Classification, identification, and clinical significance of Proteus, Providencia, and Morganella

Maternal vitamin D status during pregnancy and infant's gut microbiota: a prospective cohort study

Objectives

To prospectively explore the association of maternal serum 25(OH)D levels with the infant's gut microbiota in Chinese populations, and to evaluate its potential influence on the dynamic change patterns of offspring's gut microbiota from 1 to 6 months old.

Methods

Eighty-seven mother-infant dyads (vitamin D insufficient group vs. normal group = 59 vs. 28) were included in this longitudinal study. Two fecal samples were collected for the included infant at home by the parents at 1 month of age ("M1 phase") and 6 months of age ("M6 phase"). Gut microbiota were profiled by 16S rRNA gene sequencing. We performed mixed effects models on alpha diversity metrics, PERMANOVA tests on beta diversity distances, and linear discriminant analysis (LDA) to identify differently abundant taxa.

Results

We observed significantly lower Pielou's evenness and Shannon diversity in the vitamin D insufficient group in the M6 phase (p = 0.049 and 0.015, respectively), but not in the M1 phase (p > 0.05), and the dynamic changes in alpha diversity from 1 to 6 months old were significantly different according to maternal vitamin D status (p < 0.05). There were also significant differences in gut microbiota composition between the vitamin D insufficient group and normal group, both in the M1 and M6 phases (LDA score > 2.0, p < 0.05). Moreover, among the predicted metagenome functions, pathways related to amino acid biosynthesis, starch degradation, and purine nucleotides biosynthesis were enriched in the vitamin D insufficient group.

Conclusion

Our findings highlight that maternal vitamin D status plays a pivotal role in shaping the early-life gut microbiota of the next generation.

Snakebite-Associated Infections: A Systematic Review and Meta-Analysis

Snakebites still constitute a significant public health problem in developing countries and are considered a neglected tropical condition by the WHO. Snake accidents are associated with substantial morbidity and mortality and may produce secondary complications, such as severe infections. The objective of this systematic review was to determine the prevalence of snakebite infections and characterize the bacteria isolated from these infections. A systematic literature review in five databases was carried out to assess the prevalence of snakebite infection. A meta-analysis was performed using a random-effects model to calculate the pooled prevalence and 95% CIs. Cochran's Q test and the I2 statistic were used to assess between-study heterogeneity. The pooled prevalence of infection due to snakebite was 27.0% (95% CI: 22.0-32.0%), with high heterogeneity among studies (I2 = 99.7%). The prevalence was higher in Asia (32%) than in the Americas (21%). Snakebite infections required surgical interventions in 68% (95% CI: 37.0-98.0%). The leading group of pathogens identified corresponded to Gram-negative bacteria (63%), particularly Morganella morganii (32%), but also, Gram-positive cocci (40%), especially Enterococcus spp. (23%) and Staphylococcus aureus (15%). However, multiple other pathogens, including anaerobes, were found. A high prevalence of snakebite-associated infection has been described, primarily due to M. morganii, with the corresponding implications for empirical therapy. Rational use of antimicrobials is recommended, and this should guide initial empirical treatment. Moreover, isolation and identification of the possible bacteria present in snakebite wounds is recommended in all cases to confirm or rule out associated infection.

Calcium-sensing receptor alleviates gut damage caused by endotoxemia by regulating gut microbiota

Background

Growing evidence points to an association between the gut microbiota and neonatal diseases. Calcium-sensing receptor (CaSR) is a major modulator of tissue responses associated with calcium homeostasis and is highly expressed in the mammalian gut. CaSR may affect the composition and balance of the intestinal microenvironment.

Methods

Neonatal rats were randomized to the control, lipopolysaccharide (LPS), CaSR agonist, and CaSR inhibitor groups. The intestinal contents of neonatal rats were collected within 24 hours or 7 days after intervention. Then, 16S rRNA short amplicon sequencing was used to analyze biological information and the richness and diversity of individual taxa.

Results

LPS aggravated intestinal injury. The CaSR agonist alleviated injury, and the inhibitor further enhance intestinal injury. Activation of CaSR enhanced the diversity of the gut microbiota and the abundance of Lactobacillus. The lowest abundance of Firmicutes and the highest abundance of Bacteroidetes were found in the agonist group. CaSR impacted the bacterial species in rats with endotoxemia, and Akkermansia had the greatest effect on the differences among groups.

Conclusions

Activation of CaSRs could enhance the species richness and β-diversity of the gut microbiota and alter the abundance of many taxa. This could attenuate LPS-induced gut injury by modulating the gut microbiota.

Antimicrobial Susceptibility Trends of Proteeae Isolates From a Tertiary-Care Hospital in Western Saudi Arabia

BACKGROUND

The tribe Proteeae comprises Proteus, Providencia, and Morganella species. TheseGram-negative rods are of concern in that they are involved in diverse human infections, particularly in hospital settings. In the last two decades, there has been a sharp increase in infections by multidrug-resistant (MDR) Proteeae. Therefore, the objectives of this study were to: (i) assess the prevalence of infections caused by tribe Proteeae, (ii)determine the antimicrobial susceptibility profile of the test isolates, and (iii) identify the underlying risk factors for acquisition of infection by MDR strains.

METHODS

During the period from January 2019 to December 2020, we conducted a retrospective review of the electronic medical and laboratory records of adult patients who received care at our institution. In addition, we analyzed the risk factors associated with acquisition of infections by members of the tribe Proteeae using univariate and multivariate regression models.

RESULTS

Overall 403 adult patients (average age 59.69 ± 20.33 years) were enrolled into this study (196 males; 48.6%, and 207 females; 51.4%). Proteus mirabilis was the leading pathogen (70.7%; n=285), followed by Morganella morganii (20.1%; n=81), and Providencia species (9.2%; n=37). Most of the isolates were recovered from urine (59.3%; n=239), followed by wound swabs (23.1%; n=93), with the least from blood samples (1.7%; n=7). Out of 403 Proteeae isolates, 27.3% (n=110) were found to be extended-spectrum β-lactamase (ESBL)-producers, whereas 18.4% (n=74) were MDR. Patient's age, concomitant diabetes mellitus (DM), and long hospital stays were independently associated with infection by MDR strains.

CONCLUSION

Infections by MDR Proteeae are leading causes for morbidity in our tertiary-care facility. Strict adherence to infection control precautions, as well as effective implementation of antimicrobial stewardship programs, are crucial to overcome these superbugs.

Bacterial culture and susceptibility of samples taken from septic foot lesions of adult beef cattle

BACKGROUND

Lameness is an economically important and common disease of cattle, and foot disease is the most common cause of lameness in cattle. Limited data is available regarding lameness in cow-calf operations.

OBJECTIVES

Describe the bacteria most commonly isolated from septic lesions of the feet of adult beef cattle and the antimicrobial susceptibility patterns of the isolated bacteria.

ANIMALS

Fifty-four adult cattle from cow-calf operations and diagnosed with a sole abscess or distal interphalangeal joint sepsis were enrolled.

