bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth and Division of Protoplasts of
Bacillus megaterium
and Inhibition of Division by Penicillin
Authors: Kusaka Iwao
Published: January 2020

Protoplasts of
Bacillus megaterium
grew well and divided in nutrient broth containing 0.5
m
NaCl as the stabilizer. Protoplasts also grew when sucrose or succinate was used instead of NaCl; however, no division phenomena were observed. The sequence of growth and division was similar to the results obtained by McQuillen. Protoplasts enlarged from 1.8 to 3.5 μ in diameter, and then a small protuberance formed in the enlarged cells. The nodules enlarged until eventually symmetrical dumbbell-shaped bodies were formed, which then separated into two daughter protoplasts having a diameter of about 2.5 μ. Deoxyribonucleic acid and ribonucleic acid were halved during division. Penicillin inhibited the division of protoplasts, though the growth was not influenced by the drug. Membrane-bound amino sugar content was considerably reduced when the cells were grown in the presence of penicillin. These results suggest that organized murein formed on the protoplasts membrane may play an important role in the septation process.
Experimental Salmonellosis XI. Induction of Cellular Immunity and Formation of Antibody by Transfer Agent of Mouse Mononuclear Phagocytes
Authors: Mitsuhashi Susumu , Saito Kazuko , Osawa Nobutaka , Kurashige Satonori
Published: January 2020

When mice were injected intraperitoneally with a ribonucleic acid (RNA) preparation extracted from the peritoneal mononuclear phagocytes (termed monocytes) of immunized mice, these macrophages developed cellular immunity and cellular antibodies. The peritoneal monocytes were obtained from normal mice and maintained in tissue culture bottles in a homogeneous cell population. When they were treated in vitro with an immune RNA preparation, they acquired cellular immunity, and cellular antibodies were detectable in such monocytes. These results suggest that the mononuclear phagocytic cell line constitutes a cell line responsible for antibody formation.
Factors Affecting the Antigenicity of
Trichophyton rubrum
Authors: Stuka Andrew J. , Burrell Robert
Published: January 2020

Nitrogen determinations, performed upon the mycelia of
Trichophyton rubrum
, indicated that both the total nitrogen to mycelial weight ratio and the protein nitrogen to mycelial weight ratio decreased as the age of the mycelia increased. An increase in nitrogen concentration in the medium produced an increase in the total nitrogen to mycelia weight ratio, but did not necessarily increase the protein nitrogen to mycelial weight ratio. The optimal nitrogen source concentration which produced the highest protein nitrogen to mycelium ratio was found to be considerably less than that recommended in most standard Sabouraud medium formulations. Antisera to antigen preparations, grown on low concentrations of Multipeptone, produced more lines in the gel diffusion reaction than did antisera to antigens grown on standard concentrations of Multipeptone. Antisera to antigenic preparations from 2-week-old mycelia exhibited better and sometimes more lines than those of antigens prepared from 1- or 3-week-old mycelia, regardless of the nitrogen concentration in the medium. Dialysis and storage of the antigen produced no change in the quality of the precipitin lines, even though both processes involved considerable loss of Lowry protein. Immunofluorescence studies showed that young mycelia were more antigenic than the old mycelia, since a substantial degree of cell wall fluorescence was exhibited by the young mycelia, especially at the hyphal tips. Older mycelia lacked this fluorescence. An extracellular antigen was also found to be associated with the young mycelia, but cytoplasmic fluorescence was not observed.
Resistance of Vaccinated Mice to Typical and Atypical Strains ofCoccidioides immitis
Authors: Huppert M. , Levine H. B. , Sun S. H. , Peterson E. T.
Published: January 2020

In earlier reports, it was shown that mice and monkeys could be immunized against otherwise lethal challenge doses ofCoccidioides immitisarthrospores. The vaccine was composed of Formalin-killed, in vitro grown, endosporulating spherules ofC. immitisstrain Silveira. In this study, mice were immunized as in the earlier work and then challenged intranasally with arthrospores from seven heterologous strains ofC. immitis. Two of these strains were typical of the species, and five were atypical with respect to their cultural characteristics and morphology of microscopic structures. The vaccinated animals were well protected against challenge doses that were lethal to a majority of the control animals, regardless of the strain of fungus employed. The infection ratios among surviving vaccinated and control animals were comparable, but demonstrable lesions were generally smaller and less numerous in the vaccinated groups. It is suggested that these strains are at least immunogenically similar, although not necessarily identical, and that a vaccine prepared from a single strain ofC. immitiswould be practical for an immunization program.
Experimental Study of the Pathogenicity of Aspergilli for Mice
Authors: Ford Scott , Friedman Lorraine
Published: January 2020

The relative virulence was determined for 14 species of aspergilli, by inoculating normal mice intravenously with graded doses of spores. Eleven were found to possess some degree of virulence, whereas three others were avirulent. Members of the
Aspergillus flavus
group were the only species that consistently killed mice with doses as low as 10
4
viable spores. When the in vivo fate of spores was compared for a virulent and an avirulent strain of
Aspergillus
, spores of the latter were cleared rapidly from the liver and spleen but grew in the kidneys and brain, producing progressive disease. Mice which inhaled spores did not succumb, but macrophages washed from their lungs contained spores. A relationship of virulence to spore characteristics such as germination time, size, shape, and external markings could not be established. Virulence could not be related to aflatoxin production inasmuch as at least one virulent strain did not produce aflatoxin in vitro.
Lysis of
Escherichia coli
by Ethylenediaminetetraacetate and Phospholipases as Measured by β-Galactosidase Activity
Authors: Slein Milton W. , Logan Gerald F.
Published: January 2020

