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Schäfer L, Volk F, Kleespies RG, Jehle JA, Wennmann JT. Elucidating the genomic history of commercially used Bacillus thuringiensis subsp. tenebrionis strain NB176. Front Cell Infect Microbiol 2023; 13:1129177. [PMID: 37021121 PMCID: PMC10067926 DOI: 10.3389/fcimb.2023.1129177] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 02/17/2023] [Indexed: 04/07/2023] Open
Abstract
Bacillus thuringiensis subsp. tenebrionis (Btt) produces a coleopteran-specific crystal protoxin protein (Cry3Aa δ-endotoxin). After its discovery in 1982, the strain NB125 (DSM 5526) was eventually registered in 1990 to control the Colorado potato beetle (Leptinotarsa decemlineata). Gamma-irradiation of NB125 resulted in strain NB176-1 (DSM 5480) that exhibited higher cry3Aa production and became the active ingredient of the plant protection product Novodor® FC. Here, we report a comparative genome analysis of the parental strain NB125, its derivative NB176-1 and the current commercial production strain NB176. The entire genome sequences of the parental and derivative strains were deciphered by a hybrid de novo approach using short (Illumina) and long (Nanopore) read sequencing techniques. Genome assembly revealed a chromosome of 5.4 to 5.6 Mbp and six plasmids with a size range from 14.9 to 250.5 kbp for each strain. The major differences among the original NB125 and the derivative strains NB176-1 and NB176 were an additional copy of the cry3Aa gene, which translocated to another plasmid as well as a chromosomal deletion (~ 178 kbp) in NB176. The assembled genome sequences were further analyzed in silico for the presence of virulence and antimicrobial resistance (AMR) genes.
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Affiliation(s)
- Lea Schäfer
- Julius Kühn Institute (JKI) - Federal Research Centre for Cultivated Plants, Institute for Biological Control, Dossenheim, Germany
| | | | - Regina G. Kleespies
- Julius Kühn Institute (JKI) - Federal Research Centre for Cultivated Plants, Institute for Biological Control, Dossenheim, Germany
| | - Johannes A. Jehle
- Julius Kühn Institute (JKI) - Federal Research Centre for Cultivated Plants, Institute for Biological Control, Dossenheim, Germany
| | - Jörg T. Wennmann
- Julius Kühn Institute (JKI) - Federal Research Centre for Cultivated Plants, Institute for Biological Control, Dossenheim, Germany
- *Correspondence: Jörg T. Wennmann,
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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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Johler S, Kalbhenn EM, Heini N, Brodmann P, Gautsch S, Bağcioğlu M, Contzen M, Stephan R, Ehling-Schulz M. Enterotoxin Production of Bacillus thuringiensis Isolates From Biopesticides, Foods, and Outbreaks. Front Microbiol 2018; 9:1915. [PMID: 30190709 PMCID: PMC6115515 DOI: 10.3389/fmicb.2018.01915] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 07/30/2018] [Indexed: 11/19/2022] Open
Abstract
While the relevance of Bacillus (B.) cereus as a major cause of gastroenteritis is undisputed, the role of the closely related B. thuringiensis in foodborne disease is unclear. B. thuringiensis strains frequently harbor enterotoxin genes. However, the organism has only very rarely been associated with foodborne outbreaks, possibly due to the fact that during outbreak investigations, B. cereus is routinely not differentiated from B. thuringiensis. A recent EFSA scientific opinion stresses the urgent need for further data allowing for improved risk assessment, in particular as B. thuringiensis is a commonly used biopesticide. Therefore, the aim of this study was to gain further insights into the hazardous potential of B. thuringiensis. To this end, 39 B. thuringiensis isolates obtained from commercially used biopesticides, various food sources, as well as from foodborne outbreaks were characterized by panC typing, panC-based SplitsTree analysis, toxin gene profiling, FTIR spectroscopic analysis, a cytotoxicity assay screening for enterotoxic activity, and a sphingomyelinase assay. The majority of the tested B. thuringiensis isolates exhibited low (23%, n = 9) or mid level enterotoxicity (74%, n = 29), and produced either no (59%, n = 23) or low levels (33%, n = 13) of sphingomyelinase, which is reported to act synergistically with enterotoxins Nhe and Hbl. One strain isolated from rosemary was however classified as highly enterotoxic surpassing the cytotoxic activity of the high-level reference strain by a factor of 1.5. This strain also produced vast amounts of sphingomyelinase. Combining all results obtained in this study into a fingerprint pattern, several enterotoxic biopesticide strains were indistinguishable from those of isolates from foods or collected in association with outbreaks. Our study shows that many B. thuringiensis biopesticide strains exhibit mid-level cytotoxicity in a Vero cell assay and that some of these strains cannot be differentiated from isolates collected from foods or in association with outbreaks. Thus, we demonstrate that the use of B. thuringiensis strains as biopesticides can represent a food safety risk, underpinning the importance of assessing the hazardous potential of each strain and formulation used.
