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

Bacillus cytotoxicus is the thermotolerant representative of the Bacillus cereus group. This group, also known as B. cereus sensu lato, comprises both beneficial and pathogenic members and includes psychrotolerant and thermotolerant species. Bacillus cytotoxicus was originally recovered from a fatal outbreak in France in 1998. This species forms a remote cluster from the B. cereus group members and reliably contains the cytk-1 gene, coding for a cytotoxic variant of cytotoxin K. Although this species was originally thought to be homogenous, intra-species diversity has been recently described with four clades, six random amplified polymorphic DNA (RAPD) patterns, and 11 plasmids profiles. This study aimed to get new insights into the genomic diversity of B. cytotoxicus and to decipher the underlying chromosomal and plasmidial variations among six representative isolates through whole genome sequencing (WGS). Among the six sequenced strains, four fitted the previously described genomic clades A and D, while the remaining two constituted new distinct branches. As for the plasmid content of these strains, three large plasmids were putatively conjugative and three small ones potentially mobilizable, harboring coding genes for putative leaderless bacteriocins. Mobile genetic elements, such as prophages, Insertion Sequences (IS), and Bacillus cereus repeats (bcr) greatly contributed to the B. cytotoxicus diversity. As for IS elements and bcr, IS3 and bcr1 were the most abundant elements and, along with the group II intron B.c.I8, were found in all analyzed B. cytotoxicus strains. When compared to other B. cytotoxicus strains, the type-strain NVH 391-98 displayed a relatively low number of IS. Our results shed new light on the contribution of mobile genetic elements to the genome plasticity of B. cytotoxicus and their potential role in horizontal gene transfer.

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

Applied and Environmental Microbiology ◽

10.1128/aem.00912-14 ◽

2014 ◽

Vol 80 (14) ◽

pp. 4138-4152 ◽

Cited By ~ 22

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.

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Genetic distribution of 295 Bacillus cereus group members based on adk-screening in combination with MLST (Multilocus Sequence Typing) used for validating a primer targeting a chromosomal locus in B. anthracis

Journal of Microbiological Methods ◽

10.1016/j.mimet.2007.10.001 ◽

2007 ◽

Vol 71 (3) ◽

pp. 265-274 ◽

Cited By ~ 17

Author(s):

Jaran S. Olsen ◽

Gunnar Skogan ◽

Else Marie Fykse ◽

Elizabeth L. Rawlinson ◽

Herbert Tomaso ◽

...

Keyword(s):

Bacillus Cereus ◽

Multilocus Sequence Typing ◽

Chromosomal Locus ◽

Bacillus Cereus Group ◽

Group Members ◽

Genetic Distribution

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

Food Microbiology ◽

10.1016/j.fm.2010.03.015 ◽

2011 ◽

Vol 28 (2) ◽

pp. 199-208 ◽

Cited By ~ 59

Author(s):

Tjakko Abee ◽

Masja Nierop Groot ◽

Marcel Tempelaars ◽

Marcel Zwietering ◽

Roy Moezelaar ◽

...

Keyword(s):

Bacillus Cereus ◽

Bacillus Cereus Group ◽

Group Members

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

Journal of Bacteriology ◽

10.1128/jb.01292-07 ◽

2007 ◽

Vol 190 (1) ◽

pp. 112-121 ◽

Cited By ~ 35

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.

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