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The American Journal of Tropical... Aug 2019is a member of the family Enterobacteriaceae that has been commonly implicated as a causative agent of diarrheal infection in humans and animals. Recent outbreaks of... (Review)
Review
is a member of the family Enterobacteriaceae that has been commonly implicated as a causative agent of diarrheal infection in humans and animals. Recent outbreaks of in both developing and developed countries have raised public health concerns. Several studies have suggested that can cause diarrhea by invading the intestinal mucosa, although its pathogenicity has not been well established. Often routine laboratory investigations that seek etiological agents of diarrhea do not actively pursue detection. Therefore, routine laboratory diagnosis should be given more attention for better understanding the epidemiology and pathogenicity of .
Topics: Animals; Diarrhea; Disease Outbreaks; Enterobacteriaceae Infections; Feces; Foodborne Diseases; Providencia
PubMed: 31218997
DOI: 10.4269/ajtmh.18-0376 -
PLoS Pathogens Sep 2022Bacteria from the genus Providencia are ubiquitous Gram-negative opportunistic pathogens, causing "travelers' diarrhea", urinary tract, and other nosocomial infections...
Lipopolysaccharide -mediated resistance to host antimicrobial peptides and hemocyte-derived reactive-oxygen species are the major Providencia alcalifaciens virulence factors in Drosophila melanogaster.
Bacteria from the genus Providencia are ubiquitous Gram-negative opportunistic pathogens, causing "travelers' diarrhea", urinary tract, and other nosocomial infections in humans. Some Providencia strains have also been isolated as natural pathogens of Drosophila melanogaster. Despite clinical relevance and extensive use in Drosophila immunity research, little is known about Providencia virulence mechanisms and the corresponding insect host defenses. To close this knowledge gap, we investigated the virulence factors of a representative Providencia species-P. alcalifaciens which is highly virulent to fruit flies and amenable to genetic manipulations. We generated a P. alcalifaciens transposon mutant library and performed an unbiased forward genetics screen in vivo for attenuated mutants. Our screen uncovered 23 mutants with reduced virulence. The vast majority of them had disrupted genes linked to lipopolysaccharide (LPS) synthesis or modifications. These LPS mutants were sensitive to cationic antimicrobial peptides (AMPs) in vitro and their virulence was restored in Drosophila mutants lacking most AMPs. Thus, LPS-mediated resistance to host AMPs is one of the virulence strategies of P. alcalifaciens. Another subset of P. alcalifaciens attenuated mutants exhibited increased susceptibility to reactive oxygen species (ROS) in vitro and their virulence was rescued by chemical scavenging of ROS in flies prior to infection. Using genetic analysis, we found that the enzyme Duox specifically in hemocytes is the source of bactericidal ROS targeting P. alcalifaciens. Consistently, the virulence of ROS-sensitive P. alcalifaciens mutants was rescued in flies with Duox knockdown in hemocytes. Therefore, these genes function as virulence factors by helping bacteria to counteract the ROS immune response. Our reciprocal analysis of host-pathogen interactions between D. melanogaster and P. alcalifaciens identified that AMPs and hemocyte-derived ROS are the major defense mechanisms against P. alcalifaciens, while the ability of the pathogen to resist these host immune responses is its major virulence mechanism. Thus, our work revealed a host-pathogen conflict mediated by ROS and AMPs.
Topics: Animals; Antimicrobial Peptides; Drosophila melanogaster; Hemocytes; Humans; Lipopolysaccharides; Oxygen; Providencia; Reactive Oxygen Species; Virulence Factors
PubMed: 36084158
DOI: 10.1371/journal.ppat.1010825 -
FEMS Immunology and Medical Microbiology Dec 2012The O-polysaccharide chain of the lipopolysaccharide (O-antigen) on the bacterial cell surface is one of the most structurally variable cell components and serves as a...
The O-polysaccharide chain of the lipopolysaccharide (O-antigen) on the bacterial cell surface is one of the most structurally variable cell components and serves as a basis for serotyping of Gram-negative bacteria, including human opportunistic pathogens of the genus Providencia. In this work, the O-antigen of Providencia alcalifaciens O40 was obtained by mild acid degradation of the isolated lipopolysaccharide and studied by chemical methods and high-resolution NMR spectroscopy. The following structure of the O-polysaccharide was established: →4)-β-D-Quip3NFo-(1→3)-α-D-Galp-(1→3)-β-D-GlcpA-(1→3)-β-D-GalpNAc-(1→, where GlcA stands for glucuronic acid and Qui3NFo for 3,6-dideoxy-3-formamidoglucose. The O40-antigen was found to be structurally and serologically related to the O-antigens of P. alcalifaciens O5 and Providencia stuartii O18. The O40-antigen gene cluster between cpxA and yibK was sequenced, and the gene functions were predicted in silico. In agreement with the O-polysaccharide structure established, the genes for the synthesis of dTDP-D-Qui3NFo, UDP-D-Gal, UDP-D-GlcA, and UDP-D-GalNAc as well as those encoding three glycosyltransferases, flippase (Wzx), and O-antigen polymerase (Wzy) were recognized. In addition, homologues of wza, wzb, and wzc genes, which are required for the surface expression of capsular polysaccharides, were found within the gene cluster, suggesting that the O-polysaccharide studied is a part of the capsule-related form of the lipopolysaccharide called K(LPS).
