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production of biogenic amines by lactic acid bacteria and enterobacteria isolated from fresh pork sausages packaged in different atmospheres and kept under refrigeration.the occurrence of in vitro amino acid activity in bacterial strains associated with fresh pork sausages packaged in different atmospheres and kept in refrigeration was studied. the presence of biogenic amines in decarboxylase broth was confirmed by ion-exchange chromatography and by the presence of the corresponding decarboxylase genes by pcr. from the 93 lactic acid bacteria and 100 enterobacteria strains analysed, the decarboxylase medium underestimates the number of biogenic amine-producer st ...201121316866
correlation of fluoroquinolone resistance with expression of qnra gene in kluyvera spp.abstract the objective of the present study was to examine whether the expression of qnra may contribute to a high level of resistance among parent and induced strains of kluyvera spp. two clinical isolates of ciprofloxacin-resistant kluyvera spp. were obtained from livers of diseased chickens, and upon induction with ciprofloxacin, six strains with increased resistance were produced. point mutations in qnra, aac(6')-ib-cr, gyra, gyrb, parc, and pare were investigated by polymerase chain reactio ...201121561380
rectal carriage of extended-spectrum beta-lactamase-producing gram-negative bacilli in community settings in madagascar.extended-spectrum +ƒ-lactamase-producing enterobacteria (esbl-pe) emerged at the end of the 1980s, causing nosocomial outbreaks and/or hyperendemic situations in hospitals and long-term care facilities. in recent years, community-acquired infections due to esbl-pe have spread worldwide, especially across developing countries including madagascar.201121829498
ethanol production from biodiesel-derived crude glycerol by newly isolated kluyvera cryocrescens.the rapidly expanding market for biodiesel has increased the supply and reduced the cost of glycerol, making it an attractive sustainable feed stock for the fuel and chemical industry. glycerol-based biorefinery is the microbial fermentation of crude glycerol to produce fuels and chemicals. a major challenge is to obtain microbes tolerant to inhibitors such as salts and organic solvents present in crude glycerol. microbial screening was attempted to isolate novel strain capable of growing on cru ...201121212944
the ctx-m conundrum: dissemination of plasmids and escherichia coli clones.the ongoing global spread and increased prevalence of ctx-m-type extended-spectrum ß-lactamases in enterobacteriaceae is of great concern. the successful distribution of ctx-m enzymes mainly involves escherichia coli causing systemic as well as urinary tract infections in patients worldwide. ctx-m expression is often associated with coresistance that critically reduces treatments options. the mobilization of bla(ctx-m) genes from their original chromosomal position in various kluyvera species ha ...201121281129
[Severe sepsis, septic shock and secondary multiple organ dysfunction in infection by Kluyvera ascorbata].Kluyvera, a new genus of Enterobacteriaceae, is an emergent pathogen. Kluyvera species have been isolated from sputum, urine, stools, and blood. Kluyvera strains are infrequent but potentially dangerous pathogens in the immunocompetent or immunocompromised host due to their potential to provoke a wide range of infections and their ability to transfer extended spectrum beta lactamase genes. We herein report the case of a teenage male with severe sepsis and septic shock due to K. ascorbata.201121894234
expression of esbl-like activity in infrequently encountered members of the family enterobacteriaceae.a collection of 94 unusual members of the enterobacteriaceae were screened for the presence of extended spectrum β-lactamases (esbls) using the microscan esβl plus dried confirmation panel. presumptively positive strains were then confirmed for the presence of an esbl by double disk diffusion, e-test strips (ab biodisk, solna, sweden) and pcr for shv, tem, and ctx-m2 genes. of the 18 strains initially positive on the esβl panel only three strains (leminorella grimontii, klebsiella ozaenae, and k ...201122139464
kluyvera cryocrescens sepsis in a preterm infant.kluyvera cryocrescens, formerly accepted as a benign saprophytic microorganism, is an opportunistic pathogen and its infection is very rare in humans. this report describes a preterm infant born at 30 weeks of gestational age and successfully treated for k. cryocrescens sepsis in the 3rd week of life. to our knowledge, this is the first case of k. cryocrescens sepsis in a newborn. the potential of k. cryocrescens as a serious pathogen should be recognized especially in patients such as preterm i ...201020495273
performance of a sulfidogenic bioreactor and bacterial community shifts under different alkalinity levels.the performance of a sulfidogenic bioreactor and the response of bacterial populations to influent alkalinity changes were investigated. the bioreactor reached 40% of sulfate removal efficiency (sre) with 0 mg l(-1) of alkalinity, and single-stranded conformation polymorphism profiles showed that some members of bacteroides, dysgonomonas, sporobacter, quinella, and citrobacter became dominant populations. 16s rrna gene library analysis indicated that the actinobacteria group increased from 0% in ...201020688512
occurrence of gram-negative bacteria in hens' eggs depending on their source and storage conditions.the aim of this study was to analyse the qualitative composition of gram-negative microbes, mainly of the family enterobacteriaceae, including pathogenic bacteria such as salmonella, in the albumens and yolks and on the shells of hens' eggs, depending on their source and on the temperature and duration of their storage. a total of 375 table eggs were studied, from a large-scale poultry farm, a small-scale poultry farm and a supermarket. each group was divided into 5 subgroups according to the te ...201021033566
description of gibbsiella quercinecans gen. nov., sp. nov., associated with acute oak decline.gram-negative, facultatively anaerobic bacterial strains were consistently isolated from oak trees displaying symptoms of extensive stem bleeding. in britain, this disorder is called acute oak decline (aod). a similar condition has been noted on species of mediterranean oak in spain. the identity of bacterial isolates from symptomatic trees in both countries was investigated using molecular techniques and phenotypic assays. 16s rrna gene sequencing indicated that the strains were most closely re ...201021115313