A permeaseless mutant of
Escherichia coli
, which produces β-galactosidase constitutively, was treated briefly with ethylenediaminetetraacetate and then with the phospholipases of
Bacillus cereus
. Cell lysis occurred, as indicated by an increase in β-galactosidase activity and a decrease in absorbancy of the cell suspension. The susceptibility of the cells to attack by ethylenediaminetetraacetate and the phospholipases was markedly affected by the age of the cells when harvested. The results suggest that permeability changes may be associated with the activity of a phospholipase that specifically degrades phosphatidyl ethanolamine. A sonic-treatment method for determining the total β-galactosidase content of
E. coli
cells, which is independent of their age when harvested, is described.
Biosynthesis of Streptococcal Cell Walls:
N
-Acetyl-
d
-Muramic Acid
Authors: Barkulis S. S. , Boltralik J. J. , Hankin H. , Heymann H.
Published: January 2020

Glucose-
1
-
14
C
and acetylglucosamine-
1
-
14
C
were added singly and together with equal amounts of the unlabeled reciprocal to Brain Heart Infusion and used for the culture of
Streptococcus pyogenes
. The labeling pattern of the rhamnose, glucosamine, and muramic acid in the cell wall supported an intermediary role for acetylglucosamine in providing the C1-C6 moiety of muramic acid. Although radioactivity in the C2-C9 portion of muramic acid suggested that some of the lactyl group (C7-C9) came from glycolytic products, there was also considerable contribution to it from noncarbohydrate sources. Using cell-free extracts, we were unable to demonstrate biosynthesis of acetylmuramic acid, either free or nucleotide-bound, while glycolysis was occurring. The formation of uridine diphosphoacetylmuramic acid has been reported by others who used uridine diphospho-
N
-acetyl-
d
-glucosamine, phosphoenolpyruvate, reduced nicotinamide adenine dinucleotide, and reduced nicotinamide adenine dinucleotide phosphate. However, we did not detect the formation of this compound.
Role of
S
-Adenosylmethionine in Methionine Biosynthesis in Yeast
Authors: Botsford J. L. , Parks L. W.
Published: January 2020

Extracts of
Saccharomyces cerevisiae
were used to develop a cell-free system capable of converting the β-carbon of serine into the methyl group of methionine. No requirement for either
S
-adenosylmethionine or
S
-adenosylhomocysteine could be demonstrated for net methionine biosynthesis. Growth of the cells in B
12
did not affect the reaction. The mechanism for the methylation of homocysteine in yeast appears to be similar to the non-B
12
system in
Escherichia coli
.
Biochemical Basis of Obligate Autotrophy in Blue-Green Algae and Thiobacilli
Authors: Smith Arnold J. , London Jack , Stanier Roger Y.
Published: January 2020

Differential rates of incorporation of sugars, organic acids, and amino acids during autotrophic growth of several blue-green algae and thiobacilli have been determined. In obligate autotrophs (both blue-green algae and thiobacilli), exogenously furnished organic compounds make a very small contribution to cellular carbon; acetate, the most readily incorporated compound of those studied, contributes about 10% of newly synthesized cellular carbon. In
Thiobacillus intermedius
, a facultative chemoautotroph, acetate contributes over 40% of newly synthesized cellular carbon, and succinate and glutamate almost 90%. In the obligate autotrophs, carbon from pyruvate, acetate, and glutamate is incorporated into restricted groups of cellular amino acids, and the patterns of incorporation in all five organisms are essentially identical. These patterns suggest that the tricarboxylic acid cycle is blocked at the level of α-ketoglutarate oxidation. Enzymatic analyses confirmed the absence of α-ketoglutarate dehydrogenase in the obligate autotrophs, and also revealed that they lacked reduced nicotinamide adenine dinucleotide oxidase, and had extremely low levels of malic and succinic dehydrogenase. These enzymatic deficiencies were not manifested by the two facultative chemoautotrophs examined. On the basis of the data obtained, an interpretation of obligate autotrophy in both physiological and evolutionary terms has been developed.
Pyruvate Metabolism in
Sarcina maxima
Authors: Kupfer Dorothy G. , Canale-Parola E.
Published: January 2020

The mechanisms of pyruvate cleavage and hydrogen production by
Sarcina maxima
were studied. It was found that a phosphoroclastic system for pyruvate oxidation, similar to that occurring in saccharolytic clostridia, is present in
S. maxima
. Cleavage of pyruvate by extracts of the latter organism resulted in the formation of acetyl phosphate, CO
2
, and electrons which were transferred to ferredoxin. Formate was not an intermediate in this system. Pyruvate oxidation was coupled with ferredoxin-dependent nicotinamide adenine dinucleotide phosphate (NADP) reduction. A hydrogenase, active in particulate extracts of
S. maxima
, did not accept electrons from reduced ferredoxin. Formate was detected as a fermentation product when
S. maxima
was grown in media buffered with CaCO
3
. Whole cells and extracts degraded formate to H
2
and CO
2
. The evidence suggests that electrons generated by ferredoxin-linked pyruvate oxidation by
S. maxima
are not used for H
2
production, but that they serve for the reduction of NADP. Reduced NADP may be utilized by the organisms for synthesis of cell material. Production of H
2
by
S. maxima
may occur through a pyruvate clastic system similar to that present in coliform bacteria.
Energy Supply and Cell Yield in Aerobically Grown Microorganisms
Authors: Hernandez Eovaldo , Johnson Marvin J.
Published: January 2020

