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plasmid copy number control: isolation and characterization of high-copy-number mutants of plasmid pe194.a plasmid, pe194, obtained from staphylococcus aureus confers resistance to macrolide, lincosamide, and streptogramin type b ("mls") antibiotics. for full expression, the resistance phenotype requires a period of induction by subinhibitory concentrations of erythromycin. a copy number in the range of 10 to 25 copies per cell is maintained during cultivation at 32 degrees c. it is possible to transfer pe194 to bacillus subtilis by transformation. in b. subtilis, the plasmid is maintained at a cop ...1979104975
homology of mycoplasma plasmid padb201 and staphylococcal plasmid pe194.the complete nucleotide sequence of padb201, a 1.7-kilobase cryptic plasmid from mycoplasma mycoides subsp. mycoides, is reported. the sequence contains a single large open reading frame capable of coding for a polypeptide of up to 198 codons long. the sequence of the putative polypeptide shows significant similarity to that of the repf gene product of staphylococcal plasmid pe194.19892644210
curing of plasmid pe194 with novobiocin and coumermycin a1 in bacillus subtilis and staphylococcus aureus.plasmid pe194 determining macrolide-lincosamid-streptogramin b resistance could be eliminated with novobiocin and coumermycin a1 in bacillus subtilis and staphylococcus aureus. in both organisms the curing effect depended on the temperature. in the case of staphylococcus aureus it increased very much at high temperatures, while in the case of bacillus subtilis only a moderate increase could be observed. the curing activity of coumermycin was substantially weaker than that of novobiocin in both b ...19872823505
[replication in yeasts of plasmid pe194 from staphylococcus aureus].the ability of the plasmid pe194 from s. aureus to serve as an autonomously replicating sequence (ars) in yeast was shown. the hybrid plasmid pld744 that contains pe194 and the yeast leu2 gene sequences is unstable in yeast like other yrp-vectors: the mitotic stability of the pld744 was as much as 1%. the plasmid pld712 that differs from pld744 by the existence of a centromeric sequence from the chromosome iii of yeast saccharomyces cerevisiae reveals about one order greater stability. the obser ...19863005842
characteristics of a soil-isolated bacillus subtilis phage, gs1, and gs1-mediated plasmid transduction.a previously described soil-isolated bacillus subtilis bacteriophage, gs1, was further characterized. it is a tailed phage with regular head morphology and a discrete base plate. gs1 belongs to morphological group a1 of bacillus phages. its tail measured 170 nm and the head width was 92 nm. gs1 produced turbid plaques on its natural host strain, but clear plaque variants occurred at high frequency. all attempts to transduce either erythromycin (em) or tetracycline (tc) resistance markers, presen ...19873111124
sequence and properties of pim13, a macrolide-lincosamide-streptogramin b resistance plasmid from bacillus subtilis.we initiated a study of pim13, a multicopy, macrolide-lincosamide-streptogramin b (mls) plasmid first isolated from a strain of bacillus subtilis and described by mahler and halvorson (j. gen. microbiol. 120:259-263, 1980). the copy number of this plasmid was about 200 in b. subtilis and 30 in staphylococcus aureus. the mls resistance determinant of pim13 was shown to be highly homologous to ermc, an inducible element on the s. aureus plasmid pe194. the product of the pim13 determinant was simil ...19863087948
[integration of various plasmids into the bacillus subtilis chromosome].some features of integration of temperature-sensitive pe194, pgg10 and pgg20 plasmids into the bacillus subtilis chromosome were studied. several auxotrophic mutations were obtained using insertion of these plasmids into the chromosome. the sites of plasmids for illegitimate recombination were determined. it was shown that the integration into the bac. subtilis chromosome is characteristic not only for the plasmid pe194 but is the property of staphylococcus aureus plasmid pc194 and escherichia c ...19852998925
