Proc Natl Acad Sci U S A
April 2024
Anti-microbial resistance (AMR) is one of the greatest threats to global health. The continual battle between the emergence of AMR and the development of drugs will be extremely difficult to stop as long as traditional anti-biotic approaches are taken. In order to overcome this impasse, we here focused on the type III secretion system (T3SS), which is highly conserved in many Gram-negative pathogenic bacteria.
View Article and Find Full Text PDFThe first report of transmissible carbapenem resistance encoded by bla was discovered in Pseudomonas aeruginosa GN17203 in 1988, and bla has since been detected in other bacteria, including Enterobacterales. Currently, many variants of bla exist, and point mutations in the bla promoter have been shown to alter promoter strength. For example, the promoter (Pc) of bla, first reported in P.
View Article and Find Full Text PDFBordetella bronchiseptica injects virulence proteins called effectors into host cells via a type III secretion system (T3SS) conserved among many Gram-negative bacteria. Small proteins called chaperones are required to stabilize some T3SS components or localize them to the T3SS machinery. In a previous study, we identified a chaperone-like protein named Bcr4 that regulates T3SS activity in B.
View Article and Find Full Text PDFAurodox was originally isolated in 1972 as a linear polyketide compound exhibiting antibacterial activity against Gram-positive bacteria. We have since identified aurodox as a specific inhibitor of the bacterial type III secretion system (T3SS) using our original screening system for inhibition of T3SS-mediated hemolysis in enteropathogenic Escherichia coli (EPEC). In this research, we synthesized 15 derivatives of aurodox and evaluated EPEC T3SS inhibitory activity as well as antibacterial activity against EPEC.
View Article and Find Full Text PDFuses a type III secretion system (T3SS) to inject virulence proteins into host cells. Although the T3SS was presumed to be involved in host colonization, efficient secretion of type III secreted proteins from has not been observed. To investigate the roles of type III secreted proteins during infection, we attempted to optimize culture conditions for the production and secretion of a type III secreted protein, BteA, in We observed that efficiently secretes BteA in ascorbic acid-depleted (AsA) medium.
View Article and Find Full Text PDFAccumulating evidence has revealed that lymphoid tissue-resident commensal bacteria (e.g. Alcaligenes spp.
View Article and Find Full Text PDFBordetella species, including B. pertussis, have a type III secretion system that is highly conserved among gram-negative pathogenic bacteria. Genes encoding the component proteins of the type III secretion system are localized at the bsc locus in the Bordetella genome.
View Article and Find Full Text PDFEnteropathogenic Escherichia coli (EPEC) use a type 3 secretion system (T3SS) for injection of effectors into host cells and intestinal colonization. Here, we demonstrate that the multicargo chaperone CesT has two strictly conserved tyrosine phosphosites, Y152 and Y153 that regulate differential effector secretion in EPEC. Conservative substitution of both tyrosine residues to phenylalanine strongly attenuated EPEC type 3 effector injection into host cells, and limited Tir effector mediated intimate adherence during infection.
View Article and Find Full Text PDFBteA is one of the effectors secreted from the Bordetella bronchiseptica type III secretion system. It has been reported that BteA induces necrosis in mammalian cells; however, the roles of BteA during the infection process are largely unknown. In order to investigate the BteA functions, morphological changes of the cells infected with the wild-type B.
View Article and Find Full Text PDFBordetella bronchiseptica is genetically related to B. pertussis and B. parapertussis, which cause respiratory tract infections in humans.
View Article and Find Full Text PDFBordetella bronchiseptica colonizes the respiratory tracts of a wide variety of mammals and causes a range of diseases, from lethal pneumonia to asymptomatic chronic infection. We report the complete genome sequence of Bordetella bronchiseptica strain S798, isolated from a pig with atrophic rhinitis in Japan.
View Article and Find Full Text PDFBordetella bronchiseptica is closely related with B. pertussis and B. parapertussis, the causative agents of whooping cough.
View Article and Find Full Text PDFThe type III secretion system (T3SS) is a sophisticated protein secretion machinery that delivers bacterial virulence proteins into host cells. A needle-tip protein, Bsp22 , is one of the secreted substrates of the T3SS and plays an essential role in the full function of the T3SS in Bordetella bronchiseptica. In this study, we found that BB1618 functions as a chaperone for Bsp22 .
View Article and Find Full Text PDFMicrobiol Immunol
June 2012
The type III secretion system (T3SS) plays a key role in the exertion of full virulence by Bordetella bronchiseptica. However, little is known about the environmental stimuli that induce expression of T3SS genes. Here, it is reported that iron starvation is a signal for T3SS gene expression in B.
View Article and Find Full Text PDFGenetic evidence indicates that only the β-anomer of galactose is transported to Kluyveromyces lactis cells by galactose/glucose transporter Hgt1p, and that aldose-1-epimerase encoded by GAL10 is a prerequisite for growth on galactose. Minor aldose-1-epimerases other than Gal10p also exist in K. lactis.
View Article and Find Full Text PDFBackground: Bordetella pertussis is the primary etiologic agent of the disease pertussis. Universal immunization programs have contributed to a significant reduction in morbidity and mortality of pertussis; however, incidence of the disease, especially in adolescents and adults, has increased in several countries despite high vaccination coverage. During the last three decades, strains of Bordetella pertussis in circulation have shifted from the vaccine-type to the nonvaccine-type in many countries.
View Article and Find Full Text PDFThe type III secretion system (T3SS) is highly conserved in many Gram-negative pathogenic bacteria and functions as an injector of bacterial proteins (effectors) into host cells. T3SSs are involved in establishing disease processes, but this machinery is not essential for bacterial growth or homeostasis. Thus, T3SS is expected to be a candidate therapeutic target, and inhibitors of T3SSs could potentially reduce virulence without causing bacterial death, thereby avoiding any subsequent development of resistance.
View Article and Find Full Text PDFAdipocytokines, such as adiponectin, TNF-alpha, and leptin, are cytokines secreted by visceral adipocytes, and they are associated with metabolic syndrome. Adiponectin is one of the adipocytokines, and is a protein comprised of 244 amino acids. It is known as ACRP30, GBP28, and AdipoQ.
View Article and Find Full Text PDFEHEC is a bacterial pathogen causing diarrhea and hemorrhagic colitis in humans. To exert virulence, EHEC exploits a subset of effectors that are translocated into host cells via the type III secretion system. EspJ, which was recently identified as a type III secreted effector, is conserved in related pathogens such as EPEC and Citrobacter rodentium.
View Article and Find Full Text PDFThe Bordetella pertussis pertussis toxin and pertactin (Prn) are protective antigens and are contained in acellular pertussis vaccines. Polymorphisms in the A subunit of pertussis toxin (PtxA) and pertactin have been proposed to mediate vaccine resistance and contribute to pertussis reemergence. To test this hypothesis, previous studies compared clinical isolates expressing different alleles for the proteins.
View Article and Find Full Text PDFThe inflammatory response is one of several host alert mechanisms that recruit neutrophils from the circulation to the area of infection. We demonstrate that Bordetella, a bacterial pathogen, exploits an antiinflammatory cytokine, interleukin-10 (IL-10), to evade the host immune system. We identified a Bordetella effector, BopN, that is translocated into the host cell via the type III secretion system, where it induces enhanced production of IL-10.
View Article and Find Full Text PDFTanpakushitsu Kakusan Koso
June 2009