isolation of a zoonotic pathogen kluyvera ascorbata from egyptian fruit-bat rousettus aegyptiacus.the egyptian fruit-bat rousettus aegyptiacus which had been raised at the private commercial aquarium in seoul, korea for indoor exhibition was found dead and submitted to college of veterinary medicine, seoul national university for postmortem examination. a pure bacterium of kluyvera ascorbata was isolated from the blood specimen. the isolation of k. ascorbata from fruit bat is very important, because it is the most infectious agent of the genus kluyvera that cause serious diseases to animals ...201019915337
a case of urinary tract infection caused by kluyvera ascorbata in an infant: case report and review of the literature.we experienced a case of urinary tract infection in a 3-month-old child caused by kluyvera ascorbata. the authors report the case and review the literature regarding kluyvera urinary tract infection exclusively in children. kluyvera infection, which had been extremely rare, has increasingly been reported, including urinary tract infection. a prompt identification of kluyvera species in clinical infections is important. recognition of its disease-producing potential and the subsequent initiation ...201020454915
molecular analysis of intestinal microbiota of rainbow trout (oncorhynchus mykiss).the aim of this study was to evaluate different molecular tools based on the 16s rrna gene, internal transcribed spacer, and the rpob gene to examine the bacterial populations present in juvenile rainbow trout intestines. dna was extracted from both pooled intestinal samples and bacterial strains. genes were pcr-amplified and analysed using both temporal temperature gradient gel electrophoresis (ttge) and restriction fragment length polymorphism methods. because of the high cultivability of the ...201019780831
novel chromosome-encoded ctx-m-78 beta-lactamase from a kluyvera georgiana clinical isolate as a putative origin of ctx-m-25 subgroup. 201020421403
culture-dependent and culture-independent characterization of microorganisms associated with aedes aegypti (diptera: culicidae) (l.) and dynamics of bacterial colonization in the midgut.in this work we show that the lumen of aedes aegypti midgut is highly colonized by bacteria that were identified by culture-dependent and culture-independent methods. rdna sequences obtained were compared with those from genbank and the main bacterial genera identified were: serratia, klebsiella, asaia, bacillus, enterococcus, enterobacter,kluyvera and pantoea. all genera were identified in midgut except enterobacter that was observed only in eggs. asaia and pantoea were also identified in eggs ...201020434424
resistance to cephalosporins and carbapenems in gram-negative bacterial pathogens.during the past 15 years, emergence and dissemination of beta-lactam resistance in nosocomial enterobacteriaceae, pseudomonas aeruginosa and acinetobacter baumannii, became a serious problem worldwide. especially the increasing resistance to 3rd and 4th generation cephalosporins and carbapenems is of particular concern. gram-negative bacteria pursue various molecular strategies for development of resistance to these antibiotics: (a) generation of extended-spectrum beta-lactamases (esbl) accordin ...201020537585
one-pot, two-step enzymatic synthesis of amoxicillin by complexing with zn2+.a one-pot, two-step enzymatic synthesis of amoxicillin from penicillin g, using penicillin acylase, is presented. immobilized penicillin acylase from kluyvera citrophila was selected as the biocatalyst for its good ph stability and selectivity. hydrolysis of penicillin g and synthesis of amoxicillin from the 6-aminopenicillanic acid formed and d-p-hydroxyphenylglycine methyl ester were catalyzed in situ by a single enzyme. zinc ions can react with amoxicillin to form complexes, and the yield of ...201020567815
multidrug resistant kluyvera ascorbata septicemia in an adult patient: a case report.abstract:201020587055
blactx-m genes in escherichia coli strains from croatian hospitals are located in new (blactx-m-3a) and widely spread (blactx-m-3a and blactx-m-15) genetic structures.ctx-m-producing escherichia coli isolates from three croatian hospitals were analyzed. all bla(ctx-m-15) genes and one bla(ctx-m-3a) gene resided in widely spread isecp1 transposition modules, but other bla(ctx-m-3a) genes were in a new configuration with two is26 copies, indicating a new event of gene mobilization from a kluyvera ascorbata genome. the study confirmed the role of the e. coli st131 clonal group with incfii-type plasmids in the spread of bla(ctx-m-15) and of incl/m pctx-m3-type pl ...200919188377
species distribution and antimicrobial susceptibility of gram-negative aerobic bacteria in hospitalized cancer patients.nosocomial infections pose significant threats to hospitalized patients, especially the immunocompromised ones, such as cancer patients.200919228413
antibiotic susceptibility profiles of uncommon bacterial species causing severe infections in italy.this study presents the results of the italian "severe infections project" involving bacteria that can be considered rare causes of disease. we isolated 30 uncommon human pathogens from a total of 60 strains (1.2% of all the isolates). the most frequent sources of uncommon human pathogens were primary bloodstream infections (48.3%) and pneumonia (20%). species such as comamonas testosteroni, enterococcus hirae, kluyvera ascorbata, kluyvera cryocrescens, leclercia adecarboxylata and ochrobactrum ...200919567344
enterobacteriaceae and related organisms isolated from nest run cart shelves in commercial shell egg processing facilities.enterobacteriaceae, including salmonella, may be recovered from foods and processing facilities. high levels of enterobacteriaceae in the processing plant environment can be an indication of inadequate sanitation. this experiment was designed to determine if nest run egg carts serve as reservoirs for enterobacteriaceae. eggs that are produced by hens not housed in buildings connected to the processing plant are referred to as nest run. many of these eggs are transported to the plant on carts to ...200919762864
[kluyvera bacteriemia: an epidemic in a moroccan teaching hospital].kluyvera spp is an enterobacterium rarely isolated in medical microbiology, an opportunistic pathogen the clinical significance of which remains unclear. four strains of kluyvera spp were isolated for the first time in the ibn rochd teaching hospital microbiology laboratory. these strains were isolated in hemocultures of four patients hospitalized in the same medical ward, at the same time, and presenting with bacteriemia. an antibiotic susceptibility study allowed identifying the wild phenotype ...200919010629
genetic transformation of midgut bacteria from the red imported fire ant (solenopsis invicta).in our previous study we isolated 10 bacterial species from fourth-instar larval midguts of the red imported fire ant, solenopsis invicta. here we report the genetic transformation and reintroduction of three species (kluyvera cryocrescens, serratia marcescens, and isolate 38) into the fire ant host. all three species were transformed with the plasmid vector, pzeodsred. high expression levels of dsred were observed and the plasmid is maintained in these bacteria at 37 degrees c in the absence of ...200919159973
