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methanol production by mycobacterium smegmatis.mycobacterium smegmatis cells produce [3h]methanol when incubated with [methyl-3h]methionine. the methanol is derived from s-adenosylmethionine rather than methyltetrahydrofolate. m. smegmatis cells carboxymethylate several proteins, and some of the methanol probably results from their demethylation, but most of the methanol may come from an unidentified component with a high gel mobility. although methanol in the medium reached 19 microm, it was not incorporated into the methylated mannose poly ...19883343224
order of enzymic incorporation of o-methyl groups into the o-methyl-d-glucose-containing polysaccharide of mycobacterium smegmatis. a tritium-labelling study.the order of enzymic incorporation of o-methyl groups into the o-methyl-d-glucose-containing polysaccharide (mgp) of mycobacterium smegmatis, 3mg(j)----g(i)----g(h) ----g(g)----6mg(f)----(gmg)9(e)----[g(l)----g(d)]----g(c) ----[g(k)----g(b)]----g(a)----ga, where g is d-glucose, 3mg is 3-o-methyl-d-glucose, 6mg is 6-o-methyl-d-glucose, and ga is d-glyceric acid, was studied by incubating cultures of m. smegmatis with l-[3h-me]methionine for various times. mgp was then extracted from the cells, an ...19883370650
mode of action of deoxypheganomycin d on mycobacterium smegmatis atcc 607.deoxypheganomycin d, a specific inhibitor of mycobacteria, inhibits the growth in vitro of mycobacterium smegmatis atcc 607 (m. 607) bacteriostatically at concentrations as high as 7 x 10(-5) m. it shows no cross-resistance to paromomycin, capreomycin, viomycin, streptothricin, kanamycin and streptomycin. deoxypheganomycin d at 2.8 x 10(-7) m where the cell growth of m. 607 is only partially inhibited does not significantly inhibit dna, rna or protein synthesis but leads to marked decrease (13% ...19883384753
human disease due to mycobacterium smegmatis.mycobacterium smegmatis is a rapidly growing environmental species not considered a human pathogen. we identified 22 human isolates of m. smegmatis from australia and the southern united states: 19 were from skin or soft-tissue infections, and none were from urine or the male genital tract. these isolates closely resembled mycobacterium fortuitum, except for a negative three-day arylsulfatase test; growth at 43-45 c; a low semiquantitative catalase test; and, in 50% of isolates, a late-developin ...19883392420
rat kidney l-2-hydroxyacid oxidase. structural and mechanistic comparison with flavocytochrome b2 from baker's yeast.hydroxyacid oxidase from rat kidney is an fmn-dependent enzyme that catalyzes the oxidation of l-alpha-hydroxy acids as well as, more slowly, that of l-alpha-amino acids. we report here a modified purification method for the enzyme, which is found to possess one cofactor per subunit of mr 39,000. determination of its n-terminal sequence suggests the protein is homologous to spinach glycolate oxidase and baker's yeast lactate dehydrogenase. in the presence of a hydroxy acid and of bromopyruvate, ...19883061453
lysogeny and transformation in mycobacteria: stable expression of foreign genes.requisite to a detailed understanding of the molecular basis of bacterial pathogenesis is a genetic system that allows for the transfer, mutation, and expression of specific genes. because of the continuing importance of tuberculosis and leprosy worldwide, we initiated studies to develop a genetic system in mycobacteria and here report the use of two complementary strategies to introduce and express selectable genetic markers. first, an escherichia coli cosmid was inserted into the temperate myc ...19882842799
identification of a salvage pathway for d-arabinose in mycobacterium smegmatis.extracts of mycobacterium smegmatis, which was adapted to growth in synthetic medium containing d-arabinose as sole carbon source, catalyzed the nadph-mediated reduction of d-arabinose to d-arabitol. when arabinose-adapted bacteria were transferred to glycerol medium, resumption of growth was accompanied by a sharp drop in the specific activity of this enzyme. moreover, extracts of cells grown in d-arabinose medium contained large amounts of an nad+-linked pentitol dehydrogenase, as compared to ...19883126069
purification and reconstitution of the electron transport components for 6-deoxyerythronolide b hydroxylase, a cytochrome p-450 enzyme of macrolide antibiotic (erythromycin) biosynthesis.the hydroxylation of 6-deoxyerythronolide b (6d) to erythronolide b, a step in the biosynthesis of the 14-membered macrolide antibiotic erythromycin a by saccharopolyspora erythraea, is catalyzed by a cytochrome p-450 monooxygenase that requires two electron transport proteins for the function of this terminal hydroxylase (a. shafiee and c. r. hutchinson, biochemistry 26:6204-6210, 1987). two flavoproteins and an iron-sulfur protein (erythrodoxin) were purified from s. erythraea ca340 and shown ...19883127376
microbial metabolism of phenelzine and pheniprazine.phenelzine and pheniprazine were used as substrates for metabolic studies with cunninghamella echinulata and mycobacterium smegmatis. metabolites were identified by means of gas-liquid chromatography and mass spectrometry. 1-acetyl-2-(2-phenylethyl)-hydrazine and 1-acetyl-2-(1-methyl-2-phenylethyl)hydrazine were the major products of c. echinulata metabolism of phenelzine and pheniprazine, respectively. in addition, m. smegmatis produced a second metabolite from each substrate; these metabolites ...19882892108
regulation of ornithine decarboxylase from mycobacterium smegmatis.the activity of ornithine decarboxylase in mycobacterium smegmatis is regulated by a novel macromolecular inhibitor--a ribonucleic acid. addition of polyamines to the growth medium enhances the level of this inhibitor, suggesting that the level of this negative modulator changes in response to the intracellular concentration of polyamines. thus, while other modes of regulation may be operational, the control by polyamines at the transcriptional level leading to the generation of a specific rna i ...19882456036
study on rrna genes in mycobacterium smegmatis.the number of rrna genes in mycobacterium smegmatis was examined by hybridization of bamhi and sali digests of chromosomal dna with 3'-end-labeled 5s, 16s, 23s rrna and trna. each rna probe gave two hybridization bands. the psti fragments of 6.6 kilobases were cloned to pbr322. the cloned dna was characterized by restriction endonuclease mapping, dna-rna hybridization, and the r-loop technique.19882467181
cloning and restriction analysis of ribosomal rna genes from mycobacterium smegmatis.a genomic library of mycobacterium smegmatis dna was constructed in phage embl3. a clone (gamma hb85) containing rrna genes was isolated using as probes, fragments of e. coli rrna cistron b. this cloned dna fragment was mapped by restriction analysis and was shown to contain one complete set of rrna genes (rrna a). the physical mapping of the second set of rrna genes of m. smegmatis (rrna b) was done by restriction analysis of total chromosomal dna. the two sets of rrna genes showed highly conse ...19892470636
synthesis of alpha 1----6-mannooligosaccharides in mycobacterium smegmatis. function of beta-mannosylphosphoryldecaprenol as the mannosyl donor.incubation of a membrane fraction from mycobacterium smegmatis cells with gdp-mannose and free mannose at ph 7 in presence of mg2+ ions resulted in the formation of a series of alpha 1----6-linked mannooligosaccharides with up to 12 mannoses. the membrane fraction also catalyzed incorporation of mannose from gdp-mannose into a lipid-soluble product with the properties of a mannosyl phospholipid. a similar product was formed by the incubation of the membrane protein with decaprenol phosphate and ...19892480954
