| an atpase operon involved in copper resistance by enterococcus hirae. | | 1992 | 1288347 |
| cloning and disruption of a putative nah-antiporter gene of enterococcus hirae. | when growing in a sodium-rich environment, wild-type enterococcus hirae extrudes sodium by two mechanisms, atp-driven sodium extrusion, and nah-antiport. mutant 7683 is unable to grow on sodium-rich media. this is due to two mutations, one inactivating atp-driven sodium transport and a second rendering nah-antiport inoperative. 7683 was transformed by electroporation with a gene bank, derived from e. hirae, in an escherichia coli-e. hirae shuttle vector. transformants which had regained the abil ... | 1992 | 1312090 |
| natural occurrence of structures in oral streptococci and enterococci with dna homology to tn916. | seventeen oral streptococci and 18 enterococci were tested for the presence of dna sequences homologous to the conjugative transposon tn916 encoding tetracycline resistance. all the strains were resistant to tetracyclines, including minocycline, and most of them were resistant to other antibiotics. tn916-like structures, identified by hybridization of hincii-digested dna, were found on the chromosomes of 11 oral streptococci and four enterococci and on two plasmids, pip1549 and pip1440, one harb ... | 1992 | 1317150 |
| the putative na+/h+ antiporter (napa) of enterococcus hirae is homologous to the putative k+/h+ antiporter (kefc) of escherichia coli. | two monovalent ion porters, the putative na+/h+ antiporter (napa) of enterococcus hirae and the putative k+/h+ antiporter (kefc) of escherichia coli, are similar in sequence throughout their hydrophobic domains. these two proteins, which comprise a novel family of transporters unrelated to the previously characterized na+/h+ exchangers of e. coli (nhaa and nhab) are proposed to function by essentially the same mechanism. | 1992 | 1325937 |
| gene structure of enterococcus hirae (streptococcus faecalis) f1f0-atpase, which functions as a regulator of cytoplasmic ph. | enterococcus hirae (formerly streptococcus faecalis) atcc 9790 has an f1f0-atpase which functions as a regulator of the cytoplasmic ph but does not synthesize atp. we isolated four clones which contained genes for c, b, delta, and alpha subunits of this enzyme but not for other subunit genes. it was revealed that two specific regions (upstream of the c-subunit gene and downstream of the gamma-subunit gene) were lost at a specific site in the clones we isolated, suggesting that these regions were ... | 1992 | 1328152 |
| cloning and sequence analysis of the muramidase-2 gene from enterococcus hirae. | extracellular muramidase-2 of enterococcus hirae atcc 9790 was purified to homogeneity by substrate binding, guanidine-hcl extraction, and reversed-phase chromatography. a monoclonal antibody, 2f8, which specifically recognizes muramidase-2, was used to screen a genomic library of e. hirae atcc 9790 dna in bacteriophage lambda gt11. a positive phage clone containing a 4.5-kb dna insert was isolated and analyzed. the ecori-digested 4.5-kb fragment was cut into 2.3-, 1.0-, and 1.5-kb pieces by usi ... | 1992 | 1347040 |
| modular design of the enterococcus hirae muramidase-2 and streptococcus faecalis autolysin. | the mature forms of the extracellular muramidase-2 of enterococcus hirae and streptococcus faecalis autolysin have very similar primary structures. each consists of an active-site-containing n-terminal domain fused to a multiple-repeat c-terminal domain. polypeptide segments occurring at equivalent places in these two bacterial wall lytic enzymes have homologues in two phage lysozymes and in three functionally unrelated proteins, illustrating the principle that protein molecules frequently are c ... | 1992 | 1352512 |
| the autolytic ('suicidase') system of enterococcus hirae: from lysine depletion autolysis to biochemical and molecular studies of the two muramidases of enterococcus hirae atcc 9790. | autolysis of enterococcus hirae atcc 9790 is the result of the action of endogenous enzymes that hydrolyze bonds in the protective and shape-maintaining cell wall peptidoglycan. it is thought that these potentially suicidal enzymes play a positive role(s) in wall growth and division and are expressed as autolysins when cell wall assembly and/or repair are inhibited. e. hirae possesses two potentially autolytic enzymes, both of which are muramidases. although they hydrolyze the same bond as hen e ... | 1992 | 1362171 |
| diarrhea caused by a slow-growing enterococcus-like agent in neonatal rats. | an enteropathogenic enterococcus-like agent was isolated from a spontaneous outbreak of diarrhea that occurred in a colony containing neonatal rats. diarrhea was experimentally reproduced in virus-antibody-free neonatal rats inoculated with this purified "enterococcus." gram-positive cocci were adhered to the small intestinal villi of affected animals from which the organism was reisolated. the isolate's classification in the genus enterococcus was confirmed by genetic probe; however, because of ... | 1992 | 1479804 |
| production of bacteriocin inhibitory to listeria species by enterococcus hirae. | a bovine intestinal bacterial isolate, identified as enterococcus hirae, was found to produce a bacteriocin (designated hiraecin s) inhibitory to listeria monocytogenes and other listeria spp. identification to species level was determined by comprehensive biochemical and morphological tests which were verified by dna-dna homology assays. the antimicrobial agent was inactivated by pronase and papain and was insensitive to catalase. the antimicrobial activity was not due to hydrogen peroxide or a ... | 1992 | 1482176 |
| enterococcus hirae in septicaemia of psittacine birds. | | 1992 | 1496756 |
| macrophage response to bacteria: induction of marked secretory and cellular activities by lipoteichoic acids. | lipoteichoic acids (ltas) from various bacterial species, including staphylococcus aureus, streptococcus pyogenes, streptococcus pneumoniae, enterococcus faecalis, and listeria monocytogenes, were examined for the ability to induce secretory and cellular responses in a pure population of bone marrow-derived mononuclear phagocytes. some of the highly purified ltas, in particular ltas from bacillus subtilis, s. pyogenes, e. faecalis, and enterococcus hirae, were able to affect each of the macropha ... | 1992 | 1500175 |
| differences in the formation of poles of enterococcus and bacillus. | the pole of enterococcus hirae (streptococcus faecium) is more pointed than that of bacillus subtilis; i.e. the pole of the former is prolate and the latter is oblate. both species form their poles by constructing annular additions on the inside surface. in both cases, the thick septum starts to split from the outside before the septum is complete. physiochemical considerations dictate that the peptidoglycan must be unstretched as laid down. however, it later becomes stressed and may stretch to ... | 1992 | 1573905 |
| extracellular and cellular distribution of muramidase-2 and muramidase-1 of enterococcus hirae atcc 9790. | a substantial portion of the second peptidoglycan hydrolase (muramidase-2) activity of enterococcus hirae atcc 9790 (formerly streptococcus faecium) is present in the supernatant culture medium. in contrast, nearly all muramidase-1 activity is associated with cells in the latent, proteinase-activatable form. muramidase-2 activity is produced and secreted throughout growth, with maximal levels attained at or near the end of exponential growth in a rich organic medium. muramidase-2 activity in the ... | 1992 | 1577692 |