Cell yields of
Pseudomonas fluorescens, Aerobacter cloacae
UW-C83,
Escherichia coli
K-12,
Candida utilis
UW-3, and
Saccharomyces carlsbergensis
UW-110 grown aerobically on several carbon sources are reported. The Y

atp

concept is discussed in relation to the yields on oxygen and to assumed P to O ratios for bacteria and reported P to O ratios for yeast.
Identification of
Actinomyces israelii
and
Actinomyces naeslundii
by Fluorescent-Antibody and Agar-Gel Diffusion Techniques
Authors: Lambert Frank W. , Brown June M. , Georg Lucille K.
Published: January 2020

This study was an attempt to develop a fluorescent-antibody (FA) test to differentiate
Actinomyces israelii
and
A. naeslundii
as an aid in their laboratory identification. Two strains of
A. israelii
(X522 and A601) and two strains of
A. naeslundii
(X454 and X600), which had received intensive study by several investigators, were used for the immunization of rabbits. Working titers, based on tests with antigens prepared from the homologous strains and from well-established heterologous strains, were determined for each labeled antibody preparation. These conjugates and their normal serum control conjugates were used separately to stain 85 cultures of
Actinomyes
species and 23 strains of other species that might be confused with them. Acetone-precipitated soluble antigens from these same strains were tested with different antisera in the agar-gel diffusion test. Results showed that
A. israelii
(X522 and A601) and
A. naeslundii
(X454 and X600) labeled antiglobulins, when used at their working titers, stained most strains of their homologous species. Agar-gel diffusion results showed general agreement with those of the FA tests. The two tests appear to be equal in sensitivity, but the FA test is more specific, since several cross-reactions were noted with the agar-gel diffusion test whereas no cross-reactions were obtained with the FA reagents. Agar-gel and FA studies suggest that at least two serotypes of
A. israelii
may be associated with human disease. Although the majority of strains tested in this study appear to belong to a common serotype, “serotype 1,” two strains of an apparent second serotype, “serotype 2,” were encountered. FA staining of tissue impression smears from experimentally infected mice was successful when a counterstain, Evans Blue dye, was used.
Media for the Enhancement of Fluorescent Pigment Production by
Pseudomonas
Species
Authors: Garibaldi J. A.
Published: January 2020

By a simple modification, common commercial dehydrated laboratory media can be used for the evaluation of fluorescent pigment excretion by
Pseudomonas
species. The addition of sufficient sterile egg white or of the iron-binding egg white protein, conalbumin, to bind all the iron in these media converted them to efficient diagnostic media. The amount of egg white found to be satisfactory was 10% of the final medium volume. Its conalbumin equivalent was 1.7 mg of conalbumin per ml of final medium. Such modified media are at least the equivalent of the medium recommended for the evaluation of this important characteristic.
Cultural Characteristics and Fatty Acid Composition of
Corynebacterium acnes
Authors: Moss C. Wayne , Dowell V. R. , Lewis V. J. , Schekter M. A.
Published: January 2020

A detailed study of the cultural characteristics and cellular fatty acid composition of 27 isolates of
Corynebacterium acnes
was performed to establish the properties by which this organism may be identified and characterized. The fatty acids were extracted directly from whole cells and examined as methyl esters by gas-liquid chromatography. Each strain possessed a similar fatty acid profile which was characterized by a large percentage of C15 branched-chain acid. Uniformity in certain biochemical reactions and cultural characteristics was also observed. All strains were catalase-positive, nonmotile, and urease-negative, reduced nitrate, liquefied gelatin, failed to hydrolyze esculin and starch, and gave a positive methyl red test. Glucose, fructose, and glycerol were fermented, but not lactose, salicin, sucrose, maltose, xylose, or arabinose. Production of hydrogen sulfide and indole, fermentation of mannitol, and hemolytic activity were variable characteristics. Two species of the genus
Propionibacterium
were also tested and found to be similar to
C. acnes
both in cultural characteristics and fatty acid composition. The results strengthen previous suggestions that
C. acnes
should be classified in the genus
Propionibacterium
.
Staphylococcal β-Hemolysin II. Phospholipase C Activity of Purified β-Hemolysin
Authors: Maheswaran S. K. , Lindorfer Robert K.
Published: January 2020

Sheep erythrocyte ghosts released water-soluble organic phosphorus when treated with purified β-hemolysin. Phospholipid analysis demonstrated that sphingomyelin accounted for 53% of the phospholipids present in sheep erythrocytes. Purified β-hemolysin showed phospholipase C activity when purified ox brain or sheep erythrocyte sphingomyelin was used as substrate. Such studies have also revealed that the disappearance of sphingomyelin from the reaction mixture was accompanied by a comparable increase in the concentration of phosphoryl choline. Thin-layer chromatography of phospholipids, extracted from sheep erythrocytes which had been exposed to β-hemolysin, demonstrated that sphingomyelin was rapidly degraded. Activators of β-hemolysin, such as Mg
++
, enhanced the release of organic phosphorus from erythrocyte ghosts and from sphingomyelin. Inhibitors of β-hemolysin, such as ethylenediaminetetraacetic acid,
p
-chloromercuribenzoate, and iodoacetamide, also inhibited the release of organic phosphorus from erythrocyte ghosts and from sphingomyelin. These studies strongly suggested that β-hemolysin enzymatically degraded the sphingomyelin of the erythrocyte membrane. Such degradation probably resulted in the eventual lysis of the erythrocyte.
Biologically Active Endotoxins from
Salmonella
Mutants Deficient in O- and R-Polysaccharides and Heptose
Authors: Kim Yoon Berm , Watson Dennis W.
Published: January 2020

