Germination and outgrowth of spores of Bacillus cereus group members: Diversity and role of germinant receptors

2011 ◽  
Vol 28 (2) ◽  
pp. 199-208 ◽  
Author(s):  
Tjakko Abee ◽  
Masja Nierop Groot ◽  
Marcel Tempelaars ◽  
Marcel Zwietering ◽  
Roy Moezelaar ◽  
...  
Keyword(s):  
Bacillus Cereus ◽  
Bacillus Cereus Group ◽  
Group Members

scholarly journals New Insights into the Potential Cytotoxic Role of Bacillus cytotoxicus Cytotoxin K-1

Toxins ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 698
Author(s):  
Klèma Marcel Koné ◽  
Pauline Hinnekens ◽  
Jelena Jovanovic ◽  
Andreja Rajkovic ◽  
Jacques Mahillon
Keyword(s):  
Bacillus Cereus ◽  
Tetrazolium Salt ◽  
Wild Type ◽  
Foodborne Outbreak ◽  
Pathogenic Role ◽  
Bacillus Cereus Group ◽  
Mtt Method ◽  
High Cytotoxicity ◽  
Type Strains

The thermotolerant representative of the Bacillus cereus group, Bacillus cytotoxicus, reliably harbors the coding gene of cytotoxin K-1 (CytK-1). This protein is a highly cytotoxic variant of CytK toxin, initially recovered from a diarrheal foodborne outbreak that caused the death of three people. In recent years, the cytotoxicity of B. cytotoxicus has become controversial, with some strains displaying a high cytotoxicity while others show no cytotoxicity towards cell lines. In order to better circumscribe the potential pathogenic role of CytK-1, knockout (KO) mutants were constructed in two B. cytotoxicus strains, E8.1 and E28.3. The complementation of the cytK-1 KO mutation was implemented in a mutant strain lacking in the cytK-1 gene. Using the tetrazolium salt (MTT) method, cytotoxicity tests of the cytK-1 KO and complemented mutants, as well as those of their wild-type strains, were carried out on Caco-2 cells. The results showed that cytK-1 KO mutants were significantly less cytotoxic than the parental wild-type strains. However, the complemented mutant was as cytotoxic as the wild-type, suggesting that CytK-1 is the major cytotoxicity factor in B. cytotoxicus.

scholarly journals Prevalence, Genetic Diversity, and Host Range of Tectiviruses among Members of the Bacillus cereus Group

2014 ◽  
Vol 80 (14) ◽  
pp. 4138-4152 ◽  
Author(s):  
Annika Gillis ◽  
Jacques Mahillon
Keyword(s):  
Genetic Diversity ◽  
Bacillus Cereus ◽  
Host Range ◽  
Simple Relationship ◽  
Biological Processes ◽  
Bacillus Cereus Group ◽  
Variable Regions ◽  
Content Type ◽  
The Family ◽  
Group Members

ABSTRACTGIL01, Bam35, GIL16, AP50, and Wip1 are tectiviruses preying on theBacillus cereusgroup. Despite the significant contributions of phages in different biological processes, little is known about the dealings taking place between tectiviruses and their Gram-positive bacterial hosts. Therefore, this work focuses on characterizing the interactions between tectiviruses and theB. cereusgroup by assessing their occurrence and genetic diversity and evaluating their host range. To study the occurrence of tectiviruses in theB. cereusgroup, 2,000 isolates were evaluated using primers designed to be specific to two variable regions detected in previously described elements. PCR and propagation tests revealed that tectivirus-like elements occurred in less than 3% of the isolates. Regardless of this limited distribution, several novel tectiviruses were found, and partial DNA sequencing indicated that a greater diversity exists within the familyTectiviridae. Analyses of the selected variable regions, along with their host range, showed that tectiviruses in theB. cereusgroup can be clustered mainly into two different groups: the ones infectingB. anthracisand those isolated from otherB. cereusgroup members. In order to address the host range of some novel tectiviruses, 120 strains were tested for sensitivity. The results showed that all the tested tectiviruses produced lysis in at least oneB. cereus sensu latostrain. Moreover, no simple relationship between the infection patterns of the tectiviruses and their diversity was found.

scholarly journals Discrimination of the Bacillus cereus Group Members by Pattern Analysis of Random Amplified Polymorphic DNA-PCR

2012 ◽  
Vol 17 (2) ◽  
pp. 83-86 ◽  
Author(s):  
RITSUKO KUWANA ◽  
DAISUKE IMAMURA ◽  
HIROMU TAKAMATSU ◽  
KAZUHITO WATABE
Keyword(s):  
Bacillus Cereus ◽  
Pattern Analysis ◽  
Random Amplified Polymorphic Dna ◽  
Bacillus Cereus Group ◽  
Group Members ◽  
Dna Pcr

scholarly journals Cell Wall Carbohydrate Compositions of Strains from the Bacillus cereus Group of Species Correlate with Phylogenetic Relatedness

