140 μM, 0.099 s-1 and 7.07 × 10-4 μM-1.s-1, respectively, for the substrate PCP. The in-gel trypsin digestion experiments and bioinformatic tools confirmed that the reported enzyme is a Phe4MO with multiple putative conserved domains and metal ion-binding site. Though Phe4MO has been reported to have a diverse catalytic function, here we report, for the first time, that it functions as a PCP dehalogenase or PCP-4-monooxygenase by hydroxylating PCP. Hence, the use of this enzyme may be further explored in the bioremediation of PCP and other related xenobiotics.
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Affiliation(s)
- Oladipupo A Aregbesola
- Discipline of Microbiology, School of Life Sciences, College of Agriculture, Engineering and Science, University of KwaZulu-Natal (Westville Campus), Private Bag X54001, Durban, 4000, South Africa
| | - Ajit Kumar
- Discipline of Microbiology, School of Life Sciences, College of Agriculture, Engineering and Science, University of KwaZulu-Natal (Westville Campus), Private Bag X54001, Durban, 4000, South Africa
| | - Mduduzi P Mokoena
- Discipline of Microbiology, School of Life Sciences, College of Agriculture, Engineering and Science, University of KwaZulu-Natal (Westville Campus), Private Bag X54001, Durban, 4000, South Africa
| | - Ademola O Olaniran
- Discipline of Microbiology, School of Life Sciences, College of Agriculture, Engineering and Science, University of KwaZulu-Natal (Westville Campus), Private Bag X54001, Durban, 4000, South Africa.
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8
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The Food Poisoning Toxins of Bacillus cereus. Toxins (Basel) 2021; 13:toxins13020098. [PMID: 33525722 PMCID: PMC7911051 DOI: 10.3390/toxins13020098] [Citation(s) in RCA: 99] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/14/2021] [Accepted: 01/25/2021] [Indexed: 12/13/2022] Open
Abstract
Bacillus cereus is a ubiquitous soil bacterium responsible for two types of food-associated gastrointestinal diseases. While the emetic type, a food intoxication, manifests in nausea and vomiting, food infections with enteropathogenic strains cause diarrhea and abdominal pain. Causative toxins are the cyclic dodecadepsipeptide cereulide, and the proteinaceous enterotoxins hemolysin BL (Hbl), nonhemolytic enterotoxin (Nhe) and cytotoxin K (CytK), respectively. This review covers the current knowledge on distribution and genetic organization of the toxin genes, as well as mechanisms of enterotoxin gene regulation and toxin secretion. In this context, the exceptionally high variability of toxin production between single strains is highlighted. In addition, the mode of action of the pore-forming enterotoxins and their effect on target cells is described in detail. The main focus of this review are the two tripartite enterotoxin complexes Hbl and Nhe, but the latest findings on cereulide and CytK are also presented, as well as methods for toxin detection, and the contribution of further putative virulence factors to the diarrheal disease.
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Yi Z, Zhang T, Xie J, Zhu Z, Luo S, Zhou K, Zhou P, Chen W, Zhao X, Sun Y, Xia L, Ding X. iTRAQ analysis reveals the effect of gabD and sucA gene knockouts on lysine metabolism and crystal protein formation in Bacillus thuringiensis. Environ Microbiol 2021; 23:2230-2243. [PMID: 33331075 DOI: 10.1111/1462-2920.15359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 12/08/2020] [Indexed: 11/27/2022]
Abstract
Lysine metabolism plays an important role in the formation of the insecticidal crystal proteins of Bacillus thuringiensis (Bt). The genes lam, gabD and sucA encode three key enzymes of the lysine metabolic pathway in Bt4.0718. The lam gene mainly affects the cell growth at stable period, negligibly affected sporulation and insecticidal crystal protein (ICP) production. While, the deletion mutant strains of the gabD and sucA genes showed that the growth, sporulation and crystal protein formation were inhibited, cells became slender, and insecticidal activity was significantly reduced. iTRAQ proteomics and qRT-PCR used to analyse the differentially expressed protein (DEP) between the two mutant strains and the wild type strain. The functions of DEPs were visualized and statistically classified, which affect bacterial growth and metabolism by regulating biological metabolism pathways: the major carbon metabolism pathways, amino acid metabolism, oxidative phosphorylation pathways, nucleic acid metabolism, fatty acid synthesis and peptidoglycan synthesis. The gabD and sucA genes in lysine metabolic pathway are closely related to the sporulation and crystal proteins formation. The effects of DEPs and functional genes on basic cellular metabolic pathways were studied to provide new strategies for the construction of highly virulent insecticidal strains, the targeted transformation of functional genes.
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Affiliation(s)
- Zixian Yi
- Hunan Provincial Key Laboratory for Microbial Molecular Biology, State Key Laboratory of Development Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, China
| | - Tong Zhang
- Hunan Provincial Key Laboratory for Microbial Molecular Biology, State Key Laboratory of Development Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, China
| | - Junyan Xie
- Hunan Provincial Key Laboratory for Microbial Molecular Biology, State Key Laboratory of Development Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, China
| | - Zirong Zhu
- Hunan Provincial Key Laboratory for Microbial Molecular Biology, State Key Laboratory of Development Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, China
| | - Sisi Luo
- Hunan Provincial Key Laboratory for Microbial Molecular Biology, State Key Laboratory of Development Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, China
| | - Kexuan Zhou
- Hunan Provincial Key Laboratory for Microbial Molecular Biology, State Key Laboratory of Development Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, China
| | - Pengji Zhou
- Hunan Provincial Key Laboratory for Microbial Molecular Biology, State Key Laboratory of Development Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, China
| | - Wenhui Chen
- Hunan Provincial Key Laboratory for Microbial Molecular Biology, State Key Laboratory of Development Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, China
| | - Xiaoli Zhao
- Hunan Provincial Key Laboratory for Microbial Molecular Biology, State Key Laboratory of Development Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, China
| | - Yunjun Sun
- Hunan Provincial Key Laboratory for Microbial Molecular Biology, State Key Laboratory of Development Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, China
| | - Liqiu Xia
- Hunan Provincial Key Laboratory for Microbial Molecular Biology, State Key Laboratory of Development Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, China
| | - Xuezhi Ding
- Hunan Provincial Key Laboratory for Microbial Molecular Biology, State Key Laboratory of Development Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, China
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A Bacillus Spore-Based Display System for Bioremediation of Atrazine. Appl Environ Microbiol 2020; 86:AEM.01230-20. [PMID: 32680864 DOI: 10.1128/aem.01230-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 07/10/2020] [Indexed: 11/20/2022] Open
Abstract
Owing to human activities, a large number of organic chemicals, including petroleum products, industrial solvents, pesticides, herbicides (including atrazine [ATR]), and pharmaceuticals, contaminate soil and aquatic environments. Remediation of these pollutants by conventional approaches is both technically and economically challenging. Bacillus endospores are highly resistant to most physical assaults and are capable of long-term persistence in soil. Spores can be engineered to express, on their surface, important enzymes for bioremediation purposes. We have developed a Bacillus thuringiensis spore platform system that can display a high density of proteins on the spore surface. The spore surface-tethered enzymes exhibit enhanced activity and stability relative to free enzymes in soil and water environments. In this study, we evaluated a B. thuringiensis spore display platform as a bioremediation tool against ATR. The Pseudomonas sp. strain ADP atzA determinant, an ATR chlorohydrolase important to the detoxification of ATR, was expressed as a fusion protein linked to the attachment domain of the BclA spore surface nap layer protein and expressed in B. thuringiensis Spores from this strain are decorated with AtzA N-terminally linked on the surface of the spores. The recombinant spores were assayed for ATR detoxification in liquid and soil environments, and enzyme kinetics and stability were assessed. We successfully demonstrated the utility of this spore-based enzyme display system to detoxify ATR in water and laboratory soil samples.IMPORTANCE Atrazine is one of the most widely applied herbicides in the U.S. midwestern states. The long environmental half-life of atrazine has contributed to the contamination of surface water and groundwater by atrazine and its chlorinated metabolites. The toxic properties of ATR have raised public health and ecological concerns. However, remediation of ATR by conventional approaches has proven to be costly and inefficient. We developed a novel B. thuringiensis spore platform system that is capable of long-term persistence in soil and can be engineered to surface express a high density of enzymes useful for bioremediation purposes. The enzymes are stably attached to the surface of the spore exosporium layer. The spore-based system will likely prove useful for remediation of other environmental pollutants as well.
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Baldwin VM. You Can't B. cereus - A Review of Bacillus cereus Strains That Cause Anthrax-Like Disease. Front Microbiol 2020; 11:1731. [PMID: 32973690 PMCID: PMC7468541 DOI: 10.3389/fmicb.2020.01731] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 07/02/2020] [Indexed: 12/15/2022] Open
Abstract
Emerging strains of Bacillus cereus, traditionally considered a self-limiting foodborne pathogen, have been associated with anthrax-like disease in mammals, including humans. The strains have emerged by divergent evolution and, as exchange of genetic material in the Bacillus genus occurs naturally, it is possible that further isolates will be identified in the future. The strains vary in their genotypes and phenotypes, combining traits of both B. cereus and B. anthracis species. Cases of anthrax-like disease associated with these strains result in similar symptoms and mortality rates as those caused by B. anthracis. The strains are susceptible to frontline antibiotics used in the treatment of anthrax and existing vaccines provide protection in animal models. The emergence of these strains has reignited the debate surrounding classification of the B. cereus sensu lato group and serves as a reminder that the field of medical microbiology is constantly changing and remains an important and ongoing area of research.
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12
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Brivio MF, Mastore M. When Appearance Misleads: The Role of the Entomopathogen Surface in the Relationship with Its Host. INSECTS 2020; 11:E387. [PMID: 32585858 PMCID: PMC7348879 DOI: 10.3390/insects11060387] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 06/18/2020] [Accepted: 06/20/2020] [Indexed: 12/14/2022]
Abstract
Currently, potentially harmful insects are controlled mainly by chemical synthetic insecticides, but environmental emergencies strongly require less invasive control techniques. The use of biological insecticides in the form of entomopathogenic organisms is undoubtedly a fundamental resource for the biological control of insect pests in the future. These infectious agents and endogenous parasites generally act by profoundly altering the host's physiology to death, but their success is closely related to the neutralization of the target insect's immune response. In general, entomopathogen parasites, entomopathogenic bacteria, and fungi can counteract immune processes through the effects of secretion/excretion products that interfere with and damage the cells and molecules typical of innate immunity. However, these effects are observed in the later stages of infection, whereas the risk of being recognized and neutralized occurs very early after penetration and involves the pathogen surface components and molecular architecture; therefore, their role becomes crucial, particularly in the earliest pathogenesis. In this review, we analyze the evasion/interference strategies that entomopathogens such as the bacterium Bacillus thuringiensis, fungi, nematocomplexes, and wasps implement in the initial stages of infection, i.e., the phases during which body or cell surfaces play a key role in the interaction with the host receptors responsible for the immunological discrimination between self and non-self. In this regard, these organisms demonstrate evasive abilities ascribed to their body surface and cell wall; it appears that the key process of these mechanisms is the capability to modify the surface, converting it into an immunocompatible structure, or interaction that is more or less specific to host factors.