Well-characterized
Salmonella
mutants formerly used in biosynthetic studies of lipopolysaccharides were used to study the toxic portion of the complex endotoxin. Endotoxins prepared from wild types and their mutants were tested for their biological activities, including pyrogenicity, lethality, and immunogenicity. There was little difference either in the endotoxin yields or in the toxicities between endotoxins from the wild-type and O-antigen deficient mutants. Endotoxin containing mostly lipid A and keto-deoxyoctonate (KDO) prepared from the mutant deficient in both O- and R-antigens and the backbone sugar, heptose, was biologically active. Possibly because of the difference in solubility in water, the yield of endotoxin from the heptoseless mutant was about 10% of the wild type. There was complete reciprocal cross-immunity between all endotoxins tested. These observations suggest that the common toxic moiety is not present in the O- and R-polysaccharides or the backbone sugar heptose, but rather is associated with the lipid portion of the molecule which includes mostly lipid A and KDO.
In Vivo and In Vitro Action of Norethindrone on Staphylococci
Authors: Yotis William W.
Published: January 2020

Norethindrone has been examined in vitro for antibacterial activity against 10 microorganisms. Turbidimetric techniques were used to assay the antibacterial activity of norethindrone. The organisms tested included
Staphylococcus aureus, S. epidermidis, Micrococcus conglomeratus, Listeria monocytogenes, Streptococcus faecalis, Salmonella typhosa, Shigella flexnerii, Klebsiella pneumoniae, Escherichia coli
, and
Proteus vulgaris
. Bacteriostatic action was shown only against the gram-positive microorganisms when they were grown anaerobically in Tryptic Soy Broth containing 10 to 50 μg of norethindrone per ml. The bacteriostatic action of norethindrone was exerted primarily during the first 8 hr of incubation and it was reduced by the presence of oxygen. Mestranol at a concentration of 1 to 10 μg/ml failed to exert any significant action on
S. aureus
. However, incorporation of 5 μg of mestranol per ml in the culture medium enhanced the bacteriostatic action of norethindrone on staphylococci. Enhancement of the bacteriostatic action of norethindrone could not be obtained by the addition of a concentration of 5 μg/ml of testosterone, 17α-estradiol, and 17β-estradiol. Progesterone and 4-pregnen-20β-ol-3-one under similar conditions showed an additive bacteriostatic effect when they were incorporated into the culture medium containing norethindrone. In vivo studies indicated that female, adult New Zealand rabbits, injected subcutaneously with two injections of 10 to 20 μg of norethindrone, 24 hr apart, and challenged intradermally with
S. aureus
4 hr after the second injection, had fewer lesions with smaller areas of swelling and erythema as compared to control, nontreated rabbits. The protective effect of norethindrone on the development of staphylococcal lesion seemed related to hormone concentration. Thus, it was demonstrated with doses of 20, 15, and 10 μg, but not with doses of 1 and 5 μg. When the lesions were excised 48 to 92 hr after infection and when viable cell counts were made, rabbits treated with norethindrone showed significantly lower staphylococcal counts than the control rabbits. During the 1st day after infection with
S. aureus
, leukocytic counts of the norethindrone-treated rabbits remained normal, whereas control animals showed elevated leukocytic counts.
Development of Immune Tolerance in the Chick Embryo to
Borrelia hispanica
Authors: Hanson Albert W. , Cannefax George R.
Published: January 2020

Varying degrees of immune tolerance were induced in chick embryos at 10, 14, and 18 days of age by inoculation of living or dead
Borrelia hispanica
in the yolk sac, allantoic cavity, or intravenously. Relative tolerance was measured by responses to challenge with virulent organisms in relation to altered susceptibility to infection and inability to produce agglutinins for
B. hispanica
or
Proteus
strain OXK. Challenges were made 1 week posthatching with the controls and chicks that had received dead organisms embryonically, and all chicks and controls were challenged at 5-week intervals from the 5th through the 30th week posthatching. Infections persisted 7 to 12 days in the tolerant chicks without a recurring parasitemia. Control chicks were never infected, and in almost all instances produced agglutinins. Differences in degree and duration of tolerance were observed in relation to the age of the embryo injected and may, or may not, have been related to differences of antigenic mass. Differences in induced tolerance were also observed in the three inoculation routes (intravenous > allantoic cavity > yolk sac, with the first route as the greatest) with chicks that had received dead organisms embryonically, but not with those that had received living organisms. Tolerance was not transmitted to the progeny of tolerant pullets.
Cell Walls of Group D Streptococci II. Chemical Studies on the Type 1 Antigen Purified from the Autolytic Digest of Cell Walls
Authors: Bleiweis Arnold S. , Young Frank E. , Krause Richard M.
Published: January 2020

Autolysis of group D, type I cell walls by an indigenous autolytic enzyme results in the solubilization of the type I antigen. The antigen was purified from the autolytic digest by diethylaminoethyl cellulose chromatography. Chemical analysis of the purified type 1 antigen revealed glucose, glucosamine, galactosamine, rhamnose, ribitol, phosphorus, and residual peptoglycan components. This analysis suggested that the type I antigen is a heteropolymer which may contain a ribitol teichoic acid. The antigen purified by the procedure outlined here is higher in phosphorus content, lower in peptidoglycan, and more reactive serologically than the antigen prepared by methods previously described.
Complement and Lysozyme Requirements for Spirochetolysis in Guinea Pig Serum
Authors: Nevin T. A. , Guest W. J.
Published: January 2020

