Physical maps of the genomes of three Bacillus cereus strains

Carlson, Cathrine R.; Grønstad, A; Kolstø, Anne‐Brit

doi:10.1128/jb.174.11.3750-3756.1992

Cited by 69 publications

(36 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, recent genome sequencing of the Bacillus cereus reference strain ATCC 14579 revealed the sequence of pBClin15 (11), a 15.1-kb linear plasmid that was previously detected in total DNA preparations from this bacterium (7). Although no experimental evidence is currently available regarding its nature, its genetic organization, similar to that of GIL01 and GIL16, strongly supports the hypothesis that it is a prophage.…”

mentioning

confidence: 71%

GIL16, a New Gram-Positive Tectiviral Phage Related to theBacillus thuringiensisGIL01 and theBacillus cereuspBClin15 Elements

2005

View full text Add to dashboard Cite

One of the most notable characteristics of Tectiviridae resides in their double-layer coats: the doublestranded DNA is located within a flexible lipoprotein vesicle covered by a rigid protein capsid. Despite their apparent rarity, tectiviruses have an extremely wide distribution compared to other phage groups. Members of this family have been found to infect gram-negative (PRD1 and relatives) as well as gram-positive (Bam35, GIL01, AP50, and NS11) hosts. Several reports have shown that tectiviruses infecting gram-negative bacteria are closely related, whereas no information is currently available on the genetic relationship among those infecting gram-positive bacteria. The present study reports the sequence of GIL16, a new isolate originating from Bacillus thuringiensis, and a genetic comparison of this isolate with the tectiviral bacteriophages Bam35 and GIL01, which originated from B. thuringiensis serovars Alesti and Israelensis, respectively. In contrast to PRD1 and its relatives, these are temperate bacteriophages existing as autonomous linear prophages within the host cell. Mutations in a particular motif in both the GIL01 and GIL16 phages are also shown to correlate with a switch to the lytic cycle. Interestingly, both bacterial viruses displayed narrow, yet slightly different, host spectrums. We also explore the hypothesis that pBClin15, a linear plasmid hosted by the Bacillus cereus reference strain ATCC 14579, is also a prophage. Sequencing of its inverted repeats at both extremities and a comparison with GIL01 and GIL16 emphasize its relationship to the Tectiviridae.The bacteriophage GIL01 has a linear double-stranded DNA genome of 14,931 bp delineated by imperfect 73-bp inverted repeats and protected by proteins at its 5Ј ends. GIL01 is a temperate bacteriophage that was isolated from Bacillus thuringiensis serovar Israelensis whose prophage form, designated pGIL01, resides in the host cell as an autonomous linear plasmid without any apparent integration into the host chromosome. It has been suggested that GIL01 belongs to the family Tectiviridae (28), whose members are characterized by the presence of an internal lipid membrane. While tectiviruses infecting gram-negative bacteria have been extensively studied at the genetic level, those infecting gram-positive bacteria remain less well characterized. PRD1, for instance, is the family model and infects bacteria harboring conjugative plasmids of the P, N, or W incompatibility groups, such as Escherichia coli and Salmonella enterica. These plasmids encode the phage receptor but are not otherwise involved in the virus life cycle In addition to GIL01, three other tectiviruses that infect gram-positive bacteria have been identified so far. The bacteriophages AP50 and NS11, isolated from Bacillus anthracis (19) and Bacillus acidocaldarius (23, 24), respectively, have only been morphologically characterized. Bam35 was isolated from B. thuringiensis serovar Alesti in 1978 (1) and was recently sequenced (21), revealing that it differs from GIL01 by 11 bp. A p...

show abstract

mentioning

confidence: 71%

GIL16, a New Gram-Positive Tectiviral Phage Related to theBacillus thuringiensisGIL01 and theBacillus cereuspBClin15 Elements