construction and application of a promoter-probe plasmid that allows chromogenic identification in streptomyces lividans.we cloned a streptomyces coelicolor a3(2) dna fragment which directed synthesis of a brown pigment, presumably a shunt product in the actinorhodin biosynthetic pathway, on the plasmid vector pij41 in streptomyces lividans. the pigment production was observed only when the dna fragment was inserted downstream from a functional promoter sequence. by subcloning the fragment together with in vitro manipulation, a promoter-probe plasmid vector (parc1) with a unique bamhi cloning site was constructed ...19852984181
tn916-dependent conjugal transfer of pc194 and pub110 from bacillus subtilis into bacillus thuringiensis subsp. israelensis.the staphylococcus aureus plasmids pc194 and pub110 were introduced into bacillus thuringiensis subsp. israelensis by using the streptococcus faecalis transposon tn916 as a mobilizing agent. plasmid transfer occurred only when b. thuringiensis subsp. israelensis was mated with a b. subtilis donor that contained both pc194 and pub110 and tn916; plasmid transfer was not observed in the absence of the transposon. b. thuringiensis transconjugants resistant to chloramphenicol (cmr) and tetracycline ( ...19882853391
replication properties of pim13, a naturally occurring plasmid found in bacillus subtilis, and of its close relative pe5, a plasmid native to staphylococcus aureus.a naturally occurring plasmid from bacillus subtilis, pim13, codes for constitutively expressed macrolide-lincosamide-streptogramin b (mls) resistance, is stably maintained at a high copy number, and exists as a series of covalent multimers. the complete sequence of pim13 has been reported (m. monod, c. denoya, and d. dubnau, j. bacteriol. 167:138-147, 1986) and two long open reading frames have been identified, one of which (ermc') is greater than 90% homologous to the ermc mls resistance deter ...19872822666
characterization of a plasmid-specified ribosome methylase associated with macrolide resistance.the ermc gene of plasmid pe194 specifies resistance to the macrolidelincosamide-streptogramin b antibiotics. this resistance, as well as synthesis of the 29,000 dalton protein product of ermc, has been shown to be induced by erythromycin. weisblum and his colleagues have established that macrolide resistance is associated with a specific dimethylation of adenine in 23 s rrna. we show that pe194 specifies an rna methylase that can utilize either 50 s ribosomes or 23 s rrna as substrates. synthesi ...19816792593
expression in escherichia coli of a staphylococcal gene for resistance to macrolide, lincosamide, and streptogramin type b antibiotics.plasmid pbd9, which comprises two plasmids from staphylococcus aureus, pe194 and pub110, was joined to plasmid pbr322 by in vitro recombination to form plasmid pkh80. the ermc gene of plasmid pe194 confers inducible resistance to macrolide, lincosamide, and streptogramin type b antibiotics. when pkh80 was transferred to escherichia coli k-12, the bacteria became resistant to several of these antibodies.19826811564
insertion and amplification of foreign genes in the lactococcus lactis subsp. lactis chromosome.the plasmid pe194 is unable to replicate in lactococcus lactis subsp. lactis (formerly streptococcus lactis). when linked to resident bacteriophage sequences, pe194 was able to integrate into the l. lactis subsp. lactis chromosome either by campbell-like recombination or by double crossing over with deletion. integration occurred into the dna of the prophage and prevented its multiplication. when a selective pressure was applied to an integrant in which pe194 was flanked by two direct repeats of ...19892504115
temperature sensitivity of plasmid pe194 in the recombination deficient staphylococcus aureus strain rn981. 19817185347
localization of the replication origin of plasmid pe194.the pe194 replication origin was localized to a 265-base-pair interval by analyzing the ability of purified pe194 restriction fragments to direct replication of heterologous plasmids. replication was dependent upon repf protein supplied in trans. the origin region contained a gc-rich dyad symmetry which may serve as the repf target.19892496117
identification of plasmid and bacillus subtilis chromosomal recombination sites used for pe194 integration.the plasmid pe194 (3.7 kilobases) is capable of integrating into the genome of the bacterial host bacillus subtilis in the absence of the major homology-dependent rece recombination system. multiple recombination sites have been identified on both the b. subtilis chromosome and pe194 (j. hofemeister, m. israeli-reches, and d. dubnau, mol. gen. genet. 189:58-68, 1983). the b. subtilis chromosomal recombination sites were recovered by genetic cloning, and these sites were studied by nucleotide seq ...19892496116
