-
Journal of Clinical Microbiology Jun 1983The name Providencia rustigianii sp. nov. is proposed for a group of organisms previously known as Providencia alcalifaciens biogroup 3. By DNA hybridization, strains of...
The name Providencia rustigianii sp. nov. is proposed for a group of organisms previously known as Providencia alcalifaciens biogroup 3. By DNA hybridization, strains of P. rustigianii were 81 to 99% related to each other at 60 degrees C, but only 44 to 49% related to P. alcalifaciens biogroups 1 and 2 and 26 to 33% related to Providencia stuartii. P. rustigianii could be differentiated from P. alcalifaciens and P. stuartii by simple biochemical tests. P. rustigianii produced acid from D-galactose but not from trehalose; P. stuartii produced acid from both; and P. alcalifaciens produced acid from neither. P. rustigianii could be distinguished from Providencia rettgeri (formerly Proteus rettgeri) by urea hydrolysis and acid production from D-arabitol; P. rustigianii was negative for these two tests, but P. rettgeri was positive. Strains of P. rustiganii were 32 to 34% related to strains of P. rettgeri. Three of the 11 strains of P. rustigianii were isolated from stools, but the sources of the other isolates are unknown. Three strains (27%) were sensitive to colistin, and 82 to 100% were sensitive to ampicillin, carbenicillin, cephalothin, gentamicin, kanamycin, nalidixic acid, streptomycin, and tetracycline. Strain ATCC 33673 (CDC no. 0132-68) is the type strain for this species.
Topics: Anti-Bacterial Agents; DNA, Bacterial; Nucleic Acid Hybridization; Proteus; Providencia
PubMed: 6874899
DOI: 10.1128/jcm.17.6.1057-1060.1983 -
Protein Science : a Publication of the... Jun 2015The existence of N-formylated sugars in the O-antigens of Gram-negative bacteria has been known since the middle 1980s, but only recently have the biosynthetic pathways...
The existence of N-formylated sugars in the O-antigens of Gram-negative bacteria has been known since the middle 1980s, but only recently have the biosynthetic pathways for their production been reported. In these pathways, glucose-1-phosphate is first activated by attachment to a dTMP moiety. This step is followed by a dehydration reaction and an amination. The last step in these pathways is catalyzed by N-formyltransferases that utilize N(10) -formyltetrahydrofolate as the carbon source. Here we describe the three-dimensional structure of one of these N-formyltransferases, namely VioF from Providencia alcalifaciens O30. Specifically, this enzyme catalyzes the conversion of dTDP-4-amino-4,6-dideoxyglucose (dTDP-Qui4N) to dTDP-4,6-dideoxy-4-formamido-d-glucose (dTDP-Qui4NFo). For this analysis, the structure of VioF was solved to 1.9 Å resolution in both its apoform and in complex with tetrahydrofolate and dTDP-Qui4N. The crystals used in the investigation belonged to the space group R32 and demonstrated reticular merohedral twinning. The overall catalytic core of the VioF subunit is characterized by a six stranded mixed β-sheet flanked on one side by three α-helices and on the other side by mostly random coil. This N-terminal domain is followed by an α-helix and a β-hairpin that form the subunit:subunit interface. The active site of the enzyme is shallow and solvent-exposed. Notably, the pyranosyl moiety of dTDP-Qui4N is positioned into the active site by only one hydrogen bond provided by Lys 77. Comparison of the VioF model to that of a previously determined N-formyltransferase suggests that substrate specificity is determined by interactions between the protein and the pyrophosphoryl group of the dTDP-sugar substrate.
Topics: Bacterial Proteins; Catalytic Domain; Crystallography, X-Ray; Formyltetrahydrofolates; Hydroxymethyl and Formyl Transferases; Models, Molecular; Protein Conformation; Providencia
PubMed: 25752909
DOI: 10.1002/pro.2675 -
Indian Journal of Public Health 1994
Review
Topics: Acute Disease; Child, Preschool; Developing Countries; Diarrhea; Enterobacteriaceae Infections; Fluid Therapy; Humans; India; Infant; Infant, Newborn; Intestinal Diseases, Parasitic; Rotavirus Infections
PubMed: 7835992
DOI: No ID Found -
Journal of Veterinary Internal Medicine Sep 2021A severe form of acute hemorrhagic diarrhea syndrome (AHDS) occurred in dogs in the Oslo region of Norway during autumn 2019.
BACKGROUND
A severe form of acute hemorrhagic diarrhea syndrome (AHDS) occurred in dogs in the Oslo region of Norway during autumn 2019.
