CRISPR–
            <i>cas</i>
            Loci Profiling of
            <i>Cronobacter Sakazakii</i>
            Pathovars

Ogrodzki, Pauline; Forsythe, Stephen

doi:10.2217/fmb-2016-0070

Cited by 21 publications

(25 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…3, there were total 8 successive co-oriented cas genes: cas2, cas1, cas6, cas5, cas7, cse2, cas8e and cas3 . In accordance with previous studies1021, the CRISPR-Cas of C. sakazakii is subtype I-E. 89.19% (33/37) of the strains were found to have two common cas genes ( cas1 and cas2) , and the he signature cas gene of type I CRISPR-Cas system ( cas3 ). Eight cas3 genes split into helicase cas3′ and HD nuclease cas3′′ genes.…”

Section: Resultssupporting

confidence: 90%

“…Ogrodzki et al . found 12 different CRISPR spacer arrays in four major sequence types (STs) according to the composition of spacers21. We also found a lot of different CRISPR spacer arrays in this study, moreover, all of them were located in conserved region of C. sakazakii genomes.…”

Section: Resultssupporting

confidence: 60%

“…Previous studies have found that prophages and subtype I-E CRISPR-Cas system exist in the genomes of C. sakazakii strains18192021. However, the characteristic of integrated prophages and CRISPR-Cas system, and their impact on the evolution of C. sakazakii have not been reported.…”

mentioning

confidence: 95%

See 2 more Smart Citations

The driving force of prophages and CRISPR-Cas system in the evolution of Cronobacter sakazakii

Zeng

Zhang

et al. 2017

Sci Rep

View full text Add to dashboard Cite

Cronobacter sakazakii is an important foodborne pathogens causing rare but life-threatening diseases in neonates and infants. CRISPR-Cas system is a new prokaryotic defense system that provides adaptive immunity against phages, latter play an vital role on the evolution and pathogenicity of host bacteria. In this study, we found that genome sizes of C. sakazakii strains had a significant positive correlation with total genome sizes of prophages. Prophages contributed to 16.57% of the genetic diversity (pan genome) of C. sakazakii, some of which maybe the potential virulence factors. Subtype I-E CRISPR-Cas system and five types of CRISPR arrays were found in the conserved site of C. sakazakii strains. CRISPR1 and CRISPR2 loci with high variable spacers were active and showed potential protection against phage attacks. The number of spacers from two active CRISPR loci in clinical strains was significant less than that of foodborne strains, it maybe a reason why clinical strains were found to have more prophages than foodborne strains. The frequently gain/loss of prophages and spacers in CRISPR loci is likely to drive the quick evolution of C. sakazakii. Our study provides a new insight into the co-evolution of phages and C. sakazakii.

show abstract

Section: Resultssupporting

confidence: 90%

Section: Resultssupporting

confidence: 60%

See 1 more Smart Citation

The driving force of prophages and CRISPR-Cas system in the evolution of Cronobacter sakazakii

Zeng

Zhang

et al. 2017

Sci Rep

View full text Add to dashboard Cite

show abstract

“…A multilocus sequence typing (MLST) scheme has been established for the entire Cronobacter genus on the basis of seven housekeeping genes (23). Ogrodzki et al (24) recently reported the existence of one subtype I-E CRISPR-Cas system and many CRISPR arrays in C. sakazakii sequence type 1 (ST1), ST4, ST8, and ST12 strains, which are associated with outbreaks of neonatal meningitis and necrotizing enterocolitis infections. In a previous study, we further classified all of the CRISPR arrays into five types according to their conserved locations in the genome of C. sakazakii and found that the frequent gain/loss of prophages and spacers in CRISPR loci was a likely driver of the rapid evolution of the species (25).…”

mentioning

confidence: 99%

Reconstituting the History of Cronobacter Evolution Driven by Differentiated CRISPR Activity