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Affiliation(s)
- Sophia Johler
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Eva M. Kalbhenn
- Functional Microbiology, Institute of Microbiology, Department of Pathobiology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Nicole Heini
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | | | | | - Murat Bağcioğlu
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
- Functional Microbiology, Institute of Microbiology, Department of Pathobiology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Matthias Contzen
- Chemisches und Veterinäruntersuchungsamt Stuttgart, Fellbach, Germany
| | - Roger Stephan
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Monika Ehling-Schulz
- Functional Microbiology, Institute of Microbiology, Department of Pathobiology, University of Veterinary Medicine Vienna, Vienna, Austria
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Kato K, Matsumura Y, Yamamoto M, Nagao M, Ito Y, Takakura S, Ichiyama S. Erratum to: Seasonal trend and clinical presentation of Bacillus cereus bloodstream infection: association with summer and indwelling catheter. Eur J Clin Microbiol Infect Dis 2016; 35:875-83. [PMID: 27010814 DOI: 10.1007/s10096-016-2618-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Bacillus cereus, an opportunistic pathogen, can cause fatal infection. However, B. cereus bloodstream infections (BSIs) have not been well characterised. From 2008 to 2013, B. cereus isolates from all of the specimens and patients with B. cereus BSIs were identified. Environmental samples were collected to detect B. cereus contamination. We also characterised the clinical presentation of B. cereus BSI through analyses of risk factors for BSI and mortality. A total of 143 clinical B. cereus isolates was detected. Fifty-one patients with nosocomial infections were diagnosed as B. cereus BSI, and 37 had contaminated blood cultures. The number of B. cereus isolates and BSI patients was significantly greater from June to September than from January to April (3.4 vs. 1.0 per month and 1.4 vs. 0.2, respectively). All BSIs were nosocomial and related to central or peripheral vascular catheter. Urinary catheter [odds ratio (OR) 6.93, 95 % confidence interval (CI) 2.40-20.0] was the independent risk factor associated with BSI patients when compared to patients regarded as contaminated. In-hospital mortality among BSI patients was 20 % and was associated with urinary catheter (OR 12.3, 95 % CI 0.67-225, p=0.045) and higher Charlson index (OR 1.99, 95 % CI 1.26-3.12). The number of B. cereus isolates and BSI increased during summer. Inpatients with indwelling vascular or urinary catheters should be carefully monitored for potential B. cereus BSIs.
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Affiliation(s)
- K Kato
- Department of Clinical Laboratory Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin-Kawaharacho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Y Matsumura
- Department of Clinical Laboratory Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin-Kawaharacho, Sakyo-ku, Kyoto, 606-8507, Japan.