METHODS

Prospective observational study. Abscess fluid from a convenience sample of clinical cases was cultured. Isolated bacteria were identified using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry or 16s rRNA gene sequencing. Antimicrobial susceptibility profiling was performed on isolates when a bacterial species was identified from ≥5 samples.

RESULTS

Fifty of the 54 samples were polymicrobial. Trueperella pyogenes (22/54), Streptococcus uberis (16/54), and Bacteroides pyogenes (14/54) were the most commonly isolated bacteria. Eighty-one of 96 tested isolates were resistant to at least 1 antimicrobial; multidrug resistance was identified in 37/96 isolates. Oxytetracycline (50/96), tylosin (40/96), and florfenicol (37/96) resistance was commonly identified. Resistance to ceftiofur (5/96) was rare.

CONCLUSIONS AND CLINICAL IMPORTANCE

Septic processes of the foot in these adult beef cattle frequently were polymicrobial. Most of the isolated bacteria were resistant to at least 1 antimicrobial with over one-third being multidrug resistant. Although simple sole abscesses do not require antimicrobial treatment, deep septic processes of the foot often are treated with antimicrobials. Culture and susceptibility of deep septic lesions may guide judicious antimicrobial usage.

Development of the degradation bacteria in household food waste and analysis of the microbial community in aerobic composting

By screening the strains and testing different combinations of diverse bacteria, we developed a compound bacteria agent composing of 5 g Bacillus amyloliquefacien (B2), 10 g Pseudomonas aeruginosa (F4), 5 g Paenibacillus lautus (303), and 10 mL composite strains (DOD) for the degradation of household food waste (HFW). The final mass loss of HFW in aerobic composting with the compound bacteria agent B2+F4+303+DOD (group C) was 84.52%, increased by 20.83% over that loss in natural composting (group A). Analysis of 16S rRNA high-throughput sequencing showed that the phyla in the group A and the group C mainly included Firmicutes, Proteobacteria and Cyanobacteria. At the genus level, Pediococcus was the dominant genus in the group A, of which the microbial community performed better to maintain microbial system stable in the later stage of composting, while Weissella accounted for a larger proportion of the group C that acted well in reducing final mass of composting. The Ochrobactrum was closely related to the removal of odours in the early stage of the group C. The relative abundance of compound bacteria agent was always at a rather low level, suggested that it affected the composting process by changing the proportion of dominant bacteria in the compost. This article is protected by copyright. All rights reserved.

Intestinal homeostasis and inflammation: gut microbiota at the crossroads of pancreas-intestinal barrier axis

The pancreas contains exocrine glands, which release enzymes (e.g., amylase, trypsin, and lipase) that are important for digestion and islets, which produce hormones. Digestive enzymes and hormones are secreted from the pancreas into the duodenum and bloodstream, respectively. Growing evidence suggests that the roles of the pancreas extend to not only the secretion of digestive enzymes and hormones but also to the regulation of intestinal homeostasis and inflammation (e.g., mucosal defense to pathogens and pathobionts). Organ crosstalk between the pancreas and intestine is linked to a range of physiological, immunological, and pathological activities, such as the regulation of the gut microbiota by the pancreatic proteins and lipids, the retroaction of the gut microbiota on the pancreas, the relationship between inflammatory bowel disease, and pancreatic diseases. We herein discuss the current understanding of the pancreas–intestinal barrier axis and the control of commensal bacteria in intestinal inflammation.

Synergistic Antibacterial Activity of 1-Methyl Ester-Nigericin and Methyl 5-(Hydroxymethyl) Furan-2-Carboxylate Against Proteus spp

&lt;b&gt;Background and Objective:&lt;/b&gt; Synergistic combinations of antimicrobial agents with different mechanisms of action are successful approaches for combating bacterial infections. This study aimed to evaluate the synergistic effect of 1-methyl ester-nigericin &lt;b&gt;(1)&lt;/b&gt; and methyl 5-(hydroxymethyl) furan-2-carboxylate &lt;b&gt;(2)&lt;/b&gt; against &lt;i&gt;Proteus&lt;/i&gt; spp., isolates. &lt;b&gt;Materials and Methods:&lt;/b&gt; The synergistic antimicrobial activity of the compounds was tested by the checkerboard method and time-kill curves. To estimate the interaction between the compounds, the Fractional Inhibitory Concentration Index (FICI) of the combination was calculated. The cytotoxic activity of the compounds in combination was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay on LLC-MK2 cell lines. The reduction percentage of biofilms was obtained using the colourimetric method. &lt;b&gt;Results:&lt;/b&gt; The MIC values for compounds &lt;b&gt;1&lt;/b&gt; and &lt;b&gt;2&lt;/b&gt; against test bacteria ranged from 39.06-78.12 μg mL&lt;sup&gt;1&lt;/sup&gt; and from 78.12-156.25 μg mL&lt;sup&gt;1&lt;/sup&gt;, respectively. The MIC was reduced to 1-8th as a result of the combination of compounds &lt;b&gt;1&lt;/b&gt; and &lt;b&gt;2&lt;/b&gt;. After 4-24 hrs of treatment with ½ MIC of compounds &lt;b&gt;1&lt;/b&gt; and &lt;b&gt;2&lt;/b&gt;, the killing rate (in CFU mL&lt;sup&gt;1&lt;/sup&gt;) increased to a greater degree than observed with either test compound alone. The combination of compounds &lt;b&gt;1&lt;/b&gt; and &lt;b&gt;2&lt;/b&gt; showed a synergistic effect with FICI of 0.50 and 0.28. The synergistic combination of compounds &lt;b&gt;1&lt;/b&gt; and &lt;b&gt;2&lt;/b&gt; was effective on the biofilm reduction of &lt;i&gt;Proteus&lt;/i&gt; &lt;i&gt;vulgaris&lt;/i&gt; NP16 (85.72%) and NP47 (89.14%). &lt;b&gt;Conclusion:&lt;/b&gt; This study recommends compounds &lt;b&gt;1&lt;/b&gt; and &lt;b&gt;2&lt;/b&gt; in combination as a potential alternative treatment agent for &lt;i&gt;Proteus&lt;/i&gt; spp. infections.

Fast Identification and Quantification of Uropathogenic E. coli through Cluster Analysis

Rapid diagnostic tools to detect, identify, and enumerate bacteria are key to maintaining effective antibiotic stewardship and avoiding the unnecessary prescription of broad-spectrum agents. In this study, a 15 min agglutination assay is developed that relies on the use of mannose-functionalized polymeric microspheres in combination with cluster analysis. This allows for the identification and enumeration of laboratory (BW25113), clinical isolate (NCTC 12241), and uropathogenic Escherichia coli strains (NCTC 9001, NCTC 13958, J96, and CFT073) at clinically relevant concentrations in tryptic soy broth (10³-10⁸ CFU/mL) and in urine (10⁵-10⁸ CFU/mL). This fast, simple, and efficient assay offers a step forward toward efficient point-of-care diagnostics for common urinary tract infections.