the spread of ctx-m-type extended-spectrum beta-lactamases.ctx-m-type enzymes are a group of class a extended-spectrum beta-lactamases (esbls) that are rapidly spreading among enterobacteriaceae worldwide. more that 50 allotypes are known, clustered into six sub-lineages. the ctx-m-encoding genes have been captured from the chromosome of kluyvera spp. on conjugative plasmids that mediate their dissemination among pathogenic enterobacteria. ctx-m-type esbls exhibit powerful activity against cefotaxime and ceftriaxone but generally not against ceftazidime ...200818154526
high rate of mobilization for blactx-ms.we constructed a phylogenetic analysis of class a beta-lactamases and found that the blactx-ms have been mobilized to plasmids approximately 10 times more frequently than other class a beta-lactamases. we also found that the blactx-ms are descended from a common ancestor that was incorporated in ancient times into the chromosome of the ancestor of kluyvera species through horizontal transfer. considerable sequence divergence has occurred among the descendents of that ancestral gene sequence sinc ...200818325257
detection of protozoan and bacterial pathogens of public health importance in faeces of corvus spp. (large-billed crow).parasites and bacteria are reported in the faeces of birds in the current study. fresh faecal samples of the large-billed crow (corvus spp.) were collected from the study site at bangsar, an urban setting in kuala lumpur, malaysia. these samples were transported to laboratory and analysed for parasites and bacteria. pre-prepared xld agar plates were used for culturing the bacteria in the laboratory. using the api 20etm test strips, 9 different species of bacteria were identified belonging to the ...200818948884
urinary tract infection caused by kluyvera ascorbata in a child: case report and review of the kluyvera infections in children.kluyvera species are described infrequently in association with clinically significant infections, and infections caused by these gram negative rods are rare in children. the spectrum of disease due to kluyvera infection in children includes urinary tract infections, enteritis, soft tissue infections, sepsis, central venous catheter infections and peritonitis. the authors report a case of kluyvera ascorbata urinary tract infection in a 3-month-old female baby, and they review the literature on k ...200818971906
genetic and structural insights into the dissemination potential of the extremely broad-spectrum class a beta-lactamase kpc-2 identified in an escherichia coli strain and an enterobacter cloacae strain isolated from the same patient in france.two clinical strains of escherichia coli (2138) and enterobacter cloacae (7506) isolated from the same patient in france and showing resistance to extended-spectrum cephalosporins and low susceptibility to imipenem were investigated. both strains harbored the plasmid-contained bla(tem-1) and bla(kpc-2) genes. bla(kluc-2), encoding a mutant of the chromosomal beta-lactamase of kluyvera cryocrescens, was also identified at a plasmid location in e. cloacae 7506, suggesting the isecp1-assisted escap ...200818625772
beta-lactam induction of isecp1b-mediated mobilization of the naturally occurring bla(ctx-m) beta-lactamase gene of kluyvera ascorbata.isecp1b is an insertion element associated with the emerging expanded-spectrum beta-lactamase bla(ctx-m) genes in enterobacteriaceae. because isecp1b-bla(ctx-m)positive strains may be identified from humans and animals, the ability of this insertion sequence to mobilize the bla(ctx-m-2) gene was tested from its progenitor kluyvera ascorbata to study the effects of amoxicillin/clavulanic and cefquinome as enhancers of transposition. these beta-lactam molecules are administered parenterally to tre ...200819054083
isolation and endotoxin activities of lipopolysaccharides from cyanobacterial cultures and complex water blooms and comparison with the effects of heterotrophic bacteria and green alga.massive cyanobacterial water blooms are serious environmental and health problems worldwide. while some cyanobacterial toxins such as peptide microcystins have been investigated extensively, other toxic components of cyanobacteria (e.g. lipopolysaccharides, lps) are poorly understood. the present study characterized endotoxin activities of lps isolated from (i) laboratory cyanobacterial cultures, (ii) cyanobacterial water bloom samples dominated by microcystis sp., planktothrix sp., aphanizomeno ...200817461433
sugarcane bagasse mild alkaline/oxidative pretreatment for ethanol production by alkaline recycle process.in order to decrease the alkali and water consumptions in the sugarcane bagasse alkaline/oxidative pretreatment for ethanol production, an alkaline recycle process was carried out. two recycles of naoh/h2o2 pretreatment did not decrease the pretreatment and enzymatic hydrolysis efficiencies and the consumptions of naoh and water would be saved by 26% and 40%, respectively. a simultaneous saccharification and fermentation (ssf) culture with pretreated bagasse as substrate was developed giving 25 ...200818327542
enterobacteriaceae and related organisms isolated from shell eggs collected during commercial processing.in the united states, commercial shell eggs are washed and graded before retail. since passage of the egg products inspection act in 1971, processing guidelines have been set to ensure that external and internal characteristics are maintained. however, less is known about how commercial processing affects the safety of shell eggs. to identify enteric bacteria entering plants and persisting throughout processing, eggs were collected from 3 us commercial shell egg-processing plants on 3 separate v ...200818493013
hickman catheter-related bacteremia with kluyvera cryocrescens: a case report.this report describes a 2-year-old child with neuroectodermal tumor presenting with febrile neutropenia. blood cultures drawn from the peripheral vein and hickman catheter revealed kluyvera cryocrescens growth. the hickman catheter was removed and the patient was successfully treated with cefepime and amikacin. isolation of kluyvera spp. from clinical specimens is rare. this saprophyte microorganism may cause serious central venous catheter infections, especially in immunosuppressed patients. cl ...200818503178
