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Brik H - - 1976
Mild acid treatment of natamycin (IV) results in biologically inactive aponatamycin (VI), an amphoteric substance with some natamycin-like chemical and physical properties. Aponatamycin contains one natamycin- and one natamycinolide-moiety. More drastic acid degradation of natamycin eliminates the aminosugar under formation of the dimer (VII) of the hypothetical aglycone of natamycin, ...
Garvin A J - - 1976
A method is described whereby a Feulgen type of hydrolysis of deoxyribonucleic acid is carried out on paraffin sections of routinely fixed tissues by controlled exposure of the sections to Bouin's fluid. Subsequent staining with Schiff reagent followed by methylene blue distinguishes red-to purple-stained deoxyribonucleic acid from blue-stained ribonucleic acid. ...
White T G - - 1976
Fourteen strains of Erysipelothrix rhusiopathiae, representing extremes of host-range and world distribution, were examined for: 1) protein composition as determined by electrophoresis and electrofocus patterns, 2) guanine-cytosine mole ratios of their respective deoxyribonucleic acids, and 3) carbohydrate fermentation patterns. No correlation is apparent between any particular physical-chemical property and virulence ...
Bennett P M - - 1976
A number of well-characterized R plasmids (R1drd 19. K1.R100-1, R46, R55-1, R64-11, R388, and R751) will mobilize an integrated amp gene from the chromosome of Escherichia coli K-12. R391 will not act in this way. The process involves recombination, and in each case the mobilizing plasmid acquires an additional piece ...
Dworsky P - - 1976
Nuclear bodies were isolated from Escherichia coli spheroplasts by two different lysis procedures. Their lipid and protein content and the superhelix density was measured. The preparations differed mainly in respect to the amount of the attached membrane material, which seems to be an essential factor in maintaining the stability of ...
Bradley D W - - 1976
Two distinct deoxyribonucleic acid polymerase activities were found associated with liver fractions containing Dane particles and Dane cores.
Klaenhammer T R - - 1976
Two defective transducing bacteriophages induced by exposure of Streptococcus lactis C2 to ultraviolet irradiation have been isolated and characterized. These temperate phages designated c2t1 and c2t2 were isolated by cesium chloride equilibrium density gradient centrifugation of phage preparations concentrated by polyethylene glycol precipitation. The equilibrium gradient contained two visually apparent ...
Levinson W - - 1976
The infectivity of intact lambda phage and transfection by lambda deoxyribonucleic acid were inactivated by exposure to the copper complexes of N-methyl-isatin beta-thiosemicarbazone, thiosemicarbazide, and semicarbazide, but not methyl-isatin. No inactivation was observed when these compounds were used in the absence of copper sulfate. This confirms our previous observation that ...
Duijndam W A - - 1975
Theoretical considerations on the expected kinetics of the course of the Feulgen-Schiff reaction show that the leveling off of the first part of the Feulgen hydrolysis curve can be explained by the gradual conversion of deoxyribonucleic acid (DNA) to apurinic acid (APA). In addition, depolymerization of DNA caused by the ...
Miyagawa T - - 1975
The capability of guinea pig epidermal extracts to hydrolyze deoxyribonucleic acid has been studied. The results of investigation by gel filtration on Sephadex G-75 column and by viscometry on the mode of hydrolysis of deoxyribonucleic acid by epidermal extracts revealed that deoxyribonucleic acid was degraded by both endonuclease and exonuclease ...
Zaritsky A - - 1975
The degree to which the rate of deoxyribonucleic acid synthesis in thy- cultures of Escherichia coli is stimulated after a period of thymine starvation is shown to be a function of the concentration of thymine present as well as of the culture doubling time. Inhibition of deoxyribonucleic acid synthesis by ...
Yoakum G H - - 1975
Long-wavelength ultraviolet light (300 to 400 nm) converts L-tryptophan to a photoproduct that is toxic for bacterial cells in dark conditions. We now report that similar photoproducts of l-tryptophan sensitize bacterial deoxyribonucleic acid to 365-nm radiation, increasing the yield of deoxyribonucleic acid strand breaks (or alkali-labile bonds) by approximately 11.5-fold. ...