Providencia heimbachae Associated with Post-weaning Diarrhea in Piglets: Identification, Phenotype, and Pathogenesis

Despites Providencia heimbachae has been isolated from human, penguin, and bovine fetus, relatively little information is available regarding the pathogenicity and biologic characteristics of P. heimbachae. Here, we report that investigation of post-weaning diarrhea yielded bacterial isolates identified as P. heimbachae based on the biochemical tests and 16S ribosomal DNA sequence analysis. The two isolates were positive for utilization of Malonate, no gas production from glucose, and non-fermentation of D-mannitol, D-Galactose, and L-Rhamnose that were different from those of the type strain, and both of them have the ability of adhesion and invasion to IPEC-J2 cells, and were resistant to 21 out of the 41 antibiotics tested. In addition, the isolate 99101 was highly pathogenic to mice and piglets. Histopathology studies on nerve tissue of piglets that developed hindlimb paralysis showed microglia cell infiltration and neuron damage in the spinal cord. Notably, the strains could grow under low temperature (4 °C), which raise attention of a new risk factor for food safety. To the best of our knowledge, this is the first report of P. heimbachae strain caused post-weaning diarrhea in piglets in both natural and experimental conditions. These findings extended the knowledge of P. heimbachae as an important zoonotic agent, which should be given more attention during surveillance and diagnostics.

Genomic analysis of the nomenclatural type strain of the nematode-associated entomopathogenic bacterium Providencia vermicola

Background

Enterobacteria of the genus Providencia are mainly known as opportunistic human pathogens but have been isolated from highly diverse natural environments. The species Providencia vermicola comprises insect pathogenic bacteria carried by entomoparasitic nematodes and is investigated as a possible insect biocontrol agent. The recent publication of several genome sequences from bacteria assigned to this species has given rise to inconsistent preliminary results.

Results

The genome of the nematode-derived P. vermicola type strain DSM_17385 has been assembled into a 4.2 Mb sequence comprising 5 scaffolds and 13 contigs. A total of 3969 protein-encoding genes were identified. Multilocus sequence typing with different marker sets revealed that none of the previously published presumed P. vermicola genomes represents this taxonomic species. Comparative genomic analysis has confirmed a close phylogenetic relationship of P. vermicola to the P. rettgeri species complex. P. vermicola DSM_17385 carries a type III secretion system (T3SS-1) with probable function in host cell invasion or intracellular survival. Potentially antibiotic resistance-associated genes comprising numerous efflux pumps and point-mutated house-keeping genes, have been identified across the P. vermicola genome. A single small (3.7 kb) plasmid identified, pPVER1, structurally belongs to the qnrD-type family of fluoroquinolone resistance conferring plasmids that is prominent in Providencia and Proteus bacteria, but lacks the qnrD resistance gene.

Conclusions

The sequence reported represents the first well-supported published genome for the taxonomic species P. vermicola to be used as reference in further comparative genomics studies on Providencia bacteria. Due to a striking difference in the type of injectisome encoded by the respective genomes, P. vermicola might operate a fundamentally different mechanism of entomopathogenicity when compared to insect-pathogenic Providencia sneebia or Providencia burhodogranariea. The complete absence of antibiotic resistance gene carrying plasmids or mobile genetic elements as those causing multi drug resistance phenomena in clinical Providencia strains, is consistent with the invertebrate pathogen P. vermicola being in its natural environment efficiently excluded from the propagation routes of multidrug resistance (MDR) carrying genetic elements operating between human pathogens. Susceptibility to MDR plasmid acquisition will likely become a major criterion in the evaluation of P. vermicola for potential applications in biological pest control.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-08027-w.

Diversity in the swimming motility and flagellar regulon structure of uropathogenic Morganella morganii strains

In current times, the opportunistic pathogen Morganella morganii is increasingly becoming a cause of urinary tract infections. The condition has been further complicated by the multiple drug resistance of most isolates. Swimming motility plays an important role in the development of urinary tract infections, allowing bacteria to colonize the upper urinary tract. We determined the differences between the growth, swimming motility, and biofilm formation of two M. morganii strains MM 1 and MM 190 isolated from the urine of patients who had community-acquired urinary tract infections. MM 190 showed a lower growth rate but better-formed biofilms in comparison to MM 1. In addition, MM 190 possessed autoaggregation abilities. It was found that a high temperature (37 °C) inhibits the flagellation of strains and makes MM 190 less motile. At the same time, the MM 1 strain maintained its rate of motility at this temperature. We demonstrated that urea at a concentration of 1.5% suppresses the growth and swimming motility of both strains. Genome analysis showed that MM 1 has a 17.7-kb-long insertion in flagellar regulon between fliE and glycosyltransferase genes, which was not identified in corresponding loci of MM 190 and 9 other M. morganii strains with whole genomes. Both strains carry two genes encoding flagellin, which may indicate flagellar antigen phase variation. However, the fliC2 genes have only 91% identity to each other and exhibit some variability in the regulatory region. We assume that all these differences influence the swimming motility of the strains.

Dysbiosis in Metabolic Genes of the Gut Microbiomes of Patients with an Ileo-anal Pouch Resembles That Observed in Crohn's Disease

Crohn's disease (CD), ulcerative colitis (UC), and pouchitis are multifactorial and chronic inflammatory bowel diseases (IBD). Pouchitis develops in former UC patients after proctocolectomy and ileal-pouch-anal anastomosis and is characterized by inflammation of the previously normal small intestine comprising the pouch. The extent to which microbial functional alteration (dysbiosis) in pouchitis resembles that of CD or UC has not been investigated, and the pathogenesis of pouchitis remains unknown. We collected 208 fecal metagenomes from 69 patients with a pouch (normal pouch and pouchitis) and compared them to publicly available metagenomes of patients with CD (n = 88), patients with UC (n = 76), and healthy controls (n = 56). Patients with pouchitis presented the highest alterations in species, metabolic pathways, and enzymes, which was correlated with intestinal inflammation. Ruminococcus gnavus strains encoding mucin-degrading glycoside hydrolases were highly enriched in pouchitis. Butyrate and secondary bile acid biosynthesis pathways were decreased in IBD phenotypes and were especially low in pouchitis. Pathways such as amino acid biosynthesis and degradation of aromatic compounds and sugars, encoded by members of the Enterobacteriaceae, were enriched in pouch and CD but not in UC. We developed microbial feature-based classifiers that can distinguish between patients with a normal pouch and pouchitis and identified species and genes that were predictive of pouchitis. We propose that the noninflamed pouch is already dysbiotic and microbially is similar to CD. Our study reveals microbial functions that outline the pathogenesis of pouchitis and suggests bacterial groups and functions that could be targeted for intervention to attenuate small intestinal inflammation present in pouchitis and CD.

IMPORTANCE Crohn's disease (CD), ulcerative colitis (UC), and pouchitis are chronic inflammatory conditions of the bowel. Pouchitis develops in former UC patients after proctocolectomy and ileal-pouch-anal anastomosis and is characterized by inflammation of the previously normal small intestine comprising the pouch. The extent to which microbial dysbiosis in patients with pouchitis resembles that of CD or UC and the pathogenesis of pouchitis remains unclear. We investigated the functions in the gut microbiomes of these patients using metagenomics. We found that the noninflamed pouch is already dysbiotic and microbially is similar to CD. Our study reveals microbial functions with a potential role in pouchitis pathogenesis such as depletion in butyrate and secondary bile acid synthesis and enrichment of amino acid synthesis and degradation of aromatic compounds, encoded by members of the Enterobacteriaceae. We developed microbial feature-based classifiers that can distinguish between patients with a normal pouch and pouchitis and identified species and genes that were predictive of pouchitis. We suggest species and functions that could be targeted for intervention to attenuate small intestinal inflammation present in pouchitis and CD.