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Affiliation(s)
- Maurizio Francesco Brivio
- Laboratory of Comparative Immunology and Parasitology, Department of Theoretical and Applied Sciences, University of Insubria, 21100 Varese, Italy;
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13
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Rapid Microscopic Detection of Bacillus anthracis by Fluorescent Receptor Binding Proteins of Bacteriophages. Microorganisms 2020; 8:microorganisms8060934. [PMID: 32575866 PMCID: PMC7356292 DOI: 10.3390/microorganisms8060934] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 06/18/2020] [Accepted: 06/19/2020] [Indexed: 12/19/2022] Open
Abstract
Bacillus anthracis, the etiological agent of anthrax disease, is typically diagnosed by immunological and molecular methods such as polymerase chain reaction (PCR). Alternatively, mass spectrometry techniques may aid in confirming the presence of the pathogen or its toxins. However, because of the close genetic relationship between B. anthracis and other members of the Bacillus cereus sensu lato group (such as Bacillus cereus or Bacillus thuringiensis) mis- or questionable identification occurs frequently. Also, bacteriophages such as phage gamma (which is highly specific for B. anthracis) have been in use for anthrax diagnostics for many decades. Here we employed host cell-specific receptor binding proteins (RBP) of (pro)-phages, also known as tail or head fibers, to develop a microscopy-based approach for the facile, rapid and unambiguous detection of B. anthracis cells. For this, the genes of (putative) RBP from Bacillus phages gamma, Wip1, AP50c and from lambdoid prophage 03 located on the chromosome of B. anthracis were selected. Respective phage genes were heterologously expressed in Escherichia coli and purified as fusions with fluorescent proteins. B. anthracis cells incubated with either of the reporter fusion proteins were successfully surface-labeled. Binding specificity was confirmed as RBP fusion proteins did not bind to most isolates of a panel of other B. cereus s.l. species or to more distantly related bacteria. Remarkably, RBP fusions detected encapsulated B. anthracis cells, thus RBP were able to penetrate the poly-γ-d-glutamate capsule of B. anthracis. From these results we anticipate this RBP-reporter assay may be useful for rapid confirmative identification of B. anthracis.
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A Survey of Antimicrobial Resistance Determinants in Category A Select Agents, Exempt Strains, and Near-Neighbor Species. Int J Mol Sci 2020; 21:ijms21051669. [PMID: 32121349 PMCID: PMC7084191 DOI: 10.3390/ijms21051669] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 02/25/2020] [Accepted: 02/26/2020] [Indexed: 01/02/2023] Open
Abstract
A dramatic increase in global antimicrobial resistance (AMR) has been well documented. Of particular concern is the dearth of information regarding the spectrum and prevalence of AMR within Category A Select Agents. Here, we performed a survey of horizontally and vertically transferred AMR determinants among Category A agents and their near neighbors. Microarrays provided broad spectrum screening of 127 Francisella spp., Yersinia spp., and Bacillus spp. strains for the presence/absence of 500+ AMR genes (or families of genes). Detecting a broad variety of AMR genes in each genus, microarray analysis also picked up the presence of an engineered plasmid in a Y. pestis strain. High resolution melt analysis (HRMA) was also used to assess the presence of quinolone resistance-associated mutations in 100 of these strains. Though HRMA was able to detect resistance-causing point mutations in B. anthracis strains, it was not capable of discriminating these point mutations from other nucleotide substitutions (e.g., arising from sequence differences in near neighbors). Though these technologies are well-established, to our knowledge, this is the largest survey of Category A agents and their near-neighbor species for genes covering multiple mechanisms of AMR.
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Transcription in the acetoin catabolic pathway is regulated by AcoR and CcpA in Bacillus thuringiensis. Microbiol Res 2020; 235:126438. [PMID: 32088504 DOI: 10.1016/j.micres.2020.126438] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 02/11/2020] [Accepted: 02/11/2020] [Indexed: 01/04/2023]
Abstract
Acetoin (3-hydroxy-2-butanone) is an important physiological metabolic product in many microorganisms. Acetoin breakdown is catalyzed by the acetoin dehydrogenase enzyme system (AoDH ES), which is encoded by acoABCL operon. In this study, we analyzed transcription and regulation of the aco operon in Bacillus thuringiensis (Bt). RT-PCR analysis revealed that acoABCL forms one transcriptional unit. The Sigma 54 controlled consensus sequence was located 12 bp from the acoA transcriptional start site (TSS). β-galactosidase assay revealed that aco operon transcription is induced by acetoin, controlled by sigma 54, and positively regulated by AcoR. The HTH domain of AcoR recognized and specifically bound to a 13-bp inverted repeat region that participates in 30-bp fragment mapping 81 bp upstream of the acoA TSS. The GAF domain in AcoR represses enhancer transcriptional activity at the acoA promoter. Transcriptions of the aco operon and acoR were repressed by glucose via CcpA, and CcpA specifically bound to sequences within the acoR promoter fragment. In the acoABCL and acoR mutants, acetoin use was abolished, suggesting that the aco operon is essential for utilization of acetoin. The data presented here improve our understanding of the regulation of the aco gene cluster in bacteria.
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Andreazza AP, Cardoso RLA, Cocco J, Guizelini D, Faoro H, Tadra-Sfeir MZ, Balsanelli E, Cruz LM, Fadel-Picheth CMT, Donatti L, Souza EM, Foerster LA, Pedrosa FO, Chubatsu LS. Genome Analysis of Entomopathogenic Bacillus sp. ABP14 Isolated from a Lignocellulosic Compost. Genome Biol Evol 2019; 11:1658-1662. [PMID: 31135033 PMCID: PMC6573470 DOI: 10.1093/gbe/evz114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/23/2019] [Indexed: 01/08/2023] Open
Abstract
We report the complete genome sequence of Bacillus sp. strain ABP14 isolated from lignocellulosic compost and selected by its ability in hydrolyzing carboxymethyl cellulose. This strain does not produce a Cry-like protein but showed an insecticidal activity against larvae of Anticarsia gemmatalis (Lepidoptera). Genome-based taxonomic analysis revealed that the ABP14 chromosome is genetically close to Bacillus thuringiensis serovar finitimus YBT020. ABP14 also carries one plasmid which showed no similarity with those from YBT020. Genome analysis of ABP14 identified unique genes related to cell surface structures, cell wall, metabolic competence, and virulence factors that may contribute for its survival and environmental adaptation, as well as its entomopathogenic activity.
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Affiliation(s)
- Ana Paula Andreazza
- Department of Biochemistry and Molecular Biology, Federal University of Paraná, Curitiba, Paraná, Brazil
| | - Rodrigo L A Cardoso
- Department of Biochemistry and Molecular Biology, Federal University of Paraná, Curitiba, Paraná, Brazil
| | - Jessica Cocco
- Department of Zoology, Federal University of Paraná, Curitiba, Paraná, Brazil
| | - Dieval Guizelini
- Laboratory of Bioinformatics, Professional and Technological Education Sector, Federal University of Paraná, Curitiba, Paraná , Brazil
| | - Helisson Faoro
- Carlos Chagas Institute, Fiocruz-PR, Curitiba, Paraná, Brazil
| | - Michelle Z Tadra-Sfeir
- Department of Biochemistry and Molecular Biology, Federal University of Paraná, Curitiba, Paraná, Brazil
| | - Eduardo Balsanelli
- Department of Biochemistry and Molecular Biology, Federal University of Paraná, Curitiba, Paraná, Brazil
| | - Leonardo M Cruz
- Department of Biochemistry and Molecular Biology, Federal University of Paraná, Curitiba, Paraná, Brazil
| | | | - Lucélia Donatti
- Department of Cellular Biology, Federal University of Paraná, Curitiba, Paraná, Brazil
| | - Emanuel M Souza
- Department of Biochemistry and Molecular Biology, Federal University of Paraná, Curitiba, Paraná, Brazil
| | - Luís A Foerster
- Department of Zoology, Federal University of Paraná, Curitiba, Paraná, Brazil
| | - Fabio O Pedrosa
- Department of Biochemistry and Molecular Biology, Federal University of Paraná, Curitiba, Paraná, Brazil
| | - Leda S Chubatsu
- Department of Biochemistry and Molecular Biology, Federal University of Paraná, Curitiba, Paraná, Brazil
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Wei S, Chelliah R, Park BJ, Kim SH, Forghani F, Cho MS, Park DS, Jin YG, Oh DH. Differentiation of Bacillus thuringiensis From Bacillus cereus Group Using a Unique Marker Based on Real-Time PCR. Front Microbiol 2019; 10:883. [PMID: 31114555 PMCID: PMC6503103 DOI: 10.3389/fmicb.2019.00883] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 04/05/2019] [Indexed: 11/13/2022] Open
Abstract
The efficiency of a novel biomarker (the transcriptional regulator, XRE) was tested and evaluated in differentiating Bacillus thuringiensis from Bacillus cereus group species in environmental and spiked samples based on PCR and real-time PCR. Totally 120 strains, representing two bacterial groups, B. cereus group and non-Bacillus sp., were used to evaluate the performance of XRE and crystal protein (cry2, an existing biomarker). Further, three diverse samples (kimbap, lettuce, and spinach) were inoculated with B. thuringiensis and prominent biomarkers XRE and cry2 were used as targets. Direct analysis of the detection results for the pure cultures of B. cereus group wild-types, references and type strains revealed an accuracy rate of 97.5% targeting XRE, and 83.3% targeting cry2. The real-time PCR was constructed with a R 2-value of 0.993. For the artificially contaminated samples, a concentration of 103 CFU/g of B. thuringiensis in spiked food samples could be detected using real-time PCR targeting XRE. A good performance was obtained with XRE in discriminating B. thuringiensis from B. cereus groups, as well as detecting B. thuringiensis in spiked food samples with PCR or real-time PCR. Therefore, this real-time PCR targeting XRE can be used as a dependable and promising tool to identify B. thuringiensis in foods.