conformational alterations in the ermc transcript in vivo during induction.ermc is an inducible antibiotic resistance gene from staphylococcus aureus, one of several whose expression is regulated at the level of mrna secondary structure. during induction of ermc, the inhibition of a ribosome active in translation of a short leader peptide by low levels of antibiotic belonging to the macrolide-lincosamide-streptogramin b family is believed to cause a rearrangement in mrna secondary structure. the resultant conformational isomerization unmasks the methylase ribosome bind ...19892480236
replication control genes of plasmid pe194.pe194, a 3.7-kilobase plasmid, confers resistance to macrolide, lincosamide, and streptogramin b antibiotics. the previously identified cop and repf genes of pe194 have been further localized by molecular cloning and mutational analysis together with dna sequencing. the cfoib fragment of pe194 is capable of autonomous replication and contains both genes. most of this region has been resequenced, and two errors reported in a previous study have been corrected. the corrected sequence indicates tha ...19872443486
messenger rna from staphylococcus aureus that specifies macrolide-lincosamide-streptogramin resistance. demonstration of its conformations and of the leader peptide it encodes.the +1 site for transcription initiation of the inducible 23 s rrna adenine methylase encoded by plasmid pe194 was determined experimentally by nuclease s1 mapping of mrna synthesized in vivo, and by nuclease t1 mapping of (5'-gamma-32p)-end-labeled transcripts synthesized in vitro. by partial digestion of the in vitro transcripts using s1 and cobra venom nuclease as probes of mrna conformation, the analysis was extended to reveal single-stranded and double-stranded regions, respectively, which ...19852414456
determination of specific dna strand discontinuities with nucleotide resolution in exponentionally growing bacteria harboring rolling circle-replicating plasmids.plasmid replication by the rolling circle mechanism and conjugative transfer of plasmids require the generation of a specific strand discontinuity in the dna. in both processes cleavage at the so-called nic site is catalyzed by plasmid-encoded proteins. the strand discontinuities at the conjugative origins of transfer of plasmid pe194 and pmv158 were determined in bacillus subtilis and streptococcus pneumoniae, respectively, with a recently developed runoff dna synthesis assay. the positions of ...19979231429
plus-origin mapping of single-stranded dna plasmid pe194 and nick site homologies with other plasmids.staphylococcus aureus plasmid pe194 manifests a natural thermosensitivity for replication and can be established in several species, both gram positive and gram negative, thus making it attractive for use as a delivery vector. like most characterized plasmids of gram-positive bacteria, pe194 generates single-stranded dna. the direction of pe194 replication is clockwise, as determined by the strandedness of free single-stranded dna. significant homology exists between a 50-base-pair sequence in t ...19902198265
replication genes of plasmid pe194-cop and repf: transcripts and encoded proteins.in vivo transcription of the replication region of plasmid pe194 yeidls two classes of mrnas that encode cop and repf proteins, respectively. these transcripts are oriented 5' to 3' exclusively in the clockwise direction on the standard map. the cop region contains an open reading frame capable of encoding a 55-amino-acid protein that was demonstrated electrophoretically as a 6-kilodalton product synthesized in bacillus subtilis minicells and chemically by n-terminal sequencing of a 116-kilodalt ...19902120193
genetic analysis of a lactococcal plasmid replicon.the sequence and genetic organization was determined of the 2508 bp lactococcal portion of pfx2, which was derived from a cryptic lactococcus lactis subsp. lactis plasmid and used as the basis for construction of a series of lactococcal vectors. a lactococcal plasmid plus origin and two replication protein-coding regions (repa and repb) were located. repa has a helix-turn-helix motif, a geometry typical of dna-binding proteins. repb shows a high degree of homology to the plasmid replication init ...19911904536
