concomitant high-level vancomycin and penicillin resistance in clinical isolates of enterococci.enterococci are important nosocomial pathogens among which resistance to multiple antibiotics is being recognized with increasing frequency. we characterized three clinical isolates from three new york city hospitals that demonstrated concomitant resistance to vancomycin (one vana, two vanb phenotypes) and high-level resistance to penicillin. two enterococcus faecium strains were intrinsically highly resistant to penicillin and showed very low affinity for penicillin of penicillin-binding protei ...19921562656
bacteremia due to beta-lactamase-producing enterococcus faecalis with high-level resistance to gentamicin in a child with wiskott-aldrich syndrome. 19921562666
selective intracellular lactate invisibility in enterococcus this article we will demonstrate that differences in hahn t2 relaxation of the 1h nmr signal from cytosolic and extracellular lactate can be exploited to monitor lactate concentration gradients in bacterial cells and provide information on lactate transport mechanisms. as a by-product of this study we have determined that there are at least three pools of lactate in bacterial cells with differing visibility in the nmr experiment. this has serious implications for the spectral editing techniqu ...19921569865
the hemolysin/bacteriocin produced by enterococci is a marker of pathogenicity.the hemolysin/bacteriocin produced by some strains of enterococcus faecalis is active in the lysis of human, rabbit, and horse erythrocytes, but not those from sheep. in this study, we determined that 20% of clinical enterococcal isolates tested in the clinical microbiology laboratory produced hemolysin and that pathogenic human e. faecalis were more likely to be hemolysin-producing isolates. among the organisms isolated from different anatomic sites, variability in the degree of hemolysin produ ...19921572135
characterization of culturability, protistan grazing, and death of enteric bacteria in aquatic ecosystems.nonstained bacteria (nsb), rhodamine-stained bacteria (rsb), and fluorescence-labeled bacteria (flb) were prepared from two enteric bacterial species, escherichia coli and enterococcus faecalis. counts of cfu of nsb and rsb and total numbers of rsb and flb were monitored over time, both in the presence and in the absence of natural microbiota. in the presence of natural microbiota, no differences were observed between cfu counts of nsb and rsb, but rsb total numbers were 1 to 4 orders of magnitu ...19921575503
aminoglycoside-resistant streptococcus and enterococcus species isolated from bovine mammary secretions.a total of 117 isolates representing four streptococcus species and 20 isolates representing two enterococcus species from bovine mammary secretions were examined for resistance to streptomycin, kanamycin, and gentamicin. resistance to streptomycin (85.4%) was most prevalent, followed by kanamycin (19%) and gentamicin (2.2%). minimum inhibitory concentration of streptomycin for most organisms examined ranged from 16 to 250 micrograms/ml. for kanamycin, the minimum inhibitory concentration for mo ...19921578037
contribution of the pad1-encoded cytolysin to the severity of experimental enterococcus faecalis endophthalmitis.the contribution of the pad1-encoded cytolysin to enterococcus faecalis virulence in an experimental endophthalmitis model was studied by using isogenic strains differing only in the location of transposon tn917. the course of experimental endophthalmitis in new zealand white rabbits was evaluated by postoperative reduction in retinal neuroresponsiveness, thin-section histopathology, and transmission electron microscopy. infections caused by cytolytic e. faecalis resulted in 99% loss of retinal ...19921587612
defective in vitro motility of polymorphonuclear leukocytes of homozygote and heterozygote chediak-higashi cats.the in vitro migratory responses of neutrophils of homozygote and heterozygote chediak-higashi cats were defective in an under-agarose assay when compared to the behavior of phagocytes of control cats. the linear distances traversed by the leading front of migrating chediak-higashi neutrophils toward streptococcal culture supernatant, zymosan-activated serum or buffer were reduced and smaller numbers of chediak-higashi phagocytes populated the resulting migration areas than did cells of control ...19921589952
antimicrobial susceptibility changes in enterococcus faecalis following various penicillin exposure regimens.penicillin-"virgin" strains of enterococcus faecalis collected from a population of individuals with no previous antibiotic exposure were subjected in vitro to penicillin delivered as repeated pulses, stepwise increasing concentrations, or sustained levels of a single concentration. changes in resistance to penicillin were assessed by determination of mics, and time-kill studies were performed to evaluate changes in tolerance to the bactericidal effects of penicillin. isogenic clones, derived fr ...19921590676
intrahospital spread of a single gentamicin-resistant, beta-lactamase-producing strain of enterococcus faecalis in argentina.six beta-lactamase-producing (bla+) isolates of enterococcus faecalis recovered over a 17-month period from an argentinian pediatric hospital were found to have identical or almost identical chromosomal restriction patterns by pulsed-field gel electrophoresis, although the plasmid patterns were different. these isolates, like bla+ enterococci in the united states, hybridized to a staphylococcal bla gene probe. the presence of a single strain was somewhat surprising, since all isolates transferre ...19921590694
comparison of ly264826-gentamicin with vancomycin-gentamicin against enterococci from blood cultures.the combination of the new glycopeptide ly264826 and gentamicin was compared with the combination of vancomycin and gentamicin against 30 strains of enterococci, comprising 20 strains of enterococcus faecalis, five strains of enterococcus faecium and five strains of enterococcus avium, isolated from blood cultures. ly264826 plus gentamicin was synergic against e. faecalis and e. faecium, but not against e. avium.19921592699
flavin-linked peroxide reductases: protein-sulfenic acids and the oxidative stress response.sequence analyses of the streptococcus faecalis nadh peroxidase and the flavoprotein component of the salmonella typhimurium alkyl hydroperoxide reductase indicate clear evolutionary links with members of the flavoprotein disulfide reductase family. however, chemical and spectroscopic evidence demonstrate that the non-flavin redox center in nadh peroxidase is an unusual stabilized cysteine-sulfenic acid (cys-soh) derivative, and not a cystine disulfide as found in the disulfide reductases. this ...19921595127
the clinical impact of culturing central venous catheters. a prospective study.the semiquantitative culture technique is a standard procedure for the laboratory diagnosis of catheter-associated infections and catheter-associated bacteremia. in a prospective observational study, we evaluated the clinical impact of the semiquantitative culture results on the treatment of the patient. clinical impact was defined as a change in diagnosis or therapy on the basis of the semiquantitative culture result. one hundred fifty-seven catheters consecutively submitted from the surgical i ...19921599360