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Affiliation(s)
- Shuai Wei
- Department of Medical Biomaterials Engineering, Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon, South Korea
| | - Ramachandran Chelliah
- Department of Food Science and Biotechnology, Kangwon National University, Chuncheon, South Korea
| | - Byung-Jae Park
- Department of Food Science and Biotechnology, Kangwon National University, Chuncheon, South Korea
| | - Se-Hun Kim
- Department of Food Science and Biotechnology, Kangwon National University, Chuncheon, South Korea
| | - Fereidoun Forghani
- Center for Food Safety, College of Agricultural and Environmental Sciences, University of Georgia, Griffin, GA, United States
| | - Min Seok Cho
- Department of Agricultural Biotechnology, National Academy of Agricultural Science, Rural Development Administration, Jeonju, South Korea
| | - Dong-Suk Park
- Department of Agricultural Biotechnology, National Academy of Agricultural Science, Rural Development Administration, Jeonju, South Korea
| | - Yong-Guo Jin
- National Research and Development Center for Egg Processing, College of Food Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Deog-Hwan Oh
- Department of Food Science and Biotechnology, Kangwon National University, Chuncheon, South Korea
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18
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Genes under positive selection in the core genome of pathogenic Bacillus cereus group members. INFECTION GENETICS AND EVOLUTION 2018; 65:55-64. [PMID: 30006047 DOI: 10.1016/j.meegid.2018.07.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 07/06/2018] [Accepted: 07/07/2018] [Indexed: 11/24/2022]
Abstract
In this comparative genomics study our aim was to unravel genes under positive selection in the core genome of the Bacillus cereus group. Indeed, the members of this group share close genetic relationships but display a rather large phenotypic and ecological diversity, providing a unique opportunity for studying how genomic changes reflect ecological adaptation during the divergence of a bacterial group. For this purpose, we screened ten completely sequenced genomes of four pathogenic Bacillus species, finding that 254 out of 3093 genes have codon sites with dN/dS (ω) values above one. These results remained unchanged after having disentangled the confounding effects of recombination and selection signature in a Bayesian framework. The presumably adaptive nucleotide polymorphisms are distributed over a wide range of biological functions, such as antibiotic resistance, DNA repair, nutrient uptake, metabolism, cell wall assembly and spore structure. Our results indicate that adaptation to animal hosts, whether as pathogens, saprophytes or symbionts, is the major driving force in the evolution of the Bacillus cereus group. Future work should seek to understand the evolutionary dynamics of both core and accessory genes in an integrative framework to ultimately unravel the key networks involved in host adaptation.
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Rabha M, Acharjee S, Sarmah BK. Multilocus sequence typing for phylogenetic view and vip gene diversity of Bacillus thuringiensis strains of the Assam soil of North East India. World J Microbiol Biotechnol 2018; 34:103. [PMID: 29951787 DOI: 10.1007/s11274-018-2489-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 06/21/2018] [Indexed: 11/30/2022]
Abstract
An agriculturally important insecticidal bacterium, Bacillus thuringiensis have been isolated from the soil samples of various part of Assam including the Kaziranga National Park. Previously, the isolates were characterized based on morphology, 16S rDNA sequencing, and the presence of the various classes' crystal protein gene(s). In the present study, the phylogenetic analysis of a few selected isolates was performed by an unambiguous and quick method called the multiple locus sequence typing (MLST). A known B. thuringiensis strain kurstaki 4D4 have been used as a reference strain for MLST. A total of four the MLST locus of housekeeping genes, recF, sucC, gdpD and yhfL were selected. A total of 14 unique sequence types (STs) was identified. A total number of alleles identified for the locus gdpD and sucC was 12, followed by locus yhfL was 11, however, only 6 alleles were detected for the locus recF. The phylogenetic analysis using MEGA 7.0.26 showed three major lineages. Approximately, 87% of the isolates belonged to the STs corresponding to B. thuringiensis, whereas two isolates, BA07 and BA39, were clustered to B. cereus. The isolates were also screened for the diversity of vegetative insecticidal protein (vip) genes. In all, 8 isolates showed the presence of vip1, followed by 7 isolates having vip2 and 6 isolates for vip3 genes. The expression of Vip3A proteins was analyzed by western blot analyses and expression of the Vip3A protein was observed in the isolate BA20. Thus, the phylogenetic relationship and diversity of Bt isolates from Assam soil was established based on MLST, in addition, found isolates having vip genes, which could be used for crop improvement.
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Affiliation(s)
- Mihir Rabha
- Department of Agricultural Biotechnology, DBT-AAU Centre, Assam Agricultural University, Jorhat, Assam, 785013, India
| | - Sumita Acharjee
- Department of Agricultural Biotechnology, DBT-AAU Centre, Assam Agricultural University, Jorhat, Assam, 785013, India.
| | - Bidyut Kumar Sarmah
- Department of Agricultural Biotechnology, DBT-AAU Centre, Assam Agricultural University, Jorhat, Assam, 785013, India.
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Martin MS, Santos IC, Carlton DD, Stigler-Granados P, Hildenbrand ZL, Schug KA. Characterization of bacterial diversity in contaminated groundwater using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 622-623:1562-1571. [PMID: 29054663 DOI: 10.1016/j.scitotenv.2017.10.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 10/04/2017] [Accepted: 10/04/2017] [Indexed: 06/07/2023]
Abstract
Groundwater is a major source for drinking water in the United States, and therefore, its quality and quantity is of extreme importance. One major concern that has emerged is the possible contamination of groundwater due to the unconventional oil and gas extraction activities. As such, the impacts of exogenous contaminants on microbial ecology is an area to be explored to understand what are the chemical and physical conditions that allow the proliferation of pathogenic bacteria and to find alternatives for water treatment by identifying organic-degrading bacteria. In this work, we assess the interplay between groundwater quality and the microbiome in contaminated groundwaters rich in hydrocarbon gases, volatile organic and inorganic compounds, and various metals. Opportunistic pathogenic bacteria, such as Aeromonas hydrophila, Bacillus cereus, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia, were identified, increasing the risk for consumption of and exposure to these contaminated groundwaters. Additionally, antimicrobial tests revealed that many of the identified bacteria were resistant to different antibiotics. The MALDI-TOF MS results were successfully confirmed with 16S rRNA gene sequencing, proving the accuracy of this high-throughput method. Collectively, these data provide a seminal understanding of the microbial populations in contaminated groundwater overlying anthropogenic activities like unconventional oil and gas development.
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Affiliation(s)
- Misty S Martin
- Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX, USA
| | - Inês C Santos
- Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX, USA; Collaborative Laboratories for Environmental Analysis and Remediation, The University of Texas at Arlington, Arlington, TX, USA
| | - Doug D Carlton
- Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX, USA; Collaborative Laboratories for Environmental Analysis and Remediation, The University of Texas at Arlington, Arlington, TX, USA
| | | | - Zacariah L Hildenbrand
- Collaborative Laboratories for Environmental Analysis and Remediation, The University of Texas at Arlington, Arlington, TX, USA; Inform Environmental, LLC, Dallas, TX, USA.
| | - Kevin A Schug
- Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX, USA; Collaborative Laboratories for Environmental Analysis and Remediation, The University of Texas at Arlington, Arlington, TX, USA.
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Wang P, Zhu Y, Shang H, Deng Y, Sun M. A minireplicon of plasmid pBMB26 represents a new typical replicon in the megaplasmids of Bacillus cereus group. J Basic Microbiol 2017; 58:263-272. [PMID: 29243837 DOI: 10.1002/jobm.201700525] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 11/02/2017] [Accepted: 11/19/2017] [Indexed: 11/11/2022]
Abstract
A new minireplicon (rep26 minireplicon) from pBMB26, the 188 kb indigenous plasmid related to spore-crystal association (SCA) phenotype in Bacillus thuringiensis strain YBT-020, was characterized. A 12 kb EcoRI fragment, which encoded 10 putative open reading frames (ORFs), was capable of supporting replication when cloned in a replication probe vector. Deletion and frame shift mutation analysis showed that a 4.1 kb region encompassing two putative ORFs (orf21 and orf22) was essential for the plasmid replication in B. thuringiensis. Gene orf21 encoding a 49.8 kDa protein (named Rep26) with a helix-turn-helix motif showed no homology with known replication proteins and gene orf22 encoding a protein of 82.6 kDa showed homology to bacterial PcrA helicase. The replication origin of rep26 minireplicon was proved to be located in the coding region of orf21. Plasmid stability experiments indicated that the recombinant plasmid containing rep26 minireplicon has excellent segregational stability. BLASTP analysis revealed that amino acid sequences of ORF21 and ORF22 were well conserved among Bacillus cereus group strains. The rep26 minireplicon was widely distributed and could be defined as a new typical replicon in the megaplasmids of B. cereus group.
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Affiliation(s)
- Pengxia Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, People's Republic of China
| | - Yiguang Zhu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, People's Republic of China
| | - Hui Shang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, People's Republic of China
| | - Yun Deng
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, People's Republic of China
| | - Ming Sun
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, People's Republic of China
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Shchit IY, Ignatov KB, Kudryavtseva TY, Shishkova NA, Mironova RI, Marinin LI, Mokrievich AN, Kramarov VM, Biketov SF, Dyatlov IA. The use of loop-mediated isothermal DNA amplification for the detection and identification of the anthrax pathogen. MOLECULAR GENETICS MICROBIOLOGY AND VIROLOGY 2017; 32:100-108. [PMID: 32214650 PMCID: PMC7088587 DOI: 10.3103/s0891416817020094] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Indexed: 01/16/2023]
Abstract
The results of detection and identification of Bacillus anthracis strains in loop-mediated isothermal DNA amplification (LAMP) reaction performed under optimized conditions with original primers and thermostable DNA polymerase are presented. Reproducible LAMP-based detection of chromosomal and plasmid DNA targets specific for B. anthracis strains has been demonstrated. No cross reactions with DNA from bacterial strains of other species of the B. cereus group were detected. The development of tests for anthrax-pathogen detection based on the optimized reaction of loop isothermal DNA amplification is planned. These tests will be convenient for clinical studies and field diagnostics due to the absence of requirements for sophisticated equipment.