| 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 ... | 1992 | 1637842 |
| 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 ... | 1991 | 1718341 |
| enterococcus hirae infection and focal necrosis of the brain of chicks. | | 1991 | 1746106 |
| enterococcus hirae in different animal species. | | 1991 | 1746125 |
| the enterococcus hirae r40 penicillin-binding protein 5 and the methicillin-resistant staphylococcus aureus penicillin-binding protein 2' are similar. | the penicillin-resistant enterococcus hirae r40 has a typical profile of membrane-bound penicillin-binding proteins (pbps) except that the 71 kda pbp5 of low penicillin affinity represents about 50% of all the pbps present. water-soluble tryptic-digest peptides were selectively produced from pbp5, their n-terminal regions were sequenced and synthetic oligonucleotides were used as primers to generate a 476 bp dna fragment by polymerase chain reaction. on the basis of these data, the pbp5-encoding ... | 1991 | 1747121 |
| detection of penicillin-binding proteins immunologically related to penicillin-binding protein 5 of enterococcus hirae atcc 9790 in enterococcus faecium and enterococcus faecalis. | penicillin-binding protein (pbp) 5 of enterococcus hirae atcc 9790 belongs to the class of the high-molecular mass, low-affinity pbps which have been correlated with penicillin resistance in most enterococcus species. polyclonal antibodies were raised against pbp 5 and used to detect immunologically related membrane proteins in e. faecium and e. faecalis strains. several strains of both species were found to have a membrane protein of similar molecular mass to e. hirae pbp 5 which reacted with t ... | 1991 | 1769542 |
| adaptation of streptococcus mutans and enterococcus hirae to acid stress in continuous culture. | streptococcus mutans gs-5 and ib1600 adapted to growth in acidic environments in continuous culture at slow (generation time = 8.3 h) or fast (generation time = 2.4 h) rates of growth in complex medium with a restricted glucose supply. the extent of adaptation was indicated by changes in minimum ph values attained by harvested cells suspended in dense suspensions with excess glucose and by increased levels of atpase activity assayed in permeabilized cells. also, adapted cells better withstood po ... | 1991 | 1829347 |
| primary structure of the alpha-subunit of vacuolar-type na(+)-atpase in enterococcus hirae. amplification of a 1000-bp fragment by polymerase chain reaction. | a 1000-bp fragment of enterococcus hirae genomic dna was amplified by the polymerase chain reaction method, using the oligonucleotide primers designed from amino acid sequences of both amino-terminal and a tryptic fragment of the na(+)-atpase alpha-subunit in this organism. dna sequencing of this product revealed that the amino acid sequence of na(+)-atpase alpha-subunit is highly homologous to the corresponding sequences of large (alpha) subunits of vacuolar (archaebacterial) type h(+)-atpases, ... | 1991 | 1835700 |
| separation of the poly(glycerophosphate) lipoteichoic acids of enterococcus faecalis kiel 27738, enterococcus hirae atcc 9790 and leuconostoc mesenteroides dsm 20343 into molecular species by affinity chromatography on concanavalin a. | this study shows for the first time microheterogeneity of 1,3-linked poly(glycerophosphate) lipoteichoic acids. the lipoteichoic acids investigated were those of enterococcus faecalis kiel 27738 (i), enterococcus hirae (streptococcus faecium) atcc 9790 (ii), and leuconostoc mesenteroides dms 20343 (iii). lipoteichoic acids ii and iii are partially substituted by mono-, di-, tri-, and tetra-alpha-d-glucopyranosyl residues with (1----2) interglycosidic linkages. lipoteichoic acid i is substituted ... | 1991 | 1901041 |
| composition of the enterococcal and streptococcal intestinal flora of poultry. | identification to species level showed that enterococcus faecalis and ent. faecium largely dominated the enterococcal and streptococcal gut flora of 1-d-old chicks. enterococcus faecalis was rare in 3- to 5-week-old broilers. two species, ent. faecium and streptococcus alactolyticus, were isolated from nearly all broilers examined. enterococcus hirae and ent. durans were found in the small intestines of this category of poultry. in layers and parent stock of over 12 weeks of age, ent. cecorum do ... | 1991 | 1910033 |
| mode of membrane insertion and sequence of a 32-amino acid peptide stretch of the penicillin-binding protein 4 of enterococcus hirae. | analysis of water-soluble derivatives of the enterococcus hirae 75-kda membrane-bound penicillin-binding protein 4 (pbp4) has yielded the amino acid sequence of a 32-amino acid polypeptide stretch. this peptide is similar to peptide segments known to occur in the n-terminal domain of high-mr pbps of class b. the e. hirae pbp4 probably belongs to the same class. it is anchored in the membrane at the n-terminus of the polypeptide chain. | 1991 | 1936941 |
| relationship between changes in buoyant density and formation of new sites of cell wall growth in cultures of streptococci (enterococcus hirae atcc 9790) undergoing a nutritional shift-up. | when the glutamate concentration of cultures of enterococcus hirae was raised from 20 to 300 micrograms/ml, the mass doubling time decreased from ca. 85 to 45 min in 9 min, but balanced growth was not reestablished for 30 to 40 min. during the unbalanced period of growth, rna and protein synthesis proceeded more rapidly than did peptidoglycan synthesis, buoyant density increased from ca. 1.1024 to 1.1075 g/ml, and the rate of formation of new cell wall growth sites transitorily accelerated above ... | 1990 | 1973928 |
| molecular analysis of lipoteichoic acid from streptococcus agalactiae. | a method for the analysis of lipoteichoic acid (lta) by polyacrylamide gel electrophoresis (page) is described. purified lta from streptococcus agalactiae tended to smear in the upper two-thirds of a 30 to 40% linear polyacrylamide gel, while the chemically deacylated form (cdlta) migrated as a ladder of discrete bands, reminiscent of lipopolysaccharides. the deacylated polymer appeared to separate in this system on the basis of size, as evident from results obtained from page analysis of cdlta ... | 1991 | 1987143 |
| effect of non-beta-lactam antibiotics on penicillin-binding protein synthesis of enterococcus hirae atcc 9790. | fosfomycin, bacitracin and vancomycin in combination with penicillin exhibit a synergic effect against enterococcus hirae atcc 9790. this strain, when incubated in presence of the mic of non-beta-lactam antibiotics, showed an alternated pattern of pbps. bacitracin and vancomycin caused a decrease in the density of all pbps while fosfomycin only reduced that of pbp 6. it is suggested that the observed synergy is a consequence of the inhibition of pbp synthesis by antibiotics which act on the earl ... | 1991 | 2037534 |