metabolism of aspartate in mycobacterium smegmatis.mycobacterium smegmatis grows best on l-asparagine as a sole nitrogen source; this was confirmed. [14c]aspartate was taken up rapidly (46 nmol.mg dry cells-1.h-1 from 1 mm l-asparagine) and metabolised to co2 as well as to amino acids synthesised through the aspartate pathway. proportionately more radioactivity appeared in the amino acids in bacteria grown in medium containing low nitrogen. activities of aspartokinase and homoserine dehydrogenase, the initial enzymes of the aspartate pathway, we ...19892496980
transformation of mycobacterium smegmatis with e. coli plasmids.one limiting factor in the studies of tuberculosis and leprosy is the lack of a versatile system for genetic analysis and manipulation of mycobacteria. one strategy used in constructing a plasmid vector for transforming mycobacterium smegmatis was to insert fragments of a mycobacterial plasmid into an escherichia coli plasmid. we found that the parental e. coli plasmid is capable of self-replication in m. smegmatis yielding chloramphenicol-resistant colonies. plasmids from different passages of ...19892503993
isolation and first characterization of a temperate phage growing on mycobacterium smegmatis and m. bovis-bcg. 19892503997
germicidal effectiveness of dialox, a new stable peroxyacetic acid solution, in the re-use of high-flux dialysers.in this study we evaluate the effectiveness of a newly available peroxyacetic acid solution (dialox) as a disinfecting agent in the re-use of highly permeable dialysers. the germicidal properties of dialox were tested in an in vitro trial on previously used haemodiafilters (hf80, fresenius) highly contaminated with pseudomonas aeruginosa, mycobacterium smegmatis or sporulated bacillus cereus. complete freedom from bacterial contamination was observed 5 min after the reprocessing treatment on a r ...19892516880
synthesis and reactivity of the oxovanadium(iv) complexes of two n-o donors and potentiation of the antituberculosis activity of one of them on chelation to metal ions: part iv.a new series of oxovanadium(iv) complexes of two aromatic acidhydrazides (bh and ah) have been reported. of these two donors, ah is known to possess considerable in vitro antitubercular activity. at ph 2-4, oxometal complexes of the type [vo(bh/ah)2so4].nh2o (n = 1, 0) and [vo(bh/ah)(c2o4)h2o].h2o (bh = c6h5conhnh2 and ah = (2-nh2)c6h4.co.nhnh2) were obtained. reactions of [vo(bh/ah)(c2o4)h2o].h2o with a monodentate lewis base lead to the isolation of metal-ligand complexes [vo(bh/ah)(c2o4)l].nh ...19892547895
physical and chemical characterization of glutamine synthetase purified from mycobacterium phlei.glutamine synthetase (l-glutamate: ammonia ligase [adp forming]) [ec 6.3.1.2] has been purified from a gram-positive, acid-fast bacterium, mycobacterium phlei, by simple procedures with 57% recovery. the enzyme resembled that from mycobacterium smegmatis in the subunit size (56,000), molecular weight (670,000), amino acid composition, the amino acid sequence of the nh2-terminal, and the secondary structure. the enzyme activity was regulated by adenylylation of each subunit in the dodecameric mol ...19892569461
the cell envelope of mycobacterium smegmatis: cytochemistry and architectural implications.in sections stained for localizing both carbohydrates (thiery's method) and lipids (the o.t.o. method), the cell envelope of mycobacterium smegmatis appeared to consists of an asymmetric cytoplasmic membrane surrounded by a three-layered cell wall. the outer layer of the cytoplasmic membrane was found to contain more glycoconjugate molecules (probably phosphatidyl inositol mannosides) than the inner one. the cell wall consists of the peptidoglycan (the innermost layer) surrounded by a layer cont ...19892599362
determination and evolutionary significance of nucleotide sequences near to the 3'-end of 16s ribosomal rna of mycobacteria.the nucleotide sequence at the 3'-end of 16sr-rna (nucleotides 1305-1508) was determined, by the primer extension method, for mycobacterium smegmatis, mycobacterium tuberculosis and mycobacterium vaccae, in addition to mycobacterium leprae. no differences in nucleotide sequence were detected, indicating that this region of 16srrna is highly conserved among mycobacteria. the nucleotide sequence common to the four above-mentioned mycobacteria differs from that reported for species of other genera. ...19892612878
phospholipid composition of mycobacterium smegmatis susceptible and resistant to antitubercular drugs.the phospholipid composition, distribution and metabolism in mono drug resistant mutants towards antitubercular drugs, viz, streptomycin, ethambutol and isoniazid, were investigated. though their total phospholipid content was not altered significantly, changes were observed in their individual phospholipid content. reduced biosynthesis and degradation of phospholipids (monitored by pulse and chase technique using [32p]orthophosphoric acid as a precursor) was observed in all the mutants studied. ...19892620911
partial characterization of mycobacterium fortuitum and mycobacterium smegmatis auxotrophs by syntrophism using bacillus subtilis.syntrophism (cross-feeding) could be demonstrated between mutants of mycobacterium fortuitum and mycobacterium smegmatis, and previously characterized mutants of bacillus subtilis, auxotrophic for arginine, histidine, lysine or phenylalanine. based on this cross-feeding data, the possible site of blockage in the biosynthetic pathways of the mutants could be inferred.19892632668
fad-dependent malate dehydrogenase from mycobacterium smegmatis: activation of the lipid-depleted inactive enzyme by a phospholipid analogue, di (triethyleneglycoltetradecylether) phosphate.a novel phospholipid analogue, di (triethyleneglycol-n-tetradecylether) phosphate was synthesized and its activation ability for a phospholipid-requiring enzyme, mycobacterium smegmatis malate dehydrogenase, was examined. the results showed that the newly-synthesized phospholipid analogue a high ability, nearly equal to that of natural beef heart cardiolipin, for the activation of the lipid-depleted inactive enzyme; whereas both simple di-n-octylphosphate and di-n-tetradecylphosphate were found ...19892635863
mycobacteriophage vector systems.successful application of molecular genetic approaches to the study of mycobacteria necessitates the introduction of recombinant dna molecules into mycobacterial cells. efficient methods of introducing dna into mycobacterium smegmatis protoplasts have been developed, and the construction of mycobacteriophage recombinant dna vectors has been initiated. novel escherichia coli-mycobacterium shuttle vectors, termed shuttle phasmids, have been constructed. these vectors were constructed by inserting ...19892652256
transformation of mycobacterium smegmatis with escherichia coli plasmids carrying a selectable resistance marker.one limiting factor in studies of tuberculosis and leprosy is the difficulty of genetic analysis and manipulation of mycobacteria. two approaches were adopted for the construction of vectors, based on different escherichia coli plasmids and using mycobacterium smegmatis as the host. in both cases we found that the original e. coli plasmid is capable of being replicated in m. smegmatis, yielding chloramphenicol-resistant colonies. one such plasmid has been recovered from a m. smegmatis transforma ...19892654539