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Affiliation(s)
- I Yu Shchit
- 1State Research Center of Applied Microbiology and Biotechnology, Federal Service for the Protection of Customer Rights, Obolensk, 142279 Russia
| | - K B Ignatov
- 2Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, 117971 Russia.,3All-Russian Research Institute of Agricultural Biotechnology, Russian Academy of Sciences, Moscow, 127422 Russia
| | - T Yu Kudryavtseva
- 1State Research Center of Applied Microbiology and Biotechnology, Federal Service for the Protection of Customer Rights, Obolensk, 142279 Russia
| | - N A Shishkova
- 1State Research Center of Applied Microbiology and Biotechnology, Federal Service for the Protection of Customer Rights, Obolensk, 142279 Russia
| | - R I Mironova
- 1State Research Center of Applied Microbiology and Biotechnology, Federal Service for the Protection of Customer Rights, Obolensk, 142279 Russia
| | - L I Marinin
- 1State Research Center of Applied Microbiology and Biotechnology, Federal Service for the Protection of Customer Rights, Obolensk, 142279 Russia
| | - A N Mokrievich
- 1State Research Center of Applied Microbiology and Biotechnology, Federal Service for the Protection of Customer Rights, Obolensk, 142279 Russia
| | - V M Kramarov
- 2Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, 117971 Russia.,3All-Russian Research Institute of Agricultural Biotechnology, Russian Academy of Sciences, Moscow, 127422 Russia
| | - S F Biketov
- 1State Research Center of Applied Microbiology and Biotechnology, Federal Service for the Protection of Customer Rights, Obolensk, 142279 Russia
| | - I A Dyatlov
- 1State Research Center of Applied Microbiology and Biotechnology, Federal Service for the Protection of Customer Rights, Obolensk, 142279 Russia
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Raymond B, Federici BA. In defense of Bacillus thuringiensis, the safest and most successful microbial insecticide available to humanity - a response to EFSA. FEMS Microbiol Ecol 2017. [PMID: 28645183 PMCID: PMC5812528 DOI: 10.1093/femsec/fix084] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The Bacillus cereus group contains vertebrate pathogens such as B. anthracis and B. cereus and the invertebrate pathogen B. thuringiensis (Bt). Microbial biopesticides based on Bt are widely recognised as being among the safest and least environmentally damaging insecticidal products available. Nevertheless, a recent food-poisoning incident prompted a European Food Safety Authority review which argued that Bt poses a health risk equivalent to B. cereus, a causative agent of diarrhoea. However, a critical examination of available data, and this latest incident, provides no solid evidence that Bt causes diarrhoea. Although relatively high levels of B. cereus-like spores can occur in foods, genotyping demonstrates that these are predominantly naturally occurring strains rather than biopesticides. Moreover, MLST genotyping of >2000 isolates show that biopesticide genotypes have never been isolated from any clinical infection. MLST data demonstrate that B. cereus group is heterogeneous and formed of distinct clades with substantial differences in biology, ecology and host association. The group posing the greatest risk (the anthracis clade) is distantly related to the clade containing all biopesticides. These recent data support the long-held view that Bt and especially the strains used in Bt biopesticides are very safe for humans.
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Affiliation(s)
- Ben Raymond
- University of Exeter, Penryn campus, Penryn, TR10 9FE, UK
| | - Brian A Federici
- Department of Entomology and Institute for Integrative Genome Biology, University of California, Riverside, Riverside, CA 92521 USA
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Evolutionary processes and environmental factors underlying the genetic diversity and lifestyles of Bacillus cereus group bacteria. Res Microbiol 2017; 168:309-318. [DOI: 10.1016/j.resmic.2016.07.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 07/03/2016] [Accepted: 07/05/2016] [Indexed: 11/22/2022]
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Xu Z, Xie J, Liu J, Ji L, Soteyome T, Peters BM, Chen D, Li B, Li L, Shirtliff ME. Whole-genome resequencing of Bacillus cereus and expression of genes functioning in sodium chloride stress. Microb Pathog 2017; 104:248-253. [DOI: 10.1016/j.micpath.2017.01.040] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 01/14/2017] [Accepted: 01/24/2017] [Indexed: 10/24/2022]
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Bacillus thuringiensis: a successful insecticide with new environmental features and tidings. Appl Microbiol Biotechnol 2017; 101:2691-2711. [PMID: 28235989 DOI: 10.1007/s00253-017-8175-y] [Citation(s) in RCA: 116] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Revised: 01/31/2017] [Accepted: 02/02/2017] [Indexed: 12/15/2022]
Abstract
Bacillus thuringiensis (Bt) is known as the most successful microbial insecticide against different orders of insect pests in agriculture and medicine. Moreover, Bt toxin genes also have been efficiently used to enhance resistance to insect pests in genetically modified crops. In light of the scientific advantages of new molecular biology technologies, recently, some other new potentials of Bt have been explored. These new environmental features include the toxicity against nematodes, mites, and ticks, antagonistic effects against plant and animal pathogenic bacteria and fungi, plant growth-promoting activities (PGPR), bioremediation of different heavy metals and other pollutants, biosynthesis of metal nanoparticles, production of polyhydroxyalkanoate biopolymer, and anticancer activities (due to parasporins). This review comprehensively describes recent advances in the Bt whole-genome studies, the last updated known Bt toxins and their functions, and application of cry genes in plant genetic engineering. Moreover, the review thoroughly describes the new features of Bt which make it a suitable cell factory that might be used for production of different novel valuable bioproducts.
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Hollensteiner J, Wemheuer F, Harting R, Kolarzyk AM, Diaz Valerio SM, Poehlein A, Brzuszkiewicz EB, Nesemann K, Braus-Stromeyer SA, Braus GH, Daniel R, Liesegang H. Bacillus thuringiensis and Bacillus weihenstephanensis Inhibit the Growth of Phytopathogenic Verticillium Species. Front Microbiol 2017; 7:2171. [PMID: 28149292 PMCID: PMC5241308 DOI: 10.3389/fmicb.2016.02171] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 12/23/2016] [Indexed: 12/14/2022] Open
Abstract
Verticillium wilt causes severe yield losses in a broad range of economically important crops worldwide. As many soil fumigants have a severe environmental impact, new biocontrol strategies are needed. Members of the genus Bacillus are known as plant growth-promoting bacteria (PGPB) as well as biocontrol agents of pests and diseases. In this study, we isolated 267 Bacillus strains from root-associated soil of field-grown tomato plants. We evaluated the antifungal potential of 20 phenotypically diverse strains according to their antagonistic activity against the two phytopathogenic fungi Verticillium dahliae and Verticillium longisporum. In addition, the 20 strains were sequenced and phylogenetically characterized by multi-locus sequence typing (MLST) resulting in 7 different Bacillus thuringiensis and 13 Bacillus weihenstephanensis strains. All B. thuringiensis isolates inhibited in vitro the tomato pathogen V. dahliae JR2, but had only low efficacy against the tomato-foreign pathogen V. longisporum 43. All B. weihenstephanensis isolates exhibited no fungicidal activity whereas three B. weihenstephanensis isolates showed antagonistic effects on both phytopathogens. These strains had a rhizoid colony morphology, which has not been described for B. weihenstephanensis strains previously. Genome analysis of all isolates revealed putative genes encoding fungicidal substances and resulted in identification of 304 secondary metabolite gene clusters including 101 non-ribosomal polypeptide synthetases and 203 ribosomal-synthesized and post-translationally modified peptides. All genomes encoded genes for the synthesis of the antifungal siderophore bacillibactin. In the genome of one B. thuringiensis strain, a gene cluster for zwittermicin A was detected. Isolates which either exhibited an inhibitory or an interfering effect on the growth of the phytopathogens carried one or two genes encoding putative mycolitic chitinases, which might contribute to antifungal activities. This indicates that chitinases contribute to antifungal activities. The present study identified B. thuringiensis isolates from tomato roots which exhibited in vitro antifungal activity against Verticillium species.
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Affiliation(s)
- Jacqueline Hollensteiner
- Göttingen Genomics Laboratory, Department of Genomic and Applied Microbiology, Institute of Microbiology and Genetics, Georg-August-University Gottingen, Germany
| | - Franziska Wemheuer
- Göttingen Genomics Laboratory, Department of Genomic and Applied Microbiology, Institute of Microbiology and Genetics, Georg-August-University Gottingen, Germany
| | - Rebekka Harting
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics and Göttingen Center for Molecular Biosciences, Georg-August-University Gottingen, Germany
| | - Anna M Kolarzyk
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics and Göttingen Center for Molecular Biosciences, Georg-August-University Gottingen, Germany
| | - Stefani M Diaz Valerio
- Göttingen Genomics Laboratory, Department of Genomic and Applied Microbiology, Institute of Microbiology and Genetics, Georg-August-University Gottingen, Germany
| | - Anja Poehlein
- Göttingen Genomics Laboratory, Department of Genomic and Applied Microbiology, Institute of Microbiology and Genetics, Georg-August-University Gottingen, Germany
| | - Elzbieta B Brzuszkiewicz
- Göttingen Genomics Laboratory, Department of Genomic and Applied Microbiology, Institute of Microbiology and Genetics, Georg-August-University Gottingen, Germany
| | - Kai Nesemann
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics and Göttingen Center for Molecular Biosciences, Georg-August-University Gottingen, Germany
| | - Susanna A Braus-Stromeyer
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics and Göttingen Center for Molecular Biosciences, Georg-August-University Gottingen, Germany
| | - Gerhard H Braus
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics and Göttingen Center for Molecular Biosciences, Georg-August-University Gottingen, Germany
| | - Rolf Daniel
- Göttingen Genomics Laboratory, Department of Genomic and Applied Microbiology, Institute of Microbiology and Genetics, Georg-August-University Gottingen, Germany
| | - Heiko Liesegang
- Göttingen Genomics Laboratory, Department of Genomic and Applied Microbiology, Institute of Microbiology and Genetics, Georg-August-University Gottingen, Germany
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Li F, Zuo S, Yu P, Zhou B, Wang L, Liu C, Wei H, Hengyi Xu. Distribution and expression of the enterotoxin genes of Bacillus cereus in food products from Jiangxi Province, China. Food Control 2016. [DOI: 10.1016/j.foodcont.2016.02.049] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Abstract
Bacillus cereus UW85 was isolated from a root of a field-grown alfalfa plant from Arlington, WI, and identified for its ability to suppress damping off, a disease caused by Phytophthora megasperma f. sp. medicaginis on alfalfa. Here, we report the draft genome sequence of B. cereus UW85, obtained by a combination of Sanger and Illumina sequencing.