| species identities of enterococci isolated from clinical specimens. | conventional tests and commercially available systems were used to determine the species identities of clinical isolates of enterococci. strict adherence to the conventional test scheme of facklam and collins (r. r. facklam and m. d. collins, j. clin. microbiol. 27:731-734, 1989) resulted in the misidentification of lactose-negative enterococcus faecalis isolates as enterococcus solitarius, but this problem was overcome by the application of additional tests. the commercially available systems t ... | 1990 | 2108992 |
| evaluation of microscan for identification of enterococcus species. | emerging drug resistance of the enterococci necessitates differentiation from group d streptococci and accurate species identification. microscan (baxter healthcare corp., west sacramento, calif.) has recently developed a microdilution system for identification and antibiotic susceptibility testing of gram-positive cocci. to evaluate the ability of this system to identify enterococcus species, 100 isolate identified as enterococci by microscan were tested by conventional media and 60 isolates of ... | 1990 | 2116449 |
| efficient electrotransformation of enterococcus hirae with a new enterococcus-escherichia coli shuttle vector. | in the present study, an enterococcus-escherichia coli shuttle vector, pc3, was constructed that allows efficient transformation by electroporation of enterococcus hirae atcc9790. 5 x 10(6) transformants per microgram of plasmid dna were obtained, using a commercial capacitor discharge device with an improved circuitry and a home-made electrode assembly, delivering pulses of 24 kv/cm across the cell suspension. the transformants were stable without selective pressure and plasmid dna reisolated f ... | 1990 | 2116916 |
| heterogeneity among the flavin-containing nadh peroxidases of group d streptococci. analysis of the enzyme from streptococcus faecalis atcc 9790. | polyclonal antisera prepared against the purified nadh peroxidase from streptococcus faecalis atcc 9790 (enterococcus hirae) do not cross-react with the atcc 11700 enzyme. comparative tryptic maps of the two proteins indicate that the differences in primary structures extend beyond those localized to respective antigenic epitopes. alignments of the nh2-terminal and active-site cysteinyl peptide sequences of the two streptococcal peroxidases reveal identities of 50 and 67% in the respective overl ... | 1990 | 2161844 |
| electrogenic transport by the enterococcus hirae atpase. | a transport atpase from enterococcus hirae was reconstituted in lipid vesicles and its electrogenic action investigated with the fluorescent dye oxonol vi as membrane potential probe. reconstitution in bacterial and in soybean phospholipid mixtures led to transport-active vesicle preparations. inside-out oriented atpase molecules were activated by the addition of atp to the extravesicular medium, generating in all experiments an intravesicularly positive potential. the extravesicular ph strongly ... | 1990 | 2164846 |
| characterization of an enterococcus hirae penicillin-binding protein 3 with low penicillin affinity. | enterococcus hirae s185, a clinical isolate from swine intestine, exhibits a relatively high resistance to penicillin and contains two 77-kda penicillin-binding proteins 3 of high (pbp 3s) and low (pbp 3r) affinity to penicillin, respectively. a laboratory mutant s185r has been obtained which overproduces pbp 3r and has a highly increased resistance to penicillin. peptide fragments specifically produced by trypsin and sv8 protease digestions of pbp 3r were isolated, and the amino acid sequences ... | 1990 | 2254261 |
| properties of cell wall-associated dd-carboxypeptidase of enterococcus hirae (streptococcus faecium) atcc 9790 extracted with alkali. | dd-carboxypeptidase (dd-cpase) activity of enterococcus hirae (streptococcus faecium) atcc 9790 was extracted from intact bacteria and from the insoluble residue (crude cell wall fraction) of mechanically disrupted bacteria by a brief treatment at ph 10.0 (10 mm glycine-naoh) at 0 degrees c or by extraction with any of several detergents. extractions with high salt concentrations failed to remove dd-cpase activity from the crude wall fraction. in contrast to n-acetylmuramoylhydrolase (both muram ... | 1990 | 2361945 |
| the second peptidoglycan hydrolase of streptococcus faecium atcc 9790 covalently binds penicillin. | a second peptidoglycan hydrolase (muramidase-2) of streptococcus faecium atcc 9790 (enterococcus hirae) has been purified to apparent homogeneity. the enzyme has been shown to be a beta-1,4-n-acetylmuramoylhydrolase (muramidase; ec 3.2.1.17) and to differ in substrate specificity from a previously isolated muramidase. purified enzyme appears as two protein staining bands with molecular masses of 125 and 75 kilodaltons (kda) on polyacrylamide gels after sodium dodecyl sulfate electrophoresis. elu ... | 1989 | 2753858 |
| active-site and membrane topology of the dd-peptidase/penicillin-binding protein no. 6 of enterococcus hirae (streptococcus faecium) a.t.c.c. 9790. | the membrane-bound 43,000-mr penicillin-binding protein no. 6 (pbp6) of enterococcus hirae consists of a 30,000-mr dd-peptidase/penicillin-binding domain and a approximately 130-residue c-terminal appendage. removal of this appendage by trypsin proteolysis has no marked effect on the catalytic activity and penicillin-binding capacity of the pbp. anchorage of the pbp in the membrane appears to be mediated by a short 15-20-residue stretch at the c-terminal end of the appendage. the sequence of the ... | 1989 | 2803261 |
| enterococcus hirae implicated as a cause of diarrhea in suckling rats. | a lancefield group d enteric streptococcus was isolated from diarrheic suckling rats that had been inoculated orally with stool from a diarrheic human. after oral administration of the organism to other suckling rats, diarrhea was reproduced, and the enteric streptococcus was reisolated. the brush border of small intestinal villi in affected animals was coated with numerous adherent gram-positive cocci. the organism was identified as enterococcus hirae by a battery of biochemical tests. these an ... | 1988 | 3053777 |
| an iron-regulated gene, maga, encoding an iron transport protein of magnetospirillum sp. strain amb-1. | magnetospirillum sp. amb-1 is a freshwater magnetic bacterium which synthesizes intracellular particles of magnetite (fe3o4). a genomic dna fragment required for synthesis of magnetic particles was previously isolated from a nonmagnetic transposon tn5 mutant. we have determined the complete nucleotide sequence of this fragment. the 2975-base pair region contains two putative open reading frames. one open reading frame, designated maga, encodes a polypeptide which is homologous to the cation effl ... | 1995 | 7499342 |
| ribosomal rna gene (rrn) organization in enterococci. | a cloned 1.8-kb probe containing the 3' end of 16s ribosomal rna and the 5' end of 23s ribosomal rna from enterococcus hirae was used to analyze various endonuclease digests of enterococci. in the atcc strains tested we observed a remarkable conservation of the apai sites in the rrn operons, and a partial conservation of ecori sites. using a number of other endonuclease digestions with the apai rrn probe, we estimate the number of rrn operons in enterococci to be between five and six. | 1994 | 7521309 |