modulation of arginine decarboxylase activity from mycobacterium smegmatis. evidence for pyridoxal-5'-phosphate-mediated conformational changes in the enzyme.arginine decarboxylase (arginine carboxy-lyase, ec 4.1.1.19) from mycobacterium smegmatis, tmc 1546 has been purified to homogeneity. the enzyme has a molecular mass of 232 kda and a subunit mass of 58.9 kda. the enzyme from mycobacteria is totally dependent on pyridoxal 5'-phosphate for its activity at its optimal ph and, unlike that from escherichia coli, mg2+ does not play an active role in the enzyme conformation. the enzyme is specific for arginine (km = 1.6 mm). the holoenzyme is completel ...19892667997
antimicrobial and cytotoxic activity of rottlerin-type compounds from hypericum drummondii.hexane extracts of hypericum drummondii showed significant activity against the gram-positive bacteria staphylococcus aureus, bacillus subtilis, and the acid-fast bacterium mycobacterium smegmatis in an agar well diffusion assay. employing bioassay-directed fractionation procedures, four new rottlerin-type compounds (drummondins a, b, c[1-3], and f [4]) were isolated and identified by spectral and physical characterization. the antimicrobial activity of these compounds was comparable to or great ...19892746258
thermally adaptive changes of mycolic acids in mycobacterium smegmatis.the effect of growth temperature on mycolic acid composition in eight strains of mycobacterium smegmatis was investigated by gas chromatography/mass spectrometry. a change in growth temperature from 45 to 20 degrees c caused a shift in the subclass and molecular species composition of mycolic acids. the relative amount of alpha'-mycolic acids to alpha-mycolic acids decreased, and that of hydroxy mycolic acids increased at lower temperatures. moreover, the proportion of shorter-chain species of a ...19892777756
purification and characterization of an extracellular lectin from mycobacterium smegmatis.mycobacteria exist naturally in aggregated form and pathogenic strains colonize macrophages. a lectin has been isolated from the culture broth of m. smegmatis, which may, possibly, have an important role in either or both of these phenomena. the lectin of mr 12,000-14,000 agglutinates erythrocytes from different species, and agglutination is reversed by arabinogalactan isolated from mycobacteria, as well as by yeast mannan. it has a pi of 5.5 and is rich in aspartic and glutamic acid residues.19892806545
inhibition of synthesis of arabinogalactan by ethambutol in mycobacterium smegmatis.ethambutol at 3.0 micrograms/ml inhibited the transfer of label from d-[14c]glucose into the d-arabinose residue of arabinogalactan in whole cells of a drug-susceptible strain of mycobacterium smegmatis. this inhibition began almost immediately after exposure of the cells to the drug. when drug-resistant m. smegmatis was used in a similar experiment, no such drug inhibition was detected. a much higher concentration of ethambutol (greater than 50 micrograms/ml) was required to show this inhibitio ...19892817850
activation of mouse peritoneal macrophages by mannophosphoinositides of mycobacteria.peritoneal macrophages isolated from mannoside-methylated bovine serum albumin (mbsa)-immunized mice showed significantly enhanced phagocytosis of mycobacterium smegmatis compared to control or mbsa-immunized groups. immune macrophages also exhibited bacteriostatic activity against m. smegmatis. pretreatment of mycobacteria with mannoside antibodies did not further alter the phagocytosis and bacteriostatic effect of immune macrophages.19892909862
structural similarities between spinach chloroplast and cytosolic class i fructose 1,6-bisphosphate aldolases : immunochemical and amino-terminal amino acid sequence analysis.immunochemical studies using polyclonal antisera prepared individually against highly purified cytosolic and chloroplast spinach leaf (spinacia oleracea) fructose bisphosphate aldolases showed significant cross reaction between both forms of spinach aldolase and their heterologous antisera. the individual cross reactions were estimated to be approximately 50% in both cases under conditions of antibody saturation using a highly sensitive enzyme-linked immunosorbent assay. in contrast, the class i ...198916667191
presence of gamma glutamyl transferase in mycobacterium smegmatis.the presence of gamma glutamyl transferase (ggt) has been established in mycobacterium smegmatis. the 10,000 x g supernatant demonstrated only hydrolase activity and did not exhibit any transpeptidase activity. most of the transferase activity was recovered in 100,000 x g supernatant demonstrating that ggt is a cytosolic enzyme. maximum activity of ggt was observed at two days of growth and the activity decreased significantly till the seventh day of growth when mycobacteria was grown as station ...19901971749
isolation and characterization of efficient plasmid transformation mutants of mycobacterium smegmatis.recent development of vectors and methodologies to introduce recombinant dna into members of the genus mycobacterium has provided new approaches for investigating these important bacteria. while most pathogenic mycobacteria are slow-growing, mycobacterium smegmatis is a fast-growing, non-pathogenic species that has been used for many years as a host for mycobacteriophage propagation and, recently, as a host for the introduction of recombinant dna. its use as a cloning host for the analysis of my ...19902082148
growth inhibition in vitro of mycobacterium smegmatis by ten n-aryl glycyl hydrazides.n-(4-amino-2-nitro-toluinyl) glycyl hydrazide and n-(biphenyl) glycyl hydrazide partially inhibited the growth of m smegmatis at 20 micrograms/ml and showed a total inhibition at 100 micrograms/ml. replacement by a nitro or halogen group lowered the activity.19902104492
primary structure of a 7fe ferredoxin from streptomyces griseus.the complete primary structure of a streptomyces griseus (atcc 13273) 7fe ferredoxin, which can couple electron transfer between spinach ferredoxin reductase and s. griseus cytochrome p-450soy for nadph-dependent substrate oxidation, has been determined by edman degradation of the whole protein and peptides derived by staphylococcus aureus v8 proteinase and trypsin digestion. the protein consists of 105 amino acids and has a calculated molecular weight, including seven irons and eight sulfurs, o ...19902106913
[cellular adsorption and absorption of antimony (iii) by mycobacterium smegmatis].adsorption studies of sb (iii) as the antimonyl (125sb) tartrate complex using acidified, non-proliferative suspensions of mycobacterium smegmatis show that the uptake of sb by the biomass increases with the external concentration of antimony ([sb]) and decreases, at given concentration, with increasing ph. measurements of sb uptake in the cells under growth conditions in liquid culture indicate that the cellular concentration factor of antimony is of the order of 10 when the concentration of an ...19902114191