cis-inhibitory elements in the pt181 replication system.we report here the existence of a pair of sequence elements in plasmid cointegrates that together block the function of pt181 plasmid replication origins in cis. the study is an outgrowth of the use of plasmid pe194 as a vector for the analysis of the pt181 replication system. we have observed that whereas the isolated pt181 replication origin is fully functional when cloned to pe194, it is inactive when the entire pt181 plasmid genome is cloned. this cis-inhibition is relieved by deletion of al ...19921615066
[determination of the minimal length dna homologous region required for plasmid integration into the bacillus subtilis chromosome via homologous recombination].with a view to determine a minimal sequence length of homology necessary for rece-dependent homologous recombination in bacillus subtilis cells, we developed a system, based on interaction between plasmid replicon and bacterial chromosome. recombination frequencies were measured between ts plasmid pe194 derivatives carrying chromosomal beta-glucuronidase gene (bgls) fragments of various length, and a bacterial chromosome. the homologous recombination events resulted in bgls gene disruption. appr ...19921427056
imprecise excision of plasmid pe194 from the chromosomes of bacillus subtilis pe194 insertion strains.plasmid pe194 has been shown to be rescued by integration after cultivation of infected bacillus subtilis rece4 cells at a restrictive high temperature. the plasmid is also spontaneously excised from the chromosome at a low frequency by precise or imprecise excision (j. hofemeister, m. israeli-reches, and d. dubnau, mol. gen. genet. 189:58-68, 1983). we have investigated nine excision plasmids, carrying insert dna 1 to 6 kbp in length, either in a complete pe194 or in a partially deleted pe194 c ...19921400250
the dna sequence of gamma-glutamyltranspeptidase gene of bacillus subtilis (natto) plasmid puh1.the gamma-glutamyltranspeptidase (gamma-gtp) gene of bacillus subtilis (natto) plasmid designated puh1, which is responsible for polyglutamate production, has been cloned and the nucleotide sequence determined. the sequence contains a single open-reading frame stretching for 1260 bp with a relative molecular mass of 49,356. putative -35 and -10 sequences, ttcaaa and tattat, were observed as the consensus sequence for the promoter recognized by the sigma 43 rna polymerase of b. subtilis, and the ...19921369479
batch cultures of recombinant lactococcus lactis subsp. lactis in a stirred fermentor. i. effect of plasmid content on bacterial growth and on genetic stability in pure cultures.the effect of plasmid introduction into lactococcus lactis subsp. lactis il2661 on the growth of this strain and on plasmid stability was studied in pure batch cultures. the plasmids used (coding for erythromycin or chloramphenicol resistance) were the following: pil205 (42 kb), pil252 (4.6 kb, 6-9 copies), pil253 (4.8 kb, 45-85 copies) and pe194 (inserted in the chromosome). growth and acidification of l. lactis subsp. lactis il2661 were similar to those of the derived recombinant lactococci. t ...19921368909
hypersecretion of a cellulase from clostridium thermocellum in bacillus subtilis by induction of chromosomal dna amplification.we have inserted a dna fragment composed of (i) the promoter and the export signal of the bacillus subtilis levansucrase gene; (ii) the sequence encoding the mature part of the clostridium thermocellum endoglucanase a gene in a specific site of the b. subtilis chromosome. the insert was flanked by directly repeated pbr322 sequences of 3.9 kb. plasmid pe194, which has a thermosensitive replication, was integrated adjacent to one of the repeats. when the integrated plasmid was allowed to replicate ...19901367437
genetic manipulation of bacillus amyloliquefaciens.application of modern gene technology to strain improvement of the industrially important bacterium bacillus amyloliquefaciens is reported. several different plasmid constructions carrying the alpha-amylase gene (amye) from b. amyloliquefaciens were amplified in this species either extrachromosomally or intrachromosomally. the amye gene cloned on a pub110-derived high copy plasmid pkth10 directed the highest yields both in rich laboratory medium and in crude industrial medium. the alpha-amylase ...19911367238