| identification of a gene (arpu) controlling muramidase-2 export in enterococcus hirae. | muramidase-2 of enterococcus hirae is a 74-kda peptidoglycan hydrolase that plays a role in cell wall growth and division. to study its regulation, we isolated a mutant defective in muramidase-2 release under certain growth conditions. this mutant had cell walls which apparently lacked 74-kda muramidase-2 but which accumulated two proteolytic fragments of 32 and 43 kda, which exhibited muramidase-2 activity in the membrane fraction. by complementation cloning, we identified a 2.6-kb fragment of ... | 1995 | 7592343 |
| purification and characterization of the catalytic moiety of vacuolar-type na(+)-atpase from enterococcus hirae. | we have previously reported the molecular cloning and sequences of the ntp genes for enterococcus hirae na(+)-translocating atpase [takase, k., kakinuma, s., yamato, i., konishi, k., igarashi, k., and kakinuma, y. (1994) j. biol. chem. 269, 11037-11044]; the expected structure of this enzyme complex resembles those of the vacuolar h(+)-atpase complexes in eukaryotes. in this paper we report purification and characterization of the catalytic moiety of na(+)-atpase, whose molecular size was about ... | 1994 | 7706221 |
| potassium/proton antiport system of growing enterococcus hirae at high ph. | the cytoplasmic ph (phin) of enterococcus hirae growing at ph 9.2 was maintained at about 8.1. membrane-permeating amines such as ammonia alkalinized the phin from 8.1 to 9.0 at a high concentration and induced k+ extrusion. the phin alkalinization was transient; the phin fell from 9.0 to the original value of ph 8.1, at which point k+ extrusion ceased, and remained constant. cells accumulated ammonium ion to an extent stoichiometrically equivalent to the k+ loss. this bacterium continued to gro ... | 1995 | 7721716 |
| copper and silver transport by copb-atpase in membrane vesicles of enterococcus hirae. | the p-type atpase, copb, of enterococcus hirae is required for the copper resistance displayed by this organism and thus was postulated to be a copper pump. using 64cu+ and 110mag+, we here show atp-driven copper and silver accumulation catalyzed by copb in native inside-out membrane vesicles of e. hirae. copb atpase exhibited an apparent km for cu+ and ag+ of 1 microm and for atp of 10 microm. transport was maximal at ph 6 and had an apparent vmax of 0.07 nmol.min-1.mg-1 for both copper and sil ... | 1995 | 7721839 |
| a putative p-type cu(2+)-transporting atpase gene on chromosome ii of saccharomyces cerevisiae. | we have sequenced a gene on the right arm near the telomere of chromosome ii of saccharomyces cerevisiae which codes for a putative p-type cation-transporting atpase (pca1). the gene codes for a 1216 amino acids protein. the pca1 gene expresses a 3.5 kb message in both haploid and diploid cells when grown in glucose-based rich medium ypd. the gene product is most similar at the c-terminal region to a human copper-transporting atpase and enterococcus hirae copper-transporting atpases and also an ... | 1994 | 7754711 |
| a survey of antimicrobial susceptibility of clinical isolates of enterococcus spp. from irish hospitals. | nosocomial enterococcal infections are increasing. in order to establish the species distribution and antibiotic resistance patterns of enterococci in clinical specimens from hospitalized patients, we undertook a survey of 23 irish hospitals. one thousand and five viable enterococcal strains were studied. nine different species of enterococci were identified, including enterococcus faecalis (84%); enterococcus faecium (9%); and enterococcus hirae (3%). the most common sites of isolation were the ... | 1995 | 7768768 |
| molecular and structural requirements of a lipoteichoic acid from enterococcus hirae atcc 9790 for cytokine-inducing, antitumor, and antigenic activities. | comparison was made between the immunobiological and antigenic properties of two lipoteichoic acid (lta) fractions (lta-1 and -2) from enterococcus hirae atcc 9790, their glycolipid portions, and synthetic compounds partially mimicking the above bacterial products. the more lipophilic lta-2 fraction was capable of inducing serum tumor necrosis factor alpha and interleukin-6 in muramyldipeptide-primed mice and serum gamma interferon in those primed with propionibacterium acnes. the lta-2 fraction ... | 1995 | 7806384 |
| overproduction of a low-affinity penicillin-binding protein and high-level ampicillin resistance in enterococcus faecium. | five ampicillin-resistant clinical isolates of enterococcus faecium were analyzed for a correlation between overproduction of the low-affinity penicillin-binding protein (pbp 5) and the level of ampicillin resistance. comparison was made with one susceptible clinical isolate and its ampicillin-resistant derivative obtained in the laboratory by selection with increasing concentrations of penicillin. overproduction of the low-affinity pbp relative to the susceptible isolate was noted in moderately ... | 1994 | 7811006 |
| newer systems for bacterial resistances to toxic heavy metals. | bacterial plasmids contain specific genes for resistances to toxic heavy metal ions including ag+, aso2-, aso4(3-), cd2+, co2+, cro4(2-), cu2+, hg2+, ni2+, pb2+, sb3+, and zn2+. recent progress with plasmid copper-resistance systems in escherichia coli and pseudomonas syringae show a system of four gene products, an inner membrane protein (pcod), an outer membrane protein (pcob), and two periplasmic cu(2+)-binding proteins (pcoa and pcoc). synthesis of this system is governed by two regulatory p ... | 1994 | 7843081 |
| electrogenic na+ transport by enterococcus hirae na(+)-atpase. | energy-dependent generation of a membrane potential (delta psi) (-45 mv, interior negative) was observed in the f0f1, h(+)-atpase-defective mutant of enterococcus hirae. the generation of delta psi was found at high ph (but not at low ph), for which intracellular na+ was required but not extracellular k+. the delta psi-generating activity was induced in cells cultured in media containing high concentrations of na+, and was not observed in the na(+)-atpase mutants. these results suggest that e. h ... | 1995 | 7867809 |
| two trans-acting metalloregulatory proteins controlling expression of the copper-atpases of enterococcus hirae. | enterococcus hirae possesses two p-type atpases, copa and copb, that are involved in copper homeostasis. these enzymes are induced by extracellular copper concentrations that are either too low or too high for optimal growth. to identify the regulatory proteins involved in induction, the dna upstream of copa was cloned and sequenced. following a putative promoter region, it contains two genes, copy and copz, that encode proteins of 145 and 69 amino acids, respectively. both proteins contain meta ... | 1995 | 7876197 |
| molecular cloning and nucleotide sequence of the gene encoding the major peptidoglycan hydrolase of lactococcus lactis, a muramidase needed for cell separation. | a gene of lactococcus lactis subsp. cremoris mg1363 encoding a peptidoglycan hydrolase was identified in a genomic library of the strain in puc19 by screening escherichia coli transformants for cell wall lysis activity on a medium containing autoclaved, lyophilized micrococcus lysodeikticus cells. in cell extracts of l. lactis mg1363 and several halo-producing e. coli transformants, lytic bands of similar sizes were identified by denaturing sodium dodecyl sulfate (sds)-polyacrylamide gels contai ... | 1995 | 7883712 |