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Peng Q, Liu C, Wang B, Yang M, Wu J, Zhang J, Song F. Sox transcription in sarcosine utilization is controlled by Sigma(54) and SoxR in Bacillus thuringiensis HD73. Sci Rep 2016; 6:29141. [PMID: 27404799 PMCID: PMC4941409 DOI: 10.1038/srep29141] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 06/10/2016] [Indexed: 12/04/2022] Open
Abstract
Sarcosine oxidase catalyzes the oxidative demethylation of sarcosine to yield glycine, formaldehyde, and hydrogen peroxide. In this study, we analyzed the transcription and regulation of the sox locus, including the sarcosine oxidase-encoding genes in Bacillus thuringiensis (Bt). RT-PCR analysis revealed that the sox locus forms two opposing transcriptional units: soxB (soxB/E/F/G/H/I) and soxR (soxR/C/D/A). The typical −12/−24 consensus sequence was located 15 bp and 12 bp from the transcriptional start site (TSS) of soxB and soxC, respectively. Promoter-lacZ fusion assays showed that the soxB promoter is controlled by the Sigma54 factor and is activated by the Sigma54-dependent transcriptional regulator SoxR. SoxR also inhibits its own expression. Expression from the PsoxCR promoter, which is responsible for the transcription of soxC, soxD, and soxA, is Sigma54-dependent and requires SoxR. An 11-bp inverted repeat sequence was identified as SoxR binding site upstream of the soxB TSS. Purified SoxR specifically bound a DNA fragment containing this region. Mutation or deletion of this sequence abolished the transcriptional activities of soxB and soxC. Thus, SoxR binds to the same sequence to activate the transcription of soxB and soxC. Sarcosine utilization was abolished in soxB and soxR mutants, suggesting that the sox locus is essential for sarcosine utilization.
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Affiliation(s)
- Qi Peng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Chunxia Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Bo Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.,College of Life Sciences, Northeast Agriculture University, Harbin, China
| | - Min Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jianbo Wu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jie Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Fuping Song
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
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Whole-Genome Sequences of Seven Strains of Bacillus cereus Isolated from Foodstuff or Poisoning Incidents. GENOME ANNOUNCEMENTS 2016; 4:4/3/e00435-16. [PMID: 27284145 PMCID: PMC4901214 DOI: 10.1128/genomea.00435-16] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We present here the whole shotgun genome sequences of seven strains of Bacillus cereus isolated from foodstuff samples or food poisoning incidents.
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32
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Quan M, Xie J, Liu X, Li Y, Rang J, Zhang T, Zhou F, Xia L, Hu S, Sun Y, Ding X. Comparative Analysis of Genomics and Proteomics in the New Isolated Bacillus thuringiensis X022 Revealed the Metabolic Regulation Mechanism of Carbon Flux Following Cu(2+) Treatment. Front Microbiol 2016; 7:792. [PMID: 27303381 PMCID: PMC4882340 DOI: 10.3389/fmicb.2016.00792] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Accepted: 05/09/2016] [Indexed: 01/23/2023] Open
Abstract
Bacillus thuringiensis (Bt) X022 is a novel strain isolated from soil in China, and showed strong insecticidal activity against several Lepidopteran pests. In this work, we performed whole genome sequencing of this Bt strain using the next-generation sequencing technology, and further conducted a comparative analysis with the proteomics data of the specific spore-release period based on LC-MS/MS approach. The Bt X022 genome consisted of one circular chromosomal DNA and seven plasmids, which were further functionally annotated using the RAST server. Comparative analysis of insecticidal substances showed that X022 contained genes coding for three Cry proteins (Cry1Ac, Cry1Ia and Cry2Ab) and a vegetative insecticidal protein (Vip3A). However, three insecticidal crystal proteins (ICPs) (Cry1Ca, Cry1Ac and Cry1Da) were detected by proteomics in the spore-release period. Moreover, a putative biosynthetic gene cluster and the metabolic pathway for poly-β-hydroxybutyrate in Bt X022 were deduced based on the comparative analysis of genomic and proteomic data, which revealed the metabolic regulation mechanism of carbon flux correlated with increased production of ICPs caused by Cu2+. Hence, these results provided a deeper understanding of the genetic background and protein expression profile of Bt X022. This study established a foundation for directed genetic modification and further application of this new isolated Bt strain.
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Affiliation(s)
- Meifang Quan
- Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, College of Life Science, Hunan Normal UniversityChangsha, China; Laboratory of Medicine Engineering, College of Medicine, Hunan Normal UniversityChangsha, China
| | - Junyan Xie
- Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, College of Life Science, Hunan Normal University Changsha, China
| | - Xuemei Liu
- Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, College of Life Science, Hunan Normal University Changsha, China
| | - Yang Li
- Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, College of Life Science, Hunan Normal University Changsha, China
| | - Jie Rang
- Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, College of Life Science, Hunan Normal University Changsha, China
| | - Tong Zhang
- Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, College of Life Science, Hunan Normal University Changsha, China
| | - Fengjuan Zhou
- Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, College of Life Science, Hunan Normal University Changsha, China
| | - Liqiu Xia
- Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, College of Life Science, Hunan Normal University Changsha, China
| | - Shengbiao Hu
- Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, College of Life Science, Hunan Normal University Changsha, China
| | - Yunjun Sun
- Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, College of Life Science, Hunan Normal University Changsha, China
| | - Xuezhi Ding
- Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, College of Life Science, Hunan Normal University Changsha, China
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Lee JY, Kinch LN, Borek DM, Wang J, Wang J, Urbatsch IL, Xie XS, Grishin NV, Cohen JC, Otwinowski Z, Hobbs HH, Rosenbaum DM. Crystal structure of the human sterol transporter ABCG5/ABCG8. Nature 2016; 533:561-4. [PMID: 27144356 PMCID: PMC4964963 DOI: 10.1038/nature17666] [Citation(s) in RCA: 201] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 03/15/2016] [Indexed: 02/08/2023]
Abstract
ATP binding cassette (ABC) transporters play critical roles in maintaining sterol balance in higher eukaryotes. The ABCG5/ABCG8 heterodimer (G5G8) mediates excretion of neutral sterols in liver and intestines. Mutations disrupting G5G8 cause sitosterolaemia, a disorder characterized by sterol accumulation and premature atherosclerosis. Here we use crystallization in lipid bilayers to determine the X-ray structure of human G5G8 in a nucleotide-free state at 3.9 Å resolution, generating the first atomic model of an ABC sterol transporter. The structure reveals a new transmembrane fold that is present in a large and functionally diverse superfamily of ABC transporters. The transmembrane domains are coupled to the nucleotide-binding sites by networks of interactions that differ between the active and inactive ATPases, reflecting the catalytic asymmetry of the transporter. The G5G8 structure provides a mechanistic framework for understanding sterol transport and the disruptive effects of mutations causing sitosterolaemia.
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Affiliation(s)
- Jyh-Yeuan Lee
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, USA
| | - Lisa N Kinch
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Dominika M Borek
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Jin Wang
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, USA
| | - Junmei Wang
- Cecil &Ida Green Center for Molecular, Computational and Systems Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Ina L Urbatsch
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA
| | - Xiao-Song Xie
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, USA
| | - Nikolai V Grishin
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Jonathan C Cohen
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, USA
| | - Zbyszek Otwinowski
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Helen H Hobbs
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, USA
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Daniel M Rosenbaum
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
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Transcriptome analysis of Bacillus thuringiensis spore life, germination and cell outgrowth in a vegetable-based food model. Food Microbiol 2016; 55:73-85. [DOI: 10.1016/j.fm.2015.11.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 11/03/2015] [Accepted: 11/10/2015] [Indexed: 11/19/2022]
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35
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The Regulation of Exosporium-Related Genes in Bacillus thuringiensis. Sci Rep 2016; 6:19005. [PMID: 26805020 PMCID: PMC4750369 DOI: 10.1038/srep19005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 12/02/2015] [Indexed: 11/09/2022] Open
Abstract
Bacillus anthracis, Bacillus cereus, and Bacillus thuringiensis (Bt) are spore-forming members of the Bacillus cereus group. Spores of B. cereus group species are encircled by exosporium, which is composed of an external hair-like nap and a paracrystalline basal layer. Despite the extensive studies on the structure of the exosporium-related proteins, little is known about the transcription and regulation of exosporium gene expression in the B. cereus group. Herein, we studied the regulation of several exosporium-related genes in Bt. A SigK consensus sequence is present upstream of genes encoding hair-like nap proteins (bclA and bclB), basal layer proteins (bxpA, bxpB, cotB, and exsY ), and inosine hydrolase (iunH). Mutation of sigK decreased the transcriptional activities of all these genes, indicating that the transcription of these genes is controlled by SigK. Furthermore, mutation of gerE decreased the transcriptional activities of bclB, bxpB, cotB, and iunH but increased the expression of bxpA, and GerE binds to the promoters of bclB, bxpB, cotB, bxpA, and iunH. These results suggest that GerE directly regulates the transcription of these genes, increasing the expression of bclB, bxpB, cotB, and iunH and decreasing that of bxpA. These findings provide insight into the exosporium assembly process at the transcriptional level.
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Freas N, Newton P, Perozich J. Analysis of nucleotide diphosphate sugar dehydrogenases reveals family and group-specific relationships. FEBS Open Bio 2016; 6:77-89. [PMID: 27047744 PMCID: PMC4794789 DOI: 10.1002/2211-5463.12022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 12/03/2015] [Accepted: 12/14/2015] [Indexed: 12/02/2022] Open
Abstract
UDP‐glucose dehydrogenase (UDPGDH), UDP‐N‐acetyl‐mannosamine dehydrogenase (UDPNAMDH) and GDP‐mannose dehydrogenase (GDPMDH) belong to a family of NAD+‐linked 4‐electron‐transfering oxidoreductases called nucleotide diphosphate sugar dehydrogenases (NDP‐SDHs). UDPGDH is an enzyme responsible for converting UDP‐d‐glucose to UDP‐d‐glucuronic acid, a product that has different roles depending on the organism in which it is found. UDPNAMDH and GDPMDH convert UDP‐N‐acetyl‐mannosamine to UDP‐N‐acetyl‐mannosaminuronic acid and GDP‐mannose to GDP‐mannuronic acid, respectively, by a similar mechanism to UDPGDH. Their products are used as essential building blocks for the exopolysaccharides found in organisms like Pseudomonas aeruginosa and Staphylococcus aureus. Few studies have investigated the relationships between these enzymes. This study reveals the relationships between the three enzymes by analysing 229 amino acid sequences. Eighteen invariant and several other highly conserved residues were identified, each serving critical roles in maintaining enzyme structure, coenzyme binding or catalytic function. Also, 10 conserved motifs that included most of the conserved residues were identified and their roles proposed. A phylogenetic tree demonstrated relationships between each group and verified group assignment. Finally, group entropy analysis identified novel conservations unique to each NDP‐SDH group, including residue positions critical to NDP‐sugar substrate interaction, enzyme structure and intersubunit contact. These positions may serve as targets for future research. Enzymes UDP‐glucose dehydrogenase (UDPGDH, EC 1.1.1.22).
