Genera Of Enterobacteriaceae Research Articles

The phyllosphere indigenous microbiota of Brassica campestris L. change its diversity in responding to di-n-butyl phthalate pollution.

In this study, the effects of di-n-butyl phthalate (DBP) on the phyllosphere bacterial community of field mustard (Brassica campestris L.) at the five-leaf stage were investigated. The indigenous alpha-diversity of the phyllosphere bacteria was altered after spraying with different concentrations of DBP. Shannon diversity indices were significantly changed on day 5 after treatment at DBP concentrations > 400mgL-1 (P > 0.05). Nevertheless, the difference between treatment and control was not significant on day 9 after DBP treatment (P > 0.05). Exposure to DBP resulted in a decrease in Proteobacteria and Firmicutes, and an increase in Actinobacteria at all sampling intervals. These changes included significant increases in the relative abundance of Paracoccus and Rhodococcus, and significant decreases in that of Pseudomonas, Exiguobacterium, an unclassified genus of Pseudomonadaceae, and an unclassified genus of Enterobacteriaceae. This study provides new evidence for the possibility of using phyllosphere microbiota to remediate DBP contamination.

Microbiological contamination of reusable plastic bags for food transportation

Nowadays, with so many concerns for the environment, the use of reusable plastic bags is becoming routine, instead of the use of polluting single-use plastic bags. However, this is controversial in terms of food safety, since consumers transport many different foods, which could contaminate their bags and pose a risk to their health due to cross-contamination.This study aimed to detect or enumerate several indicators/pathogens from 30 used reusable plastic (polypropylene) bags and, to evaluate their antibiotic resistance profiles after identification by 16s rRNA of each isolated microorganism. Several genera of Enterobacteriaceae, coagulase-negative staphylococci and also Listeria monocytogenes were found in the reusable plastic bags analyzed. In general, high percentages of antibiotics resistance were found, highlighting the elevated occurrence of multi-resistant isolates of coagulase-negative staphylococci and Enterobacteriaceae. This study demonstrates the level and variety of microbial contamination of some used reusable plastic bags. No correlation was found between microbial levels and the visual appearance of each bag demonstrating that appearance is not a reliable datum about the bag contamination. We believe that this study could help the competent authorities taking measures to alert consumers to good food safety practices, not only in their kitchens, but also in the bags that carry their food.

704. Klebsiella pneumoniae Carbapenemase and Verona Integron-Encoded Metallo-β-Lactamase Among Carbapenem-Resistant Enterobacteriaceae in Kentucky

Background Klebsiella pneumoniae carbapenemase (KPC) and Verona integron-encoded metallo-β-lactamase (VIM) have been the most commonly identified carbapenemases among carbapenemase-producing carbapenem-resistant Enterobacteriaceae (CP-CRE) in Kentucky since 2013. Understanding the frequency and epidemiology of these CP-CRE can help inform prevention strategies.MethodsWe reviewed reports of KPC- and VIM-producing CRE from January 2013 through December 2017. CRE became reportable in Kentucky in February 2015 and statewide request to laboratories and healthcare facilities for isolate submission for mechanism testing was made in September 2017. Prior to that time, mechanism testing for CRE was conducted at a limited number of laboratories or during outbreak investigations. Demographic data included age, sex, and inpatient or outpatient status. Descriptive analyses were performed.ResultsAs of December 31, 2017, a total of 156 CP-CRE isolates had been identified (124 KPC, 31 VIM, 1 NDM), with an increase from 2013 (n = 13) to 2017 (n = 48). KPC was identified in isolates from 124 patients; VIM was identified in isolates from 26 patients, with 4 patients (15%) having multiple organisms with the mechanism. KPC was identified most commonly from Klebsiella pneumoniae (57/124, 46%); VIM was identified most commonly from Enterobacter cloacae (14/31, 45%). KPC was found in 6 different Enterobacteriaceae genera; VIM in 4. KPC-producing CRE were identified in 22 acute-care and long-term acute-care facilities in 14 counties, with nine reporting >2 isolates. Fifteen percent (19/124) of KPC-producing CRE were isolated from outpatients. VIM-producing CRE were identified in two acute-care facilities located in two urban areas; one was from an outpatient. Patients with VIM were younger than those with KPC (43 vs. 60 years, P < 0.001).ConclusionKPC is the predominant carbapenemase in Kentucky and is more widely disseminated than VIM, which has been limited to two facilities. CRE reporting and mechanism testing have yielded a greater understanding of regional CRE epidemiology and has the potential to facilitate response efforts to slow further spread.Disclosures All authors: No reported disclosures.

