scholarly journals Novel Structural Elements within the NonproteolyticClostridium botulinumType F Toxin Gene Cluster

2010 ◽  
Vol 77 (5) ◽  
pp. 1904-1906 ◽  
Author(s):  
N. Dover ◽  
J. R. Barash ◽  
K. K. Hill ◽  
J. C. Detter ◽  
S. S. Arnon
Keyword(s):  
Gene Cluster ◽  
Clostridium Botulinum ◽  
Gene Clusters ◽  
Gene Arrangement ◽  
Toxin Gene ◽  
Structural Elements ◽  
Novel Gene ◽  
First Time

ABSTRACTWe sequenced for the first time the complete neurotoxin gene cluster of a nonproteolyticClostridium botulinumtype F. The neurotoxin gene cluster contained a novel gene arrangement that, compared to otherC. botulinumneurotoxin gene clusters, lacked the regulatorybotRgene and contained an intergeniciselement between itsorfX2andorfX3genes.

scholarly journals Genetic Homogeneity of Clostridium botulinum Type A1 Strains with Unique Toxin Gene Clusters

2008 ◽  
Vol 74 (14) ◽  
pp. 4390-4397 ◽  
Author(s):  
Brian H. Raphael ◽  
Carolina Luquez ◽  
Loretta M. McCroskey ◽  
Lavin A. Joseph ◽  
Mark J. Jacobson ◽  
...  
Keyword(s):  
Gene Cluster ◽  
Clostridium Botulinum ◽  
Variable Region ◽  
Type A ◽  
Gene Clusters ◽  
Comparative Genomic ◽  
Toxin Gene ◽  
Strain Atcc ◽  
Nucleotide Polymorphisms ◽  
Single Strain

ABSTRACT A group of five clonally related Clostridium botulinum type A strains isolated from different sources over a period of nearly 40 years harbored several conserved genetic properties. These strains contained a variant bont/A1 with five nucleotide polymorphisms compared to the gene in C. botulinum strain ATCC 3502. The strains also had a common toxin gene cluster composition (ha−/orfX+) similar to that associated with bont/A in type A strains containing an unexpressed bont/B [termed A(B) strains]. However, bont/B was not identified in the strains examined. Comparative genomic hybridization demonstrated identical genomic content among the strains relative to C. botulinum strain ATCC 3502. In addition, microarray data demonstrated the absence of several genes flanking the toxin gene cluster among the ha−/orfX+ A1 strains, suggesting the presence of genomic rearrangements with respect to this region compared to the C. botulinum ATCC 3502 strain. All five strains were shown to have identical flaA variable region nucleotide sequences. The pulsed-field gel electrophoresis patterns of the strains were indistinguishable when digested with SmaI, and a shift in the size of at least one band was observed in a single strain when digested with XhoI. These results demonstrate surprising genomic homogeneity among a cluster of unique C. botulinum type A strains of diverse origin.

scholarly journals Looking for the X Factor in Bacterial Pathogenesis: Association of orfX-p47 Gene Clusters with Toxin Genes in Clostridial and Non-Clostridial Bacterial Species

Toxins ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 19 ◽  
Author(s):  
Maria B. Nowakowska ◽  
François P. Douillard ◽  
Miia Lindström
Keyword(s):  
Gene Cluster ◽  
In Silico ◽  
Botulinum Neurotoxin ◽  
Bacterial Species ◽  
Gene Clusters ◽  
Bacterial Pathogenesis ◽  
Toxin Gene ◽  
Toxin Complex ◽  
Analytical Tools ◽  
Bacillus Isolate

The botulinum neurotoxin (BoNT) has been extensively researched over the years in regard to its structure, mode of action, and applications. Nevertheless, the biological roles of four proteins encoded from a number of BoNT gene clusters, i.e., OrfX1-3 and P47, are unknown. Here, we investigated the diversity of orfX-p47 gene clusters using in silico analytical tools. We show that the orfX-p47 cluster was not only present in the genomes of BoNT-producing bacteria but also in a substantially wider range of bacterial species across the bacterial phylogenetic tree. Remarkably, the orfX-p47 cluster was consistently located in proximity to genes coding for various toxins, suggesting that OrfX1-3 and P47 may have a conserved function related to toxinogenesis and/or pathogenesis, regardless of the toxin produced by the bacterium. Our work also led to the identification of a putative novel BoNT-like toxin gene cluster in a Bacillus isolate. This gene cluster shares striking similarities to the BoNT cluster, encoding a bont/ntnh-like gene and orfX-p47, but also differs from it markedly, displaying additional genes putatively encoding the components of a polymorphic ABC toxin complex. These findings provide novel insights into the biological roles of OrfX1, OrfX2, OrfX3, and P47 in toxinogenesis and pathogenesis of BoNT-producing and non-producing bacteria.