efficacies of selected disinfectants against mycobacterium tuberculosis.the activities of 10 formulations as mycobactericidal agents in mycobacterium tuberculosis-contaminated suspensions (suspension test) and stainless steel surfaces (carrier test) were investigated with sputum as the organic load. the quaternary ammonium compound, chlorhexidine gluconate, and an iodophor were ineffective in all tests. ethanol (70%) was effective against m. tuberculosis only in suspension in the absence of sputum. povidone-iodine was not as efficacious when the test organism was dr ...19902121783
[cross-resistance relationship between streptomycin and kanamycin resistances in mycobacterium smegmatis (strain jucho)--comparison of the development patterns of resistances to streptomycin and kanamycin among mycobacterium tuberculosis, mycobacterium avium complex, and mycobacterium smegmatis].the resistance development pattern of mycobacterium smegmatis strain 17023 (jucho) to streptomycin and kanamycin was studied. the medium used was ogawa egg medium, and the level of resistance was determined for each clone derived from single colony by the 'actual count' method. hence, the resistance level was estimated as the highest concentration of drugs, in which small inocula consisting of 20 to 100 colony-forming units could grow after seven days incubation. only one type of resistance muta ...19902127614
gene replacement and expression of foreign dna in mycobacteria.a system that permits molecular genetic manipulation of mycobacteria was developed on the basis of the yeast paradigm of gene replacement by homologous recombination. a shuttle vector that can replicate autonomously at a high copy number in escherichia coli but must integrate into homologous dna for survival in mycobacterium smegmatis was constructed. the vector contains a cole1 origin of replication, antibiotic resistance markers for ampicillin and kanamycin, a nutritional marker (pyrf) that al ...19902153655
antibacterial activity of the leaves of phyllanthus discoideus.the lyophilized aqueous extract (lwe) from the leaves of phyllanthus discoideus was found to show an antibacterial activity. the alkaloid fraction obtained from lwe inhibited the growth of escherichia coli and enterococcus faecium (mic = 1.6 mg/ml), pseudomonas aeruginosa (mic = 0.78 mg/ml), staphylococcus aureus and mycobacterium smegmatis (mic = 0.2 mg/ml). among the alkaloids identified, viroallosecurinine and securinine showed a high activity. viroallosecurinine exhibited a mic of 0.48 micro ...19902156112
aspartate metabolism in mycobacterium avium grown in host tissue and axenically and in mycobacterium leprae.aspartokinase activity was detected in extracts from mycobacterium leprae (recovered from armadillo liver) and in mycobacterium avium grown axenically and in vivo. homoserine dehydrogenase activity was only detected in m. leprae and in m. avium grown axenically. activities, when detected, were 50 to 70% lower in m. leprae or m. avium grown in vivo than in axenically grown m. avium. in these two pathogenic mycobacteria, aspartokinase and homoserine dehydrogenase are subject to feedback inhibition ...19902191078
conjugative transfer of a shuttle plasmid from escherichia coli to mycobacterium smegmatis [corrected].the chimeric plasmid pmy10 containing the origin of replication of pal5000, the origin of replication of pbr322, the origin of transfer of prk2 and a kanamycin resistance gene was constructed and successfully transferred by conjugation from escherichia coli harbouring the helper plasmid prk4.24 into mycobacterium smegmatis. this is the first report of conjugtive transfer of plasmid between e. coli and an acid fast organism.19902199300
iron-regulated envelope proteins of mycobacteria grown in vitro and their occurrence in mycobacterium avium and mycobacterium leprae grown in vivo.several iron-regulated envelope proteins (ireps), 11-180 kda, have been detected in preparations of walls and membranes of mycobacterium smegmatis, in an armadillo-derived mycobacterium (adm) and in m. avium. the same sized proteins from m. vacae appeared under both iron-deficient and iron-sufficient growth conditions. two larger proteins, of 240 and 250 kda, appeared in the membranes of m. smegmatis and m. avium only when grown iron-sufficiently but were constitutively present in both adm and m ...19902202378
genitourinary mycobacteria in infertile egyptian men.forty infertile patients with a preliminary diagnosis of genitourinary tuberculosis were selected for our study when they presented with one or more of the following: (1) personal or family history of tuberculosis, (2) sterile pyuria, (3) voiding urinary symptoms, (4) abnormality in the epididymis, (5) hemospermia, and (6) clinically unexplained obligoathenospermia. direct smear examination by ziehl-neelsen stain for 24-hour urine and freshly ejaculated semen for 3 days as well as culture of mid ...19902209895
isolation and analysis by the reductive-cleavage method of linkage positions and ring forms in the mycobacterium smegmatis cell-wall arabinogalactan.the mycobacterium smegmatis arabinogalactan polysaccharide has been isolated from the cell wall by saponification and extraction to remove lipids and subsequent solubilization by treatment with lysozyme. analysis for neutral sugars demonstrated the presence of d-arabinose and d-galactose in a ratio of 3:1, respectively. reductive cleavage of the fully methylated polysaccharide in the presence of triethylsilane and trimethylsilyl trifluoromethanesulfonate and subsequent acetylation in situ gave s ...19902224905
high-performance liquid chromatography patterns of mycolic acids as criteria for identification of mycobacterium chelonae, mycobacterium fortuitum, and mycobacterium smegmatis.rapidly growing mycobacteria of clinical significance were identified by mycolic acids detected with high-performance liquid chromatography. mycolic acids from whole cells were extracted, derivatized, and detected by a modified high-performance liquid chromatography procedure in less than 3 h. use of an internal standard allowed differentiation of mycobacterium chelonae and mycobacterium fortuitum by comparison of relative retention times. peak height ratios were used for subidentification of m. ...19902229390
killing of mycobacterium smegmatis by macrophages from genetically susceptible and resistant mice.the bactericidal function of macrophages was investigated in congenic mice expressing the phenotype of susceptibility (b10.a, bcgs) or resistance (b10.abcgr) to mycobacterial infection. when splenic and peritoneal macrophages from these two mouse strains were infected in vitro with mycobacterium smegmatis, the bcgr macrophages were shown to inactivate m. smegmatis more efficiently than their bcgs congenic counterparts. the mechanisms of this superior antimycobacterial activity was studied furthe ...19902294152
cross-reactivity and sequence homology between the 65-kilodalton mycobacterial heat shock protein and human lactoferrin, transferrin, and dr beta subsets of major histocompatibility complex class ii molecules.immunogold ultracytochemistry and western immunoblotting showed that polyclonal antibodies against human lactoferrin bind to the highly immunogenic 65-kilodalton (kda) heat shock protein of mycobacteria. the fast-growing mycobacterial species mycobacterium smegmatis showed a higher density of these receptors for antilactoferrin sera than the slow-growing m. avium. polyclonal antibodies against mycobacteria (m. bovis bcg) recognized human lactoferrin. comparison of the amino acid sequence of lact ...19902323824