2005

View full text Add to dashboard Cite

show abstract

“…No hybridization between pGIL01 and the linear molecules present in the type strain of B. cereus sensu stricto (ATCC 14579 T ) (Carlson et al, 1992) and in P. polymyxa (Rosado & Seldin, 1993) could be observed. Although the nature of these extrachromosomal DNA remains uncertain, it is possible that they also belong to the Tectiviridae family, which would further extend the variation spectrum of this interesting family of bacteriophages.…”

Section: Discussionmentioning

confidence: 99%

“…Linear molecules of apparently the same size as pGIL01 were also reported in the type strain of B. cereus (ATCC 14579 T ) (Carlson et al, 1992) and in strain SCE2 of Paenibacillus polymyxa (Rosado & Seldin, 1993). However, hybridization, using pGIL01 as probe, performed on these strains displayed no cross-reaction between these plasmids, suggesting that they are not closely related (data not shown).…”

Section: Uv Irradiation Mitomycin C and Nalidixic Acid Induce Gil01 mentioning

confidence: 91%

pGIL01, a linear tectiviral plasmid prophage originating from Bacillus thuringiensis serovar israelensis

Verheust

Jensen²,

Mahillon

2003

Microbiology

View full text Add to dashboard Cite

Bacillus thuringiensis serovar israelensis harbours, in addition to several circular plasmids, a small linear molecule of about 15 kb. Sequence analysis of this molecule, named pGIL01, showed the presence of at least 30 ORFs, five of which displayed similarity with proteins involved in phage systems: a B-type family DNA polymerase, a LexA-like repressor, two potential muramidases and a DNA-packaging protein (distantly related to the P9 protein of the tectiviral phage PRD1). Experimental evidence confirmed that pGIL01 indeed corresponds to the linear prophage of a temperate phage. This bacteriophage, named GIL01, produces small turbid plaques and is sensitive to organic solvents, which suggests the presence of lipid components in its capsid. Experiments using proteases and exonucleases also revealed that proteins are linked to the genomes of both pGIL01 prophage and GIL01 phage at their 59 extremities. Altogether, these features are reminiscent of those of phages found in the Tectiviridae family, and more specifically of those of PRD1, a broad-host-range phage of Gram-negative bacteria. Dot-blot hybridization, PFGE, PCR and RFLP analyses also showed the presence of pGIL01 variants in the Bacillus cereus group. INTRODUCTIONBacillus thuringiensis, the most widely used entomopathogenic bacterium, belongs to the Bacillus cereus sensu lato group. This cluster also includes B. cereus sensu stricto, an opportunist organism implicated in food poisoning (Granum & Lund, 1997), Bacillus anthracis, a human and animal pathogen, Bacillus mycoides and Bacillus pseudomycoides, characterized by their rhizoid growth (Nakamura, 1998), and the psychrotolerant Bacillus weihenstephanensis (Lechner et al., 1998). Despite their broad virulence, these bacteria are genetically closely related (their 16S RNA gene sequences share more than 99 % identity) and could be regarded as pertaining to a single species (Ash et al., 1991;Helgason et al., 2000).B. thuringiensis strains produce, during their sporulation, crystal toxins (delta-endotoxins) that are highly toxic to a number of insect larvae belonging to the orders Lepidoptera, Diptera and Coleoptera, but harmless to vertebrates. Classically, the numerous entomopathogenic B. thuringiensis strains, which have their own specific insecticidal activity, have been classified in different serotypes on the basis of their flagellar antigens. B. thuringiensis serovar (sv.) israelensis is active against dipteran species and is therefore one of the bioinsecticides of choice to control black flies and mosquitoes, both important vectors of human and animal diseases (for a recent review, see Glare & O'Callaghan, 2000).B. thuringiensis sv. israelensis strain H14 has been reported to contain at least eight DNA molecules, including three small (5?4, 6?7 and 7?6 kb) and four large (128, 145, 240 and 350 kb) circular plasmids, and one linear molecule (G. Jensen & L. Andrup, unpublished results). The pathogenicity of this strain only depends on the presence of the 128 kb plasmid which encodes the Cry and Cyt...