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Affiliation(s)
- Nicholas Freas
- Department of Biology Franciscan University of Steubenville OH USA
| | - Peter Newton
- Department of Biology Franciscan University of Steubenville OH USA
| | - John Perozich
- Department of Biology Franciscan University of Steubenville OH USA
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Remigi P, Zhu J, Young JPW, Masson-Boivin C. Symbiosis within Symbiosis: Evolving Nitrogen-Fixing Legume Symbionts. Trends Microbiol 2015; 24:63-75. [PMID: 26612499 DOI: 10.1016/j.tim.2015.10.007] [Citation(s) in RCA: 143] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 10/08/2015] [Accepted: 10/22/2015] [Indexed: 10/22/2022]
Abstract
Bacterial accessory genes are genomic symbionts with an evolutionary history and future that is different from that of their hosts. Packages of accessory genes move from strain to strain and confer important adaptations, such as interaction with eukaryotes. The ability to fix nitrogen with legumes is a remarkable example of a complex trait spread by horizontal transfer of a few key symbiotic genes, converting soil bacteria into legume symbionts. Rhizobia belong to hundreds of species restricted to a dozen genera of the Alphaproteobacteria and Betaproteobacteria, suggesting infrequent successful transfer between genera but frequent successful transfer within genera. Here we review the genetic and environmental conditions and selective forces that have shaped evolution of this complex symbiotic trait.
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Affiliation(s)
- Philippe Remigi
- INRA, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR441, Castanet-Tolosan, France; CNRS, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR2594, Castanet-Tolosan, France; New Zealand Institute for Advanced Study, Massey University, Auckland, New Zealand
| | - Jun Zhu
- Department of Microbiology, Nanjing Agricultural University, Nanjing, China; Department of Microbiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - J Peter W Young
- Department of Biology, University of York, York YO10 5DD, UK
| | - Catherine Masson-Boivin
- INRA, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR441, Castanet-Tolosan, France; CNRS, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR2594, Castanet-Tolosan, France.
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Lee DH, Kim HR, Chung HY, Lim JG, Kim S, Kim SK, Ku HJ, Kim H, Ryu S, Choi SH, Lee JH. Complete genome sequence of Bacillus cereus FORC_005, a food-borne pathogen from the soy sauce braised fish-cake with quail-egg. Stand Genomic Sci 2015; 10:97. [PMID: 26566422 PMCID: PMC4642778 DOI: 10.1186/s40793-015-0094-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 10/31/2015] [Indexed: 11/10/2022] Open
Abstract
Due to abundant contamination in various foods, the pathogenesis of Bacillus cereus has been widely studied in physiological and molecular level. B. cereus FORC_005 was isolated from a Korean side dish, soy sauce braised fish-cake with quail-egg in South Korea. While 21 complete genome sequences of B. cereus has been announced to date, this strain was completely sequenced, analyzed, and compared with other complete genome sequences of B. cereus to elucidate the distinct pathogenic features of a strain isolated in South Korea. The genomic DNA containing a circular chromosome consists of 5,349,617-bp with a GC content of 35.29 %. It was predicted to have 5170 open reading frames, 106 tRNA genes, and 42 rRNA genes. Among the predicted ORFs, 3892 ORFs were annotated to encode functional proteins (75.28 %) and 1278 ORFs were predicted to encode hypothetical proteins (748 conserved and 530 non-conserved hypothetical proteins). This genome information of B. cereus FORC_005 would extend our understanding of its pathogenesis in genomic level for efficient control of its contamination in foods and further food poisoning.
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Affiliation(s)
- Dong-Hoon Lee
- Department of Food Science and Biotechnology, Institute of Life Science and Resources, Kyung Hee University, Yongin, Republic of Korea
| | - Hye Rim Kim
- National Research Laboratory of Molecular Microbiology and Toxicology, Department of Agricultural Biotechnology, and Center for Food Safety and Toxicology, Seoul National University, Seoul, Republic of Korea
| | - Han Young Chung
- National Research Laboratory of Molecular Microbiology and Toxicology, Department of Agricultural Biotechnology, and Center for Food Safety and Toxicology, Seoul National University, Seoul, Republic of Korea
| | - Jong Gyu Lim
- National Research Laboratory of Molecular Microbiology and Toxicology, Department of Agricultural Biotechnology, and Center for Food Safety and Toxicology, Seoul National University, Seoul, Republic of Korea
| | - Suyeon Kim
- National Research Laboratory of Molecular Microbiology and Toxicology, Department of Agricultural Biotechnology, and Center for Food Safety and Toxicology, Seoul National University, Seoul, Republic of Korea
| | - Se Keun Kim
- National Research Laboratory of Molecular Microbiology and Toxicology, Department of Agricultural Biotechnology, and Center for Food Safety and Toxicology, Seoul National University, Seoul, Republic of Korea
| | - Hye-Jin Ku
- Department of Food Science and Biotechnology, Institute of Life Science and Resources, Kyung Hee University, Yongin, Republic of Korea
| | - Heebal Kim
- Department of Agricultural Biotechnology, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea
| | - Sangryeol Ryu
- Department of Food and Animal Biotechnology, Department of Agricultural Biotechnology, Research Institute of Agriculture and Life Sciences, and Center for Food and Bioconvergence, Seoul National University, Seoul, Republic of Korea
| | - Sang Ho Choi
- National Research Laboratory of Molecular Microbiology and Toxicology, Department of Agricultural Biotechnology, and Center for Food Safety and Toxicology, Seoul National University, Seoul, Republic of Korea
| | - Ju-Hoon Lee
- Department of Food Science and Biotechnology, Institute of Life Science and Resources, Kyung Hee University, Yongin, Republic of Korea
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Massive horizontal gene transfer, strictly vertical inheritance and ancient duplications differentially shape the evolution of Bacillus cereus enterotoxin operons hbl, cytK and nhe. BMC Evol Biol 2015; 15:246. [PMID: 26555390 PMCID: PMC4641410 DOI: 10.1186/s12862-015-0529-4] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 10/30/2015] [Indexed: 11/10/2022] Open
Abstract
Background Bacillus cereus sensu lato comprises eight closely related species including the human pathogens Bacillus anthracis and Bacillus cereus. Within B. cereus sensu lato, chromosomally and plasmid-encoded toxins exist. While plasmid-mediated horizontal gene transfer of the emetic toxin, anthrax and insecticidal toxins is known, evolution of enterotoxin genes within the group has not been studied. Results We report draft genome assemblies of 25 strains, a phylogenetic network of 142 strains based on ANI derived from genome sequences and a phylogeny based on whole-genome SNP analysis. The data clearly support subdivision of B. cereus sensu lato into seven phylogenetic groups. While group I, V and VII represent B. pseudomycoides, B. toyonensis and B. cytotoxicus, which are distinguishable at species level (ANI border ≥ 96 %), strains ascribed to the other five species do not match phylogenic groups. The chromosomal enterotoxin operons nheABC and hblCDAB are abundant within B. cereus both isolated from infections and from the environment. While the duplicated hbl variant hbla is present in 22 % of all strains investigated, duplication of nheABC is extremely rare (0.02 %) and appears to be phylogenetically unstable. Distribution of toxin genes was matched to a master tree based on seven concatenated housekeeping genes, which depicts species relationships in B. cereus sensu lato as accurately as whole-genome comparisons. Comparison to the phylogeny of enterotoxin genes uncovered ample evidence for horizontal transfer of hbl, cytK and plcR, as well as frequent deletion of both toxins and duplication of hbl. No evidence for nhe deletion was found and stable horizontal transfer of nhe is rare. Therefore, evolution of B. cereus enterotoxin operons is shaped unexpectedly different for yet unknown reasons. Conclusions Frequent exchange of the pathogenicity factors hbl, cytK and plcR in B. cereus sensu lato appears to be an important mechanism of B. cereus virulence evolution, including so-called probiotic or non-pathogenic species, which might have consequences for risk assessment procedures. In contrast, exclusively vertical inheritance of nhe was observed, and since nhe-negative strains appear to be extremely rare, we suggest that fitness loss may be associated with deletion or horizontal transfer of the nhe operon. Electronic supplementary material The online version of this article (doi:10.1186/s12862-015-0529-4) contains supplementary material, which is available to authorized users.
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Genomic and transcriptomic insights into the efficient entomopathogenicity of Bacillus thuringiensis. Sci Rep 2015; 5:14129. [PMID: 26411888 PMCID: PMC4585936 DOI: 10.1038/srep14129] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 07/31/2015] [Indexed: 11/19/2022] Open
Abstract
Bacillus thuringiensis has been globally used as a microbial pesticide for over 70 years. However, information regarding its various adaptions and virulence factors and their roles in the entomopathogenic process remains limited. In this work, we present the complete genomes of two industrially patented Bacillus thuringiensis strains (HD-1 and YBT-1520). A comparative genomic analysis showed a larger and more complicated genome constitution that included novel insecticidal toxicity-related genes (ITRGs). All of the putative ITRGs were summarized according to the steps of infection. A comparative genomic analysis showed that highly toxic strains contained significantly more ITRGs, thereby providing additional strategies for infection, immune evasion, and cadaver utilization. Furthermore, a comparative transcriptomic analysis suggested that a high expression of these ITRGs was a key factor in efficient entomopathogenicity. We identified an active extra urease synthesis system in the highly toxic strains that may aid B. thuringiensis survival in insects (similar to previous results with well-known pathogens). Taken together, these results explain the efficient entomopathogenicity of B. thuringiensis. It provides novel insights into the strategies used by B. thuringiensis to resist and overcome host immune defenses and helps identify novel toxicity factors.
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Kumar N, Lad G, Giuntini E, Kaye ME, Udomwong P, Shamsani NJ, Young JPW, Bailly X. Bacterial genospecies that are not ecologically coherent: population genomics of Rhizobium leguminosarum. Open Biol 2015; 5:140133. [PMID: 25589577 PMCID: PMC4313370 DOI: 10.1098/rsob.140133] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Biological species may remain distinct because of genetic isolation or ecological adaptation, but these two aspects do not always coincide. To establish the nature of the species boundary within a local bacterial population, we characterized a sympatric population of the bacterium Rhizobium leguminosarum by genomic sequencing of 72 isolates. Although all strains have 16S rRNA typical of R. leguminosarum, they fall into five genospecies by the criterion of average nucleotide identity (ANI). Many genes, on plasmids as well as the chromosome, support this division: recombination of core genes has been largely within genospecies. Nevertheless, variation in ecological properties, including symbiotic host range and carbon-source utilization, cuts across these genospecies, so that none of these phenotypes is diagnostic of genospecies. This phenotypic variation is conferred by mobile genes. The genospecies meet the Mayr criteria for biological species in respect of their core genes, but do not correspond to coherent ecological groups, so periodic selection may not be effective in purging variation within them. The population structure is incompatible with traditional ‘polyphasic taxonomy′ that requires bacterial species to have both phylogenetic coherence and distinctive phenotypes. More generally, genomics has revealed that many bacterial species share adaptive modules by horizontal gene transfer, and we envisage a more consistent taxonomic framework that explicitly recognizes this. Significant phenotypes should be recognized as ‘biovars' within species that are defined by core gene phylogeny.