OBJECTIVES
To characterize the fecal microbiota of dogs with AHDS during the outbreak and compare it to that of healthy dogs from the same period and before the outbreak.
ANIMALS
Dogs with AHDS (n = 50), dogs with nonhemorrhagic diarrhea (n = 3), and healthy dogs (n = 11) were sampled during the outbreak. In addition, 78 healthy dogs from the same region were sampled before the outbreak between 2017 and 2018.
METHODS
Retrospective case-control study. The fecal microbiotas were characterized using 16S rRNA gene amplicon sequencing.
RESULTS
Dogs with AHDS had significantly different microbiota composition (R = .07, P < .001) and decreased intestinal diversity relative to healthy dogs from the outbreak period (median, 2.7; range, 0.9-3.5 vs median, 3.2; range, 2.6-4.0; P < .001). The microbiota in dogs with AHDS was characterized by a decrease of Firmicutes and an outgrowth of Proteobacteria, with increased numbers of Clostridium perfringens and Providencia spp. Among the Providencia spp., 1 showed 100% sequence identity with a Providencia alcalifaciens strain that was cultivated and isolated from the same outbreak. No Providencia spp. was found in healthy dogs sampled before the outbreak.
CONCLUSIONS AND CLINICAL IMPORTANCE
Dogs with AHDS had marked changes in fecal microbiota including increased numbers of Providencia spp. and C. perfringens, which may have contributed to the severity of this illness.
Topics: Animals; Case-Control Studies; Diarrhea; Disease Outbreaks; Dog Diseases; Dogs; Feces; Microbiota; Providencia; RNA, Ribosomal, 16S; Retrospective Studies
PubMed: 34288148
DOI: 10.1111/jvim.16201 -
Frontiers in Cellular and Infection... 2024Acute haemorrhagic diarrhoea syndrome (AHDS) in dogs is a condition of unknown aetiology. is suspected to play a role in the disease as it was commonly found in dogs...
INTRODUCTION
Acute haemorrhagic diarrhoea syndrome (AHDS) in dogs is a condition of unknown aetiology. is suspected to play a role in the disease as it was commonly found in dogs suffering from AHDS during a Norwegian outbreak in 2019. The role of this bacterium as a constituent of the canine gut microbiota is unknown, hence this study set out to investigate its occurrence in healthy dogs using metagenomics.
MATERIALS AND METHODS
To decrease the likelihood of false detection, we established a metagenomic threshold for by spiking culture-negative stool samples with a range of bacterial dilutions and analysing these by qPCR and shotgun metagenomics. The detection limit for was determined and used to establish a metagenomic threshold. The threshold was validated on naturally contaminated faecal samples with known cultivation status for . Finally, the metagenomic threshold was used to determine the occurrence of in shotgun metagenomic datasets from canine faecal samples (n=362) collected in the HUNT One Health project.
RESULTS
The metagenomic assay and qPCR had a detection limit of 1.1x10 CFU per faecal sample, which corresponded to a Cq value of 31.4 and 569 unique mer counts by shotgun metagenomics. Applying this metagenomic threshold to 362 faecal metagenomic datasets from healthy dogs, was found in only 1.1% (95% CI [0.0, 6.8]) of the samples, and then in low relative abundances (median: 0.04%; range: 0.00 to 0.81%). The sensitivity of the qPCR and shotgun metagenomics assay was low, as only 40% of culture-positive samples were also positive by qPCR and metagenomics.
DISCUSSION
Using our detection limit, the occurrence of in faecal samples from healthy dogs was low. Given the low sensitivity of the metagenomic assay, these results do not rule out a significantly higher occurrence of this bacterium at a lower abundance.
Topics: Dogs; Animals; Diarrhea; Feces; Metagenome; Providencia; Bacteria; Metagenomics
PubMed: 38481663
DOI: 10.3389/fcimb.2024.1305742 -
Animals : An Open Access Journal From... Nov 2021An outbreak investigation was initiated in September 2019, following a notification to the Norwegian Food Safety Authority (NFSA) of an unusually high number of dogs...