2007 ◽  
Vol 190 (1) ◽  
pp. 112-121 ◽  
Author(s):  
Christine Leoff ◽  
Elke Saile ◽  
David Sue ◽  
Patricia Wilkins ◽  
Conrad P. Quinn ◽  
...  
Keyword(s):  
Cell Wall ◽  
Bacillus Cereus ◽  
Cell Walls ◽  
Regulatory Gene ◽  
Severe Pneumonia ◽  
Dependent Manner ◽  
Bacillus Cereus Group ◽  
Group Members ◽  
Cell Wall Carbohydrates ◽  
Clade 1

ABSTRACT Members of the Bacillus cereus group contain cell wall carbohydrates that vary in their glycosyl compositions. Recent multilocus sequence typing (MLST) refined the relatedness of B. cereus group members by separating them into clades and lineages. Based on MLST, we selected several B. anthracis, B. cereus, and B. thuringiensis strains and compared their cell wall carbohydrates. The cell walls of different B. anthracis strains (clade 1/Anthracis) were composed of glucose (Glc), galactose (Gal), N-acetyl mannosamine (ManNAc), and N-acetylglucosamine (GlcNAc). In contrast, the cell walls from clade 2 strains (B. cereus type strain ATCC 14579 and B. thuringiensis strains) lacked Gal and contained N-acetylgalactosamine (GalNAc). The B. cereus clade 1 strains had cell walls that were similar in composition to B. anthracis in that they all contained Gal. However, the cell walls from some clade 1 strains also contained GalNAc, which was not present in B. anthracis cell walls. Three recently identified clade 1 strains of B. cereus that caused severe pneumonia, i.e., strains 03BB102, 03BB87, and G9241, had cell wall compositions that closely resembled those of the B. anthracis strains. It was also observed that B. anthracis strains cell wall glycosyl compositions differed from one another in a plasmid-dependent manner. When plasmid pXO2 was absent, the ManNAc/Gal ratio decreased, while the Glc/Gal ratio increased. Also, deletion of atxA, a global regulatory gene, from a pXO2− strain resulted in cell walls with an even greater level of Glc.

Phylogenetic and toxinogenic characteristics of Bacillus cereus group members isolated from spices and herbs

Food Control ◽  
2018 ◽  
Vol 83 ◽  
pp. 90-98 ◽  
Author(s):  
Hendrik Frentzel ◽  
Britta Kraushaar ◽  
Gladys Krause ◽  
Dorina Bodi ◽  
Heidi Wichmann-Schauer ◽  
...  
Keyword(s):  
Bacillus Cereus ◽  
Bacillus Cereus Group ◽  
Group Members

scholarly journals Enigmatic Pilus-like Endospore Appendages of Bacillus cereus Group Species

2021 ◽  
Vol 22 (22) ◽  
pp. 12367
Author(s):  
Ephrem Debebe Zegeye ◽  
Brajabandhu Pradhan ◽  
Ann-Katrin Llarena ◽  
Marina Aspholm
Keyword(s):  
Bacillus Cereus ◽  
Bacillus Cereus Group ◽  
Functional Roles ◽  
Functional Studies ◽  
Cryo Electron Microscopy ◽  
Abiotic Surfaces ◽  
Genes Encoding ◽  
Group Species ◽  
Bacillus Cereus Sensu Lato

The endospores (spores) of many Bacillus cereus sensu lato species are decorated with multiple hair/pilus-like appendages. Although they have been observed for more than 50 years, all efforts to characterize these fibers in detail have failed until now, largely due to their extraordinary resilience to proteolytic digestion and chemical solubilization. A recent structural analysis of B. cereus endospore appendages (Enas) using cryo-electron microscopy has revealed the structure of two distinct fiber morphologies: the longer and more abundant “Staggered-type” (S-Ena) and the shorter “Ladder-like” type (L-Ena), which further enabled the identification of the genes encoding the S-Ena. Ena homologs are widely and uniquely distributed among B. cereus sensu lato species, suggesting that appendages play important functional roles in these species. The discovery of ena genes is expected to facilitate functional studies involving Ena-depleted mutant spores to explore the role of Enas in the interaction between spores and their environment. Given the importance of B. cereus spores for the food industry and in medicine, there is a need for a better understanding of their biological functions and physicochemical properties. In this review, we discuss the current understanding of the Ena structure and the potential roles these remarkable fibers may play in the adhesion of spores to biotic and abiotic surfaces, aggregation, and biofilm formation.

The power of norms to sway fused group members

2018 ◽  
Vol 41 ◽  
Author(s):  
Winnifred R. Louis ◽  
Craig McGarty ◽  
Emma F. Thomas ◽  
Catherine E. Amiot ◽  
Fathali M. Moghaddam
Keyword(s):  
Evolutionary Anthropology ◽  
Normative Systems ◽  
Violent Extremism ◽  
Identity Fusion ◽  
Group Members

AbstractWhitehouse adapts insights from evolutionary anthropology to interpret extreme self-sacrifice through the concept of identity fusion. The model neglects the role of normative systems in shaping behaviors, especially in relation to violent extremism. In peaceful groups, increasing fusion will actually decrease extremism. Groups collectively appraise threats and opportunities, actively debate action options, and rarely choose violence toward self or others.

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