a plasmid-borne shewanella algae gene, qnra3, and its possible transfer in vivo between kluyvera ascorbata and klebsiella pneumoniae.the plasmid-borne quinolone resistance gene qnra1 is prevalent in multidrug-resistant enterobacteriaceae. a chromosomally encoded homologue in shewanella algae, qnra3, has been described. we isolated two qnra3-positive strains, one of klebsiella pneumoniae (he96) and one of kluyvera ascorbata (kas96), from the feces of an immunocompromised outpatient. the qnra3 allele was identical to that of s. algae except for 5 nucleotides and differed from qnra1 by 29 nucleotides affecting three amino acids. ...200818515416
prevalence and clonality of extended-spectrum beta-lactamases in asia.asia is almost certainly a part of the world in which extended-spectrum beta-lactamases (esbls) have emerged de novo, with some early antimicrobial resistance studies showing high levels of the esbl phenotype, particularly among klebsiella, and most notably in china, korea, japan and india. there is a lack of genotyping studies but work from the late 1990s suggests that shv-5 and shv-12 were most common then, with only very rare reports of tem-related esbl genes. as in other parts of the world, ...200818154540
type 3 fimbriae, encoded by the conjugative plasmid pola52, enhance biofilm formation and transfer frequencies in enterobacteriaceae strains.the conjugative plasmid pola52, which confers resistance to olaquindox and other antimicrobial agents through a multidrug efflux pump, was investigated for its ability to promote biofilm formation in escherichia coli. screening of a transposon-mutagenized pola52 clone library revealed several biofilm-deficient mutants, which all mapped within a putative operon with high homology to the mrkabcdf operon of klebsiella pneumoniae, where these genes are responsible for type 3 fimbriae expression, att ...200818174137
kluyvera infections in the pediatric population.in pediatric patients, kluyvera spp. has emerged as a cause of disease ranging from soft tissue infections to sepsis with multiorgan failure. successful treatment options include third-generation cephalosporins, tetracycline, aminoglycosides, and fluoroquinolones, but resistance to first- and second-generation cephalosporins persists. clinicians should be aware of the spectrum of disease and increasing clinical importance associated with this emerging pathogen.200818645547
the genome and proteome of the kluyvera bacteriophage kvp1--another member of the t7-like autographivirinae.kluyvera, a genus within the family enterobacteriaceae, is an infrequent cause of human infections. bacteriophage kvp1, the only bacteriophage isolated for one of its species, kluyvera cryocrescens, is a member of the viral family podoviridae.200818937848
substrate specificity of the oqxab multidrug resistance pump in escherichia coli and selected enteric bacteria.a plasmid-encoded multidrug efflux pump, oqxab, identified in escherichia coli of porcine origin, was tested for substrate specificity against selected antibiotics, detergents and disinfectants. the ability of horizontal transfer to food-borne pathogens of the enterobacteriaceae family was also investigated.200717526501
[reaction of microorganisms to the digestive fluid of the earthworms].the reaction of soil bacteria and fungi to the digestive fluid of the earthworm aporrectodea caliginosa was studied. the fluid was obtained by centrifugation of the native enzymes of the digestive tract. the inhibition of growth of certain bacteria, spores, and fungal hyphae under the effect of extracts from the anterior and middle sections of the digestive tract of a. caliginosa was discovered for the first time. in bacteria, microcolony formation was inhibited as early as 20-30 s after the app ...200717410875
kluyvera meningitis in a newborn.kluyvera is described infrequently in association with clinically significant infections in humans. it can produce a wide range of clinically significant manifestations. we describe a newborn with ventriculoperitoneal shunt, who was successfully treated for kluyvera meningitis. we believe that this is the first case of kluyvera central nervous system infection reported in a child.200717984822
multiple antimicrobial resistance in enterobacteriaceae isolates from pristine freshwater.a freshwater enterobacterial population (n = 111) was studied for antimicrobial and mercury resistance patterns, and for its possible association with biotic and abiotic factors in that environment. conventional biochemical tests identified klebsiella sp, morganella sp, serratia sp, escherichia sp, enterobacter sp, edwarsiella sp, proteus sp, citrobacter sp, providencia sp, and kluyvera sp. there was no correlation between antimicrobial resistance patterns of isolates and bacterial genera, but r ...200717985304
impact of conjugal transfer on the stability of incp-1 plasmid pkjk5 in bacterial populations.the intrinsic stability of incp-1 plasmid pkjk5 was assessed in both an escherichia coli and a kluyvera sp. population maintained in bacterial mats and in liquid nutrient broth without selective pressure. a fluorescence tagging/flow cytometry approach was used to detect and quantify plasmid loss from populations harboring either conjugation-proficient or -deficient pkjk5 derivatives. the results show that the plasmid's ability to conjugate plays an important role in its stable maintenance in pop ...200717132149
phylogenetic analysis of enteric species of the family enterobacteriaceae using the oric-locus.phylogenetic analysis of 38 enteric species belonging to the enterobacteraceae family was carried out using the non-coding locus oric, the chromosomal replication origin. the oric loci were amplified with conserved oligonucleotides and the pcr fragments were sequenced directly. the results establish a phylogenetic tree for the classification of different species of the genera escherichia, shigella, salmonella, enterobacter, citrobacter, klebsiella, raoultella, kluyvera, cedecea and buttiauxella. ...200716904857
comparison of disk diffusion, vitek 2, and broth microdilution antimicrobial susceptibility test results for unusual species of enterobacteriaceae.we compared the antimicrobial susceptibility testing results generated by disk diffusion and the vitek 2 automated system with the results of the clinical and laboratory standards institute (clsi) broth microdilution (bmd) reference method for 61 isolates of unusual species of enterobacteriaceae. the isolates represented 15 genera and 26 different species, including buttiauxella, cedecea, kluyvera, leminorella, and yokenella. antimicrobial agents included aminoglycosides, carbapenems, cephalospo ...200717135429
complete nucleotide sequence of the pctx-m3 plasmid and its involvement in spread of the extended-spectrum beta-lactamase gene blactx-m-3.here we report the nucleotide sequence of pctx-m3, a highly conjugative plasmid that is responsible for the extensive spread of the gene coding for the ctx-m-3 extended-spectrum beta-lactamase in clinical populations of the family enterobacteriaceae in poland. the plasmid belongs to the incl/m incompatibility group, is 89,468 bp in size, and carries 103 putative genes. besides bla(ctx-m-3), it also bears the bla(tem-1), aacc2, and arma genes, as well as integronic aada2, dfra12, and sul1, which ...200717698626