the in-vitro antibacterial activity of a combination of cefpirome or cefoperazone with vancomycin against enterococci and staphylococcus aureus.cefpirome, cefoperazone and ceftazidime were tested for their in-vitro activity against enterococcus faecalis and methicillin-resistant staphylococcus aureus (mrsa) isolates. cefpirome was the most active cephalosporin followed by cefoperazone. ceftazidime had only very limited activity against these strains. in experiments with cefpirome/vancomycin and cefoperazone/vancomycin combinations, synergy was detected against most mrsa strains and some enterococci. antagonism did not occur.19921601753
microflora of the pouch of the koala (phascolarctos cinereus).microflora of the pouch epithelium of 17 female koalas (phascolarctos cinereus) were examined in relation to their current reproductive status and recent reproductive history. no microbial growth was observed in pouch swabs from 13 of 17 (76%) koalas, including four females without young, seven with pouch young and two with back young (i.e. permanently emerged from the pouch). growth of bacteria or yeasts was observed in pouch swabs from four koalas, each of which had experienced mortality of it ...19921602580
identification of new sex pheromone plasmids in enterococcus faecalis.we describe the identification of the following new sex pheromone plasmids in enterococcus faecalis: a haemolysin-bacteriocin plasmid, pip964; three r plasmids, pip1017, pip1438 and pip1440; and two cryptic conjugative plasmids, pip1141 and pmv120. the identification was based on the formation of cell aggregates on filter membranes during conjugation, on efficient transfer in broth matings, and on a positive clumping reaction of cells carrying these plasmids. in addition these plasmids hybridize ...19921603059
sex pheromone plasmid pad1-encoded surface exclusion protein of enterococcus faecalis.during conjugative transfer of sex pheromone plasmids of enterococcus faecalis a so-called surface exclusion protein reduces the frequency with which these plasmids are transferred to cells already possessing the same plasmid. we report here the dna sequence of a 3.8 kb fragment of the sex pheromone plasmid pad1 containing the structural gene sea1 for surface exclusion protein and a small open reading frame (orf) upstream of sea1. surface exclusion protein sea1 was found to be highly homologous ...19921603060
genetic basis of tetracycline resistance in clinical isolates of listeria monocytogenes.the genetic basis of tetracycline resistance was studied in 25 clinical isolates of listeria monocytogenes. resistance to tetracycline was associated with resistance to minocycline and due to the presence of the tet(m) gene in 24 strains. association of tet(m) with int-tn, the gene encoding the protein required for the movements of tn1545-like conjugative transposons, was found in all strains. cotransfer of tet(m) and int-tn among l. monocytogenes cells and from l. monocytogenes to enterococcus ...19921605611
conjugal transfer of plasmid dna from enterococcus faecalis to escherichia coli in digestive tracts of gnotobiotic mice.we have studied the transfer of the conjugative shuttle plasmid pat191, which confers resistance to kanamycin, from enterococcus faecalis to escherichia coli in the digestive tracts of six gnotobiotic mice. colonies of e. coli resistant to kanamycin were isolated from the feces of two mice, respectively, on days 25 and 35 after the beginning of the experiment and never thereafter. the transfer frequency of pat191, expressed as the number of transconjugants per donor cell isolated from intestines ...19921605622
determination of the chromosomal size of three different strains of enterococcus faecalis and one strain of enterococcus faecium.pulsed-field gel electrophoresis was used to determine the chromosomal size of three different strains of enterococcus faecalis and one strain of enterococcus faecium. the size determinations of og1x, a strain of e. faecalis widely used in many laboratories for genetic studies, using sma i, not i, and sfi i alone or in combination, ranged from 2,750 to 2,761 kb. using the same enzymes as with og1x, the size of hh-67, a plasmid-free clinical isolate of e. faecalis, was determined to be 2,170-2,28 ...19921605856
high-level resistance to gentamicin in enterococcus faecium.during a six-month period in a hospital in ireland, four patients were infected (isolation from blood cultures) and two were colonized (isolation from rectal swabs) with strains of enterococcus faecium highly resistant to gentamicin. mics of gentamicin were greater than 1000 mg/l for all six strains, and each possessed a plasmid of approximately 50 mda. resistance to gentamicin was transferable by conjugation from two of the six strains, and was associated with transfer of the 50 mda plasmid. th ...19921607328
[affinities of pbps of enterococci to cefepime and ampicillin].the beta-lactam resistance of genus streptococcus has been explained by the low binding affinity of penicillin-binding proteins (pbps) to the drug. this study was carried out to resolve the mechanisms of resistance to beta-lactam antibiotics in the species of genus enterococcus by means of binding affinities of pbps. streptococcus pyogenes, enterococcus faecalis, enterococcus faecium and enterococcus avium were employed as assay microbes. cefepime (cfpm) and ampicillin (abpc) were used as repres ...19921608172
the postantibiotic suppressive effect of l-ofloxacin, an optically active isomer of ofloxacin.the postantibiotic suppressive effect (pae) of l-ofloxacin was studied and compared with those of ciprofloxacin and norfloxacin. the pae of l-ofloxacin was observed against all gram-positive organisms tested: staphylococcus aureus, s. epidermidis, and enterococcus faecalis. at the achievable serum concentrations l-ofloxacin showed a longer pae than ciprofloxacin and norfloxacin. exposure of organisms to 4 micrograms/ml of l-ofloxacin for 2 hr produced a 3.1 and 4.2 hr pae for methicillin-sensiti ...19921611855
prostatitis--clinical and bacterial studies.forty men with clinical prostatitis were studied to determine the value of symptomatology and categorization and 30 (75%) were classified as having prostatitis on the basis of prostatic localization studies. of these 3 (10%) had chronic bacterial prostatitis, 18 (60%) had chronic abacterial prostatitis, and 9 (30%) had prostatodynia. no patient had acute bacterial prostatitis. although enterobacteriaciae were isolated from the 3 men with chronic bacterial prostatitis, these bacteria along with s ...19921616965
streptococcal and enterococcal bacteremia in patients with cancer.eighty-two episodes of bacteremia due to streptococci (including the genus enterococcus) in 78 patients hospitalized at institut jules bordet between 1986 and 1988 were reviewed. the incidence ranged from 5.5 to 7.6 per 1,000 admissions (16% of all bacteremias). enterococcus faecalis, streptococcus sanguis, and streptococcus mitis were the most prevalent isolates, followed by streptococcus angionosus, streptococcus salivarius, and large colony-forming beta-hemolytic species (a, b, c, and g). twe ...19921617072