Dietary Deoxynivalenol Contamination and Oral Lipopolysaccharide Challenge Alters the Cecal Microbiota of Broiler Chickens.

Dietary deoxynivalenol (DON) impairs the intestinal functions and performance in broiler chickens, whereas little is known about the effect of DON on the gastrointestinal microbiota. This study evaluated the impact of graded levels of dietary DON contamination on the cecal bacterial microbiota, their predicted metabolic abilities and short-chain fatty acid (SCFA) profiles in chickens. In using a single oral lipopolysaccharide (LPS) challenge we further assessed whether an additional intestinal stressor would potentiate DON-related effects on the cecal microbiota. Eighty 1-day-old chicks were fed diets with increasing DON concentrations (0, 2.5, 5, and 10 mg DON per kg diet) for 5 weeks and were sampled after half of the chickens received an oral LPS challenge (1 mg LPS/kg bodyweight) 1 day before sampling. The bacterial composition was investigated by Illumina MiSeq sequencing of the V3–5 region of the 16S rRNA gene. DON-feeding decreased (p < 0.05) the cecal species richness (Chao1) and evenness (Shannon) compared to the non-contaminated diet. The phyla Firmicutes and Proteobacteria tended to linearly increase and decrease with increasing DON-concentrations, respectively. Within the Firmicutes, DON decreased the relative abundance of Oscillospira, Clostridiaceae genus, Clostridium, and Ruminococcaceae genus 2 (p < 0.05), whereas it increased Clostridiales genus 2 (p < 0.05). Moreover, increasing DON levels linearly decreased a high-abundance Enterobacteriaceae genus and an Escherichia/Shigella-OTU (p < 0.05). Changes in the bacterial composition and their imputed metagenomic capabilities may be explained by DON-related changes in host physiology and cecal nutrient availability. The oral LPS challenge only decreased the abundance of an unassigned Clostridiales genus 2 (p = 0.03). Increasing dietary concentrations of DON quadratically increased the cecal total SCFA and butyrate concentration (p < 0.05), whereas a DON × LPS interaction indicated that LPS mainly increased cecal total SCFA, butyrate, and acetate concentrations in chickens fed the diets that were not contaminated with DON. The present findings showed that even the lowest level of dietary DON contamination had modulatory effects on chicken's cecal bacterial microbiota composition and diversity, whereas the additional oral challenge with LPS did not potentiate DON effects on the cecal bacterial composition.

Characteristics of the composition of the psychrotrophic microflora of frozen beef in the process of storage