effects of induction starting time and ca2+ on expression of active penicillin g acylase in escherichia coli.formation of inclusion bodies is an important obstacle to the production of active recombinant protein in escherichia coli. thus, soluble expression of penicillin g acylase from kluyvera citrophila was investigated in bl21(de3). in this study, the yield of active enzyme was significantly enhanced by the composition of the medium and induction opportunity. when 0.5 mmol/l iptg was added to complex medium at 15 h after incubation, the volumetric and specific activities of penicillin g acylase both ...200717824667
characterisation of klua-9, a beta-lactamase from extended-spectrum cephalosporin-susceptible kluyvera ascorbata, and genetic organisation of bla(klua-9).this study characterised the genetic environment of the chromosomally encoded bla(klua-9) gene from a clinical kluyvera ascorbata isolate and performed a kinetic characterisation of klua-9. purified klua-9 showed the highest catalytic efficacies towards benzylpenicillin, ampicillin, piperacillin, first-generation cephalosporins, cefuroxime and cefoperazone; like other 'cefotaximases', it showed a much higher rate of hydrolysis of cefotaxime than ceftazidime, whilst dicloxacillin, cefoxitin and i ...200717196371
occurrence of strains producing specific antibacterial inhibitory agents in five genera of enterobacteriaceae.striking differences in the production of specific inhibitory agents affecting other strains of the same (or of related) species were found between genera of the family enterobacteriaceae. we tested 50-163 strains each of the potentially pathogenic genera: escherichia, citrobacter, enterobacter, kluyvera, and leclercia for their ability to produce bacteriophages, high-molecular-weight (hmw) and low-molecular-weight (lmw) bacteriocins and siderophores against the same sets of strains, using the c ...200717211543
kluyvera co-infection in two solid organ transplant recipients: an emerging pathogen or a colonizer bystander?kluyvera species are opportunistic, gram-negative bacilli in the family enterobacteriaceae. ordinarily occurring as a commensal, kluyvera have been reported to cause serious infections in immunosuppressed and immunocompetent hosts, causing diarrhea, urinary infections, peritonitis, and cholecystitis. we report kluyvera infections in 2 solid organ transplant recipients. an 18-year-old female with alpha-1 antitrypsin deficiency underwent living donor liver transplantation and presented 6 months la ...200717313481
isolation and characterization of cultivable fermentative bacteria from the intestine of two edible snails, helixpomatia and cornu aspersum (gastropoda: pulmonata).the intestinal microbiota of the edible snails cornu aspersum fsyn: h. aspersa), and helix pomatia were investigated by culture-based methods, 16s rrna sequence analyses and phenotypic characterisations. the study was carried out on aestivating snails and two populations of h. pomatia were considered. the cultivable bacteria dominated in the distal part of the intestine, with up to 5.10(9) cfu g -1, but the swedish h. pomatia appeared significantly less colonised, suggesting a higher sensitivity ...200717657348
isolation and antimicrobial sensitivities of kluyvera spp. from humans in england, wales and northern ireland, 2005-2006. 200717669632
[pyrazinamidase activity of bacteria from enterobacteriaceae family as characteristic for taxonomy].pyrazinamidase activity in 330 strains of bacteria from enterobacteriaceae family (14 genus, 27 species) has been assessed. pyrazinamidase activity detected in species from following genuses: citrobacter, escherichia, klebsiella, kluyvera, morganella, providencia, raourtella, salmonella, shigella, and also in proteus mirabilis, and nonpathogenic serovars of yersinia enterocolitica, y. frederiksenii. pirasinamidase was absent in serratia (s. marcescens, s. liguefaciens), hafnia alvei, p. vulgaris ...200617297889
the ctx-m beta-lactamase pandemic.in the past decade ctx-m enzymes have become the most prevalent extended-spectrum beta-lactamases, both in nosocomial and in community settings. the insertion sequences (iss) isecp1 and iscr1 (formerly common region 1 [cr1] or orf513) appear to enable the mobilization of chromosomal beta-lactamase kluyvera species genes, which display high homology with blactx-ms. these iss are preferentially linked to specific genes: isecp1 to most blactx-ms, and iscr1 to blactx-m-2 or blactx-m-9. the blactx-m ...200616942899
in vitro analysis of isecp1b-mediated mobilization of naturally occurring beta-lactamase gene blactx-m of kluyvera ascorbata.isecp1b has been reported to be associated with and to mobilize the emerging expanded-spectrum beta-lactamase blactx-m genes in enterobacteriaceae. thus, the ability of this insertion sequence to mobilize the blactx-m-2 gene was tested from its progenitor, kluyvera ascorbata. insertions of isecp1b upstream of the blactx-m-2 gene in k. ascorbata reference strain cip7953 were first selected with cefotaxime (0.5 and 2 microg/ml). in those cases, isecp1b brought promoter sequences enhancing blactx-m ...200616569841
effect of organic cosolvent on kinetic resolution of tert-leucine by penicillin g acylase from kluyvera citrophila.penicillin g acylase (pga) from kluyvera citrophila immobilized on amberzyml was used for enantioselective hydrolysis of n-phenylacetylated-dl-tert-leucine (n-phac-dl-tle) to produce l-tert-leucine (l-tle). the effects of various organic cosolvents on hydrolysis of n-phac-dl-tle have been investigated in aqueous-cosolvent medium. it was founded that the rate of pga-catalyzed reaction was significantly affected by the presence of 2% (v/v) organic cosolvent concentration. the initial rate fell wit ...200616245080
the effect of decreasing alkalinity on microbial community dynamics in a sulfate-reducing bioreactor as analyzed by pcr-sscp.pcr-single-strand conformation polymorphism (sscp) and southern blotting techniques were adopted to investigate microbial community dynamics in a sulfate-reducing bioreactor caused by decreasing influent alkalinity. experimental results indicated that the sulfate-removal rate approached 87% in 25 d under the conditions of influent alkalinity of 4000 mg/l (as caco3) and sulfate-loading rate of 4.8 g/(l*d), which indicated that the bioreactor started up successfully. the analysis of microbial comm ...200616989283
