Identification and characterization of Yersinia intermedia isolated from human feces

Beyond Chloride Brines: Variable Metabolomic Responses in the Anaerobic Organism Yersinia intermedia MASE-LG-1 to NaCl and MgSO4 at Identical Water Activity

Growth in sodium chloride (NaCl) is known to induce stress in non-halophilic microorganisms leading to effects on the microbial metabolism and cell structure. Microorganisms have evolved a number of adaptations, both structural and metabolic, to counteract osmotic stress. These strategies are well-understood for organisms in NaCl-rich brines such as the accumulation of certain organic solutes (known as either compatible solutes or osmolytes). Less well studied are responses to ionic environments such as sulfate-rich brines which are prevalent on Earth but can also be found on Mars. In this paper, we investigated the global metabolic response of the anaerobic bacterium Yersinia intermedia MASE-LG-1 to osmotic salt stress induced by either magnesium sulfate (MgSO4) or NaCl at the same water activity (0.975). Using a non-targeted mass spectrometry approach, the intensity of hundreds of metabolites was measured. The compatible solutes L-asparagine and sucrose were found to be increased in both MgSO4 and NaCl compared to the control sample, suggesting a similar osmotic response to different ionic environments. We were able to demonstrate that Yersinia intermedia MASE-LG-1 accumulated a range of other compatible solutes. However, we also found the global metabolic responses, especially with regard to amino acid metabolism and carbohydrate metabolism, to be salt-specific, thus, suggesting ion-specific regulation of specific metabolic pathways.

Kinetics activity of Yersinia Intermedia Against ZnO Nanoparticles Either Synergism Antibiotics by Double-Disc Synergy Test Method

BACKGROUND

Bacterial resistance to the commonly used antibacterial agents is an increasing challenge in the medicine, and a major problem for the health care systems; the control of their spread is a constant challenge for the hospitals.

OBJECTIVES

In this study, we have investigated the antimicrobial activity of the Zinc Oxide nanoparticles against clinical sample; Yersinia intermedia bacteria.

MATERIALS AND METHODS

Nanoparticle susceptibility constants and death kinetic were used to evaluate the antimicrobial characteristics of the Zinc Oxide (ZnO) against the bacteria. Antimicrobial tests were performed with 10⁸ cfu.mL^-1 at baseline. At first, Minimum Inhibitory Concentration (MIC) of ZnO was determined and then nanoparticle suspension at one and two times of the MIC was used for death kinetic and susceptibility constant assay at 0 to 360 min treatment time.

RESULTS

ZnO nanoparticles with size ranging from 10 to 30 nm showed the highest susceptibility reaction against Y. intermedia (Z=39.06 mL.μg^-1). The process of Y. intermedia death in ZnO suspension was assumed to follow the first-order kinetics and the survival ratio of bacteria decreased with the increasing treatment time. An increased concentration of the nanoparticle was seen to enhance the bactericidal action of the nanoparticle. Then we performed the best ratio of the nanoparticles on semi-sensitive and resistance antibiotic for the bacteria. However, based on experimental results, synergy of ZnO nanoparticles and Oxacilin was determined and Y. intermedia showed a higher sensitivity compared to the ZnO nanoparticles alone.

CONCLUSIONS

The results of the present study illustrates that ZnO has a strong antimicrobial effect and could potentially be employed to aid the bacterial control. It could also improve- antibacterial effects in combination with the antibiotics.

Transcriptome changes associated with anaerobic growth in Yersinia intermedia (ATCC29909)

Background

The yersiniae (Enterobacteriaceae) occupy a variety of niches, including some in human and flea hosts. Metabolic adaptations of the yersiniae, which contribute to their success in these specialized environments, remain largely unknown. We report results of an investigation of the transcriptome under aerobic and anaerobic conditions for Y. intermedia, a non-pathogenic member of the genus that has been used as a research surrogate for Y. pestis. Y. intermedia shares characteristics of pathogenic yersiniae, but is not known to cause disease in humans. Oxygen restriction is an important environmental stimulus experienced by many bacteria during their life-cycles and greatly influences their survival in specific environments. How oxygen availability affects physiology in the yersiniae is of importance in their life cycles but has not been extensively characterized.

Methodology/Principal Findings

Tiled oligonucleotide arrays based on a draft genome sequence of Y. intermedia were used in transcript profiling experiments to identify genes that change expression in response to oxygen availability during growth in minimal media with glucose. The expression of more than 400 genes, constituting about 10% of the genome, was significantly altered due to oxygen-limitation in early log phase under these conditions. Broad functional categorization indicated that, in addition to genes involved in central metabolism, genes involved in adaptation to stress and genes likely involved with host interactions were affected by oxygen-availability. Notable among these, were genes encoding functions for motility, chemotaxis and biosynthesis of cobalamin, which were up-regulated and those for iron/heme utilization, methionine metabolism and urease, which were down-regulated.