During experiments on the immunological immobilization of treponemes, several cultured strains were lysed in the guinea pig serum used as a source of complement. In further studies employing
Borrelia vincentii
, lysis, observed by darkfield, appeared as swelling and some beading of the cells. Complete disruption eventuated. Untreated guinea pig serum was strongly lytic, whereas little or no lysis occurred in bentonite-adsorbed samples. Activity was restored to these samples by adding commercially obtained crystalline egg-white lysozyme. Serum samples which had been heated, absorbed with aggregates of human γ-globulin, or treated with ethylenediaminetetraacetate to remove, or inactivate, complement also lost spirochetolytic activity.
Serological Comparison of Spherules and Arthrospores ofCoccidioides immitis
Authors: Landay Marshall E. , Wheat Robert W. , Conant Norman F. , Lowe Edwin P.
Published: January 2020

Spherule and arthrospore cellular preparations were sonic-treated and separated into their respective supernatant and sediment components. Complement-fixation tests with antispherule and antiarthrospore pooled rabbit sera revealed that the soluble antigens exhibited more serological activity than the sediment preparations. After autoclaving, an arthrospore cellular antigen exhibited increased activity with either antisera, whereas autoclaved spherules exhibited increased activity only with antispherule serum. Complement-fixation tests with coccicioidin and spherule culture supernatant preparations revealed quantitative or qualitative differences in antigenic determinants between these two morphological phases ofCoccidioides immitis.
Physicochemical Properties of the Vi Antigen Before and After Mild Alkaline Hydrolysis
Authors: Jarvis Francis G. , Mesenko Marianne T. , Martin Donald G. , Perrine Theodore D.
Published: January 2020

Sedimentation and diffusion constants were determined for electrophoretically purified Vi antigen before and after mild alkaline hydrolysis. The molecular weight of the intact antigen was found to be 1.7 × 10
6
. Mild alkaline hydrolysis completely removed
O
-acetyl, reduced the molecular weight to 1.0 × 10
5
, and lowered the intrinsic viscosity from 8.0 deciliters/g to approximately 0.5 deciliter/g. Infrared spectra of the two antigen preparations were also compared.
Physicochemical and Biological Properties of Sonically Treated Vi Antigen
Authors: Martin Donald G. , Jarvis Francis G. , Milner Kelsey C.
Published: January 2020

Electrophoretically purified Vi antigen fromCitrobacter freundii5396/38 was depolymerized by sonic treatment. The treatment caused an 80% reduction in specific viscosity and a reduction in molecular weight from 1.6 × 106to 3.9 × 104. TheO-acetyl andN-acetyl contents of the antigen and its infrared spectrum remained unchanged. The sonically treated antigen was only 1% as effective as the original antigen in eliciting protection in mice against challenge withSalmonella typhi. Sonically treated antigen also elicited lower antibody titers after single injections in mice and rabbits. No loss in ability to precipitate antibody or to sensitize red blood cells for hemagglutination was observed.
Role of the Phagocyte in Host-Parasite Interactions XI. Relationship Between Stimulated Oxidative Metabolism and Hydrogen Peroxide Formation, and Intracellular Killing
Authors: McRipley R. J. , Sbarra A. J.
Published: January 2020

The increased respiratory and hexose monophosphate activities noted in phagocytizing cells results in the formation of hydrogen peroxide. This is brought about by the oxidation of reduced nicotinamide adenine dinucleotide phosphate by its oxidase. Evidence is presented which indicates that this H
2
O
2
is involved in the intracellular killing of bacteria. When molecular oxygen was excluded from phagocytizing leukocytes by anaerobiosis, thus inhibiting H
2
O
2
formation, reduced intracellular killing was observed. In some cases the impairment of leukocytic bactericidal activity by anaerobiosis could be partially reversed by the addition of H
2
O
2
. Exogenous catalase also could reduce intracellular killing. In addition, when leukocytic isolates were dialyzed so as to reduce endogenous H
2
O
2
, the bactericidal activity of the leukocytes was significantly decreased under both aerobic and anaerobic conditions. These results occurred with both guinea pig and human leukocytes and with several test microorganisms.
Inhibitio of Flagellar Coordination in
Spirillum volutans
Authors: Krieg Noel R. , Tomelty Joseph P. , Wells J. Scott
Published: January 2020

The motility of
Spirillum volutans
is caused by the rotation of each polar flagellar fascicle in a direction opposite to that of the more slowly rotating cell. Both flagella form cones of revolution oriented in the same direction. When the cell reverses its motion, both fascicles simultaneously reverse their rotation and also the orientation of their cones of revolution, with the tail fascicle becoming the head and vice versa. Chloral hydrate and phenol were found to cause uncoordination, with both fascicles becoming the head type; MgSO
4
, Mg(NO
3
)
2
, NiSO
4
, NiCl
2
, CuSO
4
, and CuCl
2
also caused uncoordination, with both fascicles becoming the tail type. In all cases, the flagellar fascicles remained highly active but the cells were motionless because of the opposing propulsion; the rotation of the fascicles was in a constant direction without reversal. Uncoordinated states could be maintained for 30 to 60 min. Neutralization of the dual-tail flagellation caused by NiSO
4
could be accomplished with chloral hydrate. At the null point, the flagellar orientation was intermediate between head and tail; the fascicles continually reversed direction of rotation, and, now coordinated, caused the cells to move back and forth. Higher concentrations of chloral hydrate completely overcame the effect of NiSO
4
and caused dual-head flagellation. Optimal concentrations of test compounds were determined with the use of pure cultures and a reproducible growth medium.
Energies of Activation and Uncoupled Growth in
Streptococcus faecalis
and
Zymomonas mobilis
Authors: Forrest W. W.
Published: January 2020