In the technological process of obtaining raw materials and food products, the main task is to ensure their safety. During the curing of beef meat, the risks are most often associated with microbial contamination. The purpose of the work was to investigate the dynamics of quantitative content and generic composition of psychrotrophic microflora in the process of storage of frozen beef with different initial microbial sowing. The investigated samples were divided into four groups, depending on the initial content of the psychrotrophic microflora. The first group of psychrotrophic microorganisms was up to 103 CFU/cm3 from the surface; second group of 103 to 104 CFU/cm3 of washed away; the third – from 104 to 105 CFU/cm3 of washed away; the fourth is more than 105 CFU/cm3 of washed away. It was established that during the storage of beef in the frozen state, the rate of development of the psychrotrophic microflora is 3,0-32,6 times faster than the mesophilic microflora. Also it was found the higher the initial microbial sowing of beef, the faster the pace of development of the microflora in the process of storing meat in the frozen state. Therefore, when choosing meat storage conditions (temperature, term), the initial microbial contamination of the carcass surface with a psychrotrophic microflora is important. It was found that from beef with low microbial sowing it is allocated three classes of psychrotrophic bacteria: Acinetobacter, Alcaligenes i Pseudomonas. The largest part of the cooled meat was 56.2 ± 2.4% of the genus Acinetobacter, and the smallest 12.5 ± 0.8% Pseudomonas. After 20 days of storage of beef in the frozen state, the growth of bacteria of the genus Pseudomonas was 1,4 times (P ≤ 0.05) due to the reduction of the Acinetobacter species of microorganisms. At the same time, the bacteria of the genus Alcaligenes were stably high in both frosty and frozen meat – 31.2–32.7%, respectively. Identification of psychrotrophic microflora with an initial content of mesophilic and psychrotrophic microorganisms 6.5 ± 0.5×103 and 4.2 ± 0.2×103 CFU/cm3 of the washed away, has established an increase in the number of identified genera. Among the already identified three genera in the washed away from beef of this group, bacteria of the genus Flavobacterium i Aeromonas are isolated, both in frozen meat and after storage in a frozen state. When identifying a psychrotrophic microflora with a significant initial microbial sowing (the number of mesophilic bacteria is greater than 5.9 ± 0.4 × 104 and psychrotrophic 3.7 ± 0.2×104 CFU/cm3 washed away the surface) was established an increase in generic composition. Thus, in the psychrotrophic microflora, 5 to 10% of bacteria of the Enterobacteriaceae genus, gram-positive sticks and cow's bacterial forms began to stand out from 3 to 5%. Consequently, the conducted searches have found that with an increase in the initial microbial contamination of beef, the quantitative genetic composition of the psychrotrophic microflora increases. As a result, the storage period of frozen beef and the hygienic and technological quality of meat is reduced.

Detection and Identification of Potato Soft Rot &amp;lt;i&amp;gt;Pectobacterium carotovorum&amp;lt;/i&amp;gt; Subspecies &amp;lt;i&amp;gt;carotovorum&amp;lt;/i&amp;gt; by PCR Analysis of 16S rDNA in Jordan

Various bacterial species are known to be agents causing soft rot of potatoes. The results of this study showed that potato soft rot is widely spread in different potato planting areas in Jordan. A survey was conducted through the years 2013-2015 to detect potato soft rot disease in Jordan, two hundred and four rotted potato samples were collected from different potato growing areas through different potato growing seasons. One hundred and thirty one bacterial isolates were isolated, purified on selective media and identified as Pectobacterium carotovorum subspecies carotovorum (Pcc) by different biochemical and physiological tests. Furthermore, 131 Pcc Jordanian (Jo) isolates were identified by PCR analysis of total DNA extracted from isolates that were biochemically identified as Pcc using universal primer Fd1/Rd1. Cloning and sequencing of representative PCR products, amplifying the 16S rDNA region were done. Phylogenetic analysis of the Pcc Jo-isolates revealed other than 90% similarity with different reference Pcc strains available at the GenBank. Different rot causal agents also were detected by PCR amplification and further sequences. The sequencing data revealed similarities to Pseudomonas fluorescence, Enterobacteriaceae genera such as Enterobacter spp., Serratia spp. and Klebsiella spp., in addition to Pectobacterium carotovorum subsp. carotovorum. This study indicated that using molecular techniques such as amplification of 16S rDNA region is a sensitive and specific method for detecting Pcc as potato soft rot causal agent. So far this is the first study where Pcc has been identified by using PCR and sequencing approaches in Jordan.

Bacterial Communities Associated With the Pine Wilt Disease Vector Monochamus alternatus (Coleoptera: Cerambycidae) During Different Larval Instars

We investigated the influence of larval instar on the structure of the gut bacterial community in the Japanese pine sawyer, Monochamus alternatus (Hope; Coleoptera: Cerambycidae). The diversity of the gut bacterial community in early, phloem-feeding larvae is significantly higher than in later, wood-feeding larvae. Many of these associates were assigned into a few taxonomic groups, of which Enterobacteriaceae was the most abundant order. The predominant bacterial genus varied during the five instars of larval development. Erwinia was the most abundant genus in the first and fifth instars, Enterobacter was predominant in the third and fourth instars, and the predominant genus in the second instars was in the Enterobacteriaceae (genus unclassified). Actinobacteria were reported in association with M. alternatus for the first time in this study. Cellulomonadaceae (Actinobacteria) was the second most abundant family in the first instar larvae (10.6%). These data contribute to our understanding of the relationships among gut bacteria and M. alternatus, and could aid the development of new pest control strategies.