nosocomial bacteremia due to enterococcus faecalis without endocarditis.during a 2-year observation period at a 2,200-bed university hospital, bacteremia due to enterococcus faecalis was observed in 111 patients. fifty-five patients with nosocomial bacteremia due to e. faecalis could be evaluated. the most common entry sites were the urinary tract (25%), the intraabdominal cavity (13%), and burn and decubital wounds (11%). bacteremia was preceded by administration of cephalosporins, imipenem, and aztreonam (n = 39); ciprofloxacin (n = 11); and other antibiotics (n = ...19921617073
enterococcal endocarditis.enterococci, most often enterococcus faecalis, cause 5%-20% of cases of infective endocarditis (ie). enterococcal ie is usually a disease of older men, and the most frequent source of infection is the genitourinary tract. in cases of enterococcal ie, both normal and previously damaged valves can be involved. the disease most commonly presents in a subacute fashion; clinical and laboratory features are similar to those observed with ie caused by other pathogens. diagnosis is based on the presence ...19921617074
[surgical treatment of active infective endocarditis and prosthetic valve endocarditis].fifteen patients with active native valve endocarditis (nve) and 5 with prosthetic valve endocarditis (pve) were subjected to this study. among the patients with nve, one of 10 with simple destruction of leaflets and 2 of 5 with annular infection died postoperatively of cerebral bleeding and persistent infection. five patients with annular infection, whose microorganisms were streptococcus faecalis, staphylococcus epidermidis and gram-negative coccus, had a shorter duration from onset to operati ...19921619816
stereotactic, angiography-guided clipping of a distal, mycotic intracranial aneurysm using the cosman-roberts-wells system: technical note.we describe the use of stereotactic, angiographic guidance for localization and clipping of a small, distal intracranial bacterial aneurysm. the technique uses the commercially available suetens-gybels-vandermeulen angiographic localizer with the widely used cosman-roberts-wells stereotactic system. this method is simple and easy to use and significantly decreased the operative time. it may be quite useful for surgically treating mycotic and other peripheral aneurysms.19921620306
nucleotide sequence and phylogeny of the tet(l) tetracycline resistance determinant encoded by plasmid pste1 from staphylococcus hyicus.the nucleotide sequence of the tetracycline resistance (tet) gene and its regulatory region, encoded by the plasmid pste1 from staphylococcus hyicus, was determined. the tet gene was inducible by tetracycline and encoded a hydrophobic protein of 458 amino acids. comparisons between the predicted amino acid sequences of the pste1-encoded tet from s. hyicus and the previously sequenced tet k variants from staphylococcus aureus, tet l variants from bacillus cereus, bacillus stearothermophilus, and ...19921622166
in vitro evaluation of e1077, a new cephalosporin with a broad antibacterial spectrum.e1077 is a novel parenteral cephalosporin with a wide spectrum of potent antibacterial activity against aerobic and anaerobic gram-positive and gram-negative bacteria. against methicillin-susceptible staphylococcus aureus, e1077 was twice as active as cefpirome, with an mic for 90% of strains tested (mic90) of 0.78 micrograms/ml. methicillin-resistant s. aureus was moderately to highly resistant to e1077, but e1077 was at least twice as active as other beta-lactams tested. against enterococcus f ...19921622167
the effect of resuscitation and the incubation-temperature on recovery of uninjured, heat injured and freeze injured enterococci.five strains of enterococci were inoculated on the slanetz and bartley enterococcus agar (ea), and incubated at 37 degrees c and 44 degrees c following: no injury, heat-injury and freeze-injury. the experiments were repeated introducing a 2 h resuscitation step in tryptic soy agar (tsa) at 37 degrees c and subsequent overlay with ea (tsa/ea) followed by incubation at both 37 degrees c and 44 degrees c. the tsa/ea method gave a significantly better recovery (1% confidence level) than the ea metho ...19921622754
nosocomial bacterial infections in very low birth weight infants.the occurrence of congenital and nosocomial bacterial septicaemia has been documented by identifying the number of positive blood cultures by reviewing the laboratory and clinical records of 394 very low birth weight infants who were consecutively admitted to a neonatal intensive care unit over a 40-month period. the incidence of congenital septicaemia was 6% and of nosocomial septicaemia 17%. the commonest causes of congenital infection were streptococcus agalactiae staphylococcus epidermidis a ...19921628675
detection of vancomycin resistance in enterococcus species.enterococcus faecalis and enterococcus faecium isolates that are resistant to vancomycin have recently been identified in north america and europe. of 155 clinical isolates of enterococci (113 e. faecium and 42 e. faecalis), we found that 98 were resistant, 52 were moderately susceptible, and 5 had intermediate susceptibilities to vancomycin by using broth microdilution susceptibility testing according to the national committee for clinical laboratory standards (nccls) (approved standard m7-a2). ...19921629315
influence of transient salivary flora on assessment of mutans streptococci level by the "strip mutans" method.the dentocult sm ("strip mutans") method occasionally shows decoloration of broth and of colonies of mutans streptococci on the plastic strip, thereby making interpretation difficult. in an attempt to explain the phenomenon and to investigate the influence of the salivary flora on the "strip mutans" method, a total of 46 subjects were sampled. saliva was analyzed using the "strip mutans" method and conventional plating techniques to identify mutans streptococci, enterococci, staphylococci, enter ...19921631483
hydrophobic interaction chromatography fractionates lipoteichoic acid according to the size of the hydrophilic chain: a comparative study with anion-exchange and affinity chromatography for suitability in species analysis.hydrophobic interaction chromatography fractionated the lipoteichoic acid of enterococcus faecalis into species of decreasing poly(glycerophosphate) chain length and decreasing extent of substitution with alpha-kojibiosyl residues (glcp alpha 1----2glcp alpha 1----). the chain length varied between 14 and 33 glycerophosphate residues per lipid anchor, the extent of glycosylation between 0.18 and 0.44 mol of alpha-kojibiosyl residues per mole of phosphorus, and, accordingly, the number of alpha-k ...19921632524
[an increased incidence of bacterial endocarditis in chronic inflammatory bowel diseases].of 92 consecutive patients treated for proven native valve endocarditis three had ulcerative colitis and 2 crohn's disease. all 5 patients developed severe complications; three had to undergo emergency valve replacement. with a prevalence of 64.1/10(5) cases of inflammatory bowel disease the calculated incidence (5/92) revealed a significant over-representation of inflammatory bowel disease among patients with proven endocarditis (p less than 5.08 x 10(-9)). possible explanations may be the supp ...19921636271