l-lactate 2-monooxygenase from mycobacterium smegmatis. cloning, nucleotide sequence, and primary structure homology within an enzyme family.l-lactate 2-monooxygenase catalyzes the oxidation of l-lactate to acetate and carbon dioxide. the catalytic mechanism has been extensively investigated but very little is known about which amino acid residues may play a role in catalysis. as a first step toward this goal, the gene for this protein from mycobacterium smegmatis has been cloned and sequenced. peptide sequencing data for l-lactate 2-monooxygenase was used to construct three sets of fully redundant tetradecamer oligonucleotide probes ...19902324094
effect of ethambutol on the phospholipids of ethambutol susceptible and resistant strains of mycobacterium smegmatis atcc 607.effect of ethambutol (emb) on phospholipid composition and metabolism of emb-susceptible and emb-resistant strains of m. smegmatis atcc 607 was studied. treatment with ethambutol had different effect in both the strains resulting in decreased total phospholipid and cardiolipin content in emb-susceptible strain and increased content in emb-resistant strain, with no effect on fatty acyl group composition. these changes were further corroborated by the use of [1-14c]sodium acetate in these studies.19902341164
trna genes in mycobacteria: organization and molecular cloning.dnas from nine mycobacteria cleaved with restriction endonucleases were hybridized with cdna probes synthesized to trnas from mycobacterium tuberculosis and mycobacterium smegmatis. the trna genes are conserved, but their gross genomic organization has diverged in six of the nine species examined. organisms of the m. tuberculosis h37ra and h37rv-m. bovis bcg complex appeared to have identical trna gene organization and were indistinguishable from each other. m. tuberculosis and m. smegmatis trna ...19902345129
identification, sequencing, and expression of mycobacterium leprae superoxide dismutase, a major antigen.the gene encoding a major 28-kilodalton antigen of mycobacterium leprae has now been sequenced and identified as the enzyme superoxide dismutase (sod) on the basis of the high degree of homology with known sod sequences. the deduced amino acid sequence shows 67% homology with a human manganese-utilizing sod and 55% homology with the escherichia coli manganese-utilizing enzyme. the gene is not expressed from its own promoter in e. coli but is expressed from its own promoter in mycobacterium smegm ...19901692812
transfer rna genes in mycobacteria: organization and molecular cloning.dnas from nine mycobacterial species were cleaved with different restriction endonucleases and hybridized with cdna probes synthesized to total transfer rnas (trnas) from mycobacterium smegmatis and m. tuberculosis. the hybridization data indicate that trna genes are conserved but their gross genomic organization has diverged in six of the nine species examined. species of the mtb complex appeared to have identical trna gene organization. hybridization with cdnas synthesized to 23s plus 16s rrna ...19901701560
immobilization of fatty acid synthetase from mycobacterium smegmatis by radiation-induced polymerization.fatty acid synthetase of type i from mycobacterium smegmatis was immobilized by radiation-induced polymerization of 2-hydroxyethyl methacrylate (hema) in the presence of trimethylolpropane trimethacrylate (tmptma). the stability of immobilized synthetase toward low ionic strength increased in comparison with the free form, but the stabilities of immobilized preparations assessed by ph and temperature were identical to those of the free form. the apparent km of immobilized enzyme for acetyl-coa a ...19901368562
fluorescein diacetate and ethidium bromide staining to determine the viability of mycobacterium smegmatis and escherichia coli.the ability of the fluorescein diacetate and ethidium bromide fluorescent staining method to assess the percentage of viable bacterial cells in suspension was compared with the plate counting method. mycobacterium smegmatis and escherichia coli bacterial cell suspensions were incubated at 60 degrees c. at different time intervals samples were taken and the percentage of viable cells in each sample was assessed by the fluorescent staining method and compared with the plate counting method. the fl ...19911724546
defective mycolic acid biosynthesis in a mutant of mycobacterium smegmatis.a mutant of mycobacterium smegmatis defective in mycolic acid biosynthesis was isolated following chemical mutagenesis. fatty acids were extracted from the mutant and subjected to structural analysis by thin-layer chromatography and high-performance liquid chromatography (hplc) of both methyl and p-bromophenacyl ester derivatives. thin-layer chromatography did not show the presence of any fatty acid of rf comparable to that of standard methyl mycolate. the hplc profile revealed a broad peak in t ...19911748873
complexes of mycobactin from mycobacterium smegmatis with scandium, yttrium and lanthanum.the interaction of cations of group iiib elements (sc, y, la) with mycobactin s in ethanol leads to the formation of 1:1 complexes which closely resemble the known aluminium compound with respect to ultraviolet absorption and fluorescence emission spectra. determination of molar stoichiometry by spectrophotometry shows that this method can be conveniently applied to the estimation of purity in mycobactin samples. hydrolytic dissociation measurements based on aqueous extraction of the labelled co ...19911777355
transformation of mycobacterium aurum and mycobacterium smegmatis with the broad host-range gram-negative cosmid vector pjrd215.the transformation of mycobacterium aurum and mycobacterium smegmatis with the gram-negative rsf1010-derived cosmid pjrd215 is described. the plasmid is stably maintained in both species and the antibiotic resistance determinants for kanamycin and streptomycin are expressed. southern blot analysis shows that rearrangements take place both in m. aurum and in m. smegmatis. the use of pjrd215 in mycobacterial cloning systems is discussed.19911787803
[post-traumatic ulcerated nodules of the ankle caused by mycobacterium smegmatis]. 19911789655
[synthesis and antimicrobial activity of substituted fluorobenzyl benzylidenethiazolidinediones and imidazolidinediones].the synthesis of six benzylidene thiazolidine-diones and three benzylidene imidazolidine-diones is described. in order to investigate their antimicrobial activity, they are evaluated against micro-organism such as staphylococcus aureus, streptococcus feacalis, mycobacterium smegmatis and neurospora crassa.19911795213
synthesis and the biological evaluation of the structural units of drummondin c.drummondin c (1) is an antibiotic isolated from a bioassay-directed fractionation of hypericum drummondii (grev. & hook.)t.&g. it showed significant activity against the gram-positive bacteria staphylococcus aureus and bacillus subtilis and the acid-fast bacterium mycobacterium smegmatis. two structural units of drummondin c, the 8-acetyl-5,7-dihydroxy-2,2-dimethylchromene (6) and 5-acetyl-3-methyl-filicinic acid (9), were synthesized to determine the relative importance of the two substructure ...19911798672
new antimicrobial filicinic acid derivatives from hypericum drummondii.bioactivity-guided fractionation of the hexane extract of the stems and leaves of hypericum drummondii has afforded four new filicinic acid derivatives: drummondin d, isodrummondin d, drummondin e, and drummondin f. the structures of these compounds were established by spectroscopic methods. all compounds possessed strong antibiotic activity against the gram-positive bacteria staphylococcus aureus and bacillus subtilis and the acid fast bacterium mycobacterium smegmatis.19911800634