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Affiliation(s)
- Nitin Kumar
- Department of Biology, University of York, York YO10 5DD, UK
| | - Ganesh Lad
- Department of Biology, University of York, York YO10 5DD, UK
| | - Elisa Giuntini
- Department of Biology, University of York, York YO10 5DD, UK
| | - Maria E Kaye
- Department of Biology, University of York, York YO10 5DD, UK
| | | | | | - J Peter W Young
- Department of Biology, University of York, York YO10 5DD, UK
| | - Xavier Bailly
- Department of Biology, University of York, York YO10 5DD, UK
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Varghese NJ, Mukherjee S, Ivanova N, Konstantinidis KT, Mavrommatis K, Kyrpides NC, Pati A. Microbial species delineation using whole genome sequences. Nucleic Acids Res 2015; 43:6761-71. [PMID: 26150420 PMCID: PMC4538840 DOI: 10.1093/nar/gkv657] [Citation(s) in RCA: 444] [Impact Index Per Article: 49.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 06/12/2015] [Indexed: 01/25/2023] Open
Abstract
Increased sequencing of microbial genomes has revealed that prevailing prokaryotic species assignments can be inconsistent with whole genome information for a significant number of species. The long-standing need for a systematic and scalable species assignment technique can be met by the genome-wide Average Nucleotide Identity (gANI) metric, which is widely acknowledged as a robust measure of genomic relatedness. In this work, we demonstrate that the combination of gANI and the alignment fraction (AF) between two genomes accurately reflects their genomic relatedness. We introduce an efficient implementation of AF,gANI and discuss its successful application to 86.5M genome pairs between 13,151 prokaryotic genomes assigned to 3032 species. Subsequently, by comparing the genome clusters obtained from complete linkage clustering of these pairs to existing taxonomy, we observed that nearly 18% of all prokaryotic species suffer from anomalies in species definition. Our results can be used to explore central questions such as whether microorganisms form a continuum of genetic diversity or distinct species represented by distinct genetic signatures. We propose that this precise and objective AF,gANI-based species definition: the MiSI (Microbial Species Identifier) method, be used to address previous inconsistencies in species classification and as the primary guide for new taxonomic species assignment, supplemented by the traditional polyphasic approach, as required.
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Affiliation(s)
- Neha J Varghese
- Microbial and Metagenome Superprogram, DOE Joint Genomic Institute, Walnut Creek, CA 94598, USA
| | - Supratim Mukherjee
- Microbial and Metagenome Superprogram, DOE Joint Genomic Institute, Walnut Creek, CA 94598, USA
| | - Natalia Ivanova
- Microbial and Metagenome Superprogram, DOE Joint Genomic Institute, Walnut Creek, CA 94598, USA
| | | | | | - Nikos C Kyrpides
- Microbial and Metagenome Superprogram, DOE Joint Genomic Institute, Walnut Creek, CA 94598, USA
| | - Amrita Pati
- Microbial and Metagenome Superprogram, DOE Joint Genomic Institute, Walnut Creek, CA 94598, USA
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Castiaux V, Liu X, Delbrassinne L, Mahillon J. Is Cytotoxin K from Bacillus cereus a bona fide enterotoxin? Int J Food Microbiol 2015; 211:79-85. [PMID: 26186121 DOI: 10.1016/j.ijfoodmicro.2015.06.020] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 06/20/2015] [Accepted: 06/22/2015] [Indexed: 11/19/2022]
Abstract
Cytotoxin K (CytK) produced by Bacillus cereus s.l. has generally been considered to be associated with the foodborne diarrhoeal syndrome. Two distinct variants of CytK have been reported: CytK-1 from Bacillus cytotoxicus and CytK-2 from B. cereus. In order to determine whether CytK plays a significant role in the diarrhoeal disease, the occurrence of cytK genes was assessed among 390 B. cereus isolates with different origins including clinical and food poisoning samples and was found to be 46%. Interestingly, the cytK occurrence was slightly lower in food poisoning and clinical isolates than in environmental samples. Seventy cytK-2 positive strains (including 28 isolates from foodborne outbreaks) were then selected in order to assess their genetic diversity. A genetic dendrogram based on the cytK-2 sequences of these 70 strains and on two cytK-1 sequences from strains NVH 391-98 and 883-00 showed an important diversity. However, no strain clustering according to the origin or source of isolation was observed. These observations were confirmed by Multi-Locus Sequences Typing (MLST) based on five different loci of housekeeping genes (ccpA, recF, sucC, purF and gdpD) for which no grouping of foodborne outbreak strains could be identified. Therefore, the choice of cytK as virulence factor for the diarrhoeal pathotype does not seem to be relevant per se, even though the involvement of CytK in the diarrhoeal syndrome cannot be fully excluded. Potential synergistic effects between CytK and other virulence factors, together with their potential variable expression levels should be further investigated.
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Affiliation(s)
- Virginie Castiaux
- Laboratory of Food and Environmental Microbiology, Université catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium
| | - Xiaojin Liu
- Laboratory of Food and Environmental Microbiology, Université catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium
| | - Laurence Delbrassinne
- Laboratory of Food and Environmental Microbiology, Université catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium; Scientific Institute of Public Health, Juliette Wytsman street 14, B-1050 Brussels, Belgium
| | - Jacques Mahillon
- Laboratory of Food and Environmental Microbiology, Université catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium.
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Peng Q, Wang G, Liu G, Zhang J, Song F. Identification of metabolism pathways directly regulated by sigma(54) factor in Bacillus thuringiensis. Front Microbiol 2015; 6:407. [PMID: 26029175 PMCID: PMC4428206 DOI: 10.3389/fmicb.2015.00407] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Accepted: 04/19/2015] [Indexed: 11/13/2022] Open
Abstract
Sigma(54) (σ(54)) regulates nitrogen and carbon utilization in bacteria. Promoters that are σ(54)-dependent are highly conserved and contain short sequences located at the -24 and -12 positions upstream of the transcription initiation site. σ(54) requires regulatory proteins known as bacterial enhancer-binding proteins (bEBPs) to activate gene transcription. We show that σ(54) regulates the capacity to grow on various nitrogen sources using a Bacillus thuringiensis HD73 mutant lacking the sigL gene encoding σ(54) (ΔsigL). A 2-fold-change cutoff and a false discovery rate cutoff of P < 0.05 were used to analyze the DNA microarray data, which revealed 255 genes that were downregulated and 121 that were upregulated in the ΔsigL mutant relative to the wild-type HD73 strain. The σ(54) regulon (stationary phase) was characterized by DNA microarray, bioinformatics, and functional assay; 16 operons containing 47 genes were identified whose promoter regions contain the conserved -12/-24 element and whose transcriptional activities were abolished or reduced in the ΔsigL mutant. Eight σ(54)-dependent transcriptional bEBPs were found in the Bt HD73 genome, and they regulated nine σ(54)-dependent promoters. The metabolic pathways activated by σ(54) in this process have yet to be identified in Bacillus thuringiensis; nonetheless, the present analysis of the σ(54) regulon provides a better understanding of the physiological roles of σ factors in bacteria.
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Affiliation(s)
- Qi Peng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences Beijing, China
| | - Guannan Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences Beijing, China
| | - Guiming Liu
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences Beijing, China
| | - Jie Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences Beijing, China
| | - Fuping Song
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences Beijing, China
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Ogawa H, Ohnuma M, Squarre D, Mweene AS, Ezaki T, Fujikura D, Ohnishi N, Thomas Y, Hang'ombe BM, Higashi H. Bacillus cereus from the environment is genetically related to the highly pathogenic B. cereus in Zambia. J Vet Med Sci 2015; 77:993-5. [PMID: 25797134 PMCID: PMC4565826 DOI: 10.1292/jvms.15-0059] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
To follow-up anthrax in Zambia since the outbreak in 2011, we have collected samples from the environment and the carcasses of anthrax-suspected animals, and have tried to isolate Bacillus anthracis. In the process of identification of B. anthracis, we collected two isolates, of which colonies were similar to B. anthracis; however, from the results of identification using the molecular-based methods, two isolates were genetically related to the highly pathogenic B. cereus, of which clinical manifestation is severe and fatal (e.g., pneumonia). In this study, we showed the existence of bacteria suspected to be highly pathogenic B. cereus in Zambia, indicating the possibility of an outbreak caused by highly pathogenic B. cereus.
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Affiliation(s)
- Hirohito Ogawa
- Hokudai Center for Zoonosis Control in Zambia, School of Veterinary Medicine, University of Zambia, P.O. Box 32379, Lusaka 10101, Zambia
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46
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Rang J, He H, Wang T, Ding X, Zuo M, Quan M, Sun Y, Yu Z, Hu S, Xia L. Comparative analysis of genomics and proteomics in Bacillus thuringiensis 4.0718. PLoS One 2015; 10:e0119065. [PMID: 25781161 PMCID: PMC4363619 DOI: 10.1371/journal.pone.0119065] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 01/09/2015] [Indexed: 11/18/2022] Open
Abstract
Bacillus thuringiensis is a widely used biopesticide that produced various insecticidal active substances during its life cycle. Separation and purification of numerous insecticide active substances have been difficult because of the relatively short half-life of such substances. On the other hand, substances can be synthetized at different times during development, so samples at different stages have to be studied, further complicating the analysis. A dual genomic and proteomic approach would enhance our ability to identify such substances, and particularily using mass spectrometry-based proteomic methods. The comparative analysis for genomic and proteomic data have showed that not all of the products deduced from the annotated genome could be identified among the proteomic data. For instance, genome annotation results showed that 39 coding sequences in the whole genome were related to insect pathogenicity, including five cry genes. However, Cry2Ab, Cry1Ia, Cytotoxin K, Bacteriocin, Exoenzyme C3 and Alveolysin could not be detected in the proteomic data obtained. The sporulation-related proteins were also compared analysis, results showed that the great majority sporulation-related proteins can be detected by mass spectrometry. This analysis revealed Spo0A~P, SigF, SigE(+), SigK(+) and SigG(+), all known to play an important role in the process of spore formation regulatory network, also were displayed in the proteomic data. Through the comparison of the two data sets, it was possible to infer that some genes were silenced or were expressed at very low levels. For instance, found that cry2Ab seems to lack a functional promoter while cry1Ia may not be expressed due to the presence of transposons. With this comparative study a relatively complete database can be constructed and used to transform hereditary material, thereby prompting the high expression of toxic proteins. A theoretical basis is provided for constructing highly virulent engineered bacteria and for promoting the application of proteogenomics in the life sciences.
