bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Endotoxin on Tumor Resistance in Mice
Authors: Yang Cynara , Nowotny Alois
Published: January 2020

As reported earlier, an intraperitoneal injection of 1 μg of endotoxin (ET) from
Serratia marcescens
rendered mice resistant against the nonspecific mouse ascites tumor TA3-Ha upon challenge 24 h after pretreatment with ET. Further studies were aimed at the elaboration of conditions which achieved maximal resistance. It appears that (i) a 10-μg dose of ET was approximately the optimal dose for protection; (ii) pretreatment with ET 3 to 0 days prior to tumor challenge gave best protection; and (iii) the intravenous injection of ET showed a lower protection against the tumor than intraperitoneal application. Studies on the mechanism of ET protection indicate that (i) ET does not have a direct cytotoxic effect on tumor cells; (ii) normal spleen cells exposed to ET in vitro can adoptively transfer protection against tumor; and (iii) spleen cells activated in vivo by intravenous injection of ET can adoptively transfer protection. The possible involvement of mononuclear cells is discussed.
Pathogenesis of Rinderpest Virus Infection in Rabbits I. Clinical Signs, Immune Response, Histological Changes, and Virus Growth Patterns
Authors: Yamanouchi Kazuya , Chino Fumitoshi , Kobune Fumio , Fukuda Akiko , Yoshikawa Yasuhiro
Published: January 2020

Rabbits were intravenously inoculated with an attenuated rinderpest virus (L strain), and general patterns of the disease were investigated. The rabbits developed fever with concomitant occurrence of diarrhea and lymphopenia. Early production of interferon was followed by a rise of neutralizing antibody. Histological examinations revealed an involvement of all of the lymphoid tissues, with primary lesions consisting of necrosis of the lymphoid follicles and formation of giant cells. Immunofluorescent examinations suggested that the virus growth was present in almost all of the lymphoid tissues. The possibility of application of this experimental system for the study of systemic infection by measles virus was discussed.
Fusion of Normal Rabbit Alveolar Macrophages Induced by Supernatant Fluids from BCG-Sensitized Lymph Node Cells After Elicitation by Antigen
Authors: Galindo B. , Lazdins J. , Castillo R.
Published: January 2020

Cell-free supernatant fluids obtained from BCG-sensitized lymph node cells (6 × 10
6
cell/ml) incubated in tissue culture flasks containing heat-killed BCG (5 μg/ml) induced extensive development of multinucleated giant cells when incubated with normal alveolar macrophages. In contrast, supernatant fluids obtained after incubation of similar samples of the same lymph node cell population in flasks with (i) no mycobacteria, (ii) heat-killed
Escherichia coli
, or (iii) heat-killed
Bacillus subtilis
failed to produce giant cells when added to normal alveolar macrophages. Giant-cell formation was observed in experiments using
Nocardia brasiliensis
as the eliciting antigen, indicating cross-reactivity between the antigens of this organism and BCG. These experiments indicate that BCG-sensitized lymphoid cells produce a soluble macrophage fusion factor after specific antigen stimulation. The fusion factor is a nondialyzable substance which is resistant to heating at 80 C for 30 min.
Antibody-Mediated Inhibition of Dextran/Sucrose-Induced Agglutination of
Streptococcus mutans
Authors: Olson Gerald A. , Guggenheim Bernard , Small Parker A.
Published: January 2020

Immune sera to strains of
Streptococcus mutans
were found to inhibit agglutination of bacterial suspensions to which either high-molecular-weight dextran or sucrose was added. This inhibitory activity was shown to be mediated by antibody of the immunoglobulin G class. A semiquantitative assay was developed which demonstrated cross-inhibition of dextran/sucrose-induced agglutination among several strains of
S. mutans
. Antiserum to a partially purified glucosyltransferase was found to lack agglutination inhibition activity, consistent with the hypothesis that the dextran-binding antigen detected by the assay is immunologically distinct from the glucan-synthetic enzyme. A model for glucan synthesis and binding consistent with the reported data is described.
Bactericidal Activity of Aerobic and Anaerobic Polymorphonuclear Neutrophils
Authors: Mandell Gerald L.
Published: January 2020