scholarly journals Plasmid-Borne Type E Neurotoxin Gene Clusters in Clostridium botulinum Strains

2013 ◽  
Vol 79 (12) ◽  
pp. 3856-3859 ◽  
Author(s):  
Zhen Zhang ◽  
Hannamari Hintsa ◽  
Ying Chen ◽  
Hannu Korkeala ◽  
Miia Lindström
Keyword(s):  
Gene Cluster ◽  
Gel Electrophoresis ◽  
Clostridium Botulinum ◽  
Southern Hybridization ◽  
Gene Clusters ◽  
Pulsed Field Gel Electrophoresis ◽  
Content Type ◽  
Pulsed Field ◽  
Large Plasmids

ABSTRACTA collection of 36Clostridium botulinumtype E strains was examined by pulsed-field gel electrophoresis (PFGE) and Southern hybridization with probes targeted tobotEandorfX1in the neurotoxin gene cluster. Three strains were found to contain neurotoxin subtype E1 gene clusters in large plasmids of about 146 kb in size.

scholarly journals Genetic Diversity among Clostridium botulinum Strains Harboringbont/A2andbont/A3Genes

2012 ◽  
Vol 78 (24) ◽  
pp. 8712-8718 ◽  
Author(s):  
Carolina Lúquez ◽  
Brian H. Raphael ◽  
Lavin A. Joseph ◽  
Sarah R. Meno ◽  
Rafael A. Fernández ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Clostridium Botulinum ◽  
Type A ◽  
Gene Clusters ◽  
Nucleotide Sequencing ◽  
Toxin Gene ◽  
Content Type ◽  
Geographic Origins ◽  
Diversity Studies ◽  
Insight Into

ABSTRACTClostridium botulinumtype A strains are known to be genetically diverse and widespread throughout the world. Genetic diversity studies have focused mainly on strains harboring one type A botulinum toxin gene,bont/A1, although all reportedbont/Agene variants have been associated with botulism cases. Our study provides insight into the genetic diversity ofC. botulinumtype A strains, which containbont/A2(n= 42) andbont/A3(n= 4) genes, isolated from diverse samples and geographic origins. Genetic diversity was assessed by usingbontnucleotide sequencing, content analysis of thebontgene clusters, multilocus sequence typing (MLST), and pulsed-field gel electrophoresis (PFGE). Sequences ofbontgenes obtained in this study showed 99.9 to 100% identity with otherbont/A2orbont/A3gene sequences available in public databases. The neurotoxin gene clusters of the subtype A2 and A3 strains analyzed in this study were similar in gene content.C. botulinumstrains harboringbont/A2andbont/A3genes were divided into six and two MLST profiles, respectively. Four groups of strains shared a similarity of at least 95% by PFGE; the largest group included 21 out of 46 strains. The strains analyzed in this study showed relatively limited genetic diversity using either MLST or PFGE.

scholarly journals Neurotoxin Gene Clusters in Clostridium botulinum Type Ab Strains

2009 ◽  
Vol 75 (19) ◽  
pp. 6094-6101 ◽  
Author(s):  
Carolina Lúquez ◽  
Brian H. Raphael ◽  
Susan E. Maslanka
Keyword(s):  
Amino Acid ◽  
Nucleotide Sequence ◽  
Amino Acid Sequence ◽  
Clostridium Botulinum ◽  
Gene Diversity ◽  
Gene Clusters ◽  
Toxin Gene ◽  
Predicted Amino Acid Sequence ◽  
Botulinum Type ◽  
Type Ab

ABSTRACT There is limited knowledge of the neurotoxin gene diversity among Clostridium botulinum type Ab strains. Only the sequences of the bont/A and bont/B genes in C. botulinum type Ab strain CDC1436 and the sequence of the bont/B gene in C. botulinum type Ab strain CDC588 have been reported. In this study, we sequenced the entire bont/A- and bont/B-associated neurotoxin gene clusters of C. botulinum type Ab strain CDC41370 and the bont/A gene of strain CDC588. In addition, we analyzed the organization of the neurotoxin gene clusters in strains CDC588 and CDC1436. The bont/A nucleotide sequence of strain CDC41370 differed from those of the known bont/A subtypes A1 to A4 by 2 to 7%, and the predicted amino acid sequence differed by 4% to 14%. The bont/B nucleotide sequence in strain CDC41370 showed 99.7% identity to the sequence of subtype B1. The bont/A nucleotide sequence of strain CDC588 was 99.9% identical to that of subtype A1. Although all of the C. botulinum type Ab strains analyzed contained the two sets of neurotoxin clusters, similar to what has been found in other bivalent strains, the intergenic spacing of p21-orfX1 and orfX2-orfX3 varied among these strains. The type Ab strains examined in this study had differences in their toxin gene cluster compositions and bont/A and bont /B nucleotide sequences, suggesting that they may have arisen from separate recombination events.