| | - M Yamamoto
- Department of Clinical Laboratory Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin-Kawaharacho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - M Nagao
- Department of Clinical Laboratory Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin-Kawaharacho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Y Ito
- Department of Respiratory Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - S Takakura
- Department of Clinical Laboratory Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin-Kawaharacho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - S Ichiyama
- Department of Clinical Laboratory Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin-Kawaharacho, Sakyo-ku, Kyoto, 606-8507, Japan
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Didier A, Jeßberger N, Krey V, Dietrich R, Scherer S, Märtlbauer E. The mutation Glu151Asp in the B-component of the Bacillus cereus non-hemolytic enterotoxin (Nhe) leads to a diverging reactivity in antibody-based detection systems. Toxins (Basel) 2015; 7:4655-67. [PMID: 26569304 PMCID: PMC4663526 DOI: 10.3390/toxins7114655] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 10/29/2015] [Accepted: 11/02/2015] [Indexed: 11/17/2022] Open
Abstract
The ability of Bacillus cereus to cause foodborne toxicoinfections leads to increasing concerns regarding consumer protection. For the diarrhea-associated enterotoxins, the assessment of the non-hemolytic enterotoxin B (NheB) titer determined by a sandwich enzyme immunoassay (EIA) correlates best with in vitro cytotoxicity. In general, the regulation of enterotoxin expression of B. cereus is a coordinately-regulated process influenced by environmental, and probably also by host factors. As long as these factors are not completely understood, the currently-applied diagnostic procedures are based on indirect approaches to assess the potential virulence of an isolate. To date, sandwich EIA results serve as a surrogate marker to categorize isolates as either potentially low or highly toxic. Here, we report on a single amino acid exchange in the NheB sequence leading to an underestimation of the cytotoxic potential in a limited number of strains. During the screening of a large panel of B. cereus isolates, six showed uncommon features with low sandwich EIA titers despite high cytotoxicity. Sequence analysis revealed the point-mutation (Glu)151(Asp) in the potential binding region of the capture antibody. Application of this antibody also results in low titers in an indirect EIA format and shows variable detection intensities in Western-immunoblots. A commercially-available assay based on a lateral flow device detects all strains correctly as NheB producers in a qualitative manner. In conclusion, isolates showing low NheB titers should additionally be assayed in an indirect EIA or for their in vitro cytotoxicity to ensure a correct classification as either low or highly toxic.
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Affiliation(s)
- Andrea Didier
- Department of Veterinary Science, Faculty of Veterinary Medicine, Ludwig-Maximilians Universität München, 85763 Oberschleißheim, Germany.
| | - Nadja Jeßberger
- Department of Veterinary Science, Faculty of Veterinary Medicine, Ludwig-Maximilians Universität München, 85763 Oberschleißheim, Germany.
| | - Victoria Krey
- Lehrstuhl für Mikrobielle Ökologie, Zentralinstitut für Ernährungs-und Lebensmittelforschung, Wissenschaftszentrum Weihenstephan, Technische Universität München, 85354 Freising, Germany.
| | - Richard Dietrich
- Department of Veterinary Science, Faculty of Veterinary Medicine, Ludwig-Maximilians Universität München, 85763 Oberschleißheim, Germany.
| | - Siegfried Scherer
- Lehrstuhl für Mikrobielle Ökologie, Zentralinstitut für Ernährungs-und Lebensmittelforschung, Wissenschaftszentrum Weihenstephan, Technische Universität München, 85354 Freising, Germany.
| | - Erwin Märtlbauer
- Department of Veterinary Science, Faculty of Veterinary Medicine, Ludwig-Maximilians Universität München, 85763 Oberschleißheim, Germany.
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Seasonal trend and clinical presentation of Bacillus cereus bloodstream infection: association with summer and indwelling catheter. Eur J Clin Microbiol Infect Dis 2014; 33:1371-9. [DOI: 10.1007/s10096-014-2083-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 02/17/2014] [Indexed: 12/11/2022]
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Nielsen-LeRoux C, Gaudriault S, Ramarao N, Lereclus D, Givaudan A. How the insect pathogen bacteria Bacillus thuringiensis and Xenorhabdus/Photorhabdus occupy their hosts. Curr Opin Microbiol 2012; 15:220-31. [PMID: 22633889 DOI: 10.1016/j.mib.2012.04.006] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Revised: 04/26/2012] [Accepted: 04/27/2012] [Indexed: 10/28/2022]
Abstract
Insects are the largest group of animals on earth. Like mammals, virus, fungi, bacteria and parasites infect them. Several tissue barriers and defense mechanisms are common for vertebrates and invertebrates. Therefore some insects, notably the fly Drosophila and the caterpillar Galleria mellonella, have been used as models to study host-pathogen interactions for several insect and mammal pathogens. They are excellent tools to identify pathogen determinants and host tissue cell responses. We focus here on the comparison of effectors used by two different groups of bacterial insect pathogens to accomplish the infection process in their lepidopteran larval host: Bacillus thuringiensis and the nematode-associated bacteria, Photorhabdus and Xenorhabdus. The comparison reveals similarities in function and expression profiles for some genes, which suggest that such factors are conserved during evolution in order to attack the tissue encountered during the infection process.