new thermosensitive plasmid for gram-positive bacteria.we isolated a replication-thermosensitive mutant of the broad-host-range replicon pwv01. the mutant pve6002 is fully thermosensitive above 35 degrees c in both gram-negative and gram-positive bacteria. four clustered mutations were identified in the gene encoding the replication protein of pve6002. the thermosensitive derivative of the related plasmid pe194 carries a mutation in the analogous region but not in the same position. derivatives of the thermosensitive plasmid convenient for cloning p ...19921324906
n-methyl transferase of streptomyces erythraeus that confers resistance to the macrolide-lincosamide-streptogramin b antibiotics: amino acid sequence and its homology to cognate r-factor enzymes from pathogenic bacilli and cocci.the nucleotide sequence of a structural gene erme for ribosomal rna (rrna) n6-amino adenine n-methyl transferase (nmt) of streptomyces erythraeus, cloned by thompson et al. [gene 20 (1982) 51-62], has been determined. the nmt amino acid (aa) sequence deduced from the nucleotide sequence contains extensive homology to aa sequences of cognate nmts specified by: (1) plasmid pe194 from staphylococcus aureus, 30% g + c, ermc; (2) plasmid pam77 from streptococcus sanguis, 43% g + c; as well as to (3) ...19853934045
illegitimate recombination in bacillus subtilis: nucleotide sequences at recombinant dna junctions.the illegitimate integration of plasmid pgg20 (the hybrid between staphylococcus aureus plasmid pe194 and escherichia coli plasmid pbr322) into the bacillus subtilis chromosome was studied. it was found that nucleotide sequences of both parental plasmids could be involved in this process. the recombinant dna junctions between plasmid pgg20 and the chromosome were cloned and their nucleotide sequences were determined. the site of recombination located on the pbr322 moiety carried a short region ( ...19873123895
plasmid replication stimulates dna recombination in bacillus subtilis.the effects of plasmid replication on the frequency of homologous recombination have been investigated. for that purpose bacillus subtilis strains that carry in their chromosome directly repeated dna sequences, and an integrated copy of plasmid pe194 either proximal or distal to the repeats, were constructed. the repeat consists either of 3.9 x 10(3) base pbr322 sequences or 2.1 x 10(3) base b. subtilis chromosomal sequences. as plasmid pe194 is naturally thermosensitive for replication, the act ...19873116269
posttranscriptional regulation of an erythromycin resistance protein specified by plasmic pe194.induction of the synthesis of a plasmid-encoded polypeptide (e3) by erythromycin is known to be required for the inducible expression of resistance to the macrolide-lincosamide-streptogramin b group of antibiotics in bacillus subtilis strains carrying the plasmid pe194. this resistance is mediated by a specific n6-dimethylation of adenine in the 23s rrna of the large ribosomal subunit. we show in this report that e3 induction is regulated posttranscriptionally in the sense that it can occur when ...19806159624
conformational alteration of mrna structure and the posttranscriptional regulation of erythromycin-induced drug resistance.the dna sequence of the ermc gene of plasmid pe194 is presented. this determinant is responsible for erythromycin-induced resistance to the macrolide-lincosamide-streptogramin b group of antibiotics and specifies a 29,000 dalton inducible protein. the locations of the ermc promoter, as well as that of a probable transcriptional terminator, are established both from the sequence and by transcription mapping. the sequence contains an open reading frame sufficient to encode the previously identifie ...19806162157
replication and incompatibility properties of plasmid pe194 in bacillus subtilis.pe194, a 3.5-kilobase multicopy plasmid, confers resistance to the macrolide-lincosamide-streptogramin b antibiotics in bacillus subtilis. by molecular cloning and deletion analysis we have identified a replication segment on the physical map of this plasmid, which consists of about 900 to 1,000 base pairs. this segment contains the replication origin. it also specifies a trans-acting function (rep) required for the stable replication of pe194 and a negatively acting copy control function which ...19826290448