Human polymorphonuclear neutrophils (PMN) were made anaerobic by nitrogen washout (oxygen saturation <1%, Eh < −42 mV at pH 7.0), and the ability of the cells to kill bacteria was assayed and compared to the bactericidal activity of aerobic PMN. Anaerobic PMN were able to kill
Staphylococcus epidermidis, Enterococcus
, viridans streptococci,
Pseudomonas aeruginosa, Peptostreptococcus anaerobius, Bacteroides fragilis, Clostridium perfringens
, and
Peptococcus magnus
normally. Organisms that were not killed normally by anaerobic PMN included
Staphylococcus aureus
(strains Wood 46 and 502a),
Escherichia coli, Serratia marcescens, Klebsiella pneumoniae, Proteus vulgaris
, and
Salmonella typhimurium.
These findings suggest that mechanisms other than those dependent on hydrogen peroxide may be important in the killing of some bacteria.
Thymus-Dependent Lymphocytes of Peripheral Blood in Leprosy Patients
Authors: Lim Soo-Duk , Kiszkiss David F. , Jacobson Robert R. , Choi Yong Sung , Good Robert A.
Published: January 2020

Study of the numbers of thymus-derived lymphocytes by the rosette assay (T-RFC) in patients with leprosy reveals that lower than normal numbers of T-RFC are regularly seen in those patients with the active lepromatous form of this disease. Essentially normal numbers of T-RFC were found in inactive lepromatous, borderline, and indeterminate types of leprosy. The lowest percentages and lowest absolute numbers of T-RFC were encountered in patients with lepromatous leprosy resistant to chemotherapy. Patients with lepromatous leprosy complicated by erythema nodosum leprosum show numbers of T-RFC that are more nearly normal than the numbers of T-RFC in patients with uncomplicated lepromatous leprosy. These findings are discussed with respect to the pathogenesis of lepromatous leprosy and the T-RFC deficiency demonstrated in this disease. The possibility that transient defects in T-RFC numbers or function may predispose to lepromatous leprosy is proposed.
Immunity in Experimental T-Mycoplasma Mastitis
Authors: Howard C. J. , Gourlay R. N. , Brownlie J.
Published: January 2020

Immunity to reinfection with the homologous T-mycoplasma strain has been demonstrated in the bovine mammary gland. This immunity was generalized throughout the udder and was not confined to previously infected quarters. Two out of three cows which were immune to reinfection with the homologous strain were not immune to reinfection with a serologically distinct T-mycoplasma strain. Animals varied in their ability to resolve experimental mastitis with T-mycoplasmas: those which resolved the initial infection without antibiotic therapy were immune to challenge with the homologous strain, but those which needed to be given antibiotics to clear the first infection were not all immune to such challenge.
Biological and Physical Properties of the Suckling Mouse Cataract Agent Grown in Chicken Embryos
Authors: Bastardo Jesus W. , Ou David , Bussell Robert H.
Published: January 2020

Experiments were carried out with the suckling mouse cataract agent (SMCA) in an attempt to better characterize the nature of this agent. Despite the fact that high titers of SMCA were found in the chorioallantoic fluid of inoculated chicken embryos, the agent did not replicate in chicken embryo epithelial cell cultures. SMCA did not interfere with Sindbis virus plaque formation and was not inhibited by chicken interferon or polyinosinic-polycytidylic acid. The agent was relatively resistant to high pH and osmotic shock but was inactivated by low pH. Electron micrographs of negatively stained particles concentrated and semipurified from infected chicken embryo chorioallantoic fluids revealed pleomorphic particles ranging from approximately 70 to 400 nm in diameter. SMCA was resistant to kanamycin, novobiocin, and sodium aurothiomalate.
Evaluation of Dextranase Production by the Cariogenic Bacterium
Streptococcus mutans
Authors: Staat Robert H. , Schachtele Charles F.
Published: January 2020

A recently developed blue dextran-agar assay was utilized to detect dextranase production by a large number of strains of
Streptococcus mutans.
An extract obtained from
S. mutans
strain B2 hydrolyzed high-molecular-weight radioactive dextran to oligosaccharides. There are several possible roles for this enzyme activity in the metabolism of
S. mutans
dextrans.
Surface Properties of Extracellular Malaria Parasites: Morphological and Cytochemical Study
Authors: Seed Thomas M. , Aikawa Masamichi , Sterling Charles , Rabbege John
Published: January 2020