Exemplifying an archetypal thorium-EPS complexation by novel thoriotolerant Providencia thoriotolerans AM3

It is the acquisition of unique traits that adds to the enigma of microbial capabilities to carry out extraordinary processes. One such ecosystem is the soil exposed to radionuclides, in the vicinity of atomic power stations. With the aim to study thorium (Th) tolerance in the indigenous bacteria of such soil, the bacteria were isolated and screened for maximum thorium tolerance. Out of all, only one strain AM3, found to tolerate extraordinary levels of Th (1500 mg L⁻¹), was identified to be belonging to genus Providencia and showed maximum genetic similarity with the type strain P. vermicola OP1T. This is the first report suggesting any bacteria to tolerate such high Th and we propose to term such microbes as ‘thoriotolerant’. The medium composition for cultivating AM3 was optimized using response surface methodology (RSM) which also led to an improvement in its Th-tolerance capabilities by 23%. AM3 was found to be a good producer of EPS and hence one component study was also employed for its optimization. Moreover, the EPS produced by the strain showed interaction with Th, which was deduced by Fourier Transform Infrared (FTIR) spectroscopy.

Genomic Analysis of SXT/R391 Integrative Conjugative Elements From Proteus mirabilis Isolated in Brazil

Integrative conjugative elements (ICEs) are widespread in many bacterial species, often carrying antibiotic resistance determinants. In the present work, we screened a collection of Proteus mirabilis clinical isolates for the presence of type 1 SXT/R391 ICEs. Among the 76 isolates analyzed, 5 of them carry such elements. The complete sequences of these elements were obtained. One of the isolates carried the CMY-2 beta-lactamase gene in a transposon and is nearly identical to the element ICEPmiJpn1 previously described in Japan, and later shown to be present in other parts of the world, indicating global spread of this element. Nevertheless, the Brazilian isolate carrying ICEPmiJpn1 is not clonally related to the other lineages carrying the same element around the world. The other ICEs identified in this work do not carry known antibiotic resistance markers and are diverse in variable gene content and size, suggesting that these elements may be responsible for the acquisition of other advantageous traits by bacteria. Some sequences carried by these elements in Brazilian strains were not previously found in other SXT/R391 variants.

Draft Genome Sequence of a New Delhi Metallo-β-Lactamase (NDM-1)-Producing Providencia stuartii Strain Isolated in Lima, Peru

Providencia stuartii is an opportunistic pathogen of the Enterobacteriales order. Here, we report the 4,594,658-bp draft genome sequence of a New Delhi metallo-β-lactamase (NDM-1)-producing Providencia stuartii strain that was isolated from an emergency patient in a private clinic in Lima, Peru.

Providencia stuartii is an opportunistic pathogen of the Enterobacteriales order. Here, we report the 4,594,658-bp draft genome sequence of a New Delhi metallo-β-lactamase (NDM-1)-producing Providencia stuartii strain that was isolated from an emergency patient in a private clinic in Lima, Peru.

Isolation and genomic characterization of a pathogenic Providencia rettgeri strain G0519 in turtle Trachemys scripta

Providencia rettgeri infection has occurred occasionally in aquaculture, but is rare in turtles. Here, a pathogenic P. rettgeri strain G0519 was isolated from a diseased slider turtle (Trachemys scripta) in China, and qPCR assay was established for the RTX toxin (rtxD) gene. Histopathological examination showed that many inflammatory cells were infiltrated into heart, liver and intestine, as well as the necrosis of liver, kidney and spleen. The genome consisted of one circular chromosome (4.493 Mb) and one plasmid (18.8 kb), and predicted to contain 4170 and 19 protein-coding genes, respectively. Multiple pathogenic and virulence factors (e.g., fimbria, adhesion, invasion, toxin, hemolysin, chemotaxis, secretion system), multidrug-resistant genes (e.g., ampC, per-1, oxa-1, sul1, tetR) and a novel genomic resistance island PRI519 were identified. Comparative genome analysis revealed the closest relationship was with P. rettgeri, and with P. heimbachae closer than with other Providencia spp. To our knowledge, this was first report on genomic characterization of multidrug-resistant pathogenic P. rettgeri in cultured turtles.

Antibacterial Activity of Endostemon tereticaulis (Poir.) M. Ashby Essential Oil and Ethanolic Extract Against Resistant Pathogenic Bacteria

Endostemon tereticaulis (poir.) M.Ashby is a species of the Lamiaceae family present in Niger. This plant is used in traditional medicine due to its various biological potentialities. The present study investigated the chemical composition of the essential oil and the antibacterial activity of the essential oil and ethanolic extract of Endostemon tereticaulis against resistant pathogenic bacteria. Gas chromatography-mass spectrometry analysis of the essential oil led to the identification of 43 compounds representing 99.55% of the total essential oil. The major components were caryophyllene oxide (15.17%) followed by α-humulene (13.96%), α-copaene (11.75%), ( E)-β-caryophyllene (8.44%), and δ-cadinene (6.78%). The antibacterial activity was tested against multiresistant Acinetobacter baumannii P1483, Salmonella spp. H1548, extended-spectrum β-lactamase- Escherichia coli Bu8566, Enterobacter cloacae Bu147, Proteus mirabilis Bu190 , Pseudomonas aeruginosa (ATCC 27853), Klebsiella pneumoniae (ATCC 700603), Escherichia coli (ATCC 25922), Enterococcus faecium H3434, methicillin-resistant Staphylococcus aureus P1123, and Staphylococcus aureus (ATCC 25923). The antibacterial assays revealed that the essential oil was more active than the ethanolic extract against the studied bacteria with minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values ranging from 0.06 to 2 mg/mL. Also, the ethanolic extract was effective against the bacteria tested with MIC and MBC values ranging from 0.12 to 3 mg/mL. This study showed that Endostemon tereticaulis essential oil is rich in bioactive compounds. Ethanolic extract and essential oil exhibited potential antibacterial activity. These results provide a scientific basis for the use of this plant in traditional medicine. The current study described for the first time the antibacterial activity of Endostemon tereticaulis.