scholarly journals TetR Is a Positive Regulator of the Tetanus Toxin Gene in Clostridium tetani and Is Homologous to BotR

1998 ◽  
Vol 66 (12) ◽  
pp. 5698-5702 ◽  
Author(s):  
Jean-Christophe Marvaud ◽  
Ulrich Eisel ◽  
Thomas Binz ◽  
Heiner Niemann ◽  
Michel R. Popoff
Keyword(s):  
Amino Acid ◽  
Tetanus Toxin ◽  
Clostridium Botulinum ◽  
Acid Level ◽  
Amino Acid Level ◽  
Dna Binding Protein ◽  
Gene Overexpression ◽  
Toxin Gene ◽  
Clostridium Tetani ◽  
First Time

ABSTRACT The TetR gene immediately upstream from the tetanus toxin (TeTx) gene was characterized. It encodes a 21,562-Da protein which is related (50 to 65% identity) to the equivalent genes (botR) inClostridium botulinum. TetR has the feature of a DNA binding protein with a basic pI (9.53). It contains a helix-turn-helix motif and shows 29% identity with other putative regulatory genes inClostridium, i.e., uviA from C. perfringens and txeR from C. difficile. We report for the first time the transformation of C. tetani by electroporation, which permitted us to investigate the function of tetR. Overexpression of tetR inC. tetani induced an increase in TeTx production and in the level of the corresponding mRNA. This indicates that TetR is a transcriptional activator of the TeTx gene. Overexpression ofbotR/A (60% identity with TetR at the amino acid level) inC. tetani induced an increase in TeTx production comparable to that for overexpression of tetR. However,botR/C (50% identity with TetR at the amino acid level) was less efficient. This supports that TetR positively regulates the TeTx gene in C. tetani and that a conserved mechanism of regulation of the neurotoxin genes is involved in C. tetaniand C. botulinum.

scholarly journals Genome Sequences of Serratia Strains Revealed Common Genes in Both Serratomolides Gene Clusters

Biology ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 482
Author(s):  
Catarina Marques-Pereira ◽  
Diogo Neves Proença ◽  
Paula V. Morais
Keyword(s):  
Comparative Genomics ◽  
Gene Cluster ◽  
Genomic Analysis ◽  
Gene Clusters ◽  
Biosynthetic Gene ◽  
Genome Sequences ◽  
Biosynthetic Gene Clusters ◽  
Bacteria And Fungi ◽  
Different Strains ◽  
First Time

Serratia strains are ubiquitous microorganisms with the ability to produce serratomolides, such as serrawettins. These extracellular lipopeptides are described as biocides against many bacteria and fungi and may have a nematicidal activity against phytopathogenic nematodes. Serrawettins W1 and W2 from different strains have different structures that might be correlated with distinct genomic organizations. This work used comparative genomics to determine the distribution and the organization of the serrawettins biosynthetic gene clusters in all the 84 publicly available genomes of the Serratia genus. The serrawettin W1 and W2 gene clusters’ organization was established using antiSMASH software and compared with single and short data previously described for YD25TSerratia. Here, the serrawettin W1 gene clusters’ organization is reported for the first time. The serrawettin W1 biosynthetic gene swrW was present in 17 Serratia genomes. Eighty different coding sequence (CDS) were assigned to the W1 gene cluster, 13 being common to all clusters. The serrawettin W2 swrA gene was present in 11 Serratia genomes. The W2 gene clusters included 68 CDS with 24 present in all the clusters. The genomic analysis showed the swrA gene constitutes five modules, four with three domains and one with four domains, while the swrW gene constitutes one module with four domains. This work identified four genes common to all serrawettin gene clusters, highlighting their essential potential in the serrawettins biosynthetic process.

scholarly journals Pseudomonas chlororaphis Produces Two Distinct R-Tailocins That Contribute to Bacterial Competition in Biofilms and on Roots

2017 ◽  
Vol 83 (15) ◽  
Author(s):  
Robert J. Dorosky ◽  
Jun Myoung Yu ◽  
Leland S. Pierson ◽  
Elizabeth A. Pierson
Keyword(s):  
Gene Cluster ◽  
Gene Clusters ◽  
Associated Bacteria ◽  
Content Type ◽  
Bacterial Competition ◽  
Transmission Electron ◽  
Lysis Cassette ◽  
First Time ◽  
Insight Into