Conclusions/Significance

This is the first transcriptome analysis of a non-pathogenic Yersiniaspp. and one of few elucidating the global response to oxygen limitation for any of the yersiniae. Thus this study lays the foundation for further experimental characterization of oxygen-responsive genes and pathways in this ecologically diverse genus.

Characterization of atypical isolates of Yersinia intermedia and definition of two new biotypes

The species Yersinia intermedia is a member of the genus Yersinia which belongs to the Enterobacteriaceae family. This species is divided into eight biotypes, according to Brenner's biotyping scheme. This scheme relies on five tests (utilization of Simmons citrate and acid production from d-melibiose, d-raffinose, alpha-methyl-d-glucoside [alphaMG], and l-rhamnose). The collection of the French Yersinia Reference Laboratory (Institut Pasteur, Paris, France) contained 44 strains that were originally identified as Y. intermedia but whose characteristics did not fit into the biotyping scheme. These 44 strains were separated into two biochemical groups: variant 1 (positive for acid production from l-rhamnose and alphaMG and positive for Simmons citrate utlization) and variant 2 (positive for acid production from l-rhamnose and alphaMG). These atypical strains could correspond to new biotypes of Y. intermedia, to Y. frederiksenii strains having the atypical property of fermenting alphaMG, or to new Yersinia species. These strains did not exhibit growth or phenotypic properties different from those of Y. intermedia and Y. frederiksenii and did not harbor any of the virulence traits usually found in pathogenic species. DNA-DNA hybridizations performed between one strain each of variants 1 and 2 and the Y. intermedia and Y. frederiksenii type strains demonstrated that these variants do belong to the Y. intermedia species. We thus propose that Brenner's biotyping scheme be updated by adding two new biotypes: 9 (for variant 1) and 10 (for variant 2) to the species Y. intermedia.

Clinical features of patients with novel Yersinia species

Our purpose was to describe the clinical features of patients with novel Yersinia species. Between 1985 and 1999; 194 patients had yersinia species isolated from stool specimens, 38 (20%) had non-Yersinia enterocolitica species; 12 (32%) had Yersinia intermedia, 7 (18%) Yersinia fredericksenii, 3 (8%) Yersinia kristensenii, and the remaining 16 (42%) were unclassified non-Yersinia enterocolitica species. The most common presenting symptom was diarrhea alone in 10 (26.3%) patients. Symptoms persisted for >1 month in 54% of cases; 21% had symptoms for <1 week; 18 (47%) patients were taking corticosteroids, acid suppressants, and/or antibiotics when Yersinia was isolated. An immunocompromised state was present in 11 (29%) patients. An immunocompromised host and administration of acid suppressants predicted persistence of symptoms for >1 month. Most [27 (71%)] patients received no treatment; 5 (13%) received antibiotics. In conclusion, novel non-Yersinia enterocolitica species, including Yersinia intermedia, Y. fredericksenii, and Y. kristensenii may represent up to 20% of all Yersinia isolates. Diarrhea is the most common symptom.

Yersinia enterocolitica: the charisma continues

Yersinia enterocolitica, a gram-negative coccobacillus, comprises a heterogeneous group of bacterial strains recovered from animal and environmental reservoirs. The majority of human pathogenic strains are found among distinct serogroups (e.g. O:3, O:5,27, O:8, O:9) and contain both chromosome- and plasmid (60 to 75 kb)-mediated virulence factors that are absent in "avirulent" strains. While Y. enterocolitica is primarily a gastrointestinal tract pathogen, it may produce extraintestinal infections in hosts with underlying predisposing factors. Postinfection sequelae include arthritis and erythema nodosum, which are seen mainly in Europe among patients with serogroups O:3 and O:9 infection and HLA-B27 antigen. Y. enterocolitica is acquired through the oral route and is epidemiologically linked to porcine sources. Bacteremia is prominent in the setting of immunosuppression or in patients with iron overload or those being treated with desferrioxamine. metastatic foci following bacteremia are common and often involve the liver and spleen. Of particular concern is blood transfusion-related bacteremia. Evidence has accumulated substantiating the role of Y. enterocolitica as a food-borne pathogen that has caused six major outbreaks in the United States. The diagnosis of Y. enterocolitica gastroenteritis is best achieved through isolation of the bacterium on routine or selective bacteriologic media. When necessary, serogrouping, biogrouping, and assessment for plasmid-encoded virulence traits may aid in distinguishing virulent from "avirulent" strains. Epidemiologically, outside of identified food-borne outbreaks, the source (reservoir) of Y. enterocolitica in sporadic cases is speculative. Therefore, prevention and control measures are difficult to institute.

Identification of Yersinia species by the API 20E

A prospective study was performed to assess the effectiveness of the API 20E in the identification of 183 Yersinia isolates incubated at 28 degrees C for 18 to 24 h. The results showed an overall correct-identification rate of 90%, with positive predictive values for Yersinia enterocolitica and Yersinia frederiksenii of 94 and 92%, respectively. Yersinia intermedia results were unacceptable.