The gut and feed residue microbiota changing during the rearing of Hermetia illucens larvae

Larvae of Hermetia illucens, commonly known as black soldier fly, efficiently convert organic waste into nutrient-rich supplements for different applications. Here we performed a preliminary experiment to investigate the dynamics of the H. illucens gut microbiota and changes in the composition of the bacterial community in the residue of the larval feed during rearing. We furthermore quantified the presence of antibiotic resistance and disinfectant genes in the gut and feed microbiota during the rearing process to elucidate if rearing leads to a reduction, increase, and/or transfer of resistance genes from the feed to larvae and vice versa. We found that the gut and feed residue bacterial communities were distinct throughout the rearing process. The gut microbiome remained more stable compared to the feed residue microbiome varying in both bacterial abundance and community structure during rearing. Antibiotic-resistance genes were present in both, gut and feed residues, with a significant increase in pupae and residue samples taken at the end of the rearing process. Disinfectant-resistance genes were present in the feed residue and even increased during the rearing process but were not transferred to the gut microbiome. We conclude that H. illucens larvae have a stable gut microbiome that does not change significantly over the course of larval development, whereas bacterial communities in the feed residue are strongly affected by rearing. If the presence of antibiotics and disinfectants during rearing, can promote the spread of antibiotic/disinfectant-resistance genes among feed and larvae needs to be evaluated in further experiments.

Characterization of a Novel Diarrheagenic Strain of Proteus mirabilis Associated With Food Poisoning in China

Proteus mirabilis is commonly considered to be an opportunistic pathogen causing urinary tract infections (UTIs) in humans. However, some strains of P. mirabilis were found to be associated with food poisoning outbreaks, with the pathogenic mechanism still unclear. In our study, we described a novel strain of P. mirabilis C02011 isolated from patients’ specimens in a food poisoning in China. In order to determine its gastrointestinal pathogenicity, experiments were performed to compare P. mirabilis B02005 strain (isolated from healthy people) and P. mirabilis American Type Culture Collection (ATCC) 29906 strain both in vitro [Caco-2 cells: bacterial adhesion and invasion assays, Giemsa staining, and transmission electron microscopy (TEM)] and in vivo [BALB/c mouse model: fecal character, colon injury, histological examination, immunochemistry, and western blotting (WB)]. According to the results, C02011 strain exhibited almost identical characteristics with B02005 strain in bacterial appearance and proliferation. In vitro, Caco-2 cells were infected with P. mirabilis C02011, B02005, and P. mirabilis ATCC 29906 strains. After that, Giemsa staining and TEM were used for observing the infection process of C02011 strain. Meanwhile, the adhesive abilities of different strains were rated as follows: P. mirabilis B02005 > P. mirabilis C02011 > P. mirabilis ATCC 29906 (P < 0.01). Invasive abilities of different strains were rated as follows: P. mirabilis C02011 > P. mirabilis B02005 > P. mirabilis ATCC 29906 (P < 0.01). In vivo, BALB/c mice were infected with P. mirabilis C02011 and B02005 strains. C02011 strain shows more virulence than B02005 strain in terms of the following indicators: (1) feces water content and fecal character; (2) colon length of mice; (3) histological examination on mouse intestine tissues; (4) ELISA for detecting TNF-α level in the colon; and (5) WB and immunohistochemistry (IHC) for detecting occludin protein expression in the colon. On the basis of these results, we firstly validated that the novel strain of P. mirabilis C02011 shows more gastrointestinal pathogenicity than the other strains isolated from a healthy individual. In addition, type IV secretion system (T4SS) was preliminarily confirmed to play an important role in the pathogenesis of diarrheal P. mirabilis isolated from the food poisoning incident.

Proanthocyanidin Interferes with Intrinsic Antibiotic Resistance Mechanisms of Gram-Negative Bacteria

Antibiotic resistance is spreading at an alarming rate among pathogenic bacteria in both medicine and agriculture. Interfering with the intrinsic resistance mechanisms displayed by pathogenic bacteria has the potential to make antibiotics more effective and decrease the spread of acquired antibiotic resistance. Here, it is demonstrated that cranberry proanthocyanidin (cPAC) prevents the evolution of resistance to tetracycline in Escherichia coli and Pseudomonas aeruginosa, rescues antibiotic efficacy against antibiotic-exposed cells, and represses biofilm formation. It is shown that cPAC has a potentiating effect, both in vitro and in vivo, on a broad range of antibiotic classes against pathogenic E. coli, Proteus mirabilis, and P. aeruginosa. Evidence that cPAC acts by repressing two antibiotic resistance mechanisms, selective membrane permeability and multidrug efflux pumps, is presented. Failure of cPAC to potentiate antibiotics against efflux pump-defective mutants demonstrates that efflux interference is essential for potentiation. The use of cPAC to potentiate antibiotics and mitigate the development of resistance could improve treatment outcomes and help combat the growing threat of antibiotic resistance.

Genome Sequence of Providencia rettgeri NVIT03, Isolated from Nasonia vitripennis

Providencia rettgeri is a common insect-associated Gram-negative bacterium. Here, we present the draft genome sequence of P. rettgeri NVIT03, the most common bacterial symbiont of the insect hymenopteran model Nasonia vitripennis. This symbiont is also part of the Sarcophaga bullata pupal microbiome that Nasonia spp. parasitize and that critically influences the development of the wasp.

F. A review on the development of urease inhibitors as antimicrobial agents against pathogenic bacteria

Ureases are enzymes that hydrolyze urea into ammonium and carbon dioxide. They have received considerable attention due to their impacts on living organism health, since the urease activity in microorganisms, particularly in bacteria, are potential causes and/or factors contributing to the persistence of some pathogen infections. This review compiles examples of the most potent antiurease organic substances. Emphasis was given to systematic screening studies on the inhibitory activity of rationally designed series of compounds with the corresponding SAR considerations. Ureases of Canavalia ensiformis, the usual model in antiureolytic studies, are emphasized. Although the active site of this class of hydrolases is conserved among bacteria and vegetal ureases, the same is not observerd for allosteric site. Therefore, inhibitors acting by participating in interactions with the allosteric site are more susceptible to a potential lack of association among their inhibitory profile for different ureases. The information about the inhibitory activity of different classes of compounds can be usefull to guide the development of new urease inhibitors that may be used in future in small molecular therapy against pathogenic bacteria.

Chemical Synthesis of Rare, Deoxy-Amino Sugars Containing Bacterial Glycoconjugates as Potential Vaccine Candidates

Bacteria often contain rare deoxy amino sugars which are absent in the host cells. This structural difference can be harnessed for the development of vaccines. Over the last fifteen years, remarkable progress has been made toward the development of novel and efficient protocols for obtaining the rare sugar building blocks and their stereoselective assembly to construct conjugation ready bacterial glycans. In this review, we discuss the total synthesis of a variety of rare sugar containing bacterial glycoconjugates which are potential vaccine candidates.

Nitric oxide-releasing microparticles as a potent antimicrobial therapeutic against chronic rhinosinusitis bacterial isolates

BACKGROUND

Bacteria, particularly in the biofilm state, may be implicated in the pathogenesis of chronic rhinosinusitis (CRS) and enhance antibiotic resistance. Nitric oxide (NO) is a gaseous immunomodulator with antimicrobial activity and a short half-life, complicating achievement of therapeutic concentrations. We hypothesized that a novel microparticle-based delivery platform, which allows for adjustable release of NO, could exhibit potent antibacterial effects.