conditions modulating the ionic selectivity of transport by monensin examined on enterococcus hirae (streptococcus faecalis) by 23na-nmr and k+ atomic absorption.factors likely to modulate the ionic selectivity of monensin were examined on enterococcus hirae (streptococcus faecalis) in two states previously characterized: the resting (de-energized) cell and the active (energized) cell. internal and external na+ were followed by corresponding 23na-nmr resonances k+ concentrations were measured by atomic absorption. for a given cellular population of de-energized cells, the apparent transport rates and the final cationic concentrations reached at the stead ...19921637842
[studies of bacterial indicators for water pollution--growth of escherichia coli and enterococci in limited nutrient conditions].bacteria, that would be an ideal indicator for fecal contamination in environmental water, should not proliferate but at the same time should survive a little longer than enteropathogenic bacteria in the environmental water. while conventional methods have recommended escherichia coli as an indicator, enterococci is recommended as a preferable indicator for the estimation of fecal contamination based on the following observation. the relationship between the specific growth rate of organism and ...19921638040
evaluation of a mechanical/chemical infectious waste disposal system.the mechanical/chemical infectious waste disposal system (iwds), model z-5000 hc, manufactured by medical safetec inc. (indianapolis, indiana) was evaluated for its ability to disinfect biomedical waste.19921640095
transcriptional control of sex-pheromone-inducible genes on plasmid pad1 of enterococcus faecalis and sequence analysis of a third structural gene for (ppd1-encoded) aggregation substance.the expression of several neighbouring genes on plasmid pad1 that are necessary for conjugation depend on induction with sex pheromone cad1. analyses of transcripts by northern blot hybridization demonstrated that the genes sea1 (encoding surface exclusion protein) and asa1 (encoding aggregation substance) are transcribed independently. both genes are organized in different operons together with neighbouring open reading frames of unknown function. several transcripts could be identified for sea ...19921640831
enterococcus faecalis infection in a corneal graft. 19921642309
evaluation of bactec high blood volume resin media.bactec plus high-blood-volume resin media (aerobic bp 26 vial and anaerobic bp 27 vial) were compared with standard bactec media (aerobic nr 6a and anaerobic nr 7a vial). a total of 2253 blood culture sets, each consisting of the four vials, were collected. positive cultures were obtained from 403 sets and grew 428 organisms; 271 organisms were considered as significant. the bactec plus high blood volume resin (bp-hbv) media grew significantly more staphylococcus aureus, coagulase-negative staph ...19921643816
conjugative transposition of tn916 requires the excisive and integrative activities of the transposon-encoded integrase.transposon tn916 is a 16.4-kb broad-host-range conjugative transposon originally detected in the chromosome of enterococcus faecalis ds16. transposition of tn916 and related transposons involves excision of a free, nonreplicative, covalently closed circular intermediate that is substrate for integration. excisive recombination requires two transposon-encoded proteins, xis-tn and int-tn, whereas the latter protein alone is sufficient for integration. here we report that conjugative transposition ...19911648556
effect of daptomycin, metronidazole and mezlocillin combinations on mixed bacterial cultures involving facultative and anaerobic bacteria.the in vitro activities of different daptomycin concentrations in combination with metronidazole (4 mg/l) or/and mezlocillin (8 mg/l) were investigated on mixed bacterial cultures involving gram-positive facultative cocci. bacteroides fragilis group strains and escherichia coli. when streptococcus faecalis alone or together with e. coli was cultured with b. thetaiotaomicron the colony counts of the latter were 4 log units higher after incubation in the presence of daptomycin and metronidazole th ...19911649493
tn917 transposase. sequence correction reveals a single open reading frame corresponding to the tnpa determinant of tn3-family elements.a nucleotide sequence correction on the enterococcus faecalis transposon tn917 indicates that what was formerly thought to be two open reading frames (orf5 and orf6) is actually one reading frame (orf5). the latter exhibits homology with the tn3-family transposase determinants known as tnpa.19911650004
[therapeutic efficacy of imipenem/cilastatin sodium on respiratory tract infections in lung cancer patients].imipenem/cilastatin sodium (ipm/cs) was used to treat respiratory tract infections (rti) in 54 patients with lung cancer. out of the 54 patients studied, 53 were evaluable for the utility of ipm/cs; 42 had pneumonia, 9 had obstructive pneumonia, 1 had a lung abscess and 1 had acute bronchitis. the efficacy rate was 71.7%. seventeen causative organisms were isolated from 14 patients. they included staphylococcus aureus 5 strains, staphylococcus epidermidis 4 strains, staphylococcus sp. 2 strains, ...19911652653
mechanisms of clinical resistance to fluoroquinolones in enterococcus faecalis.about 10% of 100 clinical isolates of enterococcus faecalis were resistant to greater than or equal to 25 micrograms of norfloxacin, ofloxacin, ciprofloxacin, and temafloxacin per ml. in this study, the dna gyrase of e. faecalis was purified from a fluoroquinolone-susceptible strain (atcc 19433) and two resistant isolates, ms16968 and ms16996. strains ms16968 and ms16996 were 64- to 128-fold and 16- to 32-fold less susceptible, respectively, to fluoroquinolones than was atcc 19433; mics of nonqu ...19911656852
characterization of the gentamicin resistance transposon tn5281 from enterococcus faecalis and comparison to staphylococcal transposons tn4001 and enterococcus faecalis, the genetic determinant encoding gentamicin resistance (gmr) on the conjugative plasmid pbem10 previously has been shown to be on a mobile element. in the current study, this element, termed tn5281, was shown to relocate in the absence of homologous recombination in e. faecalis uv202. on the basis of restriction endonuclease analysis and dna-dna hybridization studies, tn5281 was shown to be similar, if not identical, to the gmr transposons tn4001 found in australian iso ...19911656854
transposon mutagenesis in staphylococcus epidermidis using the enterococcus faecalis transposon tn917.we transformed a clinical staphylococcus epidermidis isolate with the enterococcus faecalis transposon tn917-carrying plasmid ptv1. loss of plasmid replication was observed at 47 degrees c. tn917 transposes efficiently and apparently randomly. the transposition frequency could be stimulated by erythromycin. transposon mutagenesis in s. epidermidis provides a means for genetic study of the various virulence factors of this pathogen.19911657700