preparation of optically pure tert-leucine by penicillin g acylase-catalyzed resolution.penicillin g acylase, from kluyvera citrophila, was used in kinetic resolution of dl-tert-leucine. n-phenylacetylated-dl-tert-leucine, chemically synthesized from dl-tert-leucine, was enantioselctively hydrolyzed by penicillin g acylase to obtain l-tert-leucine, d-tert-leucine was prepared by acid-catalyzed hydrolysis of the remaining substrate. the total yields of d-tert-leucine and l-tert-leucine are 80.6% and 83.1%, respectively. the enantiomeric excess of the two products, d-tert-leucine and ...200616707334
characterization of the enterobacteriaceae isolated from an artisanal italian ewe's cheese (pecorino abruzzese).to evaluate some physiological characteristics of the enterobacteriaceae isolated from pecorino cheese.200616882142
expression and purification of penicillin g acylase enzymes from four different micro-organisms, and a comparative evaluation of their synthesis/hydrolysis ratios for cephalexin.several genes for the enzyme penicillin g acylase, as isolated from four different micro-organisms (alcaligenes facaelis, escherichia coli, kluyvera cryocrescens or providencia rettgeri) were modified at their carboxy-termini to include his-tag fusions, then were expressed from the plasmid pet-24a(+) in e. coli jm109(de3) cells. all fusion proteins were next purified to homogeneity in a single step by agar-based co-ida chromatography, and were then evaluated as catalysts for the synthesis of cep ...200616139515
clinically significant kluyvera infections: a report of seven cases.to determine the clinical significance of kluyvera isolates at our institution, we retrospectively analyzed clinical microbiology data from january 1999 to september 2003. we identified 11 isolates classified as kluyvera ascorbata, 7 of which were considered clinically significant pathogens: 3 cases represented urinary tract infections; 2, bacteremia; 1, a soft tissue infection of the finger; and 1, acute appendicitis with a subsequent intra-abdominal abscess. the age distribution of patients wa ...200515716228
description of in116, the first blactx-m-2-containing complex class 1 integron found in morganella morganii isolates from buenos aires, argentina.we analysed the architecture and probable origin of a class 1 integron from cefotaxime-resistant morganella morganii isolates.200515743901
natural antimicrobial susceptibility patterns of kluyvera ascorbata and kluyvera cryocrescens strains and review of the clinical efficacy of antimicrobial agents used for the treatment of kluyvera infections.the natural susceptibility of 58 k. ascorbata and 24 k. cryocrescens strains to 71 antimicrobial agents was investigated. mic values were determined with a microdilution procedure in cation-adjusted mueller hinton broth (for all strains) and isosensitest broth (for some strains). both species were naturally sensitive or of intermediate susceptibility to tetracyclines, aminoglycosides, quinolones, antifolates, chloramphenicol, nitrofurantoin, fosfomycin, aminopenicillins plus beta-lactamase inhib ...200515920899
kluyvera urinary tract infection: case report and review of the literature.we report the occurrence of kluyvera ascorbata urinary tact infection, presenting as acute pyelonephritis, in a 19-month-old girl without underlying uropathy. quick response to antibiotic therapy was obtained, and there was no residual renal parenchymal damage. we review the literature of infections with this very uncommon organism with particular emphasis on pediatric urinary tract infections.200515933577
ctx-m: changing the face of esbls in the uk.the uk has experienced a sudden rise in extended-spectrum beta-lactamase (esbl) rates, largely due to the appearance and spread of escherichia coli producing ctx-m-15 type beta-lactamase. the british society for antimicrobial chemotherapy organized two update meetings during 2004 to report and discuss the recognition, clinical diagnosis, treatment and control of bacteria producing these beta-lactamases. this paper reports the data and reviews made by contributors to the conferences. the historic ...200516006451
first case of septicemia due to a strain belonging to enteric group 58 (enterobacteriaceae) and its designation as averyella dalhousiensis gen. nov., sp. nov., based on analysis of strains from 20 additional cases.when enteric group 58 was first described as a distinct new group of enterobacteriaceae in 1985, there were only five known human isolates: four from wounds and one from feces. in 1996, we investigated the first blood isolate of enteric group 58, a case of sepsis in a 33-year-old woman receiving total parenteral nutrition. fifteen additional clinical isolates have since been identified at cdc, including several recognized from a collection of "unidentified" strains dating back to 1973. all strai ...200516207983
correlation between diverse cyclic lipopeptides production and regulation of growth and substrate utilization by bacillus subtilis strains in a particular habitat.the two bacillus subtilis strains (dm-03 and dm-04) were isolated from two extremely different habitats; one from the traditional fermented food and another one from a petroleum contaminated soil sample. these strains produced quantitatively and qualitatively different cyclic lipopeptides isoforms under laboratory culture conditions. maldi-tof mass spectral analysis revealed that lipopeptide profile varied according to the producing b. subtilis strains; iturins and surfactins isoforms were pre-d ...200516332345
soft tissue infection caused by kluyvera species. 200515665722
identification of a progenitor of the ctx-m-9 group of extended-spectrum beta-lactamases from kluyvera georgiana isolated in guyana.chromosomal beta-lactamase genes (bla(kluy)) from six kluyvera georgiana strains isolated in guyana were cloned and expressed in escherichia coli. kluy-1 exhibited 100% amino acid identity with the extended-spectrum beta-lactamase ctx-m-14. we also show that a 2.7-kb kluyvera chromosomal region exhibits 99% nucleotide identity to a portion of in60 that includes bla(ctx-m-9).200515855541
urinary tract infection caused by kluyvera ascorbata in an immunocompromised patient: case report and review.we describe an immunocompromised patient, aged 78 y, with urinary tract infection caused by kluyvera ascorbata. complete recovery was achieved on antibiotic therapy with ceftriaxone. review of the literature clearly indicates that k. ascorbata is a potentially dangerous pathogen either in the immunocompetent or in the immunocompromised host. k. ascorbata, and in general kluyvera species, deserve prompt identification in order to determine antimicrobial susceptibility pattern and a correct and ag ...200516051578