METHODS

Porous organosilica microparticles (SNO-MP) containing nitrosylated thiol groups were formulated. Dissociation of the nitrosothiol groups generates NO at body temperature. The susceptibility of bacterial isolates from CRS patients to SNO-MP was evaluated through a colony forming unit (CFU) assay. Serial dilutions of SNO-MP in triplicate were incubated with isolates in suspension for 6 hours followed by plating on tryptic soy agar and overnight incubation followed by CFU quantification. Statistical analysis was performed with SPSS using one-way analysis of variance with Bonferroni correction.

RESULTS

SNO-MP displayed antibacterial activity against gram-positive (methicillin-resistant and -sensitive Staphylococcus aureus) and gram-negative (Pseudomonas aeruginosa, Enterobacter aerogenes, and Proteus mirabilis) isolates. SNO-MP induced dose-dependent reductions in CFU across all strains. Compared with controls and blank nanoparticles, SNO-MP (10 mg/mL) induced a 99.99%-100% reduction in CFU across all isolates, equivalent to a 5-9 log kill (p < 0.005). There was no statistically significant difference in CFU concentration between controls and blank microparticles.

CONCLUSION

SNO-MP demonstrates potent bactericidal effect against antibiotic-resistant CRS bacterial strains.

Proteus spp. as Putative Gastrointestinal Pathogens

Proteus species, members of the Enterobacteriaceae family, are usually considered commensals in the gut and are most commonly recognized clinically as a cause of urinary tract infections. However, the recent identification of Proteus spp. as potential pathogens in Crohn's disease recurrence after intestinal resection serves as a stimulus to examine their potential role as gut pathogens. Proteus species possess many virulence factors potentially relevant to gastrointestinal pathogenicity, including motility; adherence; the production of urease, hemolysins, and IgA proteases; and the ability to acquire antibiotic resistance. Gastrointestinal conditions that have been linked to Proteus include gastroenteritis (spontaneous and foodborne), nosocomial infections, appendicitis, colonization of devices such as nasogastric tubes, and Crohn's disease. The association of Proteus species with Crohn's disease was particularly strong. Proteus species are low-abundance commensals of the human gut that harbor significant pathogenic potential; further investigation is needed.

Evaluation of Providencia rettgeri pathogenicity against laboratory Mediterranean fruit fly strain (Ceratitis capitata)

The Mediterranean fruit fly (medfly) Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), is often referred to as the most severe agricultural pest. Its biological control is mainly through the Sterile Insect Technique (SIT). Colonization, mass-rearing conditions and the irradiation process impact the competitiveness of sterile males and disrupt symbiotic associations by favoring some bacterial species and suppressing others. Levels of Providencia species have been shown to fluctuate considerably in the gut of the medfly laboratory strain Vienna 8 under irradiation, increasing by up to 22%. This study aimed to determine the pathogenicity of Providencia rettgeri isolated from the gut of laboratory Vienna 8 medfly strains by examining the effects of 1) two different treatment doses on egg-hatching and development and 2) two infection methodologies (ingestion and injection) of male and female adults according to their mating status. Treatment of eggs with P. rettgeri (2%) significantly decreased the mean egg to pupae recovery rate. Our data showed significant high mortality in flies with both injection and ingestion after 24 hours without any effect of sex. Microbial counts demonstrated that the bacteria could proliferate and replicate in adult flies. There was a significant sex-dependent effect after infection, with mortality decreasing significantly for males more than females. Providencia rettgeri can be considered as a potential pathogen of C. capitata. Mating protected males and females against infection by P. rettgeri by triggering an immune response leading to double the levels of Cecropin being secreted compared to infected virgin adults, thus reducing the virulence of the bacteria.

Emergence of multidrug-resistant Providencia rettgeri isolates co-producing NDM-1 carbapenemase and PER-1 extended-spectrum β-lactamase causing a first outbreak in Korea

Background

Nosocomial outbreak due to carbapenem-resistant Enterobacteriaceae has become serious challenge to patient treatment and infection control. We describe an outbreak due to a multidrug-resistant Providencia rettgeri from January 2016 to January 2017 at a University Hospital in Seoul, Korea.

Methods

A total of eight non-duplicate P. rettgeri isolates were discovered from urine samples from eight patients having a urinary catheter and admitted in a surgical intensive care unit. The β-lactamase genes were identified using polymerase chain reaction and direct sequencing, and strain typing was done with pulsed-field gel electrophoresis (PFGE).

Results

All isolates showed high-level resistance to extended-spectrum cephalosporins, aztreonam, meropenem, ertapenem, ciprofloxacin, and amikacin. They harbored the bla_NDM-1 carbapenemase and the bla_PER-1 type extended-spectrum β-lactamases genes. PFGE revealed that all isolates from eight patients were closely related strains.

Conclusions

The 13-month outbreak ended following reinforcement of infection control measures, including contact isolation precautions and environmental disinfection. This is the first report of an outbreak of a P. rettgeri clinical isolates co-producing NDM-1 and PER-1 β-lactamase.

Proteus alimentorum sp. nov., isolated from pork and lobster in Ma'anshan city, China

Two strains of Gram-stain-negative, facultatively anaerobic short-rod bacteria were recovered from two different food samples in Ma'anshan city, Anhui province, China in 2008. The bacteria were characterized in a polyphasic taxonomic study that included phenotypic, phylogenetic and genotypic methodologies. Phylogenetic analysis of the 16S rRNA gene demonstrated that the two strains belonged to the genus Proteus and were most similar to Proteus vulgaris ATCC 29905^T with a score of 99.7 %. Phylogenetic analysis of the rpoB gene placed the two strains into a cluster with a distinctly interspecies phylogenetic branch that was clearly separated from six type strains of the genus Proteus, with the most closely related species being Proteus mirabilis ATCC 29906^T. In silico genomic comparisons, including in silico DNA-DNA hybridization (isDDH) and average nucleotide identity (ANI) analysis showed that the representative strain, 08MAS0041^T, and all six Proteus species share less than 70 % isDDH and have a 95 % ANI cutoff level, supporting the designation of the two strains as a novel species of the genus Proteus. The predominant cellular fatty acids of strain 08MAS0041^T were C16 : 0 (24.8 %), C16 : 1ω7c/16 : 1ω6c (16.5 %), C18 : 1ω6c/C18 : 1ω7c (14.5 %), C17 : 0 cyclo (12.6 %) and C16 : 1iso I/C14 : 0 3-OH (10.6 %). The analysis of biochemical, phylogenetic and genomic data confirmed that the two strains were clearly different from all recognized species of the genus Proteus and represent a novel Proteus species, for which the name Proteus alimentorum sp. nov. is proposed. The type strain is 08MAS0041^T (=DSM 104685^T=CGMCC 1.15939^T).