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Affiliation(s)
- Christina Nielsen-LeRoux
- INRA, UMR1319, Micalis, Génétique microbienne et Environnement, La Minière, F-78280 Guyancourt, France.
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Goldstein R, Cheng J, Stec B, Roberts MF. Structure of the S. aureus PI-specific phospholipase C reveals modulation of active site access by a titratable π-cation latched loop. Biochemistry 2012; 51:2579-87. [PMID: 22390775 DOI: 10.1021/bi300057q] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Staphylococcus aureus secretes a phosphatidylinositol-specific phospholipase C (PI-PLC) as a virulence factor that is unusual in exhibiting higher activity at acidic pH values than other enzymes in this class. We have determined the crystal structure of this enzyme at pH 4.6 and pH 7.5. Under slightly basic conditions, the S. aureus PI-PLC structure closely follows the conformation of other bacterial PI-PLCs. However, when crystallized under acidic conditions, a large section of mobile loop at the αβ-barrel rim in the vicinity of the active site shows ~10 Å shift. This loop displacement at acidic pH is the result of a titratable intramolecular π-cation interaction between His258 and Phe249. This was verified by a structure of the mutant protein H258Y crystallized at pH 4.6, which does not exhibit the large loop shift. The intramolecular π-cation interaction for S. aureus PI-PLC provides an explanation for the activity of the enzyme at acid pH and also suggests how phosphatidylcholine, as a competitor for Phe249, may kinetically activate this enzyme.
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Affiliation(s)
- Rebecca Goldstein
- Department of Chemistry, Boston College, Chestnut Hill, Massachusetts 02467, United States
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Horii T, Notake S, Tamai K, Yanagisawa H. Bacillus cereus from blood cultures: virulence genes, antimicrobial susceptibility and risk factors for blood stream infection. ACTA ACUST UNITED AC 2011; 63:202-9. [DOI: 10.1111/j.1574-695x.2011.00842.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | | | - Kiyoko Tamai
- Miroku Medical Laboratory Inc.; Saku; Nagano; Japan
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Klimowicz AK, Benson TA, Handelsman J. A quadruple-enterotoxin-deficient mutant of Bacillus thuringiensis remains insecticidal. Microbiology (Reading) 2010; 156:3575-3583. [DOI: 10.1099/mic.0.039925-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bacillus thuringiensis is the leading biopesticide used to control insect pests worldwide. Although they have a long record of safe use, under certain conditions commercial strains of B. thuringiensis have the ability to produce numerous putative enterotoxins that have been associated with food poisoning attributed to Bacillus cereus. Therefore, we designed a strategy to delete the genes encoding these toxins. B. thuringiensis strain VBTS 2477 contained genes encoding NHE, CytK-2 and three homologues of haemolysin BL (HBL, HBLa1 and HBLa2). This is the first report, to our knowledge, of a strain of B. cereus or B. thuringiensis containing three sets of hbl operons. The genes encoding HBLa1 and HBLa2 were 96–97 % identical to each other and 76–84 % identical to those encoding HBL. The hbla2
operon was detected by PCR amplification only after hbla1
was deleted. We used sequential gene replacement to replace the wild-type copies of the NHE and three HBL operons with copies that contained internal deletions that span the three genes in each operon. The insecticidal activity of the quadruple-enterotoxin-deficient mutant was similar to that of the wild-type strain against larvae of Trichoplusia ni, Spodoptera exigua and Plutella xylostella. This demonstrates that the genes for enterotoxins can be deleted, eliminating the possibility of enterotoxin production without compromising the insecticidal efficacy of a strain of B. thuringiensis.