genetic resistance/susceptibility to mycobacteria: phenotypic expression in bone marrow derived macrophage lines.congenic strains of mice susceptible (b10a.bcgs) or resistant (b10a.bcgr) to bcg were established. here we describe the model system which has been established to analyze the functional activities of macrophages in the two strains. we have immortalized bone marrow macrophages from b10a.bcgs and b10a.bcgr congenic strains of mice and derived cloned macrophage lines designated b10s and b10r, respectively. b10r and b10s cell lines exhibited surface markers and morphology typical of macrophages. b10 ...19911856597
the surgical management of superficial infections caused by atypical mycobacteria.we have recently treated four patients with atypical mycobacterial skin infections. two patients were infected with mycobacterium smegmatis after self-injection with a veterinary-grade anabolic steroid. to our knowledge, this complication has not been previously described. the other patients had steroid-dependent asthma and lower extremity infections involving m. kansasii and m. chelonei after minor household trauma developed. atypical mycobacterial skin infections may be seen as chronic ulcerat ...19911866699
citrate synthase from mycobacterium smegmatis. cloning, sequence determination and expression in escherichia coli.a mycobacterium smegmatis psti library was constructed by cloning these fragments downstream from the lac promoter of the expression vector phg171. three identically sized clones were isolated by complementation of an escherichia coli strain (chi 2338) deficient in citrate synthase. one insert (pbl265) was used in hybridization experiments with dna from e. coli and m. smegmatis and it was demonstrated that the clones were indeed from m. smegmatis. the transcription of the m. smegmatis citrate sy ...19911883331
site-specific integration of mycobacteriophage l5: integration-proficient vectors for mycobacterium smegmatis, mycobacterium tuberculosis, and bacille calmette-guérin.mycobacteriophage l5, a temperate phage of mycobacteria, integrates site-specifically into the mycobacterium smegmatis chromosome. we have identified the int gene and attp site of l5, characterized the chromosomal attachment site (attb), and constructed plasmid vectors that efficiently transform m. smegmatis through stable site-specific integration of the plasmid into the bacterial genome. these integration-proficient plasmids also efficiently transform slow-growing mycobacteria such as the path ...19911901654
isolation and expression of a gene cluster responsible for biosynthesis of the glycopeptidolipid antigens of mycobacterium avium.bacteria within the mycobacterium avium complex are prominent in the environment and are a source of serious disseminated infections in patients with aids. serovars of the m. avium complex are distinguished from all other mycobacteria and from one another by the presence of highly antigenic glycolipids, the glycopeptidolipids, on their surfaces. a genomic library of dna from serovar 2 of the m. avium complex was constructed in the escherichia coli-mycobacterium shuttle cosmid, pyub18, and used t ...19911938900
interaction of rifampicin with nonprotein thiols in mycobacterium smegmatis.in this study, the interaction of rifampicin (rif) with cellular glutathione (gsh) in mycobacterium smegmatis has been investigated. minimum inhibitory concentration of rif for m. smegmatis was demonstrated to be 17 micrograms ml-1 medium. three subinhibitory concentrations viz. 5, 10 and 15 micrograms rif ml-1 medium were used to study its interaction with cellular non protein thiols (npsh). maximum depletion (57.8%) in npsh levels [5, 5'-dithiobis (2-nitrobenzoic acid) assay] was observed on s ...19911953799
ethylenic mycolic acid biosynthesis: extension of the biosynthetic model using cell-free extracts of mycobacterium aurum and mycobacterium smegmatis.the hypothetical schemes proposed for the biosynthesis of unsaturated mycolic acids (r1-ch(oh)-ch(r2)-cooh) of mycobacteria cell walls were experimentally tested by using cell-free extracts either of mycobacterium aurum or of mycobacterium smegmatis which produce two kinds of unsaturated mycolic acids (mono and dialkene), [1-14c]acetate being the precursor. examination of specific radioactivities, in the presence or in the absence of isoniazid, an antituberculous drug inhibiting mycolic acid syn ...19911954242
calmodulin-like protein and the phospholipids of mycobacterium smegmatis.when mycobacterium smegmatis tmc1546 was grown at different concentrations of glucose supplemented to a synthetic medium already containing 2% v/v glycerol, the following changes were observed. amount of calmodulin-like protein (camlp), total and individual phospholipids (pls) namely phosphatidylethanolamine, cardiolipin, phosphatidylglycerol and phosphatidylinositol mannosides and total lipids and growth increased up to 5% w/v but decreased at higher concentrations of glucose (7.5% w/v and abov ...19911653167
transfer of plasmid rsf1010 by conjugation from escherichia coli to streptomyces lividans and mycobacterium smegmatis.the plasmid rsf1010 belongs to a class of plasmids (incq) that replicate in a range of bacterial hosts. although non-self-transmissible, it can be mobilized at high frequency between different gram-negative bacterial species if transfer functions are supplied in trans. we report the transfer of rsf1010 by conjugation from escherichia coli to the gram-positive actinomycetes streptomyces lividans and mycobacterium smegmatis. in its new hosts, the plasmid was stable with respect to structure and in ...19911657866
a novel transposon trap for mycobacteria: isolation and characterization of is1096.in the course of developing strategies to obtain a mutation in the aspartate semialdehyde dehydrogenase (asd) gene of mycobacterium smegmatis, an efficient transposon trap was constructed which may be generally useful for the identification of transposable elements in mycobacteria. a dna fragment containing the asd gene was replaced with an aminoglycoside phosphotransferase gene (aph) to generate a delta asd::aph allele. attempts to replace the wild-type asd gene with the delta asd::aph allele w ...19911660454
site-specific integration of the streptomyces plasmid psam2 in mycobacterium smegmatis.a method which allowed the stable integration of dna fragments at a single site (attb) in the chromosome of mycobacterium smegmatis was developed using an integrative element from streptomyces ambofaciens, psam2. vectors containing an escherichia coli replicon (pbr322), the kanamycin resistance gene from tn903 for selection in mycobacteria, and a fragment of psam2 containing the int gene as well as the attachment site (attp) were constructed and introduced to m. smegmatis by electroporation. tra ...19911665195
purification and characterization of dihydrofolate reductase from wild-type and trimethoprim-resistant mycobacterium smegmatis.dihydrofolate reductase (dhfr) from extracts of mycobacterium smegmatis strain mc2(6) and trimethoprim-resistant mutant mc2(26) was purified to homogeneity. in crude extracts, the specific activity of the enzyme from the trimethoprim resistant strain was comparable to that from the sensitive strain. the dhfr from both sources was purified using affinity chromatography on mtx-sepharose followed by mono q fplc. the enzyme has an apparent molecular mass of 23 kda from gel filtration on sephadex g-1 ...19912009922