| antibacterial activity of 7-aminocholesterol, a new sterol. | a new sterol, 7-aminocholesterol, which inhibits growth of saccharomyces cerevisiae, also displayed antibiotic activity against gram-positive bacteria. the 50% growth inhibitory concentration against strains of listeria innocua, l. monocytogenes, staphylococcus aureus, enterococcus hirae and bacillus cereus was 3 microm. | 1995 | 7896083 |
| involvement of folic acid and methionine in the synthesis of certain membrane-associated nucleotide sugars by enterococcus hirae. | a membrane preparation from enterococcus hirae contained udp and methyl-udp (mudp) monosaccharides. this preparation, when incubated with combinations of folic acid, l-serine, and s-adenosyl-l-methionine in a reaction system containing udp-glucose, promoted synthesis of certain mudp sugars. folic acid and serine produced mudp-glucose and mudp-rhamnose; s-adenosylmethionine produced mudp-glucose, mudp-mannose, and mudp-fucose. | 1994 | 7928976 |
| p-type atpase from the cyanobacterium synechococcus 7942 related to the human menkes and wilson disease gene products. | dna encoding a p-type atpase was cloned from the cyanobacterium synechococcus 7942. the cloned ctaa gene encodes a 790-amino acid polypeptide related to the copa cu(2+)-uptake atpase of enterococcus hirae, to other known p-type atpases, and to the candidate gene products for the human diseases of copper metabolism, menkes disease and wilson disease. disruption of the single chromosomal gene in synechococcus 7942 by insertion of an antibiotic-resistance cassette results in a mutant cell line with ... | 1994 | 7937823 |
| resistance of enterococcus faecium to neutrophil-mediated phagocytosis. | during a previous study of the opsonic requirements for neutrophil (polymorphonuclear leukocyte [pmn])-mediated killing of enterococci, we identified two strains of enterococcus faecium (tx0015 and tx0016) that were resistant to pmn-mediated killing. to better define the mechanism of this resistance, we examined phagocytosis with a fluorescence assay and found that tx0016 was completely resistant to phagocytosis by pmns; this finding was confirmed by electron microscopy. examination of multiple ... | 1994 | 7960141 |
| cloning, sequencing and expression in escherichia coli of the low-affinity penicillin binding protein of enterococcus faecalis. | low-affinity penicillin binding proteins are particular membrane proteins, in several gram-positive bacteria, which are involved in beta-lactam antibiotic resistance. the structural gene for the low-affinity penicillin binding protein 5 (pbp5) of enterococcus faecalis was cloned and sequenced. from the sequence of the 3378 bp, a 2040 bp coding region was identified. from biochemical analysis it emerges that e. faecalis pbp5 is a type ii membrane protein with an uncleaved n-terminal and is compos ... | 1994 | 7988905 |
| differential susceptibilities of enterococcal species to elfamycin antibiotics. | the elfamycins are a class of naturally occurring antibiotics not currently used in the therapy of human disease. enterococcus faecium and closely related species (enterococcus durans and enterococcus hirae) are susceptible to these antibiotics, while isolates of enterococcus faecalis and other enterococcal species are highly resistant. among enterococci, susceptibility or resistance to elfamycins appears to be determined by the bacterial protein synthesis elongation factor ef-tu. elfamycin susc ... | 1994 | 7989561 |
| induction of the putative copper atpases, copa and copb, of enterococcus hirae by ag+ and cu2+, and ag+ extrusion by copb. | the two p-type atpases copa and copb are effecting regulation of cellular copper activity in enterococcus hirae. with antibodies against these atpases, we showed on western blots the simultaneous induction of copa and copb by copper or silver ions. copper contents of wild type and mutant cells lacking either copa, copb or both enzymes were measured by atomic absorption. strains disrupted in copb showed clearly enhanced copper contents. mutants lacking copb also lost the ability of energy depende ... | 1994 | 8037745 |
| primary structure of two p-type atpases involved in copper homeostasis in enterococcus hirae. | we cloned an operon, copab, from enterococcus hirae encoding two p-type atpases of 727 and 745 amino acids, respectively. both enzymes display heavy metal ion binding motifs in their polar n-terminal region. with an antibody against copb, we showed on western blots that expression of the operon is induced by either low or high ambient copper concentrations. disruption of the copa gene renders the cells dependent, whereas copper disruption of copb results in a copper-sensitive phenotype. copa exh ... | 1993 | 8048974 |
| characteristics of an ethidium efflux system in enterococcus hirae. | an energy-dependent efflux system for ethidium and related cations has been detected in enterococcus hirae atcc 9790. the system was partially expressed when the organism was grown on a complex medium but was induced by the addition of phosphonium ions and related compounds. mutants showing constitutive expression of the efflux system have been isolated on the basis of increased resistance to ethidium. | 1994 | 8056283 |
| pathogenicity of enterococcus hirae for chicken embryos and betamethasone-treated chicks. | an isolate enterococcus hirae was used to determine its pathogenicity for chicken embryos and for chicks treated with betamethasone. e hirae was inoculated intravenously into four-day-old chicks which had been treated for three consecutive days with betamethasone, and chick embryos were inoculated into the allantoic cavity with 10(2) and 10(3) bacteria. e hirae was not pathogenic for the chicks or for the embryos. | 1994 | 8073195 |
| the type i macrophage scavenger receptor binds to gram-positive bacteria and recognizes lipoteichoic acid. | macrophage scavenger receptors exhibit unusually broad binding specificity for polyanionic ligands and have been implicated in atherosclerosis and various host defense functions. using a radiolabeled, secreted form of the type i bovine macrophage scavenger receptor in an in vitro binding assay, we have found that this receptor binds to intact gram-positive bacteria, including streptococcus pyogenes, streptococcus agalactiae, staphylococcus aureus, enterococcus hirae, and listeria monocytogenes. ... | 1994 | 8127896 |
| operon of vacuolar-type na(+)-atpase of enterococcus hirae. | the gram-positive bacteria enterococcus hirae expel sodium by two systems: a na+/h(+)-antiporter and a vacuolar-type na(+)-atpase. we isolated a mutant, nalka, defective in the na(+)-atpase. nalka grew normally at neutral ph but was unable to grow in the presence of > 100 mm sodium at ph 9.5. by functional complementation at high ph, we cloned pes1, a plasmid from an e. hirae gene bank containing a 5.2-kilobase pair region of genomic dna. the genomic dna in pes1 contains five complete open readi ... | 1994 | 8144530 |