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Affiliation(s)
- Amy K. Klimowicz
- Departments of Bacteriology and Plant Pathology, University of Wisconsin-Madison, 1550 Linden Dr., Madison, WI, USA
| | - Terry A. Benson
- Valent BioSciences Corporation, Agricultural Research Station, 6131 RFD Oakwood Road, Long Grove, IL, USA
| | - Jo Handelsman
- Departments of Bacteriology and Plant Pathology, University of Wisconsin-Madison, 1550 Linden Dr., Madison, WI, USA
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Raymond B, Johnston PR, Nielsen-LeRoux C, Lereclus D, Crickmore N. Bacillus thuringiensis: an impotent pathogen? Trends Microbiol 2010; 18:189-94. [DOI: 10.1016/j.tim.2010.02.006] [Citation(s) in RCA: 249] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2009] [Revised: 02/18/2010] [Accepted: 02/24/2010] [Indexed: 11/17/2022]
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Pang JC, Chen ML, Ho YC, Yang CY, Tzeng CC, Kao SS, Tsen HY. Effect of fermentation conditions on the enterotoxigenicity, cytotoxicity and pesticidal activity of Bacillus thuringiensis strains isolated in Taiwan. BIORESOURCE TECHNOLOGY 2010; 101:1871-1876. [PMID: 19880313 DOI: 10.1016/j.biortech.2009.09.090] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2009] [Revised: 09/29/2009] [Accepted: 09/30/2009] [Indexed: 05/28/2023]
Abstract
A total of 75 Bacillus thuringiensis strains, among them 62 of Taiwan's microbiota, were screened for their enterotoxin genes, hemolysin BL activity and cytotoxicity. All the strains harbored enterotoxin genes and were cytotoxic to the cultivated Chinese hamster ovary (CHO) cells. The hemolysin BL and cytotoxicity titers of the B. thuringiensis culture in casitone yeast sucrose (CYS) broth were lower than those in brain heart infusion (BHI) broth, and when the B. thuringiensis strains were cultivated in CYS broth for 5 days, no cytotoxicity was detected. The spores and crystal toxins collected from 40 isolates showed high levels of insecticidal activity against Plutella xylostella. All strains exhibiting low cytotoxicity also had low pesticidal activity. Our study demonstrated that it is difficult to find B. thuringiensis strains that are both effective against insect targets and do not produce enterotoxins or cytotoxic effects in CHO cells. However, it is possible to avoid or reduce unwanted properties, but not the insecticidal activity, of some B. thuringiensis preparations by alteration of culture media and conditions.
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Affiliation(s)
- Jen-Chieh Pang
- Department of Biotechnology, Van-Nung University, Chung-Li, Taoyuan County 320, Taiwan, ROC
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Physical characteristics of spores of food-associated isolates of the Bacillus cereus group. Appl Environ Microbiol 2009; 76:982-4. [PMID: 20023097 DOI: 10.1128/aem.02116-09] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
All 47 food-borne isolates of Bacillus cereus sensu stricto, as well as 10 of 12 food-borne, enterotoxigenic isolates of Bacillus thuringiensis, possessed appendages. Spores were moderately to highly hydrophobic, and each had a net negative charge. These characteristics indicate that spores of food-associated B. thuringiensis and not only B. cereus sensu stricto have high potential to adhere to inert surfaces.
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Scarano C, Virdis S, Cossu F, Frongia R, De Santis EPL, Cosseddu AM. The pattern of toxin genes and expression of diarrheal enterotoxins in Bacillus thuringiensis strains isolated from commercial bioinsecticides. Vet Res Commun 2009; 33 Suppl 1:257-60. [DOI: 10.1007/s11259-009-9288-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Ankolekar C, Rahmati T, Labbé RG. Detection of toxigenic Bacillus cereus and Bacillus thuringiensis spores in U.S. rice. Int J Food Microbiol 2009; 128:460-6. [DOI: 10.1016/j.ijfoodmicro.2008.10.006] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2008] [Revised: 09/11/2008] [Accepted: 10/04/2008] [Indexed: 11/16/2022]
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