English

Potato soft rot is one of the major destructive diseases affecting potato plants throughout the world. In a survey of different potato growing seasons in different regions of Jordan, samples of rotten potato tubers were collected and 131 isolates identified biochemically as Pectobacterium carotovorum subsp. carotovorum (Pcc). The PCR primer pair (EXPCCR/EXPCCF) was used to detect these Jordanian isolates. The primer set amplified a single fragment of 550 bp in size from the total genomic DNA, which was extracted independently from 67 Pcc strains. In a nested PCR, the primer set (INPCCR/INPCCF) amplified the expected single fragment of 400 bp from the PCR product of first PCR amplification. The use of these primers was not reliable in detecting all isolates identified biochemically as Pcc. Different rots causal agents were detected by PCR amplification and further sequenced. The sequencing data revealed similarities to different genera; Pseudomonas, Enterobacteriaceae genera such as Enterobacter spp., Serratia spp. and Klebsiella spp., in addition to P. carotovorum subsp. carotovorum. So far this is the first study where Pcc has been identified by using PCR and sequencing approaches in Jordan. &nbsp; Key words: Pectobacterium carotovorum subsp. carotovorum, specific primers, nested PCR, sequencing. &nbsp

Influence of a device intravaginal to synchronization/induction of estrus and its reuse in sheep vaginal flora

The objective of this study was to characterize the vaginal bacterial flora and their antibiotic susceptibility in vitro after, application, and the reuse of an intravaginal progesterone device (CIDR) in controlling the estrous cycle in sheep. Thirty Texel ewe lambs were used, after carefully assessed on their health and body condition. Experimental groups were formed by new CIDR (CIDRn, n = 15) and CIDR reused (CIDRu, n = 15). Treatment with progesterone lasted 6 days. Sterile swabs were used for vaginal sample collection, a procedure performed previously of CIDR insertion and on the moment of CIDR removing. The predominant flora prior to insertion of intravaginal devices proved to be 93.3% (14/15) and 80.0% (12/15) of gram-positive agents, especially of the genera Bacillus sp. and Staphylococcus sp. in CIDRn CIDRu groups, respectively. Upon removal of the devices, however, it was observed that the emergence of gram-negative agents in 100% of the samples CIDRn, most of them belonging to the Enterobacteriaceae genus. In CIDRu group, there was a balance between negative- and gram-positive agents on the removal of the devices. Regarding to susceptibility, our findings revelated some degree of resistance in all samples. Therefore, our conclusions pointed out that intravaginal devices (CIDR), when employed in the first use, or reuse, for a period of 6 days, promote a change in vaginal flora of sheep, highlighting the predominance of gram-negative agents during its removal.

Rapid Detection of Serratia fonticola by TaqMan Quantitative Real-Time PCR Using Primers Targeting the gyrB Gene.

A gyrB gene is present in the majority of bacterial species, and encodes the ATPase domain of DNA gyraseB-subunit protein, which is essential for transcription and replication of bacteria. The gyrB gene exhibits higher nucleotide sequence variability than the 16S rDNA gene and thus could be more reliable in differentiating Serratia fonticola. A species-specific primer pair and probe were designed for quantitative real-time PCR detection of S. fonticola using gyrB as the target gene. Nine members of the Serratia family (representing nine Serratia species) were chosen to verify the specificity of the primers. Additionally, two species each of Salmonella and Klebsiella, and five other species belonging to five other genera of Enterobacteriaceae, were tested for primer cross-reaction. All the tested strains gave negative results. The limit of detection for S. fonticola using the gyrB gene was 100 copies per PCR reaction. This TaqMan PCR assay provided a specific, rapid, and sensitive method to detect S. fonticola based on its gyrB gene.