Characterization of multiple antibiotic resistance of culturable microorganisms and metagenomic analysis of total microbial diversity of marine fish sold in retail shops in Mumbai, India

Marine fish species were analyzed for culturable and total metagenomic microbial diversity, antibiotic resistance (AR) pattern, and horizontal gene transfer in culturable microorganisms. We observed a high AR microbial load of 3 to 4 log CFU g^-1. Many fish pathogens like Providencia, Staphylococcus, Klebsiella pneumoniae, Enterobacter, Vagococcus, and Aeromonas veronii were isolated. Photobacterium and Vibrio were two major fish and human pathogens which were identified in the fish metagenome. Other pathogens that were identified were Shewanella, Acinetobacter, Psychrobacter, and Flavobacterium. Most of these pathogens were resistant to multiple antibiotics such as erythromycin, kanamycin, neomycin, streptomycin, penicillin, cefotaxime, bacitracin, rifampicin, trimethoprim, ciprofloxacin, and doxycycline with a high multiple antibiotic resistance index of 0.54-0.77. The fish microflora showed high prevalence of AR genes like bla _TEM, Class I integron, tetA, aph(3')-IIIa, ermB, aadA, and sul1. Nineteen of 26 AR isolates harbored Class I integrons showing high co-resistance to trimethoprim, kanamycin, doxycycline, and cefotaxime. Mobile R-plasmids from 6 of the 12 AR pathogens were transferred to recipient E. coli after conjugation. The transconjugants harbored the same R-plasmid carrying bla _CTX-M, dfr1, tetA, bla _TEM, and cat genes. This study confirms that fish is a potential carrier of AR pathogens which can enter the human gut via food chain. To the best of our knowledge, this is the first study in the Indian subcontinent reporting a direct evidence of spread of AR pathogens to humans from specific marine fish consumption.

Successful treatment of Providencia rettgeri cholecystitis and neutrophilic cholangitis in a cat

Case summary

A 15-year-old male neutered domestic shorthair cat was presented with a recent history of seizures, diarrhoea, lethargy, fever and jaundice. Marked elevation of liver enzyme activity was present and ultrasound examination was suggestive of cholecystitis and hepatitis. Neutrophilic cholangitis was confirmed on histopathology of liver biopsies. Bile culture identified a monomicrobial infection with Providencia rettgeri, which was resistant to multiple antimicrobial agents. The cat was treated with oral pradofloxacin for 4 weeks and remained well 4 months later.

Relevance and novel information

Providencia species are rarely reported in the veterinary literature and are an uncommon cause of disease in humans. The significance of this species in humans relates to the high prevalence of antimicrobial resistance. This is the first report of P rettgeri causing clinical illness in a cat and highlights the importance of bile cultures in hepatic disease.

Changes in the lipopolysaccharide of Proteus mirabilis 9B-m (O11a) clinical strain in response to planktonic or biofilm type of growth

The impact of planktonic and biofilm lifestyles of the clinical isolate Proteus mirabilis 9B-m on its lipopolysaccharide (O-polysaccharide, core region, and lipid A) was evaluated. Proteus mirabilis bacteria are able to form biofilm and lipopolysaccharide is one of the factors involved in the biofilm formation. Lipopolysaccharide was isolated from planktonic and biofilm cells of the investigated strain and analyzed by SDS–PAGE with silver staining, Western blotting and ELISA, as well as NMR and matrix-assisted laser desorption ionization time-of-flight mass spectrometry techniques. Chemical and NMR spectroscopic analyses revealed that the structure of the O-polysaccharide of P. mirabilis 9B-m strain did not depend on the form of cell growth, but the full-length chains of the O-antigen were reduced when bacteria grew in biofilm. The study also revealed structural modifications of the core region in the lipopolysaccharide of biofilm-associated cells—peaks assigned to compounds absent in cells from the planktonic culture and not previously detected in any of the known Proteus core oligosaccharides. No differences in the lipid A structure were observed. In summary, our study demonstrated for the first time that changes in the lifestyle of P. mirabilis bacteria leads to the modifications of their important virulence factor—lipopolysaccharide.

Proteus columbae sp. nov., isolated from a pigeon in Ma'anshan, China

A Gram-negative, facultatively anaerobic bacillus, strain 08MAS2615^T, was isolated from the flesh of a pigeon specimen collected in Ma'anshan, Anhui province, China. Phylogenetic analysis of 16S rRNA gene sequences confirmed that strain 08MAS2615^T belonged to the genus Proteus, and formed an independent branch which was clearly separated from the other six known species of Proteus. Strain 08MAS2615^T was more closely related to Proteus vulgaris ATCC 29905^T and Proteus penneri NCTC 12737^T than other Proteus species. Similar independent phylogenetic results were obtained using rpoB gene sequence analysis, whereas strain 08MAS2615^T clustered near the species of Proteus cibarius JS9^T and Proteus terrae N5/687^T. Furthermore, the genome-wide core-single nucleotide polymorphism-based phylogenetic tree confirmed that strain 08MAS2615^T formed a monophyletic and robust clade. Based on whole-genome sequences, the range of in silico DNA-DNA hybridization and average nucleotide identity between strain 08MAS2615^T and the six Proteus species were 25.5-48.8 % and 82.8-92.9 %, respectively, less than the proposed cutoff level for species delineation, i.e. 70 and 95 %. In addition, the major cellular fatty acid profile of strain 08MAS2615^T was C14 : 0 (12.4 %), C16 : 0 (23.8 %), C17 : 0cyclo (14.4 %), summed feature 2 (C16 : 1iso I/C14 : 0 3-OH) (11.0 %), summed feature 3 (C16 : 1ω7c/16 : 1ω6c) (18.5 %) and summed feature 8 (C18 : 1ω6c) (18.6 %). On the basis of these results, strain 08MAS2615^T represents a novel species of the genus Proteus, for which the name Proteuscolumbae sp. nov. is proposed with strain 08MAS2615^T (=DSM 104686^T=CGMCC 1.15982^T) designated as the species type strain.

Seasonal Microbial Conditions of Locally Made Yoghurt (Shalom) Marketed in Some Regions of Cameroon

The microbial conditions of locally made yoghurt (shalom) marketed in three areas of Cameroon were evaluated during the dry and rainy seasons alongside three commercial brands. A total of ninety-six samples were collected and the microbial conditions were based on total aerobic bacteria (TEB), coliforms, yeasts, and moulds counts as well as the identification of coliforms and yeasts using identification kits. Generally, there was a significant increase (p ≤ 0.05) in total aerobic and coliform counts (especially samples from Bamenda), but a decrease in yeast and mould counts of the same samples during the rainy season when compared to those obtained during the dry season. These counts were mostly greater than the recommended standards. Twenty-one Enterobacteriaceae species belonging to 15 genera were identified from 72 bacterial isolates previously considered as all coliforms. Pantoea sp. (27.77%) was highly represented, found in 41% (dry season) and 50% (rainy season) of samples. In addition, sixteen yeast species belonging to 8 genera were equally identified from 55 yeast isolates and Candida sp. (76.36%) was the most represented. This result suggests that unhygienic practices during production, ignorance, warmer weather, duration of selling, and inadequate refrigeration are the principal causes of higher levels of contamination and unsafe yoghurts.