an integrative vector exploiting the transposition properties of tn1545 for insertional mutagenesis and cloning of genes from gram-positive bacteria.we have constructed and used an integrative vector, pat112, that takes advantage of the transposition properties (integration and excision) of transposon tn1545. this 4.9-kb plasmid is composed of: (i) the replication origin of pacyc184; (ii) the attachment site (att) of tn1545; (iii) erythromycin-and kanamycin-resistance-encoding genes for selection in gram- and gram+ bacteria; and (iv) the transfer origin of incp plasmid rk2, which allows mobilization of the vector from escherichia coli to var ...19911657722
conjugative transfer of tn916 in enterococcus faecalis: trans activation of homologous transposons.tn916 [carries tet(m)] is a 16.4-kb conjugative transposon that can establish itself in multiple copies in enterococcus faecalis. to study the interaction of coresident homologous transposons during conjugation, an e. faecalis mutant defective in homologous recombination was utilized for construction of strains harboring tn916 delta e (a derivative in which erm is substituted for tet) on the chromosome and tn916 on a nonconjugative plasmid. when these strains were used as donors, the two transpo ...19911657880
insertion of tn916 into bacillus pumilus plasmid pmgd302 and evidence for plasmid transfer by part of an effort to develop systems for genetic analysis of strains of bacillus pumilus which are being used as a microbial hay preservative, we introduced the conjugative enterococcus faecalis transposon tn916 into b. pumilus atcc 1 and two naturally occurring hay isolates of b. pumilus. b. pumilus transconjugants resistant to tetracycline were detected at a frequency of approximately 6.5 x 10(-7) per recipient after filter mating with e. faecalis cg110. southern hybridization confirmed the ...19911658832
pharmacodynamics of daptomycin and vancomycin on enterococcus faecalis and staphylococcus aureus demonstrated by studies of initial killing and postantibiotic effect and influence of ca2+ and albumin on these drugs.the pharmacodynamics of daptomycin and vancomycin on enterococcus faecalis atcc 29212 and staphylococcus aureus atcc 25923 were investigated by studying the postantibiotic effect (pae) and initial killing. the influence of ca2+ and albumin on these drugs was also evaluated. the pae was studied by use of bioluminescence assay of bacterial atp. daptomycin at clinically achievable concentrations produced a dose-dependent pae on e. faecalis (0.6 to 6.7 h) and s. aureus (1.0 to 6.3 h). the long pae o ...19911659305
cloning and nucleotide base sequence analysis of a spectinomycin adenyltransferase aad(9) determinant from enterococcus faecalis.enterococcus faecalis ldr55, a human clinical isolate, is resistant to tetracycline (tcr), erythromycin (emr), and high levels (greater than 2,000 micrograms/ml) of spectinomycin (spr) but not streptomycin. filter matings between strain ldr55 and e. faecalis og1-rf produced transconjugants with the following resistance phenotypes: tcr emr spr, tcr emr, tcr spr, and tcr only but never emr or spr only. the genetic determinant encoding resistance to spectinomycin was cloned in streptococcus sanguis ...19911659306
transposon tn916 mutagenesis in clostridium botulinum.the study of toxinogenesis and other properties in clostridium botulinum is limited by the absence of genetic methods that enable construction of defined mutants. in this study, tetracycline-resistant transposon tn916 in enterococcus faecalis was conjugatively transferred in filter matings to group i clostridium botulinum strains hall a and 113b. the tn916 transfer frequencies to c. botulinum ranged from 10(-8) to 10(-5) tcr transconjugant per recipient depending on the donor strain. southern bl ...19911660696
a phase variation event that activates conjugation functions encoded by the enterococcus faecalis plasmid pad1.enterococcus faecalis cells carrying the conjugative plasmid pad1 undergo several related changes when induced by the sex pheromone cad1. included are the production of novel surface proteins, the formation of cellular aggregates in broth cultures, the ability to transfer the plasmid at high frequency in broth matings, and the change from a soft to a "dry" colony morphology. spontaneous, constitutively dry colony (dryc) variants of e. faecalis (pad1) were found to arise at a frequency of 10(-4)- ...19911661426
characterization of a region of the enterococcus faecalis plasmid pam beta 1 which enhances the segregational stability of pam beta 1-derived cloning vectors in bacillus subtilis.the nucleotide sequence of a 2.13-kb ecori-hindiii, pam beta 1-derived fragment, isolated from the gram-positive cloning vector phv1431, has been determined and shown to encode two orfs. orf h encodes for a protein of 23,930 da which exhibits substantial homology to bacterial site-specific recombinases, particularly the resolvases of the gram-positive transposons tn917 (30.3% identity) and tn552 (31.6% identity) and the clostridial plasmid pip404 (27.1% identity). the second orf (i) is incomplet ...19911661428
[an electron microscopic study of the interaction of bacterial intestinal microflora and rotavirus virions].transmission electron microscopy has revealed the capacity of rotaviruses for adsorption on escherichia coli, klebsiella pneumoniae, proteus mirabilis cells and the absence of such capacity with respect to enterococcus faecalis, lactobacillus casei and edwardsiella tarda. different degrees and a varying character of the adsorption of rotaviruses by the representatives of the opportunistic group of bacteria have been established, which may aggravate the course of rotavirus diarrhea due to the agg ...19911661985
chromosomal integration of plasmid dna by homologous recombination in enterococcus faecalis and lactococcus lactis subsp. lactis hosts harboring tn919.integration of pci192, a pbr322-derived vector plasmid containing homology to the chromosomally located conjugative transposon tn919 was observed in two strains that harbor tn919, namely, enterococcus faecalis gf590 and lactococcus lactis subsp. lactis ch919. hybridization analysis indicated that single-copy integration of the plasmid had occurred at low frequency. the tn919::plasmid structure was conjugated from an e. faecalis donor to a l. lactis recipient, although at lower frequencies than w ...19911662938
conjugal transfer of tn916, tn916 delta e, and pam beta 1 from enterococcus faecalis to butyrivibrio fibrisolvens strains.anaerobic filter matings of butyrivibrio fibrisolvens h17c, cf3, d1, or gs113, representing different dna relatedness groups, were done with enterococcus faecalis cg110, which contains chromosomally inserted tn916. tetracycline-resistant transconjugants were obtained with each mating pair at average frequencies of 4.4 x 10(-6) (per recipient) and 5.2 x 10(-6) (per donor). the transfer frequencies of tn916 into b. fibrisolvens varied 5- to 10-fold with mating time, strain, and growth stage. by us ...19911662939
introduction of tn916 and pam beta 1 into streptococcus bovis jb1 by conjugation.the transposon tn916 and self-mobilizing plasmid pam beta 1 were conjugated from enterococcus faecalis to the ruminal bacterium streptococcus bovis jb1. transconjugants were identified by resistance to tetracycline (tn916) or erythromycin (pam beta 1) and by southern hybridization analyses. transfer frequencies were 7.0 x 10(-6) and 1.0 x 10(-6) per recipient cell for tn916 and pam beta 1, respectively. the transconjugants jb1/tn916 and jb1/pam beta 1 were used as donors for matings with e. faec ...19911662940