[some observations on the mechanism of bactericidal activity of tween 80 on mycobacteria].in 0.1% tween 80 aqueous solution or in 0.1% tween 80-containing saline (0.9% nacl aqueous solution), mycobacterium smegmatis strain jucho bacteria were alive for 3 days, whereas, in 0.1% tween 80-containing phosphate buffer solution (ph 7.1), the bacteria died rapidly. since it was shown previously that m. smegmatis is one of the mycobacteria most susceptible to tween 80 (tsukamura, m.: kekkaku 63: 695-699, 1988), the 0.1% tween 80 aqueous solution or 0.1% tween 80-containing saline may be used ...19912023362
insertional mutagenesis and illegitimate recombination in mycobacteria.mycobacteria, particularly mycobacterium tuberculosis, mycobacterium leprae, and mycobacterium avium, are major pathogens of man. although insertional mutagenesis has been an invaluable genetic tool for analyzing the mechanisms of microbial pathogenesis, it has not yet been possible to apply it to the mycobacteria. to overcome intrinsic difficulties in directly manipulating the genetics of slow-growing mycobacteria, including m. tuberculosis and bacille calmette-guérin (bcg) vaccine strains, we ...19912052623
synthesis of some hydroxamic acid derivatives of benzimidazole and their antibacterial and antifungal activities.a number of 1h-benzimidazole-2-propanoic acid derivatives have been synthesized by phillips method, and their antibacterial and antifungal activities have been tested. the chemical structures of the synthesized compounds were elucidated by spectroscopic (ir, nmr, mass) and elementary analysis. investigation of antimicrobial activity of the compounds was done by agar dilution technique using bacteria (staphylococcus aureus atcc 25923, escherichia coli atcc 25922, pseudomonas aeruginosa atcc 27853 ...19921418079
cloning of mycobacterial histidine synthesis genes by complementation of a mycobacterium smegmatis auxotroph.histidine-requiring auxotrophs of mycobacterium smegmatis were isolated following n-methyl-n'-nitro-n-nitrosoguanidine treatment. one of these mutants, his5, was transformed with an m. smegmatis shuttle cosmid library, and complementing clones were isolated at a frequency of approximately 1%. a 2.3 kb fragment was subcloned and sequenced, and found to contain the start of an operon including the hisd gene and part of the hisc gene. no hisg gene was detected upstream of hisd, suggesting that the ...19921435262
some nutritional requirements of a mixed culture transforming reichstein's compound s into prednisolone.reichstein's compound s was successfully converted to prednisolone in a single-step fermentation using a mixed culture of curvularia lunata and mycobacterium smegmatis. introducing additional medium at the time of bacterial inoculation and increasing the m. smegmatis inoculum to 8% were necessary for maximal dehydrogenation of cortisol to prednisolone (86%). however, beef extract, corn-steep solids, and malt extract were inhibitory to the dehydrogenase activity and stimulatory to hydroxylase. of ...19921458367
[synthesis and structure of substituted bromo and nitrobenzyl benzylidene imidazolidinediones and thiazolidinediones].synthesis and physico-chemical properties of five bromobenzyl-benzylidene-imidazolidinediones and five nitrobenzyl- or benzyl-benzylidene-thiazolidinediones are described. the microbiological activity of bromobenzyl-benzylidene-imidazolidinediones against microorganisms such as candida albicans, neurospora crassa and mycobacterium smegmatis are evaluated.19921471825
further characterization of the histidine gene cluster of streptomyces coelicolor a3(2): nucleotide sequence and transcriptional analysis of hisd.we have further characterized the genomic region of streptomyces coelicolor a3(2) that contains genes involved in the biosynthesis of histidine. a 2,357-base pair fragment contained in plasmid psch3328 that complemented hisd mutations has been sequenced. computer analysis revealed an open reading frame that encodes a protein with significant homology to the escherichia coli, salmonella typhimurium and mycobacterium smegmatis hisd product, saccharomyces cerevisiae his4c, and neurospora crassa his ...19921488552
isolation and characterization of isoniazid-resistant mutants of mycobacterium smegmatis and m. aurum.inh-resistant mutants of mycobacterium aurum and m. smegmatis were isolated and characterized in an attempt to provide fresh insight into the activity of isoniazid (inh), a key antibiotic in the treatment of tuberculosis. in both cases, high levels of resistance were accompanied by slower growth rate, by loss of peroxidase and reduced catalase activities, although mycolic acid production was unaffected. a gene homologous to the katg gene of m. tuberculosis, encoding peroxidase-catalase, was dete ...19921488556
the catalase-peroxidase gene and isoniazid resistance of mycobacterium tuberculosis.tuberculosis is responsible for one in four of all avoidable adult deaths in developing countries. increased frequency and accelerated fatality of the disease among individuals infected with human immunodeficiency virus has raised worldwide concern that control programmes may be inadequate, and the emergence of multidrug-resistant strains of mycobacterium tuberculosis has resulted in several recent fatal outbreaks in the united states. isonicotinic acid hydrazide (isoniazid, inh) forms the core ...19921501713
molecular cloning and sequencing of the gene for mycocerosic acid synthase, a novel fatty acid elongating multifunctional enzyme, from mycobacterium tuberculosis var. bovis bacillus calmette-guerin.mycocerosyl lipids are found uniquely in the cell walls of pathogenic mycobacteria. mycocerosic acid synthase (mas) is a multifunctional protein which catalyzes elongation of n-fatty acyl-coa with methylamalonyl-coa as the elongating agent (rainwater, d. l., and kolattukudy, p. e. (1985) j. biol. chem. 260, 616-623). to understand how the various domains that catalyze the reactions involved in chain elongation are organized, mas gene from mycobacterium tuberculosis bovis bcg was cloned. a lambda ...19921527058
an escherichia coli-mycobacterium shuttle cosmid vector, pmsc1.a shuttle cosmid vector, pmsc1, has been constructed which replicates in escherichia coli and mycobacterium smegmatis. the vector was mainly derived from the lambda ori cosmid, lawrist4, and the mycobacterium fortuitum cryptic plasmid, pal5000, which replicates in m. smegmatis and mycobacterium bovis bcg. the vector contains two cos sites which facilitates library construction, unique bamhi and hindiii sites for cloning, and a kanamycin-resistance-encoding gene for selection in mycobacteria. aft ...19921531970
control of acyl-coa carboxylase activity in mycobacteria.acyl-coa carboxylase activity in four pathogenic mycobacteria and mycobacterium smegmatis was shown with both acetyl-coa and propionyl-coa substrates. only very low activity was detected in mycobacteria grown in host tissues or on egg-based media rich in lecithin and avidin. this appeared to be a result of severe depression of activity, as strains which could be grown both in host tissue and egg-based media, and in the relatively simple dubos or sauton's media showed 8 to 120-fold higher activit ...19921537546