| [study of combinations of antimicrobial agents. development of the method]. | we developed and validated a micromethod similar to the checkerboard method in antibiotherapy to study the efficiency of antiseptic and disinfectant molecules. the determination of the fbc index (fractional bactericidal concentration) on 4 reference strains (escherichia coli, pseudomonas aeruginosa, staphylococcus aureus, enterococcus hirae) for 4 associations (2-benzyl-4 chlorophenol--iodophor; cetrimide-iodophor, 2 benzyl-4 chlorophenol--formaldehyde; hexamidine--formaldehyde) revealed 2 syner ... | 1993 | 8154787 |
| sequencing and characterization of the ntp gene cluster for vacuolar-type na(+)-translocating atpase of enterococcus hirae. | we have previously reported the dna and amino acid sequences for the three genes (ntpa, ntpb, and ntpk) encoding the a, b, and k (proteolipid) subunits, respectively, of na(+)-translocating atpase of a eubacterium enterococcus hirae (kakinuma, y., kakinuma, s., takase, k., konishi, k., igarashi, k., and yamato, i. (1993) biochem. biophys. res. commun. 195, 1063-1069). in this paper we report the entire nucleotide sequence of the ntp gene cluster coding for this multisubunit enzyme. the cluster c ... | 1994 | 8157629 |
| copper pumping atpases: common concepts in bacteria and man. | recently, four genes encoding putative copper pumping atpases have been cloned from widely different sources: two genes from enterococcus hirae that are involved in copper metabolism and two human genes that are defective in the copper-related wilson and menkes disease. the predicted gene products are p-type atpases. they exhibit extensive sequence similarity and appear to be members of a new class of atp driven copper pumps involved in the regulation of cellular copper. | 1994 | 8206157 |
| na+ and k+ transport by 4-chlorophenylurethane-monensin in enterococcus hirae de-energized and energized cells studied by 23na-nmr and k+ atomic absorption. | na+ and k+ movements induced by 4-chlorophenylurethane-monensin, which presents an inverted ion selectivity (k+ > na+) in model systems compared with monensin, were followed on enterococcus hirae cells by 23na-nmr and k+ atomic absorption. for de-energized cells, the urethane derivative is much more selective for k+ than monensin, but only at low concentrations (10(-3)-10(-4) mm). for higher concentrations, as previously shown for monensin, the sodium and potassium movements are driven by the io ... | 1993 | 8218359 |
| [experimental study of the antibacterial activity of cloth impregnated with a disinfectant solution]. | disinfecting cloths were commercialized for several years. the solutions of disinfectant used are generally active in vitro in the conditions required by the french standards published by afnor, but it is also necessary to know the effectiveness of disinfecting cloths in conditions of use. we describe in this paper a method for this determination. four bacterial stains recommended in the french standards were used: staphylococcus aureus atcc 9144, enterococcus hirae atcc 10541, pseudomonas aerug ... | 1993 | 8233637 |
| experimental infection of chicks with enterococcus hirae. | | 1993 | 8236693 |
| functional expression of the enterococcus hirae nah-antiporter in escherichia coli. | we recently described the cloning of napa, the putative structural gene for the nah-antiporter of enterococcus hirae (waser, m., bienz-hess, d., davies, k., and solioz, m. (1992) j. biol. chem. 267, 5396-5400). to analyze the gene product of napa, we expressed it in escherichia coli. when placed under the control of a t7 promoter, napa could be transcribed and labeled specifically with [35s]methionine. the resultant gene product exhibited an apparent m(r) of 3,4 x 10(4) when subjected to sodium ... | 1993 | 8253756 |
| presumptive fecal streptococci in environmental samples characterized by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis. | the use of fecal streptococci as fecal indicators requires better knowledge of the ecology of these bacteria. we isolated 371 presumptive fecal streptococci from environmental samples--domestic wastewater, forest industry wastewater, contaminated surface and seawater, well water, cow dung, bird droppings, and pristine waters--and clustered them according to their protein profiles in one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. some clusters could be tentati ... | 1993 | 8357252 |
| a gene encoding the 16-kda proteolipid subunit of enterococcus hirae na(+)-atpase complex. | by further sequencing the cloned genome dna of enterococcus hirae that retains the genes encoding two major subunits of na(+)-transport atpase (takase, k., yamato, i., and kakinuma, y. (1993) j. biol. chem. 268, 11610-11616), we found a gene, ntpk, encoding a very hydrophobic protein of 156 amino acids (mr = 16,036). the amino acid sequence deduced from the ntpk gene matched with the partial sequence of a 16-kda protein purified as the proteolipid component of na(+)-atpase. the amino acid sequen ... | 1993 | 8373385 |
| complementation of an enterococcus hirae (streptococcus faecalis) mutant in the alpha subunit of the h(+)-atpase by cloned genes from the same and different species. | we isolated an enterococcus hirae (formerly streptococcus faecalis) mutant, designated ms117, in which 'g' at position 301 of the alpha-subunit gene of the f1f0 type of h(+)-atpase was deleted. ms117 had low h(+)-atpase activity, was deficient in the regulatory system of cytoplasmic ph, and was unable to grow at ph 6.0. when the alpha-subunit gene of e. hirae h(+)-atpase was ligated with the shuttle vector phy300plk at the downstream region of the tet gene of the vector, it was expressed without ... | 1993 | 8412656 |
| molecular analysis of lipid macroamphiphiles by hydrophobic interaction chromatography, exemplified with lipoteichoic acids. | analyzed were (i) the oligoglucosyl-, alanyl-substituted poly(glycerophosphate) lipoteichoic acid of enterococcus hirae containing glc(alpha 1-2)glc(alpha 1-3)acyl2-gro and a phosphatidyl derivative thereof as lipid anchor, (ii) the poly(digalactosyl, galactosylglycerophosphate) lipoteichoic acid of lactococcus garvieae containing the same glycolipid and an acyl derivative of it, and (iii) the n-acetylglucosaminyl-, alanyl-substituted poly(glycerophosphate)lipoteichoic acid of staphylococcus aur ... | 1993 | 8434795 |
| identification of a genetic element (psr) which negatively controls expression of enterococcus hirae penicillin-binding protein 5. | enterococcus hirae atcc 9790 produces a penicillin-binding protein (pbp5) of low penicillin affinity which under certain conditions can take over the functions of all the other pbps. the 7.1-kb ecori fragment containing the pbp5 gene of this strain and of two mutants, of which one (e. hirae r40) overproduces pbp5 and the other (e. hirae rev14) does not produce pbp5, was cloned in puc18 and sequenced. in the 7.1-kb ecori fragment cloned from strain atcc 9790, an open reading frame (psr) potential ... | 1993 | 8458847 |
| cloning and sequencing of the low-affinity penicillin-binding protein 3r-encoding gene of enterococcus hirae s185: modular design and structural organization of the protein. | the clinical isolate enterococcus hirae s185 has a peculiar mode of resistance to penicillin in that it possesses two low-affinity penicillin-binding proteins (pbps): the 71-kda pbp5, also found in other enterococci, and the 77-kda pbp3r. the two pbps have the same low affinity for the drug and are immunochemically related to each other. the pbp3r-encoding gene has been cloned and sequenced, and the derived amino acid sequence has been compared by computer-assisted hydrophobic cluster analysis w ... | 1993 | 8491705 |