a complex attenuator regulates inducible resistance to macrolides, lincosamides, and streptogramin type b antibiotics in streptococcus sanguis.macrolide-lincosamide-streptogramin b resistance specified by streptococcus sanguis plasmid pam77 involves an adenine methylase, whose synthesis, demonstrable both phenotypically and by analysis of methionine-labeled proteins made in bacillus subtilis minicells, is inducible by erythromycin, lincomycin, and streptogramin type b antibiotics. localization of the methylase structural gene, including its control region in dna fragments obtained with restriction endonucleases, has been deduced from d ...19836406429
posttranscriptional modification of mrna conformation: mechanism that regulates erythromycin-induced resistance.the nucleotide sequence of a gene in plasmid pe194 responsible for erythromycin-induced resistance, including regulation of the resistance phenotype, is reported. a dna fragment from plasmid pe194, obtained by digestion with taq i restriction endonuclease, was cloned in bacillus subtilis by using pc194 as the plasmid cloning vector. erythromycin-resistant, inducible transformant clones containing the taq i fragment a were obtained in which the expression of resistance was similar to that found i ...19806938954
characterization of an erythromycin resistance (erm) plasmid in streptococcus pyogenes.three erythromyxin-resistant swedish isolates of streptococcus pyogenes, representing different t-types, were studied. two of the strains showed constitutive high-level (mic > 200 micrograms/ml) and one showed moderate (mic 6.4 micrograms/ml) resistance; the latter strain was sensitive to lincosamide and clindamycin, and resistance was not induced by erythromycin. in each of the strains, a plasmid with an estimated mw of 17.6 +/- 0.9 x 10(6) was isolated in addition to smaller cryptic plasmids. ...19957695892
regulation of plasmid pe194 replication: control of cop-repf operon transcription by cop and of repf translation by countertranscript rna.the cop-rep region of plasmid pe194 contains two tandem structural genes, cop and repf, as well as the plus and minus origins of replication. the two structural genes comprise an operon whose expression is repressed by the binding of cop protein to a 28-bp inverted complementary repeat sequence that overlaps the cop-repf promoter. from its position relative to the promoter and the experimentally determined footprint made by the cop protein, the 28-bp inverted complementary repeat sequence is pre ...19948051016
molecular characterization of a plasmid-borne (pgt633) erythromycin resistance determinant (ermgt) from lactobacillus reuteri 100-63.lactobacillus reuteri 100-63 contains a 9.8 kb plasmid (pgt633) encoding resistance to the macrolide-lincosamide-streptogramin (mls) type b antibiotics. the restriction endonucleases acci, bamhi, bcli, ecori, ecorv, hhai, hindii, hpai, kpni, sali, and sspi were employed to establish a physical map of pgt633. next, genetic transfer experiments were conducted to establish the host range of pgt633. the results revealed that pgt633 replicated autonomously and encoded constitutive resistance to eryth ...19948171126
[construct of the stable-produced strain for the thermostable alpha-amylase].the plasmid pe194 as a vector is used to subclone the thermostable alpha-amylase gene of b. licheniformis and construct recombinant plasmid pnw102. the plasmid pnw102 was transduced into b. subilis bf 7658 by bacteriophage pbs1. the b. subtilis bf7658 (pnw102) strain was treated at non-permissive temperature for a long time, and obtained many recombinant strains. this is the homologous recombination results between alpha-amylase genes of pnw102 and bf7658. the homologous recombination occurs at ...19938373628
[behavior of heterologous recombinant plasmid pcet in cells of bacillus anthracis].recombinant plasmid pcet was constructed in vivo in cells of enteric and hay bacillus, on the basis of plasmids pc194, and pbc16. plasmid pcet inherits marker genes of antibiotic resistance from parental plasmids. anthrax cells were transformed by the recombinant plasmid developed. the behavior of this plasmid was studied in vegetative bacillus anthracis cells, which did not pass through the sporulation stage and were cultivated at temperatures permissive for the replicon of plasmid pe194. under ...19968754064