UPLC-MS/MS analysis of antibiotics in pharmaceutical effluent in Tunisia: ecotoxicological impact and multi-resistant bacteria dissemination

The UPLC MS/MS analysis showed the presence of the two antibiotics in the pharmaceutical industry discharges during 3 months; norfloxacin and spiramycin which were quantified with the mean concentrations of 226.7 and 84.2 ng mL^-1, respectively. Sixteen resistant isolates were obtained from the pharmaceutical effluent and identified by sequencing. These isolates belong to different genera, namely Citrobacter, Acinetobacter, Pseudomonas, Delftia, Shewanella, and Rheinheimera. The antibiotic resistance phenotypes of these isolates were determined (27 tested antibiotics-discs). All the studied isolates were found resistant to amoxicillin and gentamicin, and 83.33% of isolates were resistant to ciprofloxacin. Multiple antibiotic resistances were revealed against β-lactams, quinolones, and aminoglycosides families. Our overall results suggest that the obtained bacterial isolates may constitute potential candidates for bioremediation and can be useful for biotechnological applications. Genotoxic effects were assessed by a battery of biotests; the pharmaceutical wastewater was genotoxic according to the bacterial Vitotox test and micronuclei test. Genotoxicity was also evaluated by the comet test; the tail DNA damages reached 38 and 22% for concentrated sample (10×) and non-concentrated sample (1×), respectively. However, the histological sections of kidney and liver's mice treated by pharmaceutical effluent showed normal histology and no visible structural effects or alterations as cytolysis, edema, or ulcerative necrosis were observed. Residual antibiotics can reach water environment through wastewater and provoke dissemination of the antibiotics resistance and induce genotoxic effects.

First case report of Providencia Rettgeri neonatal sepsis

BACKGROUND

Providencia are gram negative motile rods and is a member of the Enterobacteriaceae family. It consists of five species, namely Providencia alcalifaciens, Providencia rustigianii, Providencia stuartii, Providencia rettgeri and Providencia heimbachae. These are opportunistic pathogens and leads to infections in immunocompromised host. Providencia rettgeri has been associated with the nosocomial infections of the urinary tract and infections of wounds, burns and blood. Providencia rettgeri is very rare cause of neonatal sepsis and we report first case of neonatal late onset sepsis secondary to it.

CASE PRESENTATION

A term male infant presented on day 4 of post-natal life with the complaint of decreased appetite, fast respiration and lethargy. The clinical examination showed features of sepsis and shock with chest radiogram showing pneumonia. The infant was started on invasive ventilation, intravenous fluids, antibiotic and inotropes. The blood culture was suggestive of multi-drug resistant P. rettgeri. The antibiotics were changed according to organism antibiotic susceptibility pattern and infant gradually improved and was discharged successfully.

CONCLUSION

Providencia rettgeri is a very rare organism to cause neonatal sepsis. The management involves early diagnosis, treatment with appropriate antibiotics and finding the source of infection.

Diets Alter the Gut Microbiome of Crocodile Lizards

The crocodile lizard is a critically endangered reptile, and serious diseases have been found in this species in recent years, especially in captive lizards. Whether these diseases are caused by changes in the gut microbiota and the effect of captivity on disease remains to be determined. Here, we examined the relationship between the gut microbiota and diet and disease by comparing the fecal microbiota of wild lizards with those of sick and healthy lizards in captivity. The gut microbiota in wild crocodile lizards was consistently dominated by Proteobacteria (∼56.4%) and Bacteroidetes (∼19.1%). However, the abundance of Firmicutes (∼2.6%) in the intestine of the wild crocodile lizards was distinctly lower than that in other vertebrates. In addition, the wild samples from Guangdong Luokeng Shinisaurus crocodilurus National Nature Reserve also had a high abundance of Deinococcus-Thermus while the wild samples from Guangxi Daguishan Crocodile Lizard National Nature Reserve had a high abundance of Tenericutes. The gut microbial community in loach-fed crocodile lizards was significantly different from the gut microbial community in the earthworm-fed and wild lizards. In addition, significant differences in specific bacteria were detected among groups. Notably, in the gut microbiota, the captive lizards fed earthworms resulted in enrichment of Fusobacterium, and the captive lizards fed loaches had higher abundances of Elizabethkingia, Halomonas, Morganella, and Salmonella, all of which are pathogens or opportunistic pathogens in human or other animals. However, there is no sufficient evidence that the gut microbiota contributes to either disease A or disease B. These results provide a reference for the conservation of endangered crocodile lizards and the first insight into the relationship between disease and the gut microbiota in lizards.

Determination of thermotolerant coliforms present in coconut water produced and bottled in the Northeast of Brazil

Abstract Coconut water is considered to be a natural isotonic drink and its marketing is gradually increasing. The objective of the present study was to evaluate the microbiological quality of the coconut water produced and bottled in the Northeast of Brazil. Products form ten industries from different states in the Northeast of Brazil were analyzed. The most probable number (MPN) method was used to quantify the coliforms. Samples showing positive for coliforms were seeded on ChromAgar Orient plates and the bacteria identified from isolated colonies using the automated system Vitek 2 (BioMérieux), according to the manufacturer's instructions for the preparation of the inoculum, incubation, reading and interpretation. The samples showed thermotolerant coliform counts between 6.0×102 and 2.6×104 MPN/100 mL. The presence of Klebsiella pneumoniae, Morganella morganii and Providencia alcalifaciens was observed. The implementation of preventive methods and monitoring of the water quality by the industries is required.

Genetic diversity of the O antigens of Proteus species and the development of a suspension array for molecular serotyping

Proteus species are well-known opportunistic pathogens frequently associated with skin wound and urinary tract infections in humans and animals. O antigen diversity is important for bacteria to adapt to different hosts and environments, and has been used to identify serotypes of Proteus isolates. At present, 80 Proteus O-serotypes have been reported. Although the O antigen structures of most Proteus serotypes have been identified, the genetic features of these O antigens have not been well characterized. The O antigen gene clusters of Proteus species are located between the cpxA and secB genes. In this study, we identified 55 O antigen gene clusters of different Proteus serotypes. All clusters contain both the wzx and wzy genes and exhibit a high degree of heterogeneity. Potential functions of O antigen-related genes were proposed based on their similarity to genes in available databases. The O antigen gene clusters and structures were compared, and a number of glycosyltransferases were assigned to glycosidic linkages. In addition, an O serotype-specific suspension array was developed for detecting 31 Proteus serotypes frequently isolated from clinical specimens. To our knowledge, this is the first comprehensive report to describe the genetic features of Proteus O antigens and to develop a molecular technique to identify different Proteus serotypes.

Draft Genome Sequences of Extended-Spectrum-Beta-Lactamase-Producing Morganella morganii Strains AA1 and AV1, Isolated from a Freshwater Lake and Eicchorniacrassipes Roots

Two strains of Morganella morganii, AA1 and AV1, were isolated from freshwater and Eicchornia crassipes roots, respectively. Here, we report their draft genome sequences, which are ~3.6 Mb and have 51% G+C content. The predicted coding sequences (3,259 for strain AA1 and 3,345 for strain AV1) encode beta-lactamases, transpeptidases, and penicillin-binding proteins.

Genome Sequence of a Providencia stuartii Strain Isolated from Luciliasericata Salivary Glands

We present here the draft genome sequence of a Providencia stuartii strain, derived from the salivary glands of larval Lucilia sericata, a common blow fly important to forensic, medical, and veterinary science. The genome sequence will help dissect coinfections involving P. stuartii and Proteus mirabilis, as well as blow fly–bacteria interactions.