Growing cultures of
Streptococcus faecalis
at temperatures above 30 C have activation energies for both rates of growth and glycolysis of 10.3 kcal mole
−1
, and a constant growth yield; when growth takes place below this temperature, the growth yield decreases and the activation energy for growth increases to 21.1 kcal mole
−1
, but the activation energy for glycolysis is unchanged. The adenosine triphosphate pool in the organisms behaves differently above and below 30 C, suggesting that the energetic coupling between anabolism and catabolism is less effective below 30 C. Washed suspensions of
S. faecalis
have repressed glycolytic activity and an activation energy for glycolysis of 15.6 kcal mole
−1
over the whole temperature range studied. Growing cultures of
Zymomonas mobilis
below 33 C have a constant growth yield of 8.3 g (dry weight) of organisms per mole of glucose degraded, and activation energies for both glycolysis and growth of 11.1 kcal mole
−1
; above this temperature, the growth yield falls, the activation energy for growth changes to −6.9 kcal mole
−1
, but the activation energy for glycolysis is unchanged, so that the coupling between anabolism and catabolism is less effective above 33 C. The findings support the view that energy turnover in these bacteria is not well regulated.
Enhancement of
Agrobacterium tumefaciens
Infectivity by Mitomycin C
Authors: Heberlein Gary T. , Lippincott James A.
Published: January 2020

The ability of
Agrobacterium tumefaciens
to induce pinto leaf tumors may be enhanced two- to threefold after treatment with mitomycin C. The enhancement may be obtained with either lethal or nonlethal concentrations. With 10-min treatments, an optimal response was obtained with 0.005 μg of mitomycin C per ml in the absence of any change in the number of viable cells. Both the tumor induction process and the tumors induced by treated cultures appear qualitatively the same as controls. To account for these results, the antibiotic must increase the proportion of viable cells that will subsequently initiate tumors. One, or at most a few, random lesions in the bacterial chromosome seem to be the necessary requirement for this promotion. At mitomycin concentrations of 1 and 5 μg/ml, the ability of
A. tumefaciens
to initiate tumors is rapidly lost, indicating that a fairly intact bacterial chromosome is one of the essentials for the tumor induction process.
Derepression of Phosphomannose Isomerase by Regulator Gene Mutations Involved in Capsular Polysaccharide Synthesis in
Escherichia coli
K-12
Authors: Markovitz Alvin , Lieberman Michael M. , Rosenbaum Nancy
Published: January 2020

A regulator gene mutation (
capR
) that causes increased synthesis of capsular polysaccharide and derepressed synthesis of several enzymes involved in polysaccharide synthesis also derepresses phosphomannose isomerase (PMI) synthesis. In contrast, a second mutation (
capS
, which maps separately from
capR
) that causes increased production of the same polysaccharide does not lead to increased synthesis of PMI (nor of several of the other enzymes involved in polysaccharide synthesis). Introduction of the
capR9
allele by transduction or mutation of
capR
+
to
capR
can change the phenotype of a mannose-negative nonmucoid strain to a mannose-positive mucoid phenotype. Thus, genotype
capR
+
man-2
is mannose-negative and nonmucoid, but genotype
capR9 man-2
is mannose positive and mucoid. Other interactions between these alleles in the synthesis of capsular polysaccharide are recorded.
Penicillin Acyltransferase in
Penicillium chrysogenum
Authors: Pruess David L. , Johnson Marvin J.
Published: January 2020

Isotopic exchange of
35
S between penicillins and 6-amino-penicillanic acid (6-APA) was observed in cell-free extracts of
Penicillium chrysogenum
. Sulfhydryl-containing compounds were required for activity. Dithiothreitol, dithioerythritol, mercaptoethanol, and glutathione served as activators. The acyltransferase was purified threefold by adsorption on calcium phosphate gel at
p
H 6 and elution at
p
H 8. The partially purified enzyme showed maximal activity at
p
H 8. The enzyme was stable at 25 C for at least 30 min at
p
H 8. Dissociable inhibitors or activators, other than the sulfhydryl-containing compounds, could not be demonstrated in the enzyme preparation. An apparent Michaelis constant of 1.5 ± 0.5 m
m
was determined for penicillin G at a 6-APA concentration of 5 m
m
. The enzyme did not appear to possess penicillin amidase activity. The exchange mechanism probably involves an acyl-enzyme intermediate. Penicillins V, G, K, X, and dihydro F showed isotopic exchange with
35
S-6-APA. Penicillin N, methylpenicillin, and phenyl-penicillin did not show exchange. The level of acyltransferase in
P. chrysogenum
51-20F3 was measured at times during the fermentation. The level of activity increased threefold between 40 and 55 hr, remaining high until about 90 hr.
Carbohydrate Metabolism in Streptomycetes II. Isolation and Enzymatic Synthesis of Trehalose
Authors: Elbein Alan D.
Published: January 2020

A number of streptomycetes were examined for their ability to synthesize trehalose phosphate as well as for the presence of α,α-trehalose. In each case, an enzyme system was demonstrated which catalyzed the transfer of glucose from guanosine diphosphate-glucose to glucose-6-phosphate to form trehalose phosphate. Thus, this group of organisms appears to synthesize trehalose phosphate by a different mechanism from that described in insects, yeast, and fungi. In addition, trehalose was isolated from each of these organisms. In several of these cases, crystallization of the sugar and determination of the physical properties showed that the sugar was α,α-trehalose.
Dominant Mutation for Ethionine Resistance in
Saccharomyces cerevisiae
Authors: Spence K. D. , Parks L. W. , Shapiro S. K.
Published: January 2020