Morphological and cytochemical surface characteristics of isolated malaria parasites (
Plasmodium berghei
) and host erythrocytes were compared by electron microscopy by using thin section and carbon replica techniques. Erythrocytes were uniform in shape and had fine, granular surfaces. In contrast, free parasites exhibited a variety of sizes, shapes, and surface textures. Fine surface stippling was a common topographical feature of isolated parasites. Small, infective forms often had patterned surfaces resulting from the protuberance of an underlying thick intermediate layer. Results of cytochemical analysis using a sialophilic colloidal iron stain indicated that the malaria parasite's surface lacked exposed sialic acid groups which would normally give rise to a net negative surface charge common to erythrocytes. Biochemical assay demonstrated that malaria parasites contained about one-half the amount of sialic acid per unit weight as did control red cell extracts. Similarly, external acidic mucopolysaccharide coats of free parasites, as revealed by ruthenium red staining were extremely thin as compared with the thick glycocalyx layer of red cells. Lipid plaques at the surface of parasites and red cells were localized by lipophilic iron colloid staining. Although the gross patchwork distribution of plaques was somewhat similar for the two cell types, the parasites were stained more intensely and had a closer-knit patchwork pattern than those exhibited by the erythrocytes. Such findings indicate that there are slight differences in the arrangement of phospholipids at the surfaces of limiting membranes of host cells and parasites. The significance of the above cytochemical surface properties of the malaria parasite (which are seemingly akin to those of intracellular organelles is discussed in relation to certain host-parasite interactions, such as parasite adhesion to target cells and enhanced clearance of extracellular parasites.
Pathogenicity of Stable L-Phase Variants of
Staphylococcus aureus
: Failure to Colonize Normal and Oxamide-Induced Hydronephrotic Renal Medulla of Rats
Authors: Watanakunakorn Chatrchai , Bakie Cheryl
Published: January 2020

The direct intramedullary inoculation of stable L-phase variants of
Staphylococcus aureus
failed to colonize normal and hydronephrotic rat kidneys induced by oral feeding of oxamide.
Occurrence of Quinovosamine in Lipopolysaccharides of
Brucella
Species
Authors: Bowser D. V. , Wheat R. W. , Foster J. W. , Leong D.
Published: January 2020

Lipopolysaccharides obtained from
Brucella abortus, B. melitensis
, and
B. suis
, but
not B. canis
, were found to contain amino sugars identified as glucosamine and quinovosamine by cation exchange and thin-layer cellulose chromatography and ninhydrin degradation.
Delayed-Type Hypersensitivity and Immunity Against Aerogenic Tuberculosis in Guinea Pigs
Authors: Reggiardo Zulema , Middlebrook Gardner
Published: January 2020

In experiments described herein, it was observed that guinea pigs with delayed-type hypersensitivity to tuberculoproteins under various experimental conditions, with or without passive transfer of serum from immune donors, manifested no acquired immunity against aerogenically induced tuberculosis. These results are discussed in relation to the previous observations of other investigators and to the general problem of cellular hypersensitivity and immunity against facultative intracellular bacteria.
Leukocyte Migration Inhibition in Chorioretinitis
Authors: Henley Walter L. , Leopold Irving H. , Okas Sirje
Published: January 2020

Leukocyte migration inhibition (LMI) by choroid, retina, and uveal tract antigens was studied in patients with active and quiescent chorioretinal disease. LMI by retina was more frequent in both groups of patients, occurring in 9 of 16 patients with active disease and in 8 to 15 patients with disease in remission. Choroid was tested in 15 patients with active inflammation and led to LMI in 7 of them when they were off steroid therapy; it produced LMI in 3 of 13 patients whose disease appeared healed. Significant LMI was detected in three of six patients with active chorioretinitis and in one of five patients with evidence of past chorioretinopathy when their cells were tested with antigen made from pooled uveal tract tissue. The LMI test, regarded as an indicator of cell-mediated immunity, is briefly discussed. LMI by retina in over one-half of patients with chorioretinopathies appears to be a secondary event, and cellular immunity to retina may be of pathophysiological importance in the chronicity of the disorder.
Serological and Cellular Immune Activity of Peptidoglucomannan Fractions of
Candida albicans
Cell Walls
Authors: Reiss E. , Stone S. H. , Hasenclever H. F.
Published: January 2020

A two-stage extraction of isolated cell walls of
C. albicans
resulted in 45% solubilization into antigens of high molecular weight leaving a wall residue which also had antigenic properties. Ice-cold dilute alkali removed 25% of the defatted cell walls. The extract was nondialyzable, had a glucose-to-mannose ratio of 2:3 and an amino acid content of 7.32%, and was designated peptidoglucomannan (PGM). An additional 26% of the walls resistant to stage I were solubilized by sonic treatment yielding a fraction having a glucose-to-mannose ratio of 6:1, termed soluble mannoglucan (sMG). The residue after extraction and sonic treatment contained 10.9% mannose, which was the insoluble mannoglucan. The gel permeation behavior of PGM and sMG on BioGel A5M was similar; each contained two components, one estimated to exceed 5 × 10
6
molecular weight and a second smaller species. The soluble cell wall fractions were active in immunodiffusion and carried antigenic group specificity. Immunoelectrophoresis of PGM, sMG, and mannan revealed some heterogeneity. The insoluble mannoglucan had agglutinating activity. A distinctive immunodiffusion pattern of cell wall antigens was formed with the serum of a leukemic patient with candidiasis. All three cell wall antigens and mannan elicited delayed-type hypersensitivity as measured by skin-test and specific inhibition of macrophage migration. A dose of 25 μg of PGM was sufficient to inhibit 89.9% migration in the peritoneal exudates of guinea pigs immunized with cell walls, and 10 μg of PGM inhibited 91.7% migration in guinea pigs immunized with insoluble mannoglucan.
Mutation in
Shigella flexneri
Resulting in Loss of Ability to Penetrate HeLa Cells and Loss of Glycerol Kinase Activity
Authors: Kim Rosalind , Corwin Laurence M.
Published: January 2020