Joenje H - - 1975
Competent cultures of Bacillus subtilis 168 have been fractionated into a high-competent and a low-competent fraction by a large-scale separation technique. Membrane vesicles isolated from both cell fractions are equally active in the transport of L-glutamate. Both membrane vesicle preparations seem to have similar endo- and exonuclease activities. Also, both ...
Nair C K - - 1975
Single-strand breaks in deoxyribonucleic acid of Escherichia coli B/r cells exposed to 20 krads of gamma radiation could be rejoined by incubation of irradiated cells in growth medium. In the presence of 0.25% phenethyl alcohol, this repair was completely inhibited although deoxyribonucleic acid and protein syntheses were suppressed only partially.
Hanna M H - - 1975
The dnaA and dnaC genes are thought to code for two proteins required for the initiation of chromosomal deoxyribonucleic acid replication in Escherichia coli. When a strain carrying a mutation in either of these genes is shifted from a permissive to a restrictive temperature, chromosome replication ceases after a period ...
DiJoseph C G - - 1974
The deoxyribonucleic acid of the thermosensitive R factor, Rts1, has been examined by the technique of sedimentation in alkaline sucrose, electron microscopy, and radiation target size. All these methods yielded a molecular weight of approximately 120 million for Rts1 deoxyribonucleic acid in Escherichia coli. Sedimentation analysis revealed that Rts1 deoxyribonucleic ...
Tärnvik A - - 1974
Human lymphocytes were stimulated in vitro by phytohemagglutinin, concanavalin A, pokeweed mitogen, purified protein derivative-tuberculin, and allogenic cells. The deoxyribonucleic acid synthesis of the lymphocytes was inhibited in increasing degree by 4 to 8 mug of amphotericin B per ml of culture irrespective of lymphocyte stimulant used. The effect of ...
Niveleau A - - 1974
The attachment of deoxyribonucleic acid to the membrane in Escherichia coli 15 T(-) cells incubated with [(3)H]thymidine was studied by electron microscopy. Isolated deoxyribonucleic acid-membrane complexes were prepared from synchronized and unsynchronized cells during the exponential or stationary phase of growth and were examined by autoradiography. After short pulses with ...
Louarn J - - 1974
The origin of replication in Escherichia coli K-12 was mapped by determining the rate of marker replication during a synchronous round of replication. Four isogenic strains were made lysogenic for lambdaind(-) and for phage Mu-1, with Mu-1 integrated into a different chromosomal location in each strain. Cultures were starved for ...
Kupersztoch-Portnoy Y M - - 1974
The presence of supercoiled deoxyribonucleic acid in the form of a relaxation complex is described for the antibiotic resistance plasmids R64, R28K, and R6K. The properties of these relaxation complexes indicate that they consist of a covalently closed circular deoxyribonucleic acid molecule associated with an activable, single strand-specific endonuclease.
Maniloff J - - 1974
A Mycoplasma gallisepticum subcellular fraction (P2), which contains the deoxyribonucleic acid replication complex, can be isolated by differential centrifugation of freeze-thaw-lysed cells. The nascent deoxyribonucleic acid is released from P2 by Lubrol-WX, sodium dodecyl sulfate, Pronase, and deoxyribonuclease, but not by saponin, ribonuclease, phospholipase C, or high-frequency sonic treatment. Sonic ...
Moss S H - - 1974
Investigation of the effect of photoreactivation, excision, and recombination repair, individually and in combination, on the survival of ultraviolet-irradiated Escherichia coli K-12 mutants has led to a possible explanation of the loss of photoreactivability and of the complex changes in viability observed during liquid-holding. It is suggested that at higher ...
Mayer L W - - 1974
Five of six independent gonococcal isolates have been found to harbor a plasmid pool of covalently closed-circular deoxyribonucleic acid about 2.4 x 10(6) daltons in size. The plasmid species were 0.5-mol fraction of guanine plus cytosine and comprised 6 to 8% of the total gonococcal deoxyribonucleic acid equivalent, to approximately ...
Deutch C E - - 1974
To clarify the relationship between thymineless death and thymineless mutagenesis, the induction of arginine revertants of Escherichia coli TAU-bar by thymine starvation was examined in physiological terms. Induced revertants were detectable both on minimal medium lacking arginine and minimal medium supplemented with 1 mug of arginine per ml. Substantial thymineless ...