cloning and expression of mycobacterium aurum carotenogenesis genes in mycobacterium smegmatis.this report describes the first successful transfer and complete expression of clustered mycobacterial genes controlling a biosynthetic pathway (carotenogenesis) in a homologous system. a genomic library of pigmented mycobacterium aurum a+ (yellow-orange) dna was constructed in shuttle vector phld-69. the colourless mutant a11 and the brick-red mutant ngr9 derived from m. aurum a+ were electroporated with the plasmid library. among the transformants, colonies different in colour from the recipie ...19921555758
identification of expression signals of the mycobacteriophages bxb1, l1 and tm4 using the escherichia-mycobacterium shuttle plasmids pyub75 and pyub76 designed to create translational fusions to the lacz gene.mycobacterial expression signals were cloned using specially constructed gene fusion shuttle plasmid probes carrying a truncated escherichia coli lacz (beta-galactosidase) gene which lacked a promoter, a ribosome binding site, and an atg start codon. libraries of mycobacteriophage bxb1, l1 and tm4 dnas were constructed, and introduced by electroporation into mycobacterium smegmatis and the 'bacille calmette-guérin' (bcg). clones carrying mycobacterial expression sequences were detected by their ...19921556552
genetic and biochemical analysis of ribosomal proteins of minocycline-susceptible and -resistant mycobacterium smegmatis.a minocycline (mino)-resistant mutant was isolated from mycobacterium smegmatis strain rabinowitschi. polypeptide synthesis in the cell-free system prepared from the mutant was resistant to minocycline (mino) because of alterated 30s ribosomal subunits. upon two-dimensional gel electrophoresis, two proteins of 30s subunit were found to be altered. mino resistance phenotype was transferred by mating to the recipient strain p-53. mino resistance phenotype of a recombinant thus obtained was transfe ...19921584079
[synthesis and antimicrobial activity of chlorobenzyl benzylidene imidazolidinedione derivatives and substituted thiazolidinediones].the synthesis of five chlorobenzyl benzylidene imidazolidinediones and four fluorobenzyl benzylidene thiazolidinediones is described. in order to investigate their antimicrobial activity they are evaluated against microorganism such as candida albicans, neurospora crassa, staphylococcus aureus, mycobacterium smegmatis and escherichia coli.19921615023
purification and partial characterization of a penicillin-binding protein from mycobacterium smegmatis.penicillin-binding proteins (pbps), although characterized from several organisms, have so far not been studied in mycobacteria. the present study is the first characterization of a pbp from mycobacterium smegmatis. the pbp was purified by solubilization of the membranes with triton x-100 and successive chromatography of the solubilized proteins on ampicillin-linked ch sepharose 4b and de-52. the purified pbp (m(r), 49,500) catalyzed a model transpeptidase reaction with the tripeptide acetyl2-l- ...19921624470
the ability of bacteria to synthesize a new cyclopyrophosphate correlates with their tolerance to redox-cycling drugs: on a crossroad of chemotherapy, environmental toxicology and immunobiochemical problems.many redox-cyclers were recently shown to induce, in some bacterial species, large-scale biosynthesis of a new 2-methylbutan-1,2,3,4-tetraol-2,4-cyclopyrophosphate believed to be involved in anti-stress reactions. in the present study mycobacterium smegmatis, micrococcus luteus and brevibacterium ammoniagenes were shown to begin synthesis of the new cyclopyrophosphate when cultivated in a medium containing furacilin or furadonin (widely used nitrofuran antibacterial drugs) and to maintain close ...19921292477
isolation and analysis of is6120, a new insertion sequence from mycobacterium smegmatis.insertion sequence is6120 from mycobacterium smegmatis was identified by its ability to transpose into different sites in the lambda repressor gene, cl857, carried on an escherichia coli/mycobacteria shuttle plasmid. is6120 is a novel 1.5 kb insertion sequence, which has 24-bp imperfect terminal inverted repeats and generates 9-bp duplications of the target dna following insertion. is6120 is present in at least three copies in m. smegmatis but was not found in other species, including mycobacter ...19921310791
correlation between calmodulin-like protein, phospholipids, and growth in glucose-grown mycobacterium phlei.in mycobacterium phlei tmc 1548 supplementation of growth medium containing 2% v/v glycerol with glucose (up to 5% w/v) resulted in an increase in growth (yield of cells), in amount of total phospholipids, and in each of the individual phospholipids (cardiolipin, phosphatidylethanolamine, phosphatidylinositol and its mannosides, and phosphatidylglycerol). however, when the medium was supplemented with a higher concentration (7.5% w/v) of glucose, both growth and phospholipid levels decreased to ...19921319278
insertion into the mycobacterium smegmatis genome of the aph gene through lysogenization with the temperate mycobacteriophage ms6.a derivative of the temperate mycobacteriophage ms6 containing the aph gene from transposon tn5 was constructed. in the transductants the aph gene was integrated in the bacterial genome. the aph gene is stably maintained in the absence of positive selection after more than 150 generations. the results presented in this report show that ms6 can be used as a vehicle for the integration of foreign dna into the mycobacterium smegmatis genome.19921325383
treatment of opportunistic mycobacterial infections with enrofloxacin in cats.marked improvement was observed in the condition of 6 cats with opportunistic mycobacterial infections during treatment with enrofloxacin, a fluoroquinolone antibiotic. complete remission was achieved in 3 cats after 3 to 7 weeks of treatment. the other 3 cats were euthanatized after 1 to 2 weeks of treatment for reasons not related to the treatment. lesions did not recur within the follow-up period, which ranged from 9 to 16 months. treatment of opportunistic mycobacterial infection in cats is ...19921331001
a stable escherichia coli-mycobacterium smegmatis plasmid shuttle vector containing the mycobacteriophage d29 origin.a plasmid shuttle vector for escherichia coli and mycobacteria was constructed from an e. coli plasmid containing the cole1 origin, a 2.6-kb psti fragment from bacteriophage d29 that grows in numerous mycobacterial species, and the kanamycin resistance gene either of tn903 or of tn5. the resultant plasmid is 7.63 kb and can be introduced via transformation into mycobacterium smegmatis with high efficiency. in m. smegmatis the plasmid is stable and apparently present in multiple copies. biolumine ...19921334270
expression of escherichia coli beta-galactosidase in mycobacterium bovis bcg using an expression system isolated from mycobacterium paratuberculosis which induced humoral and cellular immune responses.a promoter sequence, pan, was isolated from mycobacterium paratuberculosis and characterized. this promoter lies adjacent to, and outside, the 3' end of an is900 insertion element. is900 contains an open reading frame, orf2, on the complementary strand which codes for the putative transposase of this insertion sequence. a dna fragment containing pan and part of orf2 was fused to the lacz gene and inserted into the replicative shuttle vector prr3. mycobacterium smegmatis and mycobacterium bovis b ...19921336563
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