An ethionine-resistant mutant of
Saccharomyces cerevisiae
has been investigated whose mutation (
et
r2
) confers resistance to the heterozygous diploid also containing the sensitive allele,
et
s
. The mutation is apparently specific for reversal of ethionine inhibition. The principal difference between the sensitive
et
s
strain and the mutant was the latter's inability to concentrate large intracellular quantities of adenosylethionine. Reduced incorporation of ethyl groups or ethionine in other cellular fractions of the mutant was also detected. The data show that the mutant has not lost the ability to form adenosylethionine. It is suggested that the mutant has an increased ability to hydrolyze this sulfonium compound after it has been synthesized. It is possible that some of the ethionine is detoxified before it can participate in protein or adenosylethionine synthesis. No mutant alteration in accumulation of ethionine from the medium was detected. In the presence of ethionine, the parental strain accumulated 25 times more adenosylethionine than did the mutant. However, with methionine, only twice as much adenosylmethionine was accumulated by the parental strain as by the mutant.
Thymidine and Thymine Incorporation into Deoxyribonucleic Acid: Inhibition and Repression by Uridine of Thymidine Phosphorylase of
Escherichia coli
Authors: Budman Daniel R. , Pardee Arthur B.
Published: January 2020

Thymidine is poorly incorporated into deoxyribonucleic acid (DNA) of
Escherichia coli
. Its incorporation is greatly increased by uridine, which acts in two ways. Primarily, uridine competitively inhibits thymidine phosphorylase (E.C.2.4.4), and thereby prevents the degradation of thymidine to thymine which is not incorporated into normally growing
E. coli
. Uridine also inhibits induction of the enzyme by thymidine. It prevents the actual inducer, probably a deoxyribose phosphate, from being formed rather than competing for a site on the repressor. The inhibition of thymidine phosphorylase by uridine also accounts for inhibition by uracil compounds of thymine incorporation into thymine-requiring mutants. Deoxyadenosine also increases the incorporation of thymidine, by competitively inhibiting thymidine phosphorylase. Deoxyadenosine induces the enzyme, in contrast to uridine. But this is offset by a transfer of deoxyribose from deoxyadenosine to thymine. Thus, deoxyadenosine permits incorporation of thymine into DNA, even in cells induced for thymidine phosphorylase. This incorporation of thymine in the presence of deoxyadenosine did not occur in a thymidine phosphorylase-negative mutant; thus, the utilization of thymine seems to proceed by way of thymidine phosphorylase, followed by thymidine kinase. These results are consistent with the data of others in suggesting that wild-type
E. coli
cells fail to utilize thymine because they lack a pool of deoxyribose phosphates, the latter being necessary for conversion of thymine to thymidine by thymidine phosphorylase.
Ribosyl and Deoxyribosyl Transfer by Bacterial Enzyme Systems
Authors: Imada Akira , Igarasi Seizi
Published: January 2020

The enzymatic transfer of ribose and deoxyribose residues in pyrimidine nucleosides to purines was catalyzed by cell-free extracts of various bacteria. Almost all the strains belonging to
Enterobacteriaceae
were capable of catalyzing the transfer reactions. The transfer activities were also detected among some bacterial strains of other families:
Pseudomonadaceae, Corynebacteriaceae, Micrococcaceae, Bacteriaceae
, and
Bacillaceae
. The rates of the transfer reactions were greatly enhanced in the presence of phosphate ion, and the participation of nucleoside phosphorylases in the reactions was suggested. Uridine phosphorylase, thymidine phosphorylase, and purine nucleoside phosphorylase were purified from cell-free extract of
Aerobacter aerogenes
IFO 3321. The ribosyl transfer from uridine to hypoxanthine was found to be catalyzed by the coupled reactions of uridine and purine nucleoside phosphorylases and the deoxyribosyl transfer from thymidine to hypoxanthine by the coupled reactions of thymidine and purine nucleoside phosphorylases.
Unusual Growth Characteristics of a Methionine-Cyano-B
12
Auxotroph of
Escherichia coli
Authors: Dickerman Herbert , Taylor Robert T. , Weissbach Herbert
Published: January 2020

Escherichia coli
K-12, strain AB1172, substrain 2276, a methionine
−
-cyano-B
12
−
auxotroph grew poorly when placed in a medium containing optimal levels of cyano-B
12
and suboptimal amounts of
l
-methionine. A marked depression of
N
5,10
-methylene-H
4
-folate reductase was observed in the inhibited cells, although no significant alterations in other enzymes involved in the metabolism of
N
5,10
-methylene-H
4
-folate were observed. Guanosine was effective in preventing the growth inhibition.
An Upper Limit on β-Galactosidase Transfer in Bacterial Conjugation
Authors: Rosner J. L. , Adelberg Edward A. , Yarmolinsky Michael B.
Published: January 2020

An upper limit for β-galactosidase transfer between mating F
+
and F
−
Escherichia coli
has been determined by a new technique which relies on selective lysis of the donor strain by heat induction of a thermo-inducible strain of λ, accompanied by chymotryptic digestion of the released β-galactosidase. No significant transfer of β-galactosidase during mating between F
+
and F
−
cells has been observed: 0.05 ± 0.05% of the enzyme originally present in the male cells is found in the female cells after 1 hr of mating at 37 C.
Multiple Alterations in Metabolite Uptake in a Mutant of
Neurospora crassa
Authors: Kappy Michael S. , Metzenberg Robert L.
Published: January 2020