An outbreak investigation was initiated in September 2019, following a notification to the Norwegian Food Safety Authority (NFSA) of an unusually high number of dogs with acute haemorrhagic diarrhoea (AHD) in Oslo. Diagnostic testing by reporting veterinarians had not detected a cause. The official investigation sought to identify a possible common cause, the extent of the outbreak and prevent spread. Epidemiological data were collected through a survey to veterinarians and interviews with dog owners. Diagnostic investigations included necropsies and microbiological, parasitological and toxicological analysis of faecal samples and food. In total, 511 dogs with acute haemorrhagic diarrhoea were registered between 1 August and 1 October. Results indicated a common point source for affected dogs, but were inconclusive with regard to common exposures. A notable finding was that 134 of 325 faecal samples (41%) cultured positive for . Whole genome sequencing (WGS) of 75 isolates from 73 dogs revealed that strains from 51 dogs belonged to the same WGS clone. Findings point to as implicated in the outbreak, but investigations are needed to reveal the pathogenic potential of in dogs and its epidemiology.
PubMed: 34827932
DOI: 10.3390/ani11113201 -
Journal of Insect Science (Online) May 2023Mexican fruit fly (Anastrepha ludens (Loew)) (Diptera: Tephritidae) represents a major threat to fruit production in the Western Hemisphere. Sterile insect technique is...
Mexican fruit fly (Anastrepha ludens (Loew)) (Diptera: Tephritidae) represents a major threat to fruit production in the Western Hemisphere. Sterile insect technique is used to suppress and eradicate wild populations. Success of this control method necessitates weekly production of hundreds of millions of flies, their sterilization by irradiation, and their aerial release. Diet needed to produce large fly numbers are conducive to the spread of bacteria. Pathogenic bacteria were isolated from 3 rearing facilities and from multiple sources: eggs, larvae, pupae and spent diet, and were found to include some isolates identified to the genus Providencia (Enterobacteriales: Morganellaceae). We identified 41 Providencia isolates and tested their pathogenicity to A. ludens. Based on 16s rRNA sequences, 3 groups were clustered into several species of Providencia with varying capacities to affect the Mexican fruit fly production. Isolates putatively identified as P. alcalifaciens/P. rustigianii were all pathogenic causing larval and pupal yield reduction of 46-64% and 37-57%, respectively. Among them, Providencia isolate 3006 was the most pathogenic reducing larval and pupae yield by 73 and 81%, respectively. Isolates identified as P. sneebia were not pathogenic. The final cluster, P. rettgeri/P. vermicola, were variable in pathogenicity with 3 isolates yielding like the control and the rest causing larval and pupal yield reduction of 26-53% and 23-51%, respectively. Isolates putatively identified as P. alcalifaciens/P. rustigianii were more virulent than P. rettgeri/P. vermicola. Accurate identification of species is needed to diagnose and monitor pathogenic versus nonpathogenic Providencia strains.
Topics: Animals; Tephritidae; Providencia; Virulence; RNA, Ribosomal, 16S; Ovum; Larva; Pupa
PubMed: 37220089
DOI: 10.1093/jisesa/iead024 -
Archives of Razi Institute Jun 2023Probiotics have been used for over a century to prevent and treat diseases. They can reduce the effects of gastroenteritis and are now used to treat acute diarrhea. This...
Probiotics have been used for over a century to prevent and treat diseases. They can reduce the effects of gastroenteritis and are now used to treat acute diarrhea. This study aimed to evaluate the co-aggregative effects of probiotics bacteria against diarrheal causative bacteria. For this purpose, 11 isolates of probiotic bacteria were used in the current study, including three , one , two , three , and two isolates. All isolates were tested for antibiotic susceptibility, autoaggregation ability, adhesion ability, antibacterial activity, acid tolerance, and bile salts tolerance. The results showed that most of them had the ability to autoaggregate after 4 h, with the highest percentage of 57.14% for . For the antibiotic susceptibility test, all the isolates showed resistance against trimethoprim/sulfamethoxazole, except one isolate. Moreover, all the isolates, except one, were susceptible to both vancomycin and tetracycline. All tested isolates had adhesion ability with different survival rates, which reached 34.57% for in acidic conditions. Besides, the highest survival rate was 85.17%, which belonged to , for bile salt tolerance. Probiotic isolates had an antibacterial effect against diarrhea-causative bacteria with an inhibition diameter of 17-49 mm for different spp. and spp. isolates. Furthermore, the co-aggregation ability of probiotic isolates against diarrhea-causative bacteria was studied, and results showed that probiotic isolates had a co-aggregative effect against diarrhea-causative bacteria, , , and , after 24 h of incubation. The highest co-aggregative effect of probiotics isolates belonged to and against with a co-aggregation percentage of 100%, while the lowest co-aggregation rate was 14.29% against . The findings revealed the probiotic properties and co-aggregative effects of probiotic bacteria against diarrhea-causative bacteria.
