scholarly journals Identification and Functional Characterization of Chicken Toll-Like Receptor 5 Reveals a Fundamental Role in the Biology of Infection with Salmonella enterica Serovar Typhimurium

2005 ◽  
Vol 73 (4) ◽  
pp. 2344-2350 ◽  
Author(s):  
Muhammad Iqbal ◽  
Victoria J. Philbin ◽  
G. S. K. Withanage ◽  
Paul Wigley ◽  
Richard K. Beal ◽  
...  
Keyword(s):  
Salmonella Enterica ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Functional Characterization ◽  
Systemic Infection ◽  
Structural Similarity ◽  
Conserved Sequence ◽  
Receptor Repertoire ◽  
Serovar Typhimurium ◽  
Toll Like Receptor 5

ABSTRACT Toll-like receptors (TLRs) are a major component of the pattern recognition receptor repertoire that detect invading microorganisms and direct the vertebrate immune system to eliminate infection. In chickens, the differential biology of Salmonella serovars (systemic versus gut-restricted localization) correlates with the presence or absence of flagella, a known TLR5 agonist. Chicken TLR5 (chTLR5) exhibits conserved sequence and structural similarity with mammalian TLR5 and is expressed in tissues and cell populations of immunological and stromal origin. Exposure of chTLR5+ cells to flagellin induced elevated levels of chicken interleukin-1β (chIL-1β) but little upregulation of chIL-6 mRNA. Consistent with the flagellin-TLR5 hypothesis, an aflagellar Salmonella enterica serovar Typhimurium fliM mutant exhibited an enhanced ability to establish systemic infection. During the early stages of infection, the fliM mutant induced less IL-1β mRNA and polymorphonuclear cell infiltration of the gut. Collectively, the data represent the identification and functional characterization of a nonmammalian TLR5 and indicate a role in restricting the entry of flagellated Salmonella into systemic sites of the chicken.

scholarly journals Structural and Functional Characterization of ScsC, a Periplasmic Thioredoxin-Like Protein from Salmonella enterica Serovar Typhimurium

2013 ◽  
Vol 19 (13) ◽  
pp. 1494-1506 ◽  
Author(s):  
Mark Shepherd ◽  
Begoña Heras ◽  
Maud E. S. Achard ◽  
Gordon J. King ◽  
M. Pilar Argente ◽  
...  
Keyword(s):  
Salmonella Enterica ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Functional Characterization ◽  
Serovar Typhimurium

scholarly journals Structural and functional characterization of Salmonella enterica serovar Typhimurium YcbL: An unusual Type II glyoxalase

2010 ◽  
Vol 19 (10) ◽  
pp. 1897-1905 ◽  
Author(s):  
Anna L. Stamp ◽  
Paul Owen ◽  
Kamel El Omari ◽  
Charles E. Nichols ◽  
Michael Lockyer ◽  
...  
Keyword(s):  
Salmonella Enterica ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Functional Characterization ◽  
Type Ii ◽  
Serovar Typhimurium ◽  
Unusual Type

scholarly journals Cystathionine β-Lyase Is Important for Virulence of Salmonella enterica Serovar Typhimurium

2004 ◽  
Vol 72 (6) ◽  
pp. 3310-3314 ◽  
Author(s):  
Linda J. Ejim ◽  
Vanessa M. D'Costa ◽  
Nadine H. Elowe ◽  
J. Concepción Loredo-Osti ◽  
Danielle Malo ◽  
...  
Keyword(s):  
Salmonella Enterica ◽  
Biosynthetic Pathway ◽  
Antibacterial Agents ◽  
Antimicrobial Agents ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Systemic Infection ◽  
Bacterial Virulence ◽  
Methionine Biosynthesis ◽  
Insertional Inactivation ◽  
Serovar Typhimurium

ABSTRACT The biosynthesis of methionine in bacteria requires the mobilization of sulfur from Cys by the formation and degradation of cystathionine. Cystathionine β-lyase, encoded by metC in bacteria and STR3 in Schizosaccharomyces pombe, catalyzes the breakdown of cystathionine to homocysteine, the penultimate step in methionine biosynthesis. This enzyme has been suggested to be the target for pyridinamine antimicrobial agents. We have demonstrated, by using purified enzymes from bacteria and yeast, that cystathionine β-lyase is not the likely target of these agents. Nonetheless, an insertional inactivation of metC in Salmonella enterica serovar Typhimurium resulted in the attenuation of virulence in a mouse model of systemic infection. This result confirms a previous chemical validation of the Met biosynthetic pathway as a target for the development of antibacterial agents and demonstrates that cystathionine β-lyase is important for bacterial virulence.

scholarly journals Characterization of a Laboratory-Derived, High-Level Ampicillin-Resistant Salmonella enterica Serovar Typhimurium Strain That Caused Meningitis in an Infant