A temperature-conditional lethal mutant of
Neurospora crassa, un-t
(
55701
), was resistant to neutral amino acid analogues by virtue of a decreased ability to transport these analogues and their natural congeners across the cell membrane. The uptake of acidic, but not basic, amino acids was also impaired, as was the uptake of potassium ions. After preincubation above the tolerated temperature, the ability to take up a still wider variety of metabolites was greatly reduced. Protoplasts of the mutant were more osmotically fragile than those of wild type. The possibility that the mutant has a generalized membrane defect is discussed.
Phospholipids of
Thiobacillus thiooxidans
Authors: Shively J. M. , Benson A. A.
Published: January 2020

Cells and spent growth media from sulfur- and thiosulfate-grown cultures of
Thiobacillus thiooxidans
were analyzed. The phosphatides were examined by thinlayer chromatography, and the products of their hydrolysis by hydrochloric acid and methanolic potassium hydroxide were separated by paper chromatography. The phospholipids in both cells and spent growth media were identified as phosphatidyl ethanolamine, phosphatidyl-
N
-monomethylethanolamine, phosphatidyl glycerol, and diphosphatidyl glycerol. These comprised about 97% of the total lipid phosphorus. Lyso-phosphatidyl-
N
-monomethylethanolamine and lysophosphatidyl glycerol accounted for the remaining 3%. The percentage of the total lipid phosphorus accounted for by each phospholipid depended on the age of the culture.
Nonselective Incorporation into Sporangium of Either “Older” or “Younger” Chromosome of the Vegetative Cell During Sporulation inBacillus cereus
Authors: Kogoma Tokio , Yanagita Tomomichi
Published: January 2020

EmployingBacillus cereusstrain 2, we examined the fate of two chromosomes contained in vegetative cells in the course of sporulation. Cytological observations and quantitative estimation of deoxyribonucleic acid (DNA) confirmed the earlier observations that, during the course of sporulation, one of two chromosomes of the vegetative cell was incorporated into the sporangium and the other disappeared into the medium as the result of cell lysis. Log-phase cells, labeled completely with thymine-2-14Cin the presence of deoxyadenosine, were cultured in the “cold” glucose-glutamate-glycine-salts medium, and culture samples, taken at intervals at successive generations, were subjected to sporulation in glutamate-salts medium. The percentage of radioactivity in the spores separated from each culture remained almost unchanged at nearly 50% and was independent of the number of generations of the preceding culture in the “cold” medium. This suggests that the selective incorporation into the sporangium of either the “older” or “younger” chromosome of a vegetative cell does not occur in the course of spore formation. Some examples of the selective and nonselective behavior of DNA molecules in cellular events in microorganisms are cited.
Nutrition and Metabolism of Marine Bacteria XVI. Formation of Protoplasts, Spheroplasts, and Related Forms from a Gram-negative Marine Bacterium
Authors: Costerton J. W. , Forsberg Cecil , Matula Tibor I. , Buckmire F. L. A. , MacLeod Robert A.
Published: January 2020

When cells of a marine pseudomonad were washed and suspended in 0.5
m
sucrose, they retained their rod shape, but thin sections, when examined in an electron microscope, revealed that the outer layer of the cell wall had separated a considerable distance from the cytoplasmic membrane. Treatment of such cells with lysozyme alone produced no obvious change, but treatment with ethylenediaminetetraacetic acid (EDTA) alone caused the outer wall to disappear. A combination of EDTA and lysozyme resulted in the rapid formation of spheres essentially free from hexosamine and indistinguishable from protoplasts of gram-positive bacteria. When cells were washed with 0.5
m
NaCl and then suspended in 0.5
m
sucrose, they also retained their rod shape, but in this case the outer layer separated from the cells completely and could be recovered from the suspending medium. Such cells were converted to protoplasts by the action of lysozyme alone. Cells washed and finally suspended in 0.5
m
NaCl, when treated with EDTA and lysozyme, slowly became spherical. Thin sections revealed typical spheroplasts of gram-negative bacteria in which the outer wall remained intact. Protoplasts took up α-aminoisobutyric acid by a Na
+
-dependent process.
Influence of Carbon Tetrachloride on Inducible Liver Enzymes and Response to Endotoxin in Mice
Authors: Snyder Irvin S. , Agarwal Manjul K. , Berry L. Joe
Published: January 2020

Injection of mice with a sublethal dose of endotoxin 2 hr after administration of 0.1 ml of carbon tetrachloride (CCl
4
) killed 75% of the animals. CCl
4
alone killed no controls. Significant protection against this effect was afforded by 5 mg of cortisone and by 5 mg of nicotinamide adenine dinucleotide (NAD). With a larger dose of endotoxin, cortisone did not give protection. Liver tryptophan pyrrolase activity was lowered 2 hr after CCl
4
injection and reached a minimum after 17 hr. Induction of tryptophan pyrrolase by cortisone, followed by administration of CCl
4
, resulted in rapid loss of activity. A significant induction of tyrosine-α-ketoglutarate transaminase was observed in CCl
4
-treated mice. The induction of this enzyme by cortisone was somewhat impaired when CCl
4
was administered concurrently with the hormone. CCl
4
did not lower tryptophan pyrrolase in endotoxin-tolerant mice after 4 hr, but at 17 hr the activity was decreased as much as in control mice. Oxidized pyridine nucleotides were decreased 17 hr after administration of CCl
4
. This loss was prevented by administration of NAD (5 mg) or by cortisone (5 mg). Carbon clearance from blood was reduced after treatment with CCl
4
. These results indicate a degree of similarity between the metabolic effects of endotoxin and CCl
4
in that both depress tryptophan pyrrolase and prevent its induction by cortisone, and both induce tyrosine transaminase in intact mice. Both substances appear to exert these effects through some type of mediated reaction.