| characterization of intergenic spacers in two rrn operons of enterococcus hirae atcc 9790. | two dna restriction enzyme fragments coding for the 3' termini of 16s rrna, the 5' termini of 23s rrna, and the intergenic spaces between them in enterococcus hirae atcc 9790 were cloned and sequenced. the intergenic space of one of these genes contains a trna(ala) sequence, whereas the other does not. nevertheless, the intergenic spaces contain several regions that exhibit high levels of sequence homology and are capable of forming structures with similar base pairs. an analysis of southern blo ... | 1993 | 8491737 |
| characterization of the sporulation-related gamma-d-glutamyl-(l)meso-diaminopimelic-acid-hydrolysing peptidase i of bacillus sphaericus nctc 9602 as a member of the metallo(zinc) carboxypeptidase a family. modular design of the protein. | the sporulation-related gamma-d-glutamyl-(l)meso-diaminopimelic-acid-hydrolysing peptidase i of bacillus sphaericus nctc 9602 has been analysed by proton-induced x-ray emission. it contains 1 equivalent zn2+ per mol of protein. as derived from gene cloning and sequencing, the b. sphaericus zn peptidase i is a two-module protein. a 100-amino-acid-residue n-terminal domain consisting of two tandem segments of similar sequences, is fused to a 296-amino-acid-residue c-terminal catalytic domain. the ... | 1993 | 8503890 |
| cloning and sequencing of the genes coding for the a and b subunits of vacuolar-type na(+)-atpase from enterococcus hirae. coexistence of vacuolar- and f0f1-type atpases in one bacterial cell. | the eubacterium enterococcus hirae atcc 9790 possesses a h(+)-translocating atpase, and the deduced amino acid sequences of the genes coding for this enzyme have indicated that it is a typical f0f1-type atpase (shibata, c., ehara, t., tomura, k., igarashi, k., and kobayashi, h. (1992) j. bacteriol. 174, 6117-6124). we cloned the ntpa and ntpb genes coding for the a and b subunits, respectively, of na(+)-translocating atpase from the same bacterium, and the full amino acid sequences of the two su ... | 1993 | 8505293 |
| identification of daptomycin-binding proteins in the membrane of enterococcus hirae. | daptomycin, a lipopeptide antibiotic active against gram-positive bacteria, was preliminarily shown to inhibit lipoteichoic acid (lta) synthesis as a consequence of membrane binding in the presence of ca2+ (p. canepari, m. boaretti, m. m. lleó, and g. satta, antimicrob. agents chemother. 34:1220-1226, 1990). in the present study, it is shown that, along with binding bacterial-membrane components, daptomycin binds the protein fraction with a noncovalent bond, as suggested by the instability of th ... | 1995 | 8540717 |
| cytokine-inducing glycolipids in the lipoteichoic acid fraction from enterococcus hirae atcc 9790. | five high molecular weight glycolipids capable of stimulating human peripheral whole-blood cell cultures to cause interleukin 6 (il-6) and tumor necrosis factor (tnf)-alpha induction were isolated from one of the lipoteichoic acid fractions (lta-2) extracted from enterococcus hirae atcc 9790 (tsutsui et al., (1991) fems microbiol. immunol. 76, 211-218) by a combination of hydrophobic interaction and anion-exchange chromatographies. this purification procedure resulted in a remarkable increase in ... | 1995 | 8589669 |
| importance of the e-46-d-160 polypeptide segment of the non-penicillin-binding module for the folding of the low-affinity, multimodular class b penicillin-binding protein 5 of enterococus hirae. | compared with the other class b multimodular penicillin- binding proteins (pbps), the low-affinity pbp5 responsible for penicillin resistance in enterococcus hirae r40, has an extended non-penicillin-binding module because of the presence of an approximately 110-amino-acid e-46(-)d-160 insert downstream from the membrane anchor. expression of pbp5 genes lacking various parts of the insert-encoding region gives rise to proteins that are inert in terms of penicillin binding, showing that during fo ... | 1996 | 8626310 |
| the ntpj gene in the enterococcus hirae ntp operon encodes a component of ktrii potassium transport system functionally independent of vacuolar na+-atpase. | the ntpj gene, the tail end in the vacuolar type na+-atpase (ntp) operon of enterococcus hirae, encodes a putative 49-kda hydrophobic protein resembling k+ transporter protein in saccharomyces cerevisiae (takase, k., kakinuma, s., yamato, i., konishi, k., igarashi, k., and kakinuma, y. (1994) j. biol. chem. 269, 11037-11044). northern blotting experiment revealed that the ntpj gene was transcribed as a cistron in the ntp operon. we constructed an enterococcus strain in which the ntpj gene was di ... | 1996 | 8626559 |
| the bradyrhizobium japonicum fixghis genes are required for the formation of the high-affinity cbb3-type cytochrome oxidase. | we report structural and functional analyses of the bradyrhizobium japonicum fixghis genes, which map immediately downstream of the fixnoqp operon for the symbiotically essential cbb3-type heme-copper oxidase complex. expression of fixghis, like that of fixnoqp, is strongly induced in cells grown microaerobically or anaerobically. a fixghi deletion led to the same prominent phenotypes as those known from a fixnoqp deletion: defective symbiotic nitrogen fixation (fix-) and decreased cytochrome ox ... | 1996 | 8661920 |
| the drosophila melanogaster gene vha14 encoding a 14-kda f-subunit of the vacuolar atpase. | a drosophila melanogaster (dm) cdna (vha14) encoding the 14-kda f-subunit of the vacuolar h(+)-atpase (v-atpase) has been cloned via homology with the corresponding manduca sexta (ms) gene. its deduced translation product is a 124-amino-acid polypeptide sharing 90% identity with the ms polypeptide and 50% identity with an analogous polypeptide of saccharomyces cerevisiae, and a more distant similarity to a subunit of the na(+)-transporting atpase of enterococcus hirae. homology was also found wi ... | 1996 | 8682310 |
| endocarditis in broiler breeder rearers due to enterococcus hirae. | | 1996 | 8686149 |
| plasmid-borne high-level resistance to gentamicin in enterococcus hirae, enterococcus avium, and enterococcus raffinosus. | enterococcus hirae, e. avium, and e. raffinosus isolated in romania, tunisia, and portugal harbored plasmids picc8, pip1700, and pip1701, respectively, encoding resistance to high levels of gentamicin (gmr). the gmr marker was carried on pip1700 by a tn4001-like element and on picc8 and pip1701 by tn4001-truncated structures. picc8 carried, in addition to gmr, chloramphenicol, erythromycin, and tetracycline-minocycline (tetm) resistance determinants. the gene tetm of picc8 was carried on a tn916 ... | 1996 | 8723479 |