phylogenetic relationships of the genus kluyvera: transfer of enterobacter intermedius izard et al. 1980 to the genus kluyvera as kluyvera intermedia comb. nov. and reclassification of kluyvera cochleae as a later synonym of k. intermedia.in order to assess the relationship between the genus kluyvera and other members of the family enterobacteriaceae, the 16s rrna genes of type strains of the recognized kluyvera species, kluyvera georgiana, kluyvera cochleae, kluyvera ascorbata and kluyvera cryocrescens, were sequenced. a comparative phylogenetic analysis based on these 16s rrna gene sequences and those available for strains belonging to several genera of the family enterobacteriaceae showed that members of the genus kluyvera for ...200515653915
[respiratory infection by kluyvera sp. cause or consequence?]. 200515777126
monitoring of microbial community structure and succession in the biohydrogen production reactor by denaturing gradient gel electrophoresis (dgge).to study the structure of microbial communities in the biological hydrogen production reactor and determine the ecological function of hydrogen producing bacteria, anaerobic sludge was obtained from the continuous stirred tank reactor (cstr) in different periods of time, and the diversity and dynamics of microbial communities were investigated by denaturing gradient gel electrophoresis (dgge). the results of dgge demonstrated that an obvious shift of microbial population happened from the beginn ...200515986888
supercooling ability in two populations of the land snail helix pomatia (gastropoda: helicidae) and ice-nucleating activity of gut bacteria.the land snail helix pomatia (gastropoda: helicidae) is widely distributed in northern and central europe where it may experience subzero temperatures during winter months. its supercooling ability was studied in two populations of h. pomatia. one population originated from southern sweden (gotaland) and the other from central france (auvergne). in the experimental design, they were acclimated, over 2 weeks, to artificial winter conditions (hibernation, t=5 degrees c). the swedish snails showed ...200415710369
identification of enterobacteriaceae from washed and unwashed commercial shell eggs.to evaluate the effect of processing on the safety and quality of retail shell eggs, a storage study was conducted with unwashed and commercially washed eggs. this work demonstrated that commercial processing decreased microbial contamination of eggshells. to know which species persisted during storage on washed or unwashed eggs, enterobacteriaceae isolates were selected and identified biochemically. for each of three replications, shell eggs were purchased from a commercial processing plant, tr ...200415553650
chromosome-encoded ctx-m-3 from kluyvera ascorbata: a possible origin of plasmid-borne ctx-m-1-derived cefotaximases.a gene identical to plasmid-borne bla(ctx-m-3) is present in the chromosome of one kluyvera ascorbata strain. it is associated with a structure including an inverted repeat right and an open reading frame 477-like gene probably involved in the mobilization of bla(ctx-m-3). two other k. ascorbata strains rendered the previously described bla(klua-9) gene.200415561876
evidence for the involvement of arginyl residue at the active site of penicillin g acylase from kluyvera citrophila.penicillin g acylase (pga) is used for the commercial production of semi-synthetic penicillins. it hydrolyses the amide bond in penicillin producing 6-aminopenicillanic acid and phenylacetate. 6-aminopenicillanic acid, having the beta-lactam nucleus, is the parent compound for all semi-synthetic penicillins. penicillin g acylase from kluyvera citrophila was purified and chemically modified to identify the role of arginine in catalysis. modification with 20 mm phenylglyoxal and 50 mm 2,3-butanedi ...200415604805
cloning, overexpression, and characterization of a novel thermostable penicillin g acylase from achromobacter xylosoxidans: probing the molecular basis for its high thermostability.the gene encoding a novel penicillin g acylase (pga), designated pgaw, was cloned from achromobacter xylosoxidans and overexpressed in escherichia coli. the pgaw gene contains an open reading frame of 2586 nucleotides. the deduced protein sequence encoded by pgaw has about 50% amino acid identity to several well-characterized pgas, including those of providencia rettgeri, kluyvera cryocrescens, and escherichia coli. biochemical studies showed that the optimal temperature for this novel pga (pga6 ...200415128530
expression, purification, and characterization of his-tagged penicillin g acylase from kluyvera citrophila in escherichia coli.the dna fragment encoding kluyvera citrophila penicillin g acylase (kcpga) was amplified and cloned into the vector pet28b to obtain a c-terminus his-tagged fusion expression plasmid. the fusion protein kcpga was successfully overexpressed in escherichia coli bl21(de3). the optimal induction concentration of isopropylthio-beta-d-galactoside (iptg) was found to be 5 microm. the fusion protein was purified in a single step by ni-ida affinity chromatograph to a specific activity of 35.3u/mg protein ...200415477078
cefotaximases (ctx-m-ases), an expanding family of extended-spectrum beta-lactamases.among the extended-spectrum beta-lactamases, the cefotaximases (ctx-m-ases) constitute a rapidly growing cluster of enzymes that have disseminated geographically. the ctx-m-ases, which hydrolyze cefotaxime efficiently, are mostly encoded by transferable plasmids, and the enzymes have been found predominantly in enterobacteriaceae, most prevalently in escherichia coli, salmonella typhimurium, klebsiella pneumoniae, and proteus mirabilis. isolates of vibrio cholerae, acinetobacter baumannii, and a ...200415105882
fatal emphysematous gastritis in a 2-year-old child with chronic renal failure. 200415383939
occurrence and phenotypic characteristics of extended-spectrum beta-lactamases among members of the family enterobacteriaceae at the tel-aviv medical center (israel) and evaluation of diagnostic tests.we assessed the prevalence and phenotypic characteristics of extended-spectrum beta-lactamase (esbl) producers among cefuroxime-resistant (cxm-r) (mic > or = 32 micro g/ml) members of the family enterobacteriaceae in our institution. the 438 cxm-r clinical isolates obtained from nonurine sources among inpatients were screened. esbl production was confirmed by disk diffusion assay using cefpodoxime (cpd), cefotaxime (ctx), and ceftazidime (ctz) with and without clavulanate (clav). a difference of ...200312517841
improving the specific synthetic activity of a penicillin g acylase using dna family shuffling.penicillin g acylas (pga) of providencia rettgeri (atcc 25599) was evolved using a modified dna family shuffling method. the identity of pga genes from escherichia coli, kluyvera citrophila and providencia rettgeri ranges from 62.5% to 96.9%. the pga genes from above three species were recombined and shuffled to create interspecies pga gene fusion libraries. by substituting assembled chimaeras for corresponding region of petppga, different recombinants were constructed and expressed in e. coli j ...200312796820