show abstract

“…Among the bacteria analyzed to date, only Streptomyces coelicolor (30), Streptomyces lividans (34,35), Myxococcus xanthus (15), Stigmatella aurantica (44), and Bradyrhizobium japonicum (33) have larger genomes. Most endosporeforming bacteria have smaller genomes (2,10,11,13,27,31), although a strain of Bacillus cereus with a 6.3-Mbp genome has been described (12).…”

Section: Discussionmentioning

confidence: 99%

Physical map of the Clostridium beijerinckii (formerly Clostridium acetobutylicum) NCIMB 8052 chromosome

Wilkinson

Young

1995

J Bacteriol

View full text Add to dashboard Cite

A combined physical and genetic map of the single, circular, 6.7-Mbp chromosome of the NCIMB 8052 strain of Clostridium beijerinckii (formerly Clostridium acetobutylicum) has been constructed by using a combination of cloned DNA fragments as hybridization probes and a bank of strains harboring insertions of the conjugative transposon Tn1545. The positions of 81 restriction endonuclease cleavage sites and 32 genes have been determined. Eight genes concerned with solventogenic fermentation are found at three different locations. The chromosome contains at least 13 rrn operons, 11 of which have been located on the map. Their transcriptional orientation diverges from the presumed location of the replication origin.Clostridium beijerinckii (formerly Clostridium acetobutylicum) is an obligately anaerobic spore-forming bacterium that produces acetone, butanol, and small amounts of ethanol when grown on sugary substrates. This process, known as ABE fermentation, has been used extensively for the industrial scale production of acetone and butanol (28). Several different strains are currently under investigation in various laboratories worldwide. They have been separated into three distinct groups on the basis of their biochemical and physiological characteristics, the extent of hybridization between their DNAs, and macrorestriction fragment profiles of their genomes (54, 57). The NCIMB 8052 strain, which belongs to the group that has the largest chromosome, is amenable to genetic manipulation (59, 60). It lacks the active restriction system that is found in the ATCC 824 strain (38). The NCIMB 8052 strain has no indigenous plasmids, but it supports replication of a variety of vectors based on plasmids from Clostridium butyricum, Enterococcus faecalis, and Streptococcus cremoris (41). They may be introduced by either electroporation (46) or intergeneric conjugation with Escherichia coli donors (56). This strain is also susceptible to Tn1545 mutagenesis (58). Homologous recombination between incoming sequences and their counterparts in the bacterial chromosome has recently been demonstrated (55).As an additional aid to genetic analysis of this organism, we have constructed a physical map of the 6.7-Mbp chromosome using pulsed-field gel electrophoresis (PFGE) (50). The application of PFGE to the analysis of bacterial genomes has revealed that the majority of bacteria have single circular chromosomes. However, several exceptions to this general rule have been described. Some bacteria, such as Borrelia burgdorferi and Rhodococcus fascians, have linear chromosomes (4,20,24), whereas Streptomyces lividans and Streptomyces coelicolor have linear chromosomes that may become circular as a result of deletions spanning both telomeres (34,35). Still others, such as Brucella melitensis and Leptospira interrogans, have segmented genomes (40, 63). The segmented genome of Agrobacterium tumefaciens has one circular and one linear component (1). The results reported here indicate that the NCIMB 8052 strain of C. beijerinckii, like most othe...

show abstract

Physical maps of the genomes of three Bacillus cereus strains

Cited by 69 publications

References 21 publications

GIL16, a New Gram-Positive Tectiviral Phage Related to theBacillus thuringiensisGIL01 and theBacillus cereuspBClin15 Elements

GIL16, a New Gram-Positive Tectiviral Phage Related to theBacillus thuringiensisGIL01 and theBacillus cereuspBClin15 Elements

pGIL01, a linear tectiviral plasmid prophage originating from Bacillus thuringiensis serovar israelensis

Physical map of the Clostridium beijerinckii (formerly Clostridium acetobutylicum) NCIMB 8052 chromosome

Contact Info

Product

Resources

About