| computers and dental health education--a trial project at the liverpool garden festival. | | 2012 | 3297819 |
| electron microscopic structure of the "inclusion bodies" in pick's disease. | | 2014 | 4178657 |
| [achievements in urology in the ussr]. | | 2015 | 4592854 |
| homologous scleral explant buckles in retinal detachment surgery. | | 2015 | 4594665 |
| 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 ... | 2007 | 17824667 |
| 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 ... | 2006 | 16707334 |
| resistance and inactivation kinetics of bacterial strains isolated from the non-chlorinated and chlorinated effluents of a wwtp. | the microbiological quality of water from a wastewater treatment plant that uses sodium hypochlorite as a disinfectant was assessed. mesophilic aerobic bacteria were not removed efficiently. this fact allowed for the isolation of several bacterial strains from the effluents. molecular identification indicated that the strains were related to aeromonas hydrophila, escherichia coli (three strains), enterobacter cloacae, kluyvera cryocrescens (three strains), kluyvera intermedia, citrobacter freund ... | 2013 | 23924881 |
| molecular characteristics of extended-spectrum cephalosporin-resistant enterobacteriaceae from humans in the community. | to investigate the molecular characteristics of extended-spectrum cephalosporin (esc)-resistant enterobacteriaceae collected during a cross-sectional study examining the prevalence and risk factors for faecal carriage of extended-spectrum β-lactamase (esbl)-producing enterobacteriaceae in humans living in areas with high or low broiler density. | 2015 | 26029910 |
| 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 ... | 2006 | 16245080 |
| microbial diversity and dynamics during the production of may bryndza cheese. | diversity and dynamics of microbial cultures were studied during the production of may bryndza cheese, a traditional slovak cheese produced from unpasteurized ewes' milk. quantitative culture-based data were obtained for lactobacilli, lactococci, total mesophilic aerobic counts, coliforms, e. coli, staphylococci, coagulase-positive staphylococci, yeasts, fungi and geotrichum spp. in ewes' milk, curd produced from it and ripened for 0 - 10 days, and in bryndza cheese produced from the curd, in th ... | 2014 | 24291178 |
| 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 ... | 2006 | 16139515 |
| 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 ... | 2005 | 15920899 |
| 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 ... | 2005 | 15653915 |
| 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 ... | 2004 | 15477078 |
| bacteriophage ϕmam1, a viunalikevirus, is a broad-host-range, high-efficiency generalized transducer that infects environmental and clinical isolates of the enterobacterial genera serratia and kluyvera. | members of the enterobacterial genus serratia are ecologically widespread, and some strains are opportunistic human pathogens. bacteriophage ϕmam1 was isolated on serratia plymuthica a153, a biocontrol rhizosphere strain that produces the potently bioactive antifungal and anticancer haterumalide oocydin a. the ϕmam1 phage is a generalized transducing phage that infects multiple environmental and clinical isolates of serratia spp. and a rhizosphere strain of kluyvera cryocrescens. electron micros ... | 2014 | 25107968 |
| 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 ... | 2004 | 15128530 |
| 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 ... | 2003 | 12796820 |
| the use of chromogenic reference substrates for the kinetic analysis of penicillin acylases. | determination of kinetic parameters of penicillin acylases for phenylacetylated compounds is complicated due to the low k(m) values for these substrates, the lack of a spectroscopic signal, and the strong product inhibition by phenylacetic acid. to overcome these difficulties, a spectrophotometric method was developed, with which kinetic parameters could be determined by measuring the effects on the hydrolysis of the chromogenic reference substrate 2-nitro-5-[(phenylacetyl)amino]benzoic acid (ni ... | 1999 | 10542108 |
| a case of kluyvera cryocrescens peritonitis in a capd patient. | | 1996 | 8761550 |
| rapid burst kinetics in the hydrolysis of 4-nitrophenyl acetate by penicillin g acylase from kluyvera citrophila. effects of mutation f360v on rate constants for acylation and de-acylation. | the kinetics of release of 4-nitrophenol were followed by stopped-flow spectrophotometry with two 4-nitrophenyl ester substrates of penicillin g acylase from kluyvera citrophila. with the ester of acetic acid, but not of propionic acid, there was a pre-steady-state exponential phase, the kinetics of which were inhibited by phenylacetic acid (a product of hydrolysis of specific substrates) to the extent predicted from ki values. this was interpreted as deriving from rapid formation (73 mm-1.s-1) ... | 1996 | 8687381 |
| inactivation of penicillin acylase from kluyvera citrophila by n-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline: a case of time-dependent non-covalent enzyme inhibition. | penicillin acylase (pa) from kluyvera citrophila was inhibited by n-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (eedq), a specific carboxy-group-reactive reagent. enzyme activity progressively decreased to a residual value depending on eedq concentration. neither enzymic nor non-enzymic decomposition of eedq is concomitant with pa inactivation. moreover, enzyme re-activation is achieved by chromatographic removal of eedq, ph increase or displacement of the reagent with penicillin g. it was then ... | 1993 | 8489517 |
| characterization of an escherichia coli aromatic hydroxylase with a broad substrate range. | the hpab gene encoding an aromatic hydroxylase of escherichia coli atcc 11105, a penicillin g acylase-producing strain, has been cloned and expressed in e. coli k-12. this gene was located near the paca gene coding for penicillin g acylase. the hydroxylase has a molecular mass of 59,000 da, uses nadh as a cosubstrate, and was tentatively classified as a 4-hydroxyphenylacetic acid hydroxylase, albeit it exhibited a rather broad substrate specificity acting on different monohydric and dihydric phe ... | 1993 | 8458860 |