A colonial variant of a virulent
Shigella flexneri
2a has lost both virulence and glycerol kinase activity. It also has several other altered characteristics: lowered ability to oxidize tricarboxylic acid cycle intermediates, increased electrophoretic mobility, and decreased sensitivity to sodium lauryl sulfate. Genetic analysis has revealed that the gene governing glycerol kinase activity in
Shigella
has a different chromosomal locus than that from
Escherichia coli.
Furthermore, transduction of the
Shigella
glycerol kinase gene (
glp K
) into the avirulent
Shigella
strain can restore the ability to penetrate HeLa cells, whereas the gene from
E. coli
cannot. About half of the
glp K
mutants lose this ability, and only about half of the revertants of an avirulent
glp K
mutant regain it. This indicates that more than one gene affects glycerol kinase activity in
Shigella,
only one of which is associated with penetration. Glycerol kinase activity is closely correlated with changes in electrophoretic mobility, but does not appear to have any relationship to sodium lauryl sulfate sensitivity nor to the oxidation of tricarboxylic acid cycle intermediates.
R Factors Improving Survival of
Escherichia coli
K-12 After Ultraviolet Irradiation
Authors: Marsh Edward B. , Smith David H.
Published: January 2020

Two R factors which have the capacity to improve survival of some strains of
Escherichia coli
K-12 by approximately 60% after ultraviolet light have been identified and characterized. Both are
fi
−
, but neither produce colicins. The ability to enhance survival can be separated from all other identified R-factor functions. Improved survival does not result from improved excisional capacity, but does require an intact host capacity for genetic recombination. No effects on host cell growth or postirradiation lag were observed. A proposed mechanism of action is described.
Purification and Properties of Proteolytic Enzymes from Thermophilic Actinomycetes
Authors: Desai A. J. , Dhala S. A.
Published: January 2020

The enzymes isolated from two selected cultures of thermophilic actinomycetes—
Thermomonospora fusca
(A 29) and
Thermoactinomyces vulgaris
(A 60)—possess proteolytic activity. The enzymes were purified more than 35- to 40-fold and showed three bands each upon cellulose acetate electrophoresis at several
p
H values. Based upon Sephadex gel filtration, molecular weights of 21,500 and 23,800 were calculated for the active peaks of the enzymes. The purified enzymes lysed heat-killed cells of gram-positive and gram-negative bacteria, mycobacteria, and fungi and also hydrolyzed casein. The enzymes were most active between a temperature range of 60 and 70 C and
p
H 8.0 and 9.0, and were significantly inhibited by potassium permanganate, potassium ferricyanide, and iodine.
Biosynthesis of Amino Sugars by
Pseudomonas saccharophila
Authors: Shuster C. W. , Betts June
Published: January 2020

Pseudomonas saccharophila
growing on specifically labeled glucose incorporated isotope into cell wall glucosamine and muramic acid with less than 5% randomization of carbons. Glucosamine contained isotope in both the 1 and 6 positions when cells were grown on either galactose-
6
-
14
C
or gluconate-
6
-
14
C
. With galactose-
1
-
14
C
, only muramic acid was labeled. Specific activities of the carboxyl group of muramic acid obtained from the glucose-grown cells did not indicate whether the origin of the side chain of muramic acid is pyruvate or phosphoenolpyruvate. However, the high specific activity obtained from galactose-
1
-
14
C
suggested that induced cells preferentially incorporate C-1 of galactose into the side chain of muramic acid. Addition of unlabeled glucosamine to growing cultures repressed incorporation of substrate isotope into glucosamine, but muramic acid contained activity in the lactyl side chain.
Inducible Synthesis of β-Galactosidase in Disrupted Spheroplast of
Escherichia coli
Authors: Maruo B. , Seto H. , Nagata Y.
Published: January 2020