| evidence that the pbp 5 synthesis repressor (psr) of enterococcus hirae is also involved in the regulation of cell wall composition and other cell wall-related properties. | psr has been reported by m. ligozzi, f. pittaluga, and r. fontana, (j. bacteriol. 175:2046-2051, 1993) to be a genetic element located just upstream of the structural gene for the low-affinity penicillin-binding protein 5 (pbp 5) in the chromosome of enterococcus hirae atcc 9790 and to be involved in the repression of pbp 5 synthesis. by comparing properties of strains of e. hirae that contain a full-length, functional psr with those of strains that possess a truncated form of the gene, we have ... | 1996 | 8752348 |
| influence of lipoteichoic acid structure on recognition by the macrophage scavenger receptor. | lipoteichoic acids (ltas) belong to the immunostimulatory class of molecules of gram-positive bacteria (gpb). previous investigations showed that the macrophage scavenger receptor (sr), a glycosylated trimeric transmembrane protein, binds directly to many gpb, possibly via lta. sr binding to other ligands is dependent upon the spatial characteristics of the repeating negative charge of the ligand. we therefore investigated sr recognition of lta species with various charge densities and distribut ... | 1996 | 8757870 |
| structure of the low-affinity penicillin-binding protein 5 pbp5fm in wild-type and highly penicillin-resistant strains of enterococcus faecium. | among its penicillin-binding proteins (pbps), enterococcus faecium possesses a low-affinity pbp5, pbp5fm, which is the main target involved in beta-lactam resistance. a 7.7-kb ecori chromosomal fragment of e. faecium d63r containing the pbp5fm gene was cloned and sequenced. two open reading frames (orfs) were found. a 2,037-bp orf encoded the deduced 73.8-kda pbp5fm, the amino acid sequences of which were, respectively, 99.8, 78.5, and 62% homologous to those of the low-affinity plasmid-encoded ... | 1996 | 8759860 |
| intracellular na+ regulates transcription of the ntp operon encoding a vacuolar-type na+-translocating atpase in enterococcus hirae. | the gram-positive bacterium enterococcus hirae has a vacuolar-type na+-translocating atpase that is encoded by the ntp operon (ntpfikecgabdhj) (takase, k., kakinuma, s., yamato, i., konishi, k., igarashi, k., and kakinuma, y. (1994) j. biol. chem. 269, 11037-11044). primer extension experiments identified the start site of transcription of this operon upstream of the ntpf gene. in parallel with the increases of both na+-pumping activity in whole cells and na+-stimulated atpase activity in the me ... | 1996 | 8798587 |
| modification of penicillin-binding protein 5 associated with high-level ampicillin resistance in enterococcus faecium. | high-level ampicillin resistance in enterococcus faecium has been shown to be associated with the synthesis of a modified penicillin-binding protein 5 (pbp 5) which had apparently lost its penicillin-binding capability (r. fontana, m. aldegheri, m. ligozzi, h. lopez, a. sucari, and g. satta. antimicrob. agents chemother. 38:1980-1983, 1994). the pbp5 gene of the highly resistant strain e. faecium 9439 was cloned and sequenced. the deduced amino acid sequence showed 77 and 54% homologies with the ... | 1996 | 8834879 |
| characterization of is1272, an insertion sequence-like element from staphylococcus haemolyticus. | we have previously shown (g. l. archer, d. m. niemeyer, j. a. thanassi, and m. j. pucci, antimicrob. agents chemother. 38:447-454, 1994) that some methicillin-resistant staphylococcal isolates contain a partial deletion of the genes (mecr1 and meci) that regulate the transcription of the methicillin resistance structural gene (meca). when a fragment of dna inserted at the point of the mecr1 deletion was used as a probe, hybridization with multiple bands was detected for staphylococcus haemolytic ... | 1996 | 8849253 |
| cloning and sequencing of the spore germination gene of bacillus megaterium atcc 12872: similarities to the nah-antiporter gene of enterococcus hirae. | the germination mutant tm-31 of bacillus megaterium atcc 12872, was isolated by transposon tn917 insertional mutagenesis. glucose, l-proline, l-leucine and kno3 germinated tm-31 poorly. the dna in the region of the tn917 insertion was cloned, and its nucleotide sequence determined. one major open reading frame was present on the cloned dna. the hydrophobic protein encoded is presumably membrane-associated. a homology search revealed that the gene encoded in the region of the tn917 insertion is h ... | 1996 | 8867604 |
| bacterial heavy metal resistance: new surprises. | bacterial plasmids encode resistance systems for toxic metal ions including ag+, aso2-, aso4(3-), cd2+, co2+, cro4(2-), cu2+, hg2+, ni2+, pb2+, sb3+, teo3(2-), tl+, and zn2+. in addition to understanding of the molecular genetics and environmental roles of these resistances, studies during the last few years have provided surprises and new biochemical mechanisms. chromosomal determinants of toxic metal resistances are known, and the distinction between plasmid resistances and those from chromoso ... | 1996 | 8905098 |
| definition of the single integration site of the pathogenicity locus in clostridium difficile. | we determined the nucleotide sequence 3.8 kb upstream and 5.2 kb downstream of the toxin genes a and b of clostridium difficile. nine orfs were discovered. based on pcr-directed approaches, two were attributed to the pathogenicity locus (paloc). the other seven were found in every c. difficile isolate obtained from the human gastrointestinal tract, respectless of their toxinogenicity. the orfs cdu1 and cdu2/2' upstream of the paloc displayed similarity to repressors of gram-positive bacteria (cd ... | 1996 | 8973304 |
| phosphoenzyme formation by purified, reconstituted copper atpase of enterococcus hirae. | the enterococcus hirae copb atpase serves in the secretion of excess copper from cells and belongs to the recently discovered, new class of heavy metal transport atpases. we here report the affinity purification of copb to near homogeneity and its reconstitution into phospholipid vesicles. in these proteoliposomes, the atpase formed an acylphosphate reaction intermediate with the gamma-phosphate of atp. atpase activity and phosphoenzyme formation were inhibited by vanadate with an i(50) of 0.1 m ... | 1996 | 8980139 |
| an na+-pumping v1v0-atpase complex in the thermophilic bacterium clostridium fervidus. | energy transduction in the anaerobic, thermophilic bacterium clostridium fervidus relies exclusively on na+ as the coupling ion. the na+ ion gradient across the membrane is generated by a membrane-bound atpase (g. speelmans, b. poolman, t. abee, and w. n. konings, j. bacteriol. 176:5160-5162, 1994). the na+-atpase complex was purified to homogeneity. it migrates as a single band in native polyacrylamide gel electrophoresis and catalyzes na+-stimulated atpase activity. denaturing gel electrophore ... | 1997 | 9023212 |
| copy is a copper-inducible repressor of the enterococcus hirae copper atpases. | the cop operon of enterococcus hirae effects copper homeostasis in this organism. it encodes a repressor, copy, an activator, copz, and two p-type copper atpases, copa and copb. expression of all four genes is regulated by the ambient copper. in this regulation, copy apparently acts as a copper-inducible repressor. by dnase i footprinting, it was shown that purified copy protected two discrete sites in the region encompassing nucleotides -71 to -11 relative to the translational start site and co ... | 1997 | 9083014 |