Campbell J L - - 1974
Direct assay for deoxyribonucleic acid polymerase II in extracts has been used to screen recombinants for the polB allele in Hfr x F(-) crosses, F-ductants in episome transfer, and transductants in generalized transduction by phage P1. The polB gene is located at 2 min on the Escherichia coli linkage map; ...
Inselburg J - - 1974
Cells colicinogenic for the colicin plasmids E1 or E2 (Col E1 and Col E2, respectively) were selected for a loss of colicin production after infection with bacteriophage Mu. Extrachromosomal deoxyribonucleic acid that was larger than the original colicin plasmids was found in such cells. A small insertion mutant in Col ...
Hopper A K - - 1974
The time course of synthesis and breakdown of various macromolecules has been compared for sporulating (a/alpha) and nonsporulating (a/a and alpha/alpha) yeast cells transferred to potassium acetate sporulation medium. Both types of cells incorporate label into ribonucleic acid and protein. The gel electrophoresis patterns of proteins synthesized in sporulation medium ...
Hang Y D - - 1974
Geotrichum candidum completely neutralized the acid brine and reduced its biochemical oxygen demand (BOD) by 88%. Yield of dry mycelium was 62 g per 100 g of BOD utilized.
Durkacz B W - - 1974
Induction of colicins E1 and E2 in Escherichia coli occurs when plasmid synthesis has been inhibited either by nalidixic acid or by lack of deoxyribonucleic acid polymerase I. Moreover, colicin E1 and E2 synthesis induced by mitomycin C and exposure to chloramphenicol is not associated with a large increase in ...
Leech R W - - 1974
Within the developing nervous system, there is a complex relationship between the accumulation of sudanophilic lipids in glial cells and gestational and postnatal age. Sudanophilic lipids accumulate to a small degree as a stage of normal premyelin lipogenesis, but large amounts of such accumulations may be considered abnormal. The dividing ...
Kahn P L - - 1973
Plasmid deoxyribonucleic acid from Escherichia coli harboring either the V colicinogenic factor (Col V) or the derivative fertility factor (Fv), (a non-colicin-producing fertility factor derived from Col V) were separated by cesium chloride-ethidium bromide centrifugation and examined by electron microscopy. Results indicate a deletion of 11 mum of deoxyribonucleic acid ...
Weiner R M - - 1973
The relationship between chromosome replication and morphogenesis in the budding bacterium Hyphomicrobium neptunium has been investigated. Nalidixic acid was found to completely inhibit deoxyribonucleic acid synthesis, but not ribonucleic acid synthesis. The antibiotic was bacteriostatic to the organism for the initial 5 h of exposure; thereafter it was bacteriocidal. Observation ...
Stewart C R - - 1973
When bacteriophage SP02 infects a Bacillus subtilis culture during or shortly after transformation, the frequency of transformants among the resulting lysogens is greatly reduced relative to that in the uninfected culture. The effect can occur after the deoxyribonucleic acid has been taken up and covalently attached to recipient deoxyribonucleic acid.
Rosenkranz H S - - 1973
Hydroxyurea, a potent inhibitor of deoxyribonucleic acid synthesis, inhibits the development of trachoma agent when applied at a concentration of 5 x 10(-2) M. At a lower concentration, 5 x 10(-4) M, hydroxyurea permits the development of the trachoma inclusion bodies and initial bodies, but arrests the formation of elementary ...
Michaels C A - - 1973
The effect of the antibiotic nalidixic acid on macromolecular metabolism in the yeast Saccharomyces cerevisiae has been studied. It was found that, upon the addition of nalidixic acid to a logarithmically growing culture, there is a transient inhibition of total cell ribonucleic acid, deoxyribonucleic acid, and protein synthesis, after which ...
Pemberton J M - - 1973
Using a variety of techniques, it has been established that the sex factor FP2 has a density of 1.717 g/cm(3) (corresponding to a guanine plus cytosine [G + C] content of 58%) and a mean circular contour length of 28.5 +/- 0.6 mum (corresponding to a molecular weight of 59 ...
Brunovskis I - - 1973
Electron microscopy examination of phiII-H deoxyribonucleic acid heteroduplexes, together with polyacrylamide gel electrophoretic analyses of phage ribonucleic acid species and proteins labeled in phiII or H-infected cells, demonstrates that Pasteurella pestis phage H is nearly identical to coliphage phiII.