A membrane preparation obtained from osmotic lysate of spheroplasts of
Escherichia coli
cells showed an activity of synthesizing β-galactosidase which was dependent upon oxidative phosphorylation. The synthesis was inhibited by the addition of actinomycin D or of chloramphenicol. The β-galactosidase synthesized in the membrane preparation was completely released into the medium, while that synthesized in the spheroplasts and intact cells remained within the cells. The minimum concentration of the inducer, methyl-β-
d
-thiogalactoside, required for the induction of β-galactosidase was 5 × 10
−5
m
for intact cells, 3 × 10
−4
m
for spheroplasts and 1 × 10
−3
m
for membrane preparation. Incorporation of labeled glucose into insoluble components in membrane preparation was extremely low compared with that in intact cells or in spheroplasts. Based on these and other observations, the nature of this membrane preparation is discussed in relation to the structure of
E. coli
cells.
Factors Influencing In Vitro Skin Permeability Factor Production byVibrio cholerae
Authors: Richardson Stephen H.
Published: January 2020

The development of a new semisynthetic medium which stimulates in vitro production of the skin permeability factor (PF) byVibrio choleraeis described. The effects ofpH, aeration, temperature, and length of incubation on PF formation or release in strain 569B and several other strains, or both, are compared. Data are presented which show that maximal PF accumulation occurs during a transitional period of growth joining the exponential and stationary phases of the growth cycle. PF elaboration is completed well ahead of any visible signs of lysis in the culture and the PF activity appears to be proportional to the length of the linear growth phase. Possible mechanisms of toxigenicity and the nature of PF are discussed.
Mechanism of Action of the Antifungal Antibiotic Pyrrolnitrin
Authors: Tripathi R. K. , Gottlieb David
Published: January 2020

Pyrrolnitrin at 10 μg/ml inhibited the growth of
Saccharomyces cerevisiae, Penicillium atrovenetum
, and
P. oxalicum
. The primary site of action of pyrrolnitrin on
S. cerevisiae
was the terminal electron transport system between succinate or reduced nicotinamide adenine dinucleotide (NADH) and coenzyme Q. At growth inhibitory concentrations, pyrrolnitrin inhibited endogenous and exogenous respiration immediately after its addition to the system. In mitochondrial preparations, the antibiotic inhibited succinate oxidase, NADH oxidase, succinate-cytochrome
c
reductase, NADH-cytochrome
c
reductase, and succinate-coenzyme Q
6
reductase. In addition, pyrrolnitrin inhibited the antimycin-insensitive reduction of dichlorophenolindophenol and of the tetrazolium dye 2,2′-di-
p
-nitrophenyl-(3,3′-dimethoxy-4,4′-bi-phenylene)5,5′-diphenylditetrazolium. The reduction of another tetrazolium dye, 2-
p
-iodophenyl-3-
p
-nitrophenyl-5-phenyltetrazolium chloride, that was antimycin-sensitive, was also inhibited by pyrrolnitrin. The antibiotic had no effect on the activity of cytochrome oxidase, and it did not appear to bind with flavine adenine dinucleotide, the coenzyme of succinic dehydrogenase. In whole cells of
S. cerevisiae
, pyrrolnitrin inhibited the incorporation of
14
C-glucose into nucleic acids and proteins. It also inhibited the incorporation of
14
C-uracil,
3
H-thymidine, and
14
C-amino acids into ribonucleic acid, deoxyribonucleic acid, and protein, respectively. The in vitro protein synthesis in
Rhizoctonia solani
and
Escherichia coli
was not affected by pyrrolnitrin. Pyrrolnitrin also inhibited the uptake of radioactive tracers, but there was no general damage to the cell membranes that would result in an increased leakage of cell metabolites. Apparently, pyrrolnitrin inhibits fungal growth by inhibiting the respiratory electron transport system.
Mutants Affecting Thymidine Metabolism in
Neurospora crassa
Authors: Williams Larry G. , Mitchell H. K.
Published: January 2020

When
14
C-thymidine labeled only in the ring is administered to
Neurospora crassa
, the majority of the recovered label is found in the ribonucleic acid (RNA). Three mutants were isolated in which different steps are blocked in the pathway that converts the pyrimidine ring of thymidine to an RNA precursor. Evidence from genetic, nutritional, and accumulation studies with the three mutants shows the pathway to proceed as follows: thymidine → thymine → 5-hydroxymethyluracil → 5-formyluracil → uracil → uridylic acid. A mutant strain in which the thymidine to thymine conversion is blocked is unable to metabolize thymidine appreciably by any route, including entry into nucleic acids. This suggests that
Neurospora
lacks a thymidine phosphorylating enzyme. A second mutation blocks the pathway at the 5-hydroxymethyluracil to 5-formyluracil step, whereas a third prevents utilization of uracil and all compounds preceding it in the pathway. The mutant isolation procedures yielded three other classes of mutations which are proposed to be affecting, respectively, regulation of the thymidine degradative pathway, transport of pyrimidine free bases, and transport of pyrimidine nucleosides.
Externally Suppressible Frameshift Mutant of
Salmonella typhimurium
Authors: Yourno Joseph , Barr Donald , Tanemura Shegeji
Published: January 2020