in-vitro activity of temafloxacin for gram-positive pathogens.the antimicrobial activity of temafloxacin against aerobic gram-positive cocci was compared to that of ciprofloxacin, ofloxacin, fleroxacin and pefloxacin using the broth microdilution technique. temafloxacin was more active than the other four fluoroquinolones, particularly for viridans streptococci and streptococcus pneumoniae. the mic90 of temafloxacin was at least four-fold lower than that of ciprofloxacin and ofloxacin for viridans streptococci and penicillin-susceptible pneumococci. the mi ...19911664835
in vitro activity of sparfloxacin and six reference antibiotics against gram-positive bacteria.the in vitro activity of sparfloxacin, a new fluoroquinolone, was assessed against 234 gram-positive bacterial isolates by agar dilution (10(4) cfu/spot). sparfloxacin activity was compared with that of ciprofloxacin and five other antibiotics. sparfloxacin was the most active drug tested against methicillin-sensitive and methicillin-resistant staphylococcus aureus (mrsa) and coagulase-negative staphylococci (mic90, 0.125-0.25 mg/l). sparfloxacin was also the most active drug tested against ente ...19911665123
in vitro activity of sparfloxacin (ci-978, at-4140, and pd 131501). a quinolone with high activity against gram-positive bacteria.sparfloxacin (ci-978, at-4140 and pd 131501) is a new antimicrobial agent of the piperazinyl quinolone class. relative to other quinolones, it is a potent antistaphylococcal and antistreptococcal drug in vitro: the microbroth 90% minimum inhibitory concentration (mic90) (in microgram/ml) was 0.25 vs 26 methicillin-resistant and -sensitive coagulase-positive and -negative staphylococci and 20 streptococcus pneumoniae; 0.5 vs 20 strains each of s. pyogenes, s. agalactiae, and enterococcus faecalis ...19911665775
[in vitro bactericidal effect of temafloxacin and tosufloxacin against streptococci].tosufloxacin tosylate (tosu) and temafloxacin hydrochloride (tema) were tested in vitro against 248 clinical isolates of various species of streptococci recovered in a hospital microbiology laboratory (bellevue regional teaching hospital). species included s. pneumoniae (n = 20), group a streptococci (n = 22), group b streptococci (n = 30), group g streptococci (n = 17), group d s. bovis (n = 19), enterococcus faecium (n = 45), enterococcus faecalis (n = 28), s. sanguis (n = 21), s. milleri (n = ...19911666667
[in vitro effect of new fluoroquinolones and betalactamines combinations against enterococci].combinations of one of the new fluoroquinolones (ciprofloxacin, temafloxacin or tosufloxacin) with a betalactam (amoxicillin, piperacillin, or imipenem) were tested in vitro using the checkboard method against 28 strains of streptococcus faecalis recovered in 1990 from a variety of specimens. no instance of antagonism (fic greater than 2) was recorded. effects of the two agents were usually additive (0.5 less than fic less than or equal to 1). an indifferent effect (1 less than fic less than or ...19911666668
a host factor absent from lactococcus lactis subspecies lactis mg1363 is required for conjugative matings between lactococcus lactis strains, the conjugative transposons tn916 and tn919 are found in the chromosome of the transconjugants in the same place as in the chromosome of the donor, indicating that no transposition has occurred. in agreement with this, the frequency of l. lactis transconjugants from intraspecies matings is the same whether the donor contains the wild-type form of the transposon or the mutant tn916-int1, which has an insertion in the transposon's integrase gene. howe ...19911667220
[bacteremia caused by vancomycin-resistant enterococcus faecalis. report of 2 cases].the rising concern about nosocomial bacteremia due to vancomycin-resistant e. faecalis in spanish hospitals. retrospective review of the medical records of two patients with nosocomial bacteremia due to e. faecalis resistant to vancomycin. both patients (a 78 years-old male and a 65 years-old female) were admitted in two separate hospital units. none of them had been previously treated with vancomycin, and both patients had severe underlying diseases. the two strains isolated showed high-level v ...19911668361
comparative analysis of enterococcus faecalis sex pheromone plasmids identifies a single homologous dna region which codes for aggregation analysis of the 11 known sex pheromone plasmids of enterococcus faecalis was performed by dna-dna hybridization. plasmids pad1, pjh2, and pbem10 turned out to be closely related, whereas pam373 showed only weak homology with pad1. a comparison of the hemolysin/bacteriocin determinants of pad1, pjh2, and pob1 revealed strong similarities at the dna level. our main finding was that one dna region is conserved among all sex pheromone plasmids, with pam373 again being an exception; for pad1 this ...19911673459
resistance of enterococcus faecium to vancomycin and gentamicin. 19911675750
cloning, sequencing, and expression in escherichia coli of a streptococcus faecalis autolysin.a streptococcus faecalis genomic bank was obtained by partial digestion with mboi and cloning into the sali restriction site of ptz18r. screening of about 60,000 escherichia coli transformants for cell wall lysis activity was done by exposing recombinant colonies grown on medium containing lyophilized micrococcus lysodeikticus cells to chloroform and toluene vapors in order to release proteins. because this procedure provoked cell death, colonies could not be used directly for transformant recov ...19911679432
the fluoroquinolones exert a reduced rate of kill against enterococcus faecalis.the bactericidal activities of ciprofloxacin, ofloxacin and dr-3355 have been investigated against enterococcus faecalis, staphylococcus aureus and staphylococcus epidermidis over 24 h. the three fluoroquinolones were found to be rapidly bactericidal against the staphylococci, killing over 99% of the bacteria during the first 3 h of exposure with a further reduction in viability of approximately one logarithm occurring over the next 21 h. in contrast, the fluoroquinolones displayed a much slower ...19911682462
the killing activity of microwaves on some non-sporogenic and sporogenic medically important bacterial strains.the killing activity of microwaves of 2450 mhz frequency and 325 w, 650 w and 1400 w power on some bacterial strains was investigated. vegetative strains of staphylococcus aureus, streptococcus pyogenes group a, escherichia coli, pseudomonas aeruginosa and enterococcus faecalis and spores of bacillus subtilis and bacillis stearothermophilus in aqueous suspensions were exposed to 325 w and 650 w waves for different lengths of time. enterococcus faecalis and spores of b. subtilis and b. stearother ...19911686036
influence of phagosomal contents on the apparent inhibition of phagosome-lysosome fusion mediated by polyanionic substances in mouse peritoneal macrophages.the study of fusion of phagosomes with secondary lysosomes in macrophages is facilitated by assessing transfer of fluorescent or electron-opaque markers (or both) from the lysosomes to the phagosomes. when certain virulent viable pathogens are phagocytosed by mouse peritoneal macrophages, phagosome-lysosome fusion (p-lf) is inhibited. nonviable counterparts ordinarily cannot impose this block. a similar, but spurious, block to p-lf seems to be mediated from the lysosomal domain following sequest ...19901693519