ABSTRACT R-type tailocins are high-molecular-weight bacteriocins that resemble bacteriophage tails and are encoded within the genomes of many Pseudomonas species. In this study, analysis of the P. chlororaphis 30-84 R-tailocin gene cluster revealed that it contains the structural components to produce two R-tailocins of different ancestral origins. Two distinct R-tailocin populations differing in length were observed in UV-induced lysates of P. chlororaphis 30-84 via transmission electron microscopy. Mutants defective in the production of one or both R-tailocins demonstrated that the killing spectrum of each tailocin is limited to Pseudomonas species. The spectra of pseudomonads killed by the two R-tailocins differed, although a few Pseudomonas species were either killed by or insusceptible to both tailocins. Tailocin release was disrupted by deletion of the holin gene within the tailocin gene cluster, demonstrating that the lysis cassette is required for the release of both R-tailocins. The loss of functional tailocin production reduced the ability of P. chlororaphis 30-84 to compete with an R-tailocin-sensitive strain within biofilms and rhizosphere communities. Our study demonstrates that Pseudomonas species can produce more than one functional R-tailocin particle sharing the same lysis cassette but differing in their killing spectra. This study provides evidence for the role of R-tailocins as determinants of bacterial competition among plant-associated Pseudomonas in biofilms and the rhizosphere. IMPORTANCE Recent studies have identified R-tailocin gene clusters potentially encoding more than one R-tailocin within the genomes of plant-associated Pseudomonas but have not demonstrated that more than one particle is produced or the ecological significance of the production of multiple R-tailocins. This study demonstrates for the first time that Pseudomonas strains can produce two distinct R-tailocins with different killing spectra, both of which contribute to bacterial competition between rhizosphere-associated bacteria. These results provide new insight into the previously uncharacterized role of R-tailocin production by plant-associated Pseudomonas species in bacterial population dynamics within surface-attached biofilms and on roots.

scholarly journals A Gene Cluster Involved in Degradation of Substituted Salicylates via ortho Cleavage in Pseudomonas sp. Strain MT1 Encodes Enzymes Specifically Adapted for Transformation of 4-Methylcatechol and 3-Methylmuconate

2006 ◽  
Vol 189 (5) ◽  
pp. 1664-1674 ◽  
Author(s):  
Beatriz Cámara ◽  
Piotr Bielecki ◽  
Filip Kaminski ◽  
Vitor Martins dos Santos ◽  
Iris Plumeier ◽  
...  
Keyword(s):  
Gene Cluster ◽  
Gene Clusters ◽  
Gene Arrangement ◽  
Kinetic Properties ◽  
Pseudomonas Sp ◽  
Genes Encoding ◽  
Catechol 1,2 Dioxygenase ◽  
Muconate Cycloisomerase ◽  
Sequence Similarities ◽  
Substrate Spectrum

ABSTRACT Pseudomonas sp. strain MT1 has recently been reported to degrade 4- and 5-chlorosalicylate by a pathway assumed to consist of a patchwork of reactions comprising enzymes of the 3-oxoadipate pathway. Genes encoding the initial steps in the degradation of salicylate and substituted derivatives were now localized and sequenced. One of the gene clusters characterized (sal) showed a novel gene arrangement, with salA, encoding a salicylate 1-hydroxylase, being clustered with salCD genes, encoding muconate cycloisomerase and catechol 1,2-dioxygenase, respectively, and was expressed during growth on salicylate and chlorosalicylate. A second gene cluster (cat), exhibiting the typical catRBCA arrangement of genes of the catechol branch of the 3-oxoadipate pathway in Pseudomonas strains, was expressed during growth on salicylate. Despite their high sequence similarities with isoenzymes encoded by the cat gene cluster, the catechol 1,2-dioxygenase and muconate cycloisomerase encoded by the sal cluster showed unusual kinetic properties. Enzymes were adapted for turnover of 4-chlorocatechol and 3-chloromuconate; however, 4-methylcatechol and 3-methylmuconate were identified as the preferred substrates. Investigation of the substrate spectrum identified 4- and 5-methylsalicylate as growth substrates, which were effectively converted by enzymes of the sal cluster into 4-methylmuconolactone, followed by isomerization to 3-methylmuconolactone. The function of the sal gene cluster is therefore to channel both chlorosubstituted and methylsubstituted salicylates into a catechol ortho cleavage pathway, followed by dismantling of the formed substituted muconolactones through specific pathways.

Sign in / Sign up

Export Citation Format

Share Document