Prototrophic revertants of ICR-191A-induced frameshift mutant
hisD3018
have been induced spontaneously by ICR-191A and
N
-methyl-
N′
-nitro-
N
-nitrosoguanidine (NG) treatment. In each case two genetically distinct prototroph classes were differentiated by transducibility into
his
deletion recipients: (i) transducible, generally fast-growing revertants within the
hisD
gene producing from 10 to 100% of normal amounts of histidinol dehydrogenase and (ii) nontransducible slow-growing prototrophs with very low levels of enzyme activity of which at least some arose by external suppression. These nontransducible revertants, whether arising spontaneously or in the presence of ICR-191A or NG, contain histidinol dehydrogenase which is electrophoretically similar to the wild-type enzyme.
Wax D Fraction of an Unclassified
Mycobacterium
Strain
Authors: Sato Hirosi , Motomiya Masakichi , Fukushi Kazue , Fujimoto Masako , Oka Sutemi
Published: January 2020

Wax D prepared from the P-6 strain of the scotochromogenic species of
Mycobacterium scrofulaceum
constituted 0.3% of the dry bacilli. In the acid hydrolysates, alanine, glutamic acid, glycine, and mesodiaminopimelic acid were found as amino acid constituents. Mannose, galactose, and glucosamine were detected by paper chromatography. However, arabinose could not be detected. The quantity of hexosamine was 0.2 to 0.3%. Wax D of P-6 was found to be adjuvant-active, as revealed by a positive corneal reaction. The antigenicity of wax D of P-6 was shown by the agglutination reaction between the suspension of wax D and the anti-wax D antiserum. Periodate oxidation of the hydrosoluble portion reduced the inhibitory effect of the hydrosoluble portion on agglutination of the suspension of wax D. The light fraction of wax D had a peptide portion consisting of alanine, glutamic acid, glycine, and diaminopimelic acid and was found to be adjuvant-active in an amount of 1,000 μg.
Mycobacterial Polysaccharides II. Comparison of Polysaccharides from Strains of Four Species of Mycobacteria
Authors: Birnbaum Susan E. , Affronti Lewis F.
Published: January 2020

Evidence from chemical and serological studies indicates that a cellular heteropolysaccharide, also found in lipid extracts and culture filtrate, is present as a group antigen in
Mycobacterium tuberculosis
H37Ra and in other strains of mycobacteria representing
M. kansasii
, scotochromogenic and Battey strains. Polysaccharides from the four strains contain the same main sugars, arabinose, and galactose, as revealed by thin-layer chromatography and spectrophotometric studies. In Ouchterlony gel diffusions, bands of identity are produced between the polysaccharides by using rabbit antiserum prepared against any of the four mycobacteria. Immune adsorption studies also confirm the presence of identical antigenic determinant groups. In skin tests with tuberculopolysaccharide I, a skin reaction of about equal size was elicited in guinea pigs sensitized with either
M. tuberculosis
H37Ra or heterologous mycobacterial antigens in Freund's incomplete adjuvant. In animals sensitized with
M. tuberculosis
H37Ra, skin tests with both homologous and heterologous polysaccharides elicited similar responses.
Surface Localization of
Escherichia coli
5′-Nucleotidase by Electron Microscopy
Authors: Nisonson I. , Tannenbaum M. , Neu H. C.
Published: January 2020

The 5′-nucleotidase of
Escherichia coli
was shown to be located at the cell wall surface by histochemical techniques utilizing the deposition of inorganic phosphate. Penetration of the 5′-nucleotidase in the periplasmic space was seen only in cells treated with ethylenediaminetetraacetic acid (EDTA)-tris(hydroxymethyl)aminomethane (Tris). The 3′-nucleotidase of
E. coli
was also found to have a surface location, and periplasmic precipitation of inorganic phosphate was seen only after EDTA-Tris-sucrose exposure.
Regulation of the
meta
Cleavage Pathway for Benzoate Oxidation by
Pseudomonas putida
Authors: Feist Carol F. , Hegeman G. D.
Published: January 2020