Variability in gut microbiota response to an inulin-type fructan prebiotic within an in vitro three-stage continuous colonic model system

Gut microbiota have a major influence on human health and disease. Dietary interventions have been shown to beneficially modulate the gut microbiota and improve health; however, it appears there is large inter-individual variability in gut microbiota responsiveness to dietary interventions. We aimed to determine whether different fermentable carbohydrate content media, mimicking Western and Prudent style dietary patterns, influence gut microbiota response to an inulin-type fructan prebiotic using an in vitro three-stage continuous colonic model system. We demonstrated that the addition of an inulin-type fructan prebiotic led to shifts in the organic acid concentrations and bacterial taxa in both the low (LF) and high fermentable carbohydrate medium (HF) gut models. The shifts that occurred after the addition of the prebiotic significantly differed between the LF and HF gut models. Acetate increased in the HF gut models but decreased in the LF gut models (p=0.021). The increases that occurred in Firmicutes (p=0.026), Lactobacillus (p=0.045) and Mitsuokella (p=0.012) were significantly greater in the HF gut models. Megasphaera (p=0.033) and an unknown genus of Enterobacteriaceae (p=0.011) decreased in the LF gut models but increased in the HF gut models. The reduction in an unknown genus of Lachnospiraceae (other) was significantly greater in LF gut models (p=0.040). Additionally, large inter- and intra-donor variability in gut microbiota responsiveness to the prebiotic were demonstrated. This study demonstrates that media with different fermentable carbohydrate contents caused variability in gut microbiota responsiveness to an inulin-type fructan prebiotic; however, these results will need to be replicated in an in vivo study.

Microbiological analysis of acute infections of the nail fold on the basis of bait thread test.

IntroductionAn acute infection of the nail fold, called paronychia, is a common clinical problem. The basis for the implementation of the treatment is the result of microbiological examination. Due to the rapid and painful course of infection, usually an empirical antimicrobial treatment prior to obtaining microbiological test results is introduced.AimThe microbial analysis of acute infections of the nail fold.Material and methodsThe study included 32 tests conducted on 31 patients of the Department of Dermatology. Microbiological analysis was performed with the use of the so-called bait thread test.ResultsIn 73% of analyzed cases microbiological examination revealed mixed microbiological flora. Most cultured microorganisms were: Enterococcus faecalis (14%), Staphylococcus aureus (12%), Candida albicans (9%), Enterobacter cloacae (8%), and Klebsiella pneumoniae (7%). Most cultured bacteria belonged to the families or genera of Enterobacteriaceae (36%), other cultured bacteria were staphylococci (26%), enterococci (16%), Candida species (14%), and Gram-negative non-fermenting bacilli (8%).ConclusionsThe acute infection of the nail fold in the vast majority of cases is caused by mixed bacterial flora. A profile of isolated microorganisms suggests that the cause of the infection can be associated with neglect of hygiene. Fluoroquinolone and fusidic acid are recommended as the empirical therapy. Microbiological examination is the basis for the appropriate final treatment.

Carbapenemase-Producing Carbapenem-Resistant Enterobacteriaceae Among Patients Without Usual Risk Factors—Kentucky, 2016

Background On August 11, 2016, Hospital A notified Kentucky Department for Public Health of 2 carbapenemase-producing (CP) carbapenem-resistant Enterobacteriaceae (CRE) identified from clinical cultures from patients without CRE risk factors, including limited prior health care exposure and short hospitalizations. This hospital had no previously reported CRE infections. We investigated to identify and provide recommendations on patient exposures, additional cases, and environmental reservoirs.Methods A case was defined as any CRE culture collected at Hospital A January 1–December 12, 2016. Case finding was conducted by using laboratory records and screening cultures of patients. Patient exposures were identified through medical chart abstraction, patient interviews, and environmental sampling.ResultsIn addition to 2 initial cases, 21 additional cases were identified. Three Enterobacteriaceae genera (Klebsiella pneumoniae [17], Escherichia coli [5], and Enterobacter cloacae [1]) and 2 carbapenemases were identified. Sixteen of 21 admitted patients (76%) were CRE positive <7 days after admission; 11 (69%) were pulsed-field gel electrophoresis matched to another CRE, had prior negative screening culture, or no health care exposure during the past year. Thirteen patients were interviewed; 5 (38%) had traveled regionally outside Kentucky or to large Kentucky cities for health care. Environmental sampling identified evidence of carbapenemase on an environmental services (EVS) cart and in an EVS drain.Conclusion The CP-CRE outbreak was likely attributable to both importation and rapid in-facility transmission. Carbapenemase presence on EVS equipment indicates a role in health care CRE transmission. Additionally, regional travel for health care was identified as a potential CRE exposure in low-prevalence areas. Recommendations included routine disinfection of EVS equipment and addition of regional travel for health care to the facility’s patients at high-risk surveillance questionnaire.Disclosures All authors: No reported disclosures.