central venous catheter infection in a child: case report and review of kluyvera infection in children.kluyvera is an opportunistic pathogen that can occur in immunosuppressed as well as immunocompetent hosts. we report a case of kluyvera species infection involving a central venous catheter, and we review the literature on kluyvera infections in children. our case demonstrates that removal of the central venous catheter was necessary to eradicate the infection and hasten the resolution of refractory neutropenia. the spectrum of disease due to kluyvera infection in children includes central venou ...200312630654
the incidence of oral gram-negative bacteria in patients with parkinson's disease.background: parkinson's disease is a common neurodegenerative disorder that affects an increasing number of older people every year. dysphagia is not only a common feature, but one that results in poor nutrition and an increased risk of bronchopneumonia. previous work has suggested that the oral flora is altered in patients with oral pathology. methods: fifty patients were assessed to quantify the incidence of oral gram-negative bacteria. results: sixteen of the patients with parkinson's disease ...200314962700
polymorphism in the yclc-rpos region of enterobacteria.the nucleotide sequence downstream from the rpos gene in enterobacter cloacae and kluyvera cryocrescens contains the slya-pad1-yclc genes. the dna sequence of enterobacter cloacae cetc960 shows a 2.6-kb insertion of unknown origin between rpos and slya. this 2.6-kb sequence has also been detected in species of salmonella and in pseudomonas aeruginosa, but not in the same location. this insertion has been detected in all the enterobacter cloacae clinical strains studied although the size of the r ...200312732965
moraxella and kluyvera peritonitis in a capd patient with human immunodeficiency virus. 200314703211
beta-lactamases of kluyvera ascorbata, probable progenitors of some plasmid-encoded ctx-m types.kluyvera ascorbata produces a beta-lactamase that results in an atypical susceptibility pattern, including low-level resistance to penicillins, cephalothin, and cefuroxime, but this resistance is reversed by clavulanate. ten nucleotide sequences of the corresponding gene, bla(klua), were obtained and were found to have minor variations (96 to 100%). otherwise, bla(klua) was found to be similar (95 to 100%) to some plasmid-encoded ctx-m-type beta-lactamases. finally, mobilization of bla(klua) on ...200212183268
study of the bacterial load in a gelatine production process focussed on bacillus and related endosporeforming genera.gelatine is an animal protein with many industrial applications. previous studies pointed out that endosporeforming bacteria, belonging to the genus bacillus or related genera, might contaminate and survive the production process of gelatine, leading to products of low quality and safety. the aim of this study is to determine the bacterial diversity of contaminants isolated from a gelatine production chain with emphasis on aerobic endosporeforming bacteria. contaminants were isolated from sample ...200212583722
identification of a chromosome-borne expanded-spectrum class a beta-lactamase from erwinia persicina.from whole-cell dna of an enterobacterial erwinia persicina reference strain that displayed a penicillinase-related antibiotic-resistant phenotype, a beta-lactamase gene was cloned and expressed in escherichia coli. it encoded a clavulanic-acid-inhibited ambler class a beta-lactamase, erp-1, with a pi value of 8.1 and a relative molecular mass of ca. 28 kda. erp-1 shared 45 to 50% amino acid identity with the most closely related enzymes, the chromosomally encoded enzymes from citrobacter koseri ...200212384342
chromosome-encoded ambler class a beta-lactamase of kluyvera georgiana, a probable progenitor of a subgroup of ctx-m extended-spectrum beta-lactamases.a chromosome-encoded beta-lactamase gene, cloned and expressed in escherichia coli from kluyvera georgiana reference strain cuetm 4246-74 (dsm 9408), encoded the extended-spectrum beta-lactamase klug-1, which shared 99% amino acid identity with the plasmid-mediated beta-lactamase ctx-m-8. this work provides further evidence that kluyvera spp. may be the progenitor(s) of ctx-m-type beta-lactamases.200212435721
identification of tem-10 beta-lactamase in a kluyvera sp. and other enterobacteriaceae at a portuguese hospital. 200212435722
novel class 1 integron (ins21) carrying blactx-m-2 in salmonella enterica serovar infantis.the genetic organization of the region coding for ctx-m-2 in salmonella enterica serovar infantis was determined by pcr mapping. this gene seems to have been mobilized from the kluyvera ascorbata chromosome to a complex suli-type integron, similar to in6 and in7.200212069984
blactx-m-2 is located in an unusual class 1 integron (in35) which includes orf513.examination of the bla(ctx-m-2) gene in plasmid pmar-12 by sequencing and pcr analysis revealed that the bla gene and the surrounding dna, which is closely related (99% homology) to the kluyvera ascorbata chromosomal dna that contains the bla(klua-1) gene, are located in a complex sul1-type integron, termed in35, that includes orf513. it is possible that bla(ctx-m-2) was acquired by plasmid pmar-12 through an uncharacterized recombinational event in which orf513 could be involved.200212069995
nosocomial outbreak of kluyvera cryocrescens bacteremia. 200211893149
diversity of ctx-m beta-lactamases and their promoter regions from enterobacteriaceae isolated in three parisian hospitals.nine clinical isolates of enterobacteriaceae (six escherichia coli and three proteus mirabilis) isolated in three parisian hospitals between 1989 and 2000 showed a particular extended-spectrum cephalosporin-resistance profile characterized by resistance to cefotaxime and aztreonam but not to ceftazidime. ctx-m-1, ctx-m-2, ctx-m-9, ctx-m-14 and two novel plasmid-mediated ctx-m beta-lactamases (ctx-m-20, and ctx-m-21) were identified by polymerase chain reaction and isoelectric focusing (pi>8) and ...200212007800
[acute cholecystitis due to kluyvera ascorbata]. 200212237007
nucleotide sequence and characterization of a novel cefotaxime-hydrolyzing beta-lactamase (ctx-m-10) isolated in spain.a cefotaxime-resistant, ceftazidime-susceptible escherichia coli isolate was obtained from a patient with sepsis in 1997, from which a beta-lactamase with a pi of 8.1 was cloned. cephaloridine and cefotaxime relative hydrolysis rates were 167 and 81, respectively (penicillin g rate = 100), whereas ceftazidime hydrolysis was not detected. the nucleotide sequence revealed a bla gene related to that coding for ctx-m-3. despite 21 nucleotide substitutions, only 2 determined amino acid changes (ala27 ...200111158766
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