Zeng¹,

Zhang²,

Wu³

et al. 2018

Appl Environ Microbiol

View full text Add to dashboard Cite

strains harboring the CRISPR-Cas system are important foodborne pathogens causing serious neonatal infections. However, the specific role of the CRISPR-Cas system in bacterial evolution remains relatively unexplored. In this study, we investigated the impact of CRISPR-Cas in evolution and obtained 137 new whole-genome sequences of by next-generation sequencing technology. Among the strains examined (n=240), 90.6% (193/213) of prevalent species ,, and strains had intact CRISPR-Cas systems. Two rare species, (n=2) and (n=6), lacked and preserved the CRISPR-Cas system at a low frequency (1/6), respectively. These results suggest that the presence of one CRISPR-Cas system in is important for the species to maintain genome homeostasis for survival. The ancestral strain was likely to harbored both subtype I-E and I-F CRISPR-Cas systems, during the long evolutionary process, subtype I-E was retained, while subtype I-F selectively degenerated in species and was even lost in the major pathovars. Moreover, significantly higher CRISPR activity was observed in plant-associated species than in the virulence-related species and Similar spacers of CRISPR arrays were rarely found among species, suggesting intensive change through adaptive acquisition and loss. Differentiated CRISPR activity appears to be the product of environmental selective pressure and might contribute to the bidirectional divergence and speciation of This study reports the evolutionary history of under the selective pressure of the CRISPR-Cas system. One CRISPR-Cas system in is important for maintaining genome homeostasis, whereas two types of systems may be redundant and not conducive for acquiring beneficial DNA for environmental adaption and pathogenicity. Differentiated CRISPR activity has contributed to the bidirectional divergence and genetic diversity of This perspective makes a significant contribution to the literature by providing new insights into CRISPR-Cas systems in general, while further expanding the roles of CRISPR beyond conferring adaptive immunity and demonstrating a link to adaptation and species divergence in a genus. Moreover, our study provides new insights into the balance between genome homeostasis and the uptake of beneficial DNA related to CRISPR-based activity in the evolution of .

show abstract

“…The cas protein-coding gene (CRISPRcas) array profiling has been applied to Cronobacter genomes of strains from the same ST. Moreover, it was demonstrated that strains in the same ST are distinguishable according to their spacer arrays (Ogrodzki and Forsythe, 2016). The presence and differentiated activity of CRISPR appear in different Cronobacter species (Zeng et al, 2018).…”

Section: Discussionmentioning

confidence: 99%

Genomic Analysis of Putative Virulence Factors Affecting Cytotoxicity of Cronobacter

Cui

et al. 2020

Front. Microbiol.

View full text Add to dashboard Cite

Cronobacter spp. can cause systemic infections, such as meningitis, sepsis, and necrotizing enterocolitis, in immunocompromised patients, especially neonates. Although some virulence factors have been reported previously, the pathogenesis of Cronobacter remains unclear. In this study, we compared genome sequences from different Cronobacter species, sequence types, and sources, with the virulence genes in the virulence factor database. The results showed that Cronobacter has species specificity for these virulence genes. Additionally, two gene clusters, including sfp encoding fimbriae and hly encoding hemolysin, were discovered. Through cell adhesion, cytotoxicity, and hemolysis assays, we found that the isolates possessing the two gene clusters had higher cytotoxicity and stronger hemolysis capacity than those of other isolates in this study. Moreover, analysis of type VI secretion system (T6SS) cluster and putative fimbria gene clusters of Cronobacter revealed that T6SS have species specificity and isolates with high cytotoxicity possessed more complete T6SS cluster construction than that of the rest. In conclusion, the two novel gene clusters and T6SS cluster were involved in the mechanism underlying the cytotoxicity of Cronobacter.

show abstract

CRISPR– cas Loci Profiling of Cronobacter Sakazakii Pathovars

Cited by 21 publications

References 42 publications

The driving force of prophages and CRISPR-Cas system in the evolution of Cronobacter sakazakii

The driving force of prophages and CRISPR-Cas system in the evolution of Cronobacter sakazakii

Reconstituting the History of Cronobacter Evolution Driven by Differentiated CRISPR Activity

Genomic Analysis of Putative Virulence Factors Affecting Cytotoxicity of Cronobacter

Contact Info

Product

Resources

About