[the detection of streptococcal cell-wall proteins that form complexes with human macroglobulins].the composition of the extracts of the cultures of individual streptococcal strains, studied by immunoblotting techniques, has been shown to contain proteins with a molecular weight of 70-80 kd. these proteins have pronounced affinity to human macroglobulins: alpha-macroglobulin, alpha-glycoprotein associated with pregnancy and protein a. the significance of this phenomenon on the cellular and somatic levels is discussed.19901700566
induction of autolysis in enterococcus faecalis s-47 by peptide addition to its bactericidal mode of action, the peptide antibiotic as-48 exhibits a bacteriolytic effect on enterococcus faecalis s-47 that is associated with autolysin activation. bacteriolysis induced by the antibiotic can be modulated by addition of edta, divalent cations and autolysin activators (trypsin) or inhibitors (cardiolipin), suggesting that topologic regulation of the autolysins is involved in the process. in addition, inhibitors of protein and rna synthesis interfere markedly w ...19901700974
permeation of bacterial cells, permeation of cytoplasmic and artificial membrane vesicles, and channel formation on lipid bilayers by peptide antibiotic as-48.peptide as-48 induces ion permeation, which is accompanied by the collapse of the cytoplasmic membrane potential, in sensitive bacteria. active transport by cytoplasmic membrane vesicles is also impaired by as-48. at low concentrations, this peptide also causes permeability of liposomes to low-molecular-weight compounds without a requirement for a membrane potential. higher antibiotic concentrations induce severe disorganization, which is visualized under electron microscopy as aggregation and f ...19911702784
phylogenetic analysis of streptococcus saccharolyticus based on 16s rrna sequencing.reverse transcriptase sequencing of 16s rrna of streptococcus saccharolyticus was performed in order to determine the phylogenetic position of this organism. on the basis of the sequence data streptococcus saccharolyticus formed a distinct group with enterococcus faecalis (type species of the genus enterococcus) and other enterococcal species. streptococcus saccharolyticus was found to be only distantly related to members of the genus streptococcus sensu stricto. it is therefore proposed that st ...19901703505
classification and identification of bacteria by fourier-transform infrared spectroscopy.this study describes a computer-based technique for classifying and identifying bacterial samples using fourier-transform infrared spectroscopy (ft-ir) patterns. classification schemes were tested for selected series of bacterial strains and species from a variety of different genera. dissimilarities between bacterial ir spectra were calculated using modified correlation coefficients. dissimilarity matrices were used for cluster analysis, which yielded dendrograms broadly equated with convention ...19911710644
[the range of antigenic specificity of bifidobacterium peptidoglycan].the antigenic relationships of bifidobacterium bifidum 1 peptidoglycans with different strains of this species (lva-3, 791, go-4), bifidobacteria of other species (b. adolescentis go-13, b. breve 79-38, b. lactentis 79-41, b. longum go-3) and bacteria of remote taxonomic groups (streptococcus faecalis 6-3. staphylococcus aureus com 885, s. epidermidis com 2124. lactobacillus plantarum 1, escherichia coli m-17) were studied on the basis of a highly sensitive test system permitting the registratio ...19911716036
relationship of the chemical structure and immunobiological activities of lipoteichoic acid from streptococcus faecalis (enterococcus hirae) atcc 9790.two molecular species of lipoteichoic acid (lta 1 and lta 2) were isolated from whole cells of streptococcus faecalis (enterococcus hirae) atcc 9790 by hydrophobic chromatography on octyl sepharose cl-4b. chemical analysis revealed that lta 1 and lta 2 contained two and four acyl lipid anchors respectively. lta 1 was less active than lta 2 in inducing cytokines, except interleukin-1 (il-1), but their in vivo antitumour effects were similar. lta 2 was a potent inducer of tumour necrosis factor (t ...19911718341
cloning, sequence and overexpression of nadh peroxidase from streptococcus faecalis 10c1. structural relationship with the flavoprotein disulfide reductases.dna fragments encoding streptococcal nadh peroxidase (npxase) have been amplified, cloned and sequenced from the genome of streptococcus (enterococcus) faecalis 10c1 (atcc 11700). the npxase gene (npr) comprises 1341 base-pairs and is preceded by a typical ribosome binding site. upstream from the structural gene, putative -10 and -35 promoter regions have been identified, as has a possible factor-independent terminator that occurs in 3'-flanking sequences. the deduced relative molecular mass (mr ...19911719212
[kinetics of bacterial wash-out in the haemonetics cell saver iii].autologous, outdated blood units were inoculated with four types of bacteria--pseudomonas aeruginosa, escherichia coli, streptococcus faecalis, staphylococcus aureus--in two concentrations (10e4, 10e6) to test the effect of the washing procedure (cell saver iii haemonetics) on the elimination of bacteria. the elimination rate ranged from 17% (streptococcus faec. 10e4) to 96% (pseudomonas aer. 10e6). these results confirm the routine use of wash centrifuge systems (type cell saver) to process she ...19911725651
addition of cetyl pyridinium chloride to histological demineralizing agents to improve the demonstrability of gram-positive has previously been shown experimentally using s. faecalis that the relative number of gram-positive bacteria is reduced by demineralizing agents. to achieve better bacterial preservation after demineralization, cetyl pyridinium chloride (cpc) and neutral formaldehyde solution (nf) were added, separately and in combination, to formic acid and edta. the number of s. faecalis organisms in suspension was determined using a haemocytometer, and the percentage of gram-positive bacteria was ascertai ...19911725981
the cumulative effect of disinfection, storage, histological fixation and demineralization on number and staining ability of gram-positive has previously been shown experimentally using s. faecalis that the relative number of blue-staining gram-positive bacteria was reduced by demineralizing agents as well as by disinfection (wijnbergen & van mullem 1987, van mullem & wijnbergen 1989). in this study the cumulative effect of disinfection, experimental period, fixation and demineralization was investigated. the use of additives to the fixative and the demineralizing agents to limit the loss of blue-staining bacteria was also studi ...19911725982
aggregation substance of enterococcus faecalis mediates adhesion to cultured renal tubular cells.the sex pheromone system of enterococcus faecalis is a unique, highly efficient plasmid collection mechanism for this species. a crucial role in this system is played by an adhesin called aggregation substance which enables the cell-cell contact between donor and recipient strains. the existence of the amino acid motif arg-gly-asp-ser in the adhesin prompted us to look for a possible binding of e. faecalis cells expressing aggregation substance to eucaryotic cells. we were able to show that the ...19921729187