Topics: Biosynthetic Pathways; DNA, Bacterial; Magnetic Resonance Spectroscopy; Molecular Sequence Data; Molecular Structure; Multigene Family; O Antigens; Providencia; Sequence Analysis, DNA
PubMed: 23163869
DOI: 10.1111/1574-695X.12002 -
Microbiology and Immunology 2007Superoxide dismutases convert superoxide anions to molecular oxygen and hydrogen peroxide. These enzymes constitute one of the major defense mechanisms of cells against...
Superoxide dismutases convert superoxide anions to molecular oxygen and hydrogen peroxide. These enzymes constitute one of the major defense mechanisms of cells against oxidative stress and play a role in the pathogenesis of certain invasive bacteria. In this study, we reported for the first time here that Providencia alcalifaciens, a member of the family Enterobacteriaceae, produces a superoxide dismutase (SOD) as a major protein in culture supernatants. This protein was purified by a series of column chromatographic separations. The N-terminal amino acid sequence of the protein was determined to be highly homologous to manganese superoxide dismutase of Escherichia coli or Salmonella reported. The gene (sodA) encoding for SOD of P. alcalifaciens was cloned and sequenced. The sodA-encoded protein has a molecular weight of about 23.5 kDa, and the DNA sequence of P. alcalifaciens sodA gene (627 bp) has about 83% identity to the E. coli SOD gene. We constructed a sodA deletion mutant and its complemented strain of P. alcalifaciens. In J774, a macrophage cell line, the sodA deletion mutant was more susceptible to killing by macrophages than the wildtype strain and its complemented strain. When we injected the mutant strain, its complemented strain and wildtype strain intraperitoneally into DDY strain mice, we found that the sodA deletion mutant proved significantly less virulent while the complemented strain recovered the virulence to the same level of wildtype strain of P. alcalifaciens. These results suggested that manganese superoxide dismutase plays an important role in intracellular survival of P. alcalifaciens.
Topics: Amino Acid Sequence; Animals; Bacterial Proteins; Base Sequence; Cell Line; Cloning, Molecular; Enterobacteriaceae Infections; Gene Deletion; Humans; Macrophages; Male; Mice; Molecular Sequence Data; Providencia; Sequence Analysis, DNA; Superoxide Dismutase
PubMed: 17951985
DOI: 10.1111/j.1348-0421.2007.tb03992.x -
Microbiology Resource Announcements Feb 2022Eight Providencia alcalifaciens isolates from eight different dogs in Norway with acute hemorrhagic diarrhea were sequenced. Based on Illumina and Oxford Nanopore...
Eight Providencia alcalifaciens isolates from eight different dogs in Norway with acute hemorrhagic diarrhea were sequenced. Based on Illumina and Oxford Nanopore Technologies sequencing, all of the genomes were complete and closed after hybrid assembly.
PubMed: 35175129
DOI: 10.1128/mra.00955-21 -
Journal of Clinical Microbiology Dec 1979The O-serotyping scheme for Providencia was tested on Providencia alcalifaciens isolates collected mostly from two hospitals. The specificites of the somatic (O)...
The O-serotyping scheme for Providencia was tested on Providencia alcalifaciens isolates collected mostly from two hospitals. The specificites of the somatic (O) antigens of P. alcalifaciens were found to be different from those of Providencia stuartii, and separation of the Providencia typing scheme to allow separate typing of each species led to more efficient typing. All but 4 of 86 isolates were typable. Eighteen serotypes occurred among 53 typable isolates obtained from a pediatric hospital, and 11 occurred among 19 isolates from a general hospital. Thirty-two percent of the isolates from the pediatric hospital belonged to serotype O3, the most frequently isolated and most widely distributed type. The use of the serotyping scheme for P. alcalifaciens is advocated for further studies to examine strains of the species for enteropathogenic types.
Topics: Agglutination Tests; Proteus; Providencia; Serotyping
PubMed: 521478
DOI: 10.1128/jcm.10.6.761-765.1979 -
BMJ (Clinical Research Ed.) Jul 1989
Topics: Diarrhea; Feces; Humans; Proteus Infections; Providencia; Travel
PubMed: 2504344
DOI: 10.1136/bmj.299.6691.94-a -
The American Journal of Tropical... Sep 2015Providencia alcalifaciens is an emerging bacterial pathogen known to cause acute gastroenteritis in children and travelers. In July 2013, P. alcalifaciens was isolated...