The locus of heat resistance (LHR) mediates heat resistance in Salmonella enterica, Escherichia coli and Enterobacter cloacae

Enterobacteriaceae comprise food spoilage organisms as well as food-borne pathogens including Escherichia coli. Heat resistance in E. coli was attributed to a genomic island called the locus of heat resistance (LHR). This genomic island is also present in several other genera of Enterobacteriaceae, but its function in the enteric pathogens Salmonella enterica and Enterobacter cloacae is unknown. This study aimed to determine the frequency of the LHR in food isolates of E. coli, and its influence on heat resistance in S. enterica and Enterobacter spp. Cell counts of LHR-positive strains of E. coli, S. enterica and E. cloacae were reduced by less than 1, 1, and 4 log (cfu/mL), respectively, after exposure to 60 °C for 5 min, while cell counts of LHR-negative strains of the same species were reduced by more than 7 log (cfu/mL). Introducing an exogenous copy of the LHR into heat-sensitive enteropathogenic E. coli and S. enterica increased heat resistance to a level that was comparable to LHR-positive wild type strains. Cell counts of LHR-positive S. enterica were reduced by less than 1 log(cfu/mL) after heating to 60 °C for 5 min. Survival of LHR-positive strains was improved by increasing the NaCl concentration from 0 to 4%. Cell counts of LHR-positive strains of E. coli and S. enterica were reduced by less than 2 log (cfu/g) in ground beef patties cooked to an internal core temperature of 71 °C. This study indicates that LHR-positive Enterobacteriaceae pose a risk to food safety.

Symbiont Diversity of Aphis (Toxoptera) citricidus (Hemiptera: Aphididae) as Influenced by Host Plants.

Aphids are well known for their association with endosymbiont bacteria. Almost all aphids harbor Buchnera aphidicola as an obligate symbiont and several other bacteria as facultative symbionts. Associations of facultative symbionts and aphids are quite variable in terms of diversity and prevalence across aphid species. Facultative symbionts can have a major impact on aphid bioecological traits. A number of factors shape the outcome of the facultative symbiont-aphid association, including aphid clone, bacterial genotype, geography, and host plant association. The effects of host plant on aphid-facultative symbiont associations are the least understood. We performed deep sequencing of the bacterial community associated with field populations of the oligophagous aphid Aphis (Toxoptera) citricidus collected from different host plants. We demonstrate that (i) A. citricidus has low symbiont diversity, (ii) symbiont diversity is affected by host plant, and (iii) host plants affect the relative abundance of the obligate symbiont Buchnera and an unknown genus of Enterobacteriaceae.

Galleria mellonella as a model system to assess the efficacy of antimicrobial agents against Klebsiella pneumoniae infection

Klebsiella pneumoniae, a rod-shaped Gram-negative bacterium, is the most significant member of the Klebsiella genus of Enterobacteriaceae. This Gram-negative opportunistic pathogen is responsible f...

Multiplex real-time PCR assay for the detection of extended-spectrum β-lactamase and carbapenemase genes using melting curve analysis

Real-time PCR melt curve assays for the detection of β-lactamase, extended-spectrum β-lactamase and carbapenemase genes in Gram-negative bacteria were developed. Two multiplex real-time PCR melt curve assays were developed for the detection of ten common β-lactamase genes: blaKPC-like, blaOXA-48-like, blaNDM-like, blaVIM-like, blaIMP-like, blaCTX-M-1+2-group, blaCMY-like, blaACC-like, blaSHV-like and blaTEM-like. The assays were evaluated using 25 bacterial strains and 31 DNA samples (total n=56) comprising different Enterobacteriaceae genera and Pseudomonas spp. These strains were previously characterized at five research institutes. Each resistance gene targeted in this study generated a non-overlapping and distinct melt curve peak. The assay worked effectively and detected the presence of additional resistance genes in 23 samples. The assays developed in this study offer a simple, low cost method for the detection of prevalent β-lactamase, ESBL and carbapenemase genes among Gram-negative pathogens.

Influence of the Biliary System on Biliary Bacteria Revealed by Bacterial Communities of the Human Biliary and Upper Digestive Tracts.