isolation and characterisation of the pyruvate dehydrogenase complex of anaerobically grown enterococcus faecalis nctc this contribution the isolation and some of the structural and kinetic properties of the pyruvate dehydrogenase complex (pdc) of anaerobically grown enterococcus faecalis are described. the complex closely resembles the pdc of other gram-positive bacteria and eukaryotes. it consists of four polypeptide chains with apparent molecular masses on sds/page of 97, 55, 42 and 36 kda, and these polypeptides could be assigned to dihydrolipoyl transacetylase (e2), lipoamide dehydrogenase (e3) and the t ...19921730230
infections due to beta-lactamase-producing, high-level gentamicin-resistant enterococcus investigate the risk factors, clinical features, molecular epidemiology, and treatment outcomes associated with an outbreak of infections due to beta-lactamase-producing, high-level gentamicin-resistant enterococcus faecalis.19921733382
active-site structural comparison of streptococcal nadh peroxidase and nadh oxidase. reconstitution with artificial flavins.the apoproteins of the streptococcal nadh peroxidase (h2o2----2h2o) and nadh oxidase (o2----2h2o) stabilize the neutral forms of 6-hydroxy- and 6-mercapto-fad, respectively. the redox behavior of the 6-hydroxy-fad peroxidase closely mimics that of the native enzyme with both dithionite and nadh. both oxidase and peroxidase preferentially stabilize the n(1)-protonated p-quinonoid species of 8-mercapto-fad, and the 8-position of the bound flavin is accessible to solvent in both proteins. the 8-mer ...19921740431
bacteriological nasal flora in newborns indicating health and/or development of infection.during delivery, a fetus otherwise sterile during the intrauterine life, comes in contact with bacterial flora of the mother's birth canal, and then also with the ward personnel's skin and respiratory system flora. due to the absence of competitive bacteriological flora, the nasal cavity is gradually colonized by microorganisms, especially those with a capacity of adhesion to epithelial cells of respiratory nasal mucosa. bacteriological flora of the newborn's nasal flora was observed on days 1 a ...19911743875
is primary sensitivity testing on urine samples valid?one thousand eight hundred urine specimens were examined prospectively to determine the validity of primary sensitivity testing. microscopic criteria assessing pyuria and microorganisms were developed for predicting the presence of urinary tract infection and thus suitability for direct sensitivity testing. the criteria selected gave a positive predictive value of 74.6% and a negative predictive value of 99.5%. zone diameters by primary and standardized secondary methods were compared for each u ...19911745566
[the effect of various culture parameters on the yield of restriction endonuclease sfa ni].a simple technique is proposed for testing the restriction endonuclease sfa ni activity in lysates of streptococcus faecalis cells. the technique was used to study the effect of inorganic phosphate and the growth phase on the enzyme yield. conditions were chosen that provide a high yield of the sfa ni activity and a significantly reduced level of nucleases in the cells.19911745646
in vitro activity of the novel cephalosporin gr69153.the in vitro activity of gr69153 was compared to that of ceftazidime, ceftriaxone, imipenem and gentamicin against a total of 702 recent clinical isolates. mics were determined by a standard agar dilution procedure and two inocula (10(4) and 10(8) cfu) were used throughout. gr69153 inhibited 90% of isolates of escherichia coli, klebsiella pneumonia and proteus mirabilis at less than or equal to 0.25 mg/l and 90% of isolates of pseudomonas aeruginosa at less than or equal to 1 mg/l. citrobacter f ...19911748126
structural organization of the corynebacterium glutamicum plasmid pcg100.pcg100, a 3 kb cryptic plasmid of corynebacterium glutamicum atcc 13058, probably identical with psr1 from c. glutamicum atcc 19223, was characterized. the minimum region for autonomous replication was shown to be contained on a 1.9 kb bglii-ncoi fragment; a 380 bp hindiii-sphi fragment can replicate in the presence of the parental plasmid, which presumably provides a trans-acting replication factor. derivatives of pcg100 are able to replicate in several corynebacterium, brevibacterium and arthr ...19911748866
low cost device for electrotransformation and its application to the highly efficient transformation of escherichia coli and enterococcus faecalis.a simple, low cost device for electrotransformation has been designed and constructed. the cost of the circuit was only $150. maximum field strength of 12,000 v/cm with an actual time constant up to 11 msec was obtained with a newly designed circuitry and a 0.1-cm electrode gap cuvette. eschericia coli strains dh1, dh5 alpha, and le392 were transformed at an efficiency of 10(9)/micrograms dna with plasmids puc18 and pbr322. e. faecalis strain og1x was transformed at an efficiency of 0.9 x 10(5)/ ...19911749819
streptococcus faecalis in neonatal infective endocarditis. 19911753124
evaluation of the vitek gps-ta card for laboratory detection of high-level gentamicin and streptomycin resistance in enterococci.the vitek gps-ta card (vitek systems, hazelwood, mo.) was compared with single-concentration broth microdilution and disk diffusion methods using high-content disks for the detection of high-level resistance to gentamicin and streptomycin in 99 isolates of enterococci (81 enterococcus faecalis isolates and 18 enterococcus faecium isolates). the gps-ta card accurately detected high-level resistance to gentamicin, but not streptomycin, in e. faecalis. when streptomycin is being considered for ther ...19911757562
[the characteristics of staphylococcus aureus peptidoglycan in the spectrum of the reactivity of human lymphocytes to bacterial peptidoglycans].the sensitivity of lymphocytes of healthy persons to s. aureus peptidoglycan as compared with that to the polyclonal stimulator zymosan c3b and peptidoglycans of other bacteria (streptococcus faecalis, escherichia coli, bacterium bifidum) was analyzed with a test system permitting the determination of specific reactivity to peptidoglycans. the analysis showed that at the peak of luminol-dependent chemiluminescence (25-30 minutes) individual reactivity to s. aureus peptidoglycan varied within wid ...19911759526
amperometric monitoring of bacteria-induced milk acidity using a platinum disc microelectrode.the acidity induced by the action of bacteria in milk samples was monitored amperometrically by using a platinum microelectrode. the measurements were performed directly on commercial packs of milk, stored at 32 degrees c, and were continued for 9-10 d after inoculation. the data were compared with those obtained by measuring the ph of the samples and the results are discussed on the basis of the metabolism of each bacterial species. the effects of the following bacteria were examined: staphyloc ...19911759720
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