| changing the substrate specificity of penicillin g acylase from kluyvera citrophila through selective pressure. | escherichia coli (mut, mutd, leu-) cells transformed with plasmid pykd59 harbouring the pac gene encoding penicillin acylase (pa) from kluyvera citrophila atcc 21285 were exposed to environmental conditions that made expression of this enzyme essential for growth. under these conditions, spontaneous mutants were isolated that used adipyl-l-leucine as the sole source of l-leucine. dna sequencing of the mutant pac genes identified a transversion mutation of thymine to guanine at position 1163. thi ... | 1994 | 7980457 |
| new insights on the specificity of penicillin acylase. | in contrast with the general thought that penicillin g acylases (pgas) were only able to hydrolyse amides or esters of higly hydrophobic acids, we have demonstrated that the pga from kluyvera citrophila catalysed the hydrolysis of 4-nitrophenyl esters of acetic, propionic, butyric and valeric acids. values of kcat. and kcat./km were greatest for the first compound and less than values for benzylpenicillin by factors of 30 and 7, respectively. 4-nitrophenyl acetate was hydrolysed faster than 2-ni ... | 1995 | 7826381 |
| stabilization of heterodimeric enzyme by multipoint covalent immobilization: penicillin g acylase from kluyvera citrophila. | we have developed a strategy for immobilization-stabilization of penicillin g acylase (pga) from kluyvera citrophila by controlled multipoint covalent attachment to agarose-aldehyde gels. this enzyme is composed by two dissimilar subunits noncovalently bound. thus, in this article we establish clear correlations between enzyme stabilization and the multipoint immobilization and/or between enzyme stabilization and the involvement of the two subunits in the attachment of them to the support. we ha ... | 1993 | 18613049 |
| 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 ... | 2008 | 18625772 |
| 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 ... | 2010 | 20495273 |
| 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 ... | 2010 | 20567815 |
| 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 ... | 2011 | 21212944 |
| [kartagener's syndrome in two siblings]. | | 2005 | 1087624 |
| intra-osseous lipoma of the proximal part of the femur. case report. | | 2004 | 374417 |
| ultrathin (1 nm) vertically shadowed platinum-carbon replicas for imaging individual molecules in freeze-etched biological dna and material science metal and plastic specimens. | single molecule resolution in beam-sensitive, uncoated, noncrystalline materials has heretofore not been possible except in thin (less than or equal to 150 a) platinum-carbon (pt-c) replicas, which are resistant to electron beam destruction. previously, the granularity of metal film replicas limited their resolution to greater than or equal to 20 a. this paper demonstrates that pt-c film granularity and resolution are a function of the method of replication and other controllable factors. low-an ... | 2010 | 2809773 |
| [new research on the inhibitory action of methyl-3 hydroxy-6 quinazoline dione 2-4 on the cytodierese of plant cells. duration of the cell cycle and mitosis]. | | 2016 | 4802674 |
| identification and characterization of two novel bla(kluc) resistance genes through large-scale resistance plasmids sequencing. | plasmids are important antibiotic resistance determinant carriers that can disseminate various drug resistance genes among species or genera. by using a high throughput sequencing approach, two groups of plasmids of escherichia coli (named e1 and e2, each consisting of 160 clinical e. coli strains isolated from different periods of time) were sequenced and analyzed. a total of 20 million reads were obtained and mapped onto the known resistance gene sequences. as a result, a total of 9 classes, i ... | 2012 | 23056610 |
| structure mediation in substrate binding and post-translational processing of penicillin acylases: information from mutant structures of kluyvera citrophila penicillin g acylase. | penicillin acylases are industrially important enzymes for the production of 6-apa, which is used extensively in the synthesis of secondary antibiotics. the enzyme translates into an inactive single chain precursor that subsequently gets processed by the removal of a spacer peptide connecting the chains of the mature active heterodimer. we have cloned the penicillin g acylase from kluyvera citrophila (kcpga) and prepared two mutants by site-directed mutagenesis. replacement of n-terminal serine ... | 2015 | 26243007 |
| a new role for penicillin acylases: degradation of acyl homoserine lactone quorum sensing signals by kluyvera citrophila penicillin g acylase. | use of penicillin acylases for the production of semi-synthetic penicillins is well-known. escherichia coli penicillin g acylase (ecpga) has been extensively used for this purpose; however, kluyvera citrophila penicillin g acylase (kcpga) is assumed to be a better substitute, owing to its increased resilience to extreme ph conditions and ease of immobilization. in the present article we report a new dimension for the amidase activity of kcpga by demonstrating its ability to cleave bacterial quor ... | 2014 | 24564895 |
| cloning, overexpression, crystallization and preliminary x-ray crystallographic analysis of a slow-processing mutant of penicillin g acylase from kluyvera citrophila. | kluyvera citrophila penicillin g acylase (kcpga) has recently attracted increased attention relative to the well studied and commonly used escherichia coli pga (ecpga) because kcpga is more resilient to harsh conditions and is easier to immobilize for the industrial hydrolysis of natural penicillins to generate the 6-aminopenicillin (6-apa) nucleus, which is the starting material for semi-synthetic antibiotic production. like other penicillin acylases, kcpga is synthesized as a single-chain inac ... | 2013 | 23908045 |
| nosocomial bacteremia due to kluyvera cryocrescens: case report and literature review. | kluyvera cryocrescens infection has been considered rare; clinical features of k. cryocrescens bacteremia remain unclear because few reports have been published. we report a case of k. cryocrescens bacteremia in an adult male patient and review the literature. our case was one with nosocomial bacteremia in a patient with interstitial lung disease. the primary infection site was undetermined, although he had an indwelling peripheral intravenous catheter and a urinary catheter. piperacilin/tazobac ... | 2016 | 27051581 |
| psychophysical maps for subadditive dissimilarity ratings. | | 2013 | 3684491 |