expression of cereolysine ab genes in bacillus anthracis vaccine strain ensures protection against experimental hemolytic anthrax infection.the cereolysin ab genes from bacillus cereus vkm-b164 have been expressed in bacillus anthracis strains: virulent h-7 (pxo1, pxo2), vaccine sti-1 (pxo1), 221 (without its own plasmids). expression was achieved by cloning the genes in a high copy number plasmid pe194. this construct was integrated with host genomes in amplified form. gold hamsters were vaccinated with parental and recombinant b. anthracis sti-1 and 221 strains and challenged with virulent ones subcutaneously. gold hamsters vaccin ...19979413092
molecular analysis of the macrolide-lincosamide resistance gene region of a novel plasmid from staphylococcus hyicus.resistance to macrolides and lincosamides in staphylococcus hyicus has been shown to be encoded by a 4.0-kb plasmid designated pses21. it differed distinctly in its restriction map from all other staphylococcal macrolide resistance plasmids reported so far. southern blot hybridisation with gene probes specific for staphylococcal erm genes demonstrated that the macrolide resistance gene belonged to hybridisation class c. analysis of the ermc gene revealed that the deduced amino-acid sequence of t ...19989449951
lagging strand replication of rolling-circle plasmids: specific recognition of the ssoa-type origins in different gram-positive bacteria.many bacterial plasmids replicate by a rolling-circle mechanism that involves the generation of single-stranded dna (ssdna) intermediates. replication of the lagging strand of such plasmids initiates from their single strand origin (sso). many different types of ssos have been identified. one group of ssos, termed ssoa, which have conserved sequence and structural features, function efficiently only in their natural hosts in vivo. to study the host specificity of sso sequences, we have analyzed ...19989724733
purification and characterization of cop, a protein involved in the copy number control of plasmid pe194.cop protein has been overexpressed in escherichia coli using a t7 rna polymerase system. purification to apparent homogeneity was achieved by the sequential chromatography on ion exchange, affinity chromatography, and reverse phase high performance liquid chromatography system. the molecular weight of the purified cop was estimated as 6.1 kda by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page). but the molecular mass of the native state cop was shown to be 19 kda by an analyt ...19989875446
the hyaluronate lyase of staphylococcus aureus - a virulence factor?the hyaluronate lyase (hl) gene of staphylococcus aureus 8325-4 (hysa) was inactivated in vitro with the insertion of the erythromycin determinant, ermc, from plasmid pe194. the hysa : : ermc mutation was introduced into s. aureus via a temperature-sensitive shuttle vector, where it underwent homologous recombination with the wild-type (w.t.) allele. the insertion of ermc in the chromosomal hysa locus was confirmed by southern blot hybridization and the loss of hl activity was demonstrated macro ...200415184586
incompatibility of lactobacillus vectors with replicons derived from small cryptic lactobacillus plasmids and segregational instability of the introduced vectors.three new lactobacillus vectors based on cryptic lactobacillus plasmids were constructed. the shuttle vector plp3537 consists of a 2.3-kb plasmid from lactobacillus pentosus md353, an erythromycin resistance gene from staphylococcus aureus plasmid pe194, and puc19 as a replicon for escherichia coli. the vectors plpe317 and plpe323, which do not contain e. coli sequences, were generated by introducing the erythromycin resistance gene of pe194 into a 1.7- and a 2.3-kb plasmid from l. pentosus md35 ...199116348515
development of shuttle vectors for evaluation of essential regulator regulated gene expression in staphylococcus aureus.we describe the construction of a series of shuttle vectors for staphylococcus aureus. in order to determine transcriptional regulation by essential regulators, we constructed promoterless luxabcde reporter system using a tetr-regulated antisense rna expression vector, pjyj909, which is composed of s. aureus plasmid pe194, the gram(-) plasmid puc18, a tetr regulatory cassette, and pxyl/teto-driven yhcs antisense expression construct. the reformed shuttle vector was utilized to construct an opuca ...200919245820
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