Providencia alcalifaciens is an emerging bacterial pathogen known to cause acute gastroenteritis in children and travelers. In July 2013, P. alcalifaciens was isolated from four children appearing for diarrhea at Kiambu District Hospital (KDH) in Kenya. This study describes the outbreak investigation, which aimed to identify the source and mechanisms of infection. We identified seven primary and four secondary cases. Among primary cases were four mothers who had children and experienced mild diarrhea after eating mashed potatoes. The mothers reported feeding children after visiting the toilet and washing their hands without soap. P. alcalifaciens was detected from all secondary cases, and the isolates were found to be clonal by random amplified polymorphic DNA (RAPD) fingerprinting. Our study suggests that the outbreak was caused by P. alcalifaciens, although no fluid accumulation was observed in rabbit ileal loops. The vehicle of the outbreak was believed to be the mashed potato dish, but the source of P. alcalifaciens could not be confirmed. We found that lack of hygiene, inadequate food storage, and improper hand washing before food preparation was the likely cause of the current outbreak. This is the first report of a foodborne infection caused by P. alcalifaciens in Kenya.
Topics: Adolescent; Child; Diarrhea; Disease Outbreaks; Enterobacteriaceae Infections; Female; Foodborne Diseases; Humans; Kenya; Male; Providencia; Solanum tuberosum
PubMed: 26123962
DOI: 10.4269/ajtmh.15-0126 -
Infection and Immunity Dec 1992Providencia alcalifaciens is a member of the family Enterobacteriaceae. There are reports that P. alcalifaciens can cause diarrhea, but the mechanism(s) by which it...
Providencia alcalifaciens is a member of the family Enterobacteriaceae. There are reports that P. alcalifaciens can cause diarrhea, but the mechanism(s) by which it causes diarrhea is known. We studied P. alcalifaciens isolated from a child and two adults with diarrhea for enteropathogenicity. The three isolates did not exhibit any characteristic adherence to cultured HEp-2 cell monolayers, and they did not produce enterotoxins, cytotoxins, or keratoconjunctivitis in the Sereny test. Two isolates invaded cultured HEp-2 cell monolayers, producing localized bacterial clusters and actin condensation. The pattern of actin condensation was different from that produced by enteropathogenic Escherichia coli but similar to that produced by Shigella flexneri. Invasion and actin condensation were poor for the third isolate. Histology of adult rabbit small intestinal loops inoculated with all three isolates revealed bacterial attachment to, penetration of, and microulcer formation on the surface epithelium and hyperemia, edema, and polymorphonuclear cell infiltration of lamina propria. All the isolates produced diarrhea in rabbits with removable intestinal ties, and some of these rabbits developed hindlimb paralysis. Intestinal histology of the rabbits with removable intestinal ties which developed diarrhea showed changes similar to that in adult rabbits on which ileal loop assays had been performed. Transmission electron microscopy of intestinal tissues also confirmed tissue penetration by the isolates. Nerve tissue histology of two rabbits that developed hindlimb paralysis showed focal mononuclear cell infiltration around peripheral nerve sheaths. It is concluded that some strains of P. alcalifaciens are enteropathogenic and that they cause diarrhea by invading the intestinal mucosal epithelium. However, the relevance to human disease of the hindlimb paralysis observed in this animal model is not clear.
Topics: Animals; Diarrhea; Intestines; Paralysis; Providencia; Rabbits
PubMed: 1452332
DOI: 10.1128/iai.60.12.5017-5024.1992 -
Biology Feb 2023Parasitoids are promising biocontrol agents of the devastating fruit fly, . However, parasitoid performance is a function of several factors, including host-associated...
Parasitoids are promising biocontrol agents of the devastating fruit fly, . However, parasitoid performance is a function of several factors, including host-associated symbiotic bacteria. , , and are among the symbiotic bacteria commonly associated with , and they influence the eco-physiological functioning of this pest. However, whether these bacteria influence the interaction between this pest and its parasitoids is unknown. This study sought to elucidate the nature of the interaction of the parasitoids, , , and with as mediated by symbiotic bacteria. Three types of fly lines were used: axenic, symbiotic, and bacteria-mono-associated (, , and ). The suitable stages of each fly line were exposed to the respective parasitoid species and reared until the emergence of adult flies/parasitoids. Thereafter, data on the emergence and parasitoid fitness traits were recorded. No wasps emerged from the fly lines exposed to . The highest emergence of . and was recorded in the fly lines. The parasitoid progeny from the and fly lines had the longest developmental time and the largest body size. Conversely, parasitoid fecundity was significantly lower in the lines, whereas the lines significantly improved fecundity. These results elucidate some effects of bacterial symbionts on host-parasitoid interactions and their potential in enhancing parasitoid-oriented management strategies against .
PubMed: 36829551
DOI: 10.3390/biology12020274