Catechol or 2-hydroxymuconic semialdehyde cannot participate as functional inducers of the
meta
pathway for benzoate metabolism in
Pseudomonas putida
. Induction of the first two enzymes of the pathway must be mediated by benzoate, or its analogues, as primary substrate.
Characterization of the Biotin Transport System in
Saccharomyces cerevisiae
Authors: Rogers Thomas O. , Lichstein Herman C.
Published: January 2020

The characteristics of the biotin transport mechanism of
Saccharomyces cerevisiae
were investigated in nonproliferating cells. Microbiological and radioisotope assays were employed to measure biotin uptake. The vitamin existed intracellularly in both free and bound forms. Free biotin was extracted by boiling water. Chromatography of the free extract showed it to consist entirely of
d
-biotin. Cellular bound biotin was released by treating cells with 6
n
H
2
SO
4
. The rate of biotin uptake was linear with time for 10 min, reaching a maximum at about 20 min followed by a gradual loss of accumulated free vitamin from the cells. Biotin was not degraded or converted to vitamers during uptake. Transport was temperature- and
p
H-dependent, optimum conditions for uptake being 30 C and
p
H 4.0. Glucose markedly stimulated biotin transport. In its presence, large intracellular free-biotin concentration gradients were established. Iodoacetate inhibited the glucose stimulation of biotin uptake. The rate of vitamin transport increased in a linear fashion with increasing cell mass. The transport system was saturated with increasing concentrations of the vitamin. The apparent
K
m
for uptake was 3.23 × 10
−7
m
. Uptake of radioactive biotin was inhibited by unlabeled biotin and a number of analogues including homobiotin, desthiobiotin, oxybiotin, norbiotin, and biotin sulfone. Proline, hydroxyproline, and 7,8-diaminopelargonic acid did not inhibit uptake. Unlabeled biotin and desthiobiotin exchanged with accumulated intracellular
14
C-biotin, whereas hydroxyproline did not.
Regulatory Role of Adenine Nucleotides in the Biosynthesis of Guanosine 5′-Monophosphate
Authors: Nijkamp H. J. J.
Published: January 2020

Derepression of the synthesis of inosine 5′-monophosphate (IMP) dehydrogenase and of xanthosine 5′-monophosphate (XMP) aminase in
pur
mutants of
Escherichia coli
which are blocked in the biosynthesis of adenine nucleotides and guanine nucleotides differs in two ways from derepression in
pur
mutants blocked exclusively in the biosynthesis of guanine nucleotides. (i) The maximal derepression is lower, and (ii) a sharp decrease in the specific activities of AMP dehydrogenase and XMP aminase occurs, following maximal derepression. From the in vivo and in vitro experiments described, it is shown that the lack of adenine nucleotides in derepressed
pur
mutants blocked in the biosynthesis of adenine and guanine nucleotides is responsible for these two phenomena. The adenine nucleotides are shown to play an important regulatory role in the biosynthesis of guanosine 5′-monophosphate (GMP). (i) They induce the syntheses of IMP dehydrogenase and XMP aminase. (The mechanism of induction may involve the expression of the
gua
operon.) (ii) They appear to have an activating function in IMP dehydrogenase and XMP aminase activity. The physiological importance of these regulatory characteristics of adenine nucleotides in the biosynthesis of GMP is discussed.
Polarity in Gene
araB
of the
l
-Arabinose Operon in
Escherichia coli
B/r
Authors: Sheppard David E. , Walker Derinda A.
Published: January 2020

A series of mutations are described which map in the
araB
gene of the
l
-arabinose operon and exert a polar effect on gene
araA
, the structural gene for the
l
-arabinose isomerase. Ten of the 20
araB
point mutants examined exhibited absolute polarity and may represent insertions of genetic material into the
araB
gene. The remaining 10 point mutants exhibit strong polarity (less than 10% of the normal wild-type inducible level of isomerase) and may represent a class of externally suppressible polar mutations other than
amber
or
ochre
. Seven of the 12
araB
deletion mutants examined, or 58%, exhibit polarity, suggesting that a shift in the reading frame has been generated in the polycistronic message for the
l
-arabinose operon. The remaining, presumably in-phase, deletion mutants exhibit hyperinducible levels of isomerase, an effect that is eliminated when an
araB
+
gene is introduced in the
trans
position. The hyperinducibility effect is discussed in terms of a model for self-catabolite repression, originally proposed by Katz and Englesberg.
Purification and Properties of Staphylococcal Beta Hemolysin II. Purification of Beta Hemolysin
Authors: Haque Riaz-Ul , Baldwin Jack N.
Published: January 2020