Biliary bacteria have been implicated in gallstone pathogenesis, though a clear understanding of their composition and source is lacking. Moreover, the effects of the biliary environment, which is known to be generally hostile to most bacteria, on biliary bacteria are unclear. Here, we investigated the bacterial communities of the biliary tract, duodenum, stomach, and oral cavity from six gallstone patients by using 16S rRNA amplicon sequencing. We found that all observed biliary bacteria were detectable in the upper digestive tract. The biliary microbiota had a comparatively higher similarity with the duodenal microbiota, versus those of the other regions, but with a reduced diversity. Although the majority of identified bacteria were greatly diminished in bile samples, three Enterobacteriaceae genera (Escherichia, Klebsiella, and an unclassified genus) and Pyramidobacter were abundant in bile. Predictive functional analysis indicated enhanced abilities of environmental information processing and cell motility of biliary bacteria. Our study provides evidence for the potential source of biliary bacteria, and illustrates the influence of the biliary system on biliary bacterial communities.

Composition, Diversity and Abundance of Gut Microbiome in Prediabetes and Type 2 Diabetes.

Association between type 2 diabetes (T2DM) and compositional changes in the gut micro biota is established, however little is known about the dysbiosis in early stages of Prediabetes (preDM). The purpose of this investigation is to elucidate the characteristics of the gut micro biome in preDM and T2DM, compared to Non-Diabetic (nonDM) subjects.Forty nine subjects were recruited for this study, 15 nonDM, 20 preDM and 14 T2DM. Bacterial community composition and diversity were investigated in fecal DNA samples using Illumina sequencing of the V4 region within the 16S rRNA gene.The five most abundant phyla identified were: Bacteroidetes, Firmicutes, Proteobacteria, Verrucomicrobia, and Actinobacteria. Class Chloracido bacteria was increased in preDM compared to T2DM (p = 0.04). An unknown genus from family Pseudonocardiaceae was significantly present in preDM group compared to the others (p = 0.04). Genus Collinsella, and an unknown genus belonging to family Enterobacteriaceae were both found to be significantly increased in T2DM compared to the other groups (Collinsella, and p = 0.03, Enterobacteriaceae genus p = 0.02). PERMANOVA and Mantel tests performed did not reveal a relationship between overall composition and diagnosis group or HbA1C level.This study identified dysbiosis associated with both preDM and T2DM, specifically at the class and genus levels suggesting that earlier treatment in preDM could possibly have an impact on the intestinal micro flora transitioning to T2DM.

Ceftazidime-avibactam activity when tested against ceftazidime-nonsusceptible Citrobacter spp., Enterobacter spp., Serratia marcescens, and Pseudomonas aeruginosa from Unites States medical centers (2011–2014)

A total of 6910 Enterobacteriaceae with inducible AmpC β-lactamases and 5328 Pseudomonas aeruginosa were collected from 71 US hospitals in 2011–2014 and were susceptibility tested using the reference broth microdilution method. Ceftazidime-avibactam demonstrated potent in vitro activity against all 3 Enterobacteriaceae genus groups evaluated, with MIC50/MIC90 values of 0.12/0.5μg/mL for Enterobacter spp. and Serratia marcescens and 0.12/0.25μg/mL for Citrobacter spp. (99.8–99.9% susceptibility rates at ≤8μg/mL). Furthermore, 99.3% of ceftazidime-nonsusceptible Enterobacteriaceae isolates (1015 of 1022) were susceptible to ceftazidime-avibactam (MIC50/MIC90 of 0.25–0.5/1–2μg/mL), whereas susceptibility rates for cefepime ranged from 45.9% (Citrobacter spp.) to 80.0% (S. marcescens). Ceftazidime-avibactam was also very active against P. aeruginosa (MIC50/MIC90, 2/4μg/mL; 96.8% inhibited at ≤8μg/mL). P. aeruginosa susceptibility rates to other antipseudomonal β-lactams ranged from 79.6% for piperacillin-tazobactam to 84.5% for cefepime. Ceftazidime-avibactam inhibited 67.4% of isolates at ≤8μg/mL (MIC50/MIC90, 8/32μg/mL) that were nonsusceptible to ceftazidime, cefepime, piperacillin-tazobactam, and meropenem.