2002 ◽  
Vol 46 (5) ◽  
pp. 1604-1606 ◽  
Author(s):  
Cheng-Hsun Chiu ◽  
Chishih Chu ◽  
Lin-Hui Su ◽  
Wan-Yu Wu ◽  
Tsu-Lan Wu
Keyword(s):  
Cerebrospinal Fluid ◽  
Salmonella Enterica ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Cloning Vector ◽  
Typhimurium Strain ◽  
Serovar Typhimurium ◽  
High Level ◽  
Lactamase Gene

ABSTRACT A Salmonella enterica serovar Typhimurium strain that harbored a plasmid carrying a TEM-1-type β-lactamase gene was isolated from the blood and cerebrospinal fluid of an infant with meningitis. This 3.2-kb plasmid was further characterized to be a nonconjugative pGEM series cloning vector containing a foreign insert. The strain was likely laboratory derived and contaminated the environment before it caused the infection.

scholarly journals Characterization of the Genomes of a Diverse Collection of Salmonella enterica Serovar Typhimurium Definitive Phage Type 104

2008 ◽  
Vol 190 (24) ◽  
pp. 8155-8162 ◽  
Author(s):  
Fiona J. Cooke ◽  
Derek J. Brown ◽  
Maria Fookes ◽  
Derek Pickard ◽  
Alasdair Ivens ◽  
...  
Keyword(s):  
Salmonella Enterica ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Fragment Size ◽  
Phage Type ◽  
Antibiotic Resistance Genes ◽  
Serovar Typhimurium ◽  
Mlst Type ◽  
Plasmid Profiling ◽  
Type Sequence

ABSTRACT Salmonella enterica serovar Typhimurium definitive phage type 104 (DT104) has caused significant morbidity and mortality in humans and animals for almost three decades. We completed the full DNA sequence of one DT104 strain, NCTC13348, and showed that significant differences between the genome of this isolate and the genome of the previously sequenced strain Salmonella serovar Typhimurium LT2 are due to integrated prophage elements and Salmonella genomic island 1 encoding antibiotic resistance genes. Thirteen isolates of Salmonella serovar Typhimurium DT104 with different pulsed-field gel electrophoresis (PFGE) profiles were analyzed by using multilocus sequence typing (MLST), plasmid profiling, hybridization to a pan-Salmonella DNA microarray, and prophage-based multiplex PCR. All the isolates belonged to a single MLST type, sequence type ST19. Microarray data demonstrated that the gene contents of the 13 DT104 isolates were remarkably conserved. The PFGE DNA fragment size differences in these isolates could be explained to a great extent by differences in the prophage and plasmid contents. Thus, here the nature of variation in different Salmonella serovar Typhimurium DT104 isolates is further defined at the gene and whole-genome levels, illustrating how this phage type evolves over time.

scholarly journals Virulence Plasmid-Borne spvB and spvC Genes Can Replace the 90-Kilobase Plasmid in Conferring Virulence to Salmonella enterica Serovar Typhimurium in Subcutaneously Inoculated Mice

2001 ◽  
Vol 183 (15) ◽  
pp. 4652-4658 ◽  
Author(s):  
Hidenori Matsui ◽  
Christopher M. Bacot ◽  
Wendy A. Garlington ◽  
Thomas J. Doyle ◽  
Steve Roberts ◽  
...  
Keyword(s):  
Salmonella Enterica ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Systemic Infection ◽  
Reticuloendothelial System ◽  
Host Cells ◽  
Virulence Plasmid ◽  
Replication Rate ◽  
Oral Inoculation ◽  
Low Copy Number ◽  
Serovar Typhimurium

ABSTRACT In a mouse model of systemic infection, the spv genes carried on the Salmonella enterica serovar Typhimurium virulence plasmid increase the replication rate of salmonellae in host cells of the reticuloendothelial system, most likely within macrophages. A nonpolar deletion in the spvB gene greatly decreased virulence but could not be complemented by spvBalone. However, a low-copy-number plasmid expressing spvBCfrom a constitutive lacUV5 promoter did complement thespvB deletion. By examining a series of spvmutations and cloned spv sequences, we deduced thatspvB and spvC could be sufficient to confer plasmid-mediated virulence to S. enterica serovar Typhimurium. The spvBC-bearing plasmid was capable of replacing all of the spv genes, as well as the entire virulence plasmid, of serovar Typhimurium for causing systemic infection in BALB/c mice after subcutaneous, but not oral, inoculation. A point mutation in the spvBC plasmid preventing translation but not transcription of spvC eliminated the ability of the plasmid to confer virulence. Therefore, it appears that both spvB and spvC encode the principal effector factors for Spv- and plasmid-mediated virulence of serovar Typhimurium.

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