Staphylococcal beta hemolysin from the 681 strain of
Staphylococcus aureus
grown in a Heart Infusion dialysate semisolid medium under 10% carbon dioxide was obtained in an immunoelectrophoretically pure form by a combination of procedures of precipitation with 2 volumes of acetone followed by chromatography on diethylaminoethyl cellulose at
p
H 6.0. The acetone precipitation procedure did not show any deleterious effect on the hemolytic activity of the beta hemolysin unless the precipitate was left in contact with the acetone for at least 4 hr. The crude preparations contained two types of beta hemolysin. One of these represented the major portion of the total activity of beta hemolysin and behaved as a cation. The other represented a minor (1/5,000) portion of the total beta hemolysin activity and behaved as an anion. These active principles were designated as cationic and anionic beta hemolysins, respectively. An unexpected increase in the total beta hemolysin activity of the crude preparations was noted when these were concentrated by dialysis against polyethylene glycol (20
m
). This effect was probably due to polyethylene glycol. A further unexpected increase in the titer of the acetone-precipitated preparations occurred when these were lyophilized. The reason for this incremental increase is not known. It may be due to fragmentation of the beta hemolysin.
Extracellular Deoxyribonuclease Production by Yeasts
Authors: Cazin John , Kozel Thomas R. , Lupan David M. , Burt Wayne R.
Published: January 2020

A total of 20 genera of yeasts and yeastlike organisms were tested for their ability to produce an extracellular deoxyribonuclease. Results indicate that ability to produce the enzyme appears to be a specific characteristic of the three genera
Rhodotorula, Cryptococcus
, and
Tremella
. A single strain of
Endomycopsis fibuligera
was also shown to be positive for the enzyme. In comparing the ability of the organisms to excrete extracellular deoxyribonuclease with their ability to produce urease, a surprisingly close correlation was found. With the exception of
Lipomyces starkeyi
, all the organisms which were deoxyribonuclease-negative were also urease-negative. Of those organisms which were deoxyribonuclease-positive, only
E. fibuligera
was urease-negative. The ability of cryptococci to produce extracellular deoxyribonuclease is discussed in relation to the implication which this finding may have for the taxonomy and phylogeny of the genus.
Isolation and Characterization of Host-Independent Bdellovibrios
Authors: Seidler Ramon J. , Starr Mortimer P.
Published: January 2020

A reliable method has been developed for the isolation of host-independent (H-I; i.e., “saprophytic”) strains of
Bdellovibrio
from host-dependent (H-D; i.e., “parasitic”) cultures. The technique involves growing streptomycin-resistant (Sm
r
) H-D cultures on streptomycin-susceptible (Sm
8
) host cells. A lysate containing large numbers of the Sm
r
H-D cells and some remaining Sm
8
host cells is transferred to a selection medium which contains the antibiotic. The Sm
8
host cells in the lysate are killed, and the Sm
r
H-I strains develop in broth within 3 to 6 days. By use of this method, it has been possible to isolate H-I strains from 16 different H-D
Bdellovibrio
strains studied. The frequency of occurrence of host independence is in the range of one H-I colony per 10
6
to 10
7
plaque-forming units of H-D bdellovibrios. The H-I cultures are nonfermentative, do not reduce nitrate, are strongly proteolytic, are oxidase-positive, and do not utilize 14 different carbon compounds as sources of energy for growth. Most H-I cultures are catalase-positive upon initial isolation from H-D lysates, but some cultures lose this enzyme upon subsequent transfers through host-free media. Most H-I bdellovibrios are pleomorphic, consisting of vibrio- to spiral-shaped cells typically measuring 0.3 to 0.4 μm in width and 1 to 10 μm in length. All H-I bdellovibrios have a cytochrome
a
and
c
component (H-I A3.12 differs from the other strains in the location of the peaks of the cytochrome spectrum). All are sensitive to oxytetracycline and (except for strain H-I A3.12) to the vibriostatic pteridine 0/129; most bdellovibrios, except for H-I A3.12, are generally uniformly resistant or susceptible to a given antibiotic.
Bdellovibrio
and
Vibrio
spp. have common cytochrome difference spectra and susceptibilities to oxytetracycline and to the vibriostatic pteridine 0/129. All H-I bdellovibrios examined produce an exocellular protease which digests heat-killed host cells. Bdellovibrios possessing predatory and bacteriolytic properties could be reselected from H-I bdellovibrio cultures growing in the presence of living host cells. Attempts to select for bacteriolytic isolates from
Vibrio
and
Spirillum
spp. were unsuccessul.
Lipid Synthesis by Isolated
Chlamydia psittaci
Authors: Gaugler Robert W. , Neptune Edgar M. , Adams George M. , Sallee Terry L. , Weiss Emilio , Wilson Noralee N.