George D - - 1972
Ultraviolet irradiation of Escherichia coli polA(-) cells reduces their capacity to support the growth of T4 phage. There is no additional loss of capacity observed in pol tsA(-)recA(-) double mutants at the nonpermissive temperature. The reversion frequency of a T4 rII mutant after ultraviolet irradiation is not changed by the ...
Lee H H - - 1972
A proteinaceous substance was detected in the liver of several animal species that inhibited the multiplication of certain deoxyribonucleic acid, but not ribonucleic acid, viruses. Preliminary experiments suggested that its site of action was not extracellular. It did not inhibit virus by interfering with adsorption to cells. It was suggested ...
Ballesta J P - - 1972
By using the M-band technique we have shown that portions of the membranes of Bacillus megaterium and Escherichia coli vary in their affinity for magnesium-Sarkosyl crystals and in phospholipid composition. The portion to which deoxyribonucleic acid is attached comprises as little as 4% of the total cell membrane, has a ...
Ou J T - - 1972
By means of both electron microscopy and plaque assay techniques, 10(-3)m Zn(2+) has been shown to reduce the adsorption rate of male-specific filamentous deoxyribonucleic acid bacteriophages to the tips of F pili. In contrast, 10(-3)m Zn(2+) did not affect the adsorption of male-specific ribonucleic acid phages to the sides of ...
Messer W - - 1972
Three processes necessary for the initiation of deoxyribonucleic acid replication have been separated in time in synchronously growing Escherichia coli B/r. One can be inhibited with 2 mug of chloramphenicol per ml and occurs about 20 min prior to initiation. A second step, occurring 5 to 10 min prior to ...
Lee L F - - 1972
Leukocytes recovered from birds inoculated with an oncogenic strain of Marek's disease virus synthesized deoxyribonucleic acid in vitro at a rate 7.9 times that of leukocytes from normal birds or birds inoculated with the nononcogenic herpesvirus of turkeys. A close relationship was observed between the level of in vitro deoxyribonucleic ...
Lin F H - - 1972
Maedi virus contains a ribonucleic acid (RNA) which can be resolved into three major components, namely, 62S, 33S, and 13S, by sucrose gradient centrifugation. The presence of RNA- and deoxyribonucleic acid (DNA)-dependent DNA polymerase in virions of maedi virus was demonstrated. The enzyme product could be converted into acid-soluble form ...
Martini A - - 1972
The deoxyribonucleic acid base composition (percent guanine + cytosine [GC]) was determined for 29 strains, representing 18 species of the genus Kluyveromyces. It was concluded that on the basis of GC content (47.4%) and other properties K. veronae occupies an uncertain position in the genus Kluyveromyces. The GC content of ...
Dubnau D - - 1972
A series of sheared donor-recipient complex samples were prepared from a competent Bacillus subtilis culture which had been transformed by using (3)H, (2)H-labeled deoxyribonucleic acid. Measurement of the molecular weights and buoyant densities of these samples led to the following conclusions. (i) The average size of the single-stranded donor segment ...
Knovicka J - - 1972
Long-tailed azotophages of two different serological groups have deoxyribonucleic acid species whose densities correspond to a molar percentage of guanine plus cytosine of 52 to 53. Similar measurements on the short-tailed phages gave values of 56 to 57 moles percent. The azotophages include representatives of the three morphological types classified ...
LaMontagne J R - - 1972
Bacteriophage TSP-1 was isolated from soil in a search for phage which would form plaques on Bacillus subtilis W168 at 53 C. It forms clear plaques only at temperatures from 50 to 55 C. Approximately 95% of the free phage adsorb after 2 min at 53 C. The lytic cycle ...
Skyring G W - - 1972
Guanine plus cytosine (GC) contents of the deoxyribonucleic acids of Desulfovibrio and Desulfotomaculum have been used as a basis for classification. Some of these data have been incorrectly calculated, resulting in errors of as much as 5% GC. This situation has been corrected by a reanalysis of existing data and ...
Rana R S - - 1972
When heat-activated spores of Bacillus cereus T (thy(-)) were germinated and grown in medium containing (3)H-thymidine, a significant amount of radioactivity was incorporated into ribonucleic acid and deoxyribonucleic acid (DNA). A method was developed to restrict the incorporation of radioactivity from (3)H-thymidine into DNA only. This was accomplished by labeling ...
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