Topics: Animals; Escherichia coli; Lactobacillus; Anti-Bacterial Agents; Bile Acids and Salts; Diarrhea; Probiotics
PubMed: 38028859
DOI: 10.22092/ARI.2022.359870.2494 -
Proceedings of the National Academy of... Apr 2019It is well-understood that many bacteria have evolved to survive catastrophic events using a variety of mechanisms, which include expression of stress-response genes,...
It is well-understood that many bacteria have evolved to survive catastrophic events using a variety of mechanisms, which include expression of stress-response genes, quiescence, necrotrophy, and metabolic advantages obtained through mutation. However, the dynamics of individuals leveraging these abilities to gain a competitive advantage in an ecologically complex setting remain unstudied. In this study, we observed the saliva microbiome throughout the ecological perturbation of long-term starvation, allowing only the species best equipped to access and use the limited resources to survive. During the first several days, the community underwent a death phase that resulted in a ∼50-100-fold reduction in the number of viable cells. Interestingly, after this death phase, only three species, , , and , all members of the family Enterobacteriaceae, appeared to be transcriptionally active and recoverable. are significant human pathogens, frequently resistant to multiple antibiotics, and recently, ectopic colonization of the gut by oral was documented to induce dysbiosis and inflammation. MetaOmics analyses provided several leads for further investigation regarding the ecological success of the Enterobacteriaceae. The isolates accumulated single nucleotide polymorphisms in known growth advantage in stationary phase alleles and produced natural products closely resembling antimicrobial cyclic depsipeptides. The results presented in this study suggest that pathogenic Enterobacteriaceae persist much longer than their more benign neighbors in the salivary microbiome when faced with starvation. This is particularly significant, given that hospital surfaces contaminated with oral fluids, especially sinks and drains, are well-established sources of outbreaks of drug-resistant Enterobacteriaceae.
Topics: Gastrointestinal Microbiome; Humans; Klebsiella; Microbial Viability; Mouth; Providencia; Saliva
PubMed: 30975748
DOI: 10.1073/pnas.1820594116 -
Journal of Bacteriology Aug 2020Chlorogenic acid (CGA) is a phenolic compound with well-known antibacterial properties against pathogens. In this study, structural and biochemical characterization was...
Chlorogenic acid (CGA) is a phenolic compound with well-known antibacterial properties against pathogens. In this study, structural and biochemical characterization was used to show the inhibitory role of CGA against the enzyme of the shikimate pathway, a well-characterized drug target in several pathogens. Here, we report the crystal structures of dehydroquinate synthase (DHQS), the second enzyme of the shikimate pathway, from (DHQS), in binary complex with NAD and ternary complex with NAD and CGA. Structural analyses reveal that CGA occupies the substrate position in the active site of DHQS, which disables domain movements, leaving the enzyme in an open and catalysis-incompetent state. The binding analyses by isothermal titration calorimetry (ITC) and surface plasmon resonance (SPR) show that CGA binds to DHQS with (equilibrium dissociation constant) values of 6.3 μM and 0.5 μM, respectively. nzyme inhibition studies show that CGA inhibits DHQS with a of 235 ± 21 μM, while it inhibits the growth of , , , and with MIC values of 60 to 100 μM. In the presence of aromatic amino acids supplied externally, CGA does not show the toxic effect. These results, along with the observations of the inhibition of the 3-deoxy-d-arabino-heptulosonate-7-phosphate (DAHP) regulatory domain by CGA in our previous study, suggest that CGA binds to shikimate pathway enzymes with high affinity and inhibits their catalysis and can be further exploited for designing novel drug-like molecules. The shikimate pathway is an attractive target for the development of herbicides and antimicrobial agents, as it is essential in plants, bacteria, and apicomplexan parasites but absent in humans. The enzymes of shikimate pathway are conserved among bacteria. Thus, the inhibitors of the shikimate pathway act on wide range of pathogens. We have identified that chlorogenic acid targets the enzymes of the shikimate pathway. The crystal structure of dehydroquinate synthase, the second enzyme of the pathway, in complex with chlorogenic acid and enzymatic inhibition studies explains the mechanism of inhibition of chlorogenic acid. These results suggest that chlorogenic acid has a good chemical scaffold and have important implications for its further development as a potent inhibitor of shikimate pathway enzymes.
Topics: Anti-Bacterial Agents; Bacterial Proteins; Binding Sites; Catalytic Domain; Chlorogenic Acid; Kinetics; Phosphorus-Oxygen Lyases; Protein Binding; Providencia; Shikimic Acid
PubMed: 32661075
DOI: 10.1128/JB.00248-20