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Affiliation(s)
- Jie Rang
- College of Life Science, Hunan Normal University, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Changsha, China
| | - Hao He
- College of Life Science, Hunan Normal University, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Changsha, China
| | - Ting Wang
- College of Life Science, Hunan Normal University, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Changsha, China
| | - Xuezhi Ding
- College of Life Science, Hunan Normal University, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Changsha, China
- * E-mail: (XZD); (LQX)
| | - Mingxing Zuo
- College of Life Science, Hunan Normal University, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Changsha, China
| | - Meifang Quan
- College of Life Science, Hunan Normal University, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Changsha, China
| | - Yunjun Sun
- College of Life Science, Hunan Normal University, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Changsha, China
| | - Ziquan Yu
- College of Life Science, Hunan Normal University, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Changsha, China
| | - Shengbiao Hu
- College of Life Science, Hunan Normal University, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Changsha, China
| | - Liqiu Xia
- College of Life Science, Hunan Normal University, Hunan Provincial Key Laboratory of Microbial Molecular Biology-State Key Laboratory Breeding Base of Microbial Molecular Biology, Changsha, China
- * E-mail: (XZD); (LQX)
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Ogawa H, Fujikura D, Ohnuma M, Ohnishi N, Hang'ombe BM, Mimuro H, Ezaki T, Mweene AS, Higashi H. A novel multiplex PCR discriminates Bacillus anthracis and its genetically related strains from other Bacillus cereus group species. PLoS One 2015; 10:e0122004. [PMID: 25774512 PMCID: PMC4361551 DOI: 10.1371/journal.pone.0122004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Accepted: 02/09/2015] [Indexed: 11/30/2022] Open
Abstract
Anthrax is an important zoonotic disease worldwide that is caused by Bacillus anthracis, a spore-forming pathogenic bacterium. A rapid and sensitive method to detect B. anthracis is important for anthrax risk management and control in animal cases to address public health issues. However, it has recently become difficult to identify B. anthracis by using previously reported molecular-based methods because of the emergence of B. cereus, which causes severe extra-intestinal infection, as well as the human pathogenic B. thuringiensis, both of which are genetically related to B. anthracis. The close genetic relation of chromosomal backgrounds has led to complexity of molecular-based diagnosis. In this study, we established a B. anthracis multiplex PCR that can screen for the presence of B. anthracis virulent plasmids and differentiate B. anthracis and its genetically related strains from other B. cereus group species. Six sets of primers targeting a chromosome of B. anthracis and B. anthracis-like strains, two virulent plasmids, pXO1 and pXO2, a bacterial gene, 16S rRNA gene, and a mammalian gene, actin-beta gene, were designed. The multiplex PCR detected approximately 3.0 CFU of B. anthracis DNA per PCR reaction and was sensitive to B. anthracis. The internal control primers also detected all bacterial and mammalian DNAs examined, indicating the practical applicability of this assay as it enables monitoring of appropriate amplification. The assay was also applied for detection of clinical strains genetically related to B. anthracis, which were B. cereus strains isolated from outbreaks of hospital infections in Japan, and field strains isolated in Zambia, and the assay differentiated B. anthracis and its genetically related strains from other B. cereus group strains. Taken together, the results indicate that the newly developed multiplex PCR is a sensitive and practical method for detecting B. anthracis.
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Affiliation(s)
- Hirohito Ogawa
- Hokudai Center for Zoonosis Control in Zambia, School of Veterinary Medicine, The University of Zambia, Lusaka, Zambia
- Department of Disease Control, School of Veterinary Medicine, The University of Zambia, Lusaka, Zambia
| | - Daisuke Fujikura
- Division of Infection and Immunity, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Miyuki Ohnuma
- Division of Infection and Immunity, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Naomi Ohnishi
- Division of Infection and Immunity, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Bernard M. Hang'ombe
- Department of Paraclinical Studies, School of Veterinary Medicine, The University of Zambia, Lusaka, Zambia
| | - Hitomi Mimuro
- Division of Bacteriology, Department of Infectious Diseases Control, International Research Center for Infectious Diseases, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- Pathogenic Microbes Repository Unit, International Research Center for Infectious Diseases, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Takayuki Ezaki
- Department of Microbiology, Regeneration and Advanced Medical Science, Gifu University Graduate School of Medicine, Gifu, Japan
| | - Aaron S. Mweene
- Department of Disease Control, School of Veterinary Medicine, The University of Zambia, Lusaka, Zambia
| | - Hideaki Higashi
- Hokudai Center for Zoonosis Control in Zambia, School of Veterinary Medicine, The University of Zambia, Lusaka, Zambia
- Department of Disease Control, School of Veterinary Medicine, The University of Zambia, Lusaka, Zambia
- Division of Infection and Immunity, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
- Global Station for Zoonosis Control, Global Institution for Collaborative Research and Education, Hokkaido University, Sapporo, Japan
- * E-mail:
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48
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Be NA, Thissen JB, Fofanov VY, Allen JE, Rojas M, Golovko G, Fofanov Y, Koshinsky H, Jaing CJ. Metagenomic analysis of the airborne environment in urban spaces. MICROBIAL ECOLOGY 2015; 69:346-55. [PMID: 25351142 PMCID: PMC4312561 DOI: 10.1007/s00248-014-0517-z] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Accepted: 10/09/2014] [Indexed: 05/04/2023]
Abstract
The organisms in aerosol microenvironments, especially densely populated urban areas, are relevant to maintenance of public health and detection of potential epidemic or biothreat agents. To examine aerosolized microorganisms in this environment, we performed sequencing on the material from an urban aerosol surveillance program. Whole metagenome sequencing was applied to DNA extracted from air filters obtained during periods from each of the four seasons. The composition of bacteria, plants, fungi, invertebrates, and viruses demonstrated distinct temporal shifts. Bacillus thuringiensis serovar kurstaki was detected in samples known to be exposed to aerosolized spores, illustrating the potential utility of this approach for identification of intentionally introduced microbial agents. Together, these data demonstrate the temporally dependent metagenomic complexity of urban aerosols and the potential of genomic analytical techniques for biosurveillance and monitoring of threats to public health.
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Affiliation(s)
- Nicholas A. Be
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94551 USA
| | - James B. Thissen
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94551 USA
| | | | - Jonathan E. Allen
- Computation/Global Security Directorates, Lawrence Livermore National Laboratory, Livermore, CA USA
| | - Mark Rojas
- Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX USA
| | - George Golovko
- Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX USA
| | - Yuriy Fofanov
- Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX USA
| | | | - Crystal J. Jaing
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94551 USA
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Jakobs M, Meinhardt F. What renders Bacilli genetically competent? A gaze beyond the model organism. Appl Microbiol Biotechnol 2014; 99:1557-70. [DOI: 10.1007/s00253-014-6316-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 12/08/2014] [Accepted: 12/09/2014] [Indexed: 12/20/2022]
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50
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Thorsen L, Kando CK, Sawadogo H, Larsen N, Diawara B, Ouédraogo GA, Hendriksen NB, Jespersen L. Characteristics and phylogeny of Bacillus cereus strains isolated from Maari, a traditional West African food condiment. Int J Food Microbiol 2014; 196:70-8. [PMID: 25528535 DOI: 10.1016/j.ijfoodmicro.2014.11.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 11/10/2014] [Accepted: 11/24/2014] [Indexed: 10/24/2022]
Abstract
Maari is a spontaneously fermented food condiment made from baobab tree seeds in West African countries. This type of product is considered to be safe, being consumed by millions of people on a daily basis. However, due to the spontaneous nature of the fermentation the human pathogen Bacillus cereus occasionally occurs in Maari. This study characterizes succession patterns and pathogenic potential of B. cereus isolated from the raw materials (ash, water from a drilled well (DW) and potash), seed mash throughout fermentation (0-96h), after steam cooking and sun drying (final product) from two production sites of Maari. Aerobic mesophilic bacterial (AMB) counts in raw materials were of 10(5)cfu/ml in DW, and ranged between 6.5×10(3) and 1.2×10(4)cfu/g in potash, 10(9)-10(10)cfu/g in seed mash during fermentation and 10(7) - 10(9) after sun drying. Fifty three out of total 290 AMB isolates were identified as B. cereus sensu lato by use of ITS-PCR and grouped into 3 groups using PCR fingerprinting based on Escherichia coli phage-M13 primer (M13-PCR). As determined by panC gene sequencing, the isolates of B. cereus belonged to PanC types III and IV with potential for high cytotoxicity. Phylogenetic analysis of concatenated sequences of glpF, gmk, ilvD, pta, pur, pycA and tpi revealed that the M13-PCR group 1 isolates were related to B. cereus biovar anthracis CI, while the M13-PCR group 2 isolates were identical to cereulide (emetic toxin) producing B. cereus strains. The M13-PCR group 1 isolates harboured poly-γ-D-glutamic acid capsule biosynthesis genes capA, capB and capC showing 99-100% identity with the environmental B. cereus isolate 03BB108. Presence of cesB of the cereulide synthetase gene cluster was confirmed by PCR in M13-PCR group 2 isolates. The B. cereus harbouring the cap genes were found in potash, DW, cooking water and at 8h fermentation. The "emetic" type B. cereus were present in DW, the seed mash at 48-72h of fermentation and in the final product, while the remaining isolates (PanC type IV) were detected in ash, at 48-72h fermentation and in the final product. This work sheds light on the succession and pathogenic potential of B. cereus species in traditional West African food condiment and clarifies their phylogenetic relatedness to B. cereus biovar anthracis. Future implementation of GMP and HACCP and development of starter cultures for controlled Maari fermentations will help to ensure a safe product.
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Affiliation(s)
- Line Thorsen
- Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 26, 1958 Frederiksberg C, Denmark
| | - Christine Kere Kando
- Food Technology Department (DTA/IRSAT/CNRST), Ouagadougou 03 BP 7047, Burkina Faso; Université Polytechnique de Bobo-Dioulasso, 01 BP 1091 Bobo-Dioulasso, Burkina Faso
| | - Hagrétou Sawadogo
- Food Technology Department (DTA/IRSAT/CNRST), Ouagadougou 03 BP 7047, Burkina Faso
| | - Nadja Larsen
- Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 26, 1958 Frederiksberg C, Denmark
| | - Bréhima Diawara
- Food Technology Department (DTA/IRSAT/CNRST), Ouagadougou 03 BP 7047, Burkina Faso
| | | | - Niels Bohse Hendriksen
- Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark
| | - Lene Jespersen
- Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 26, 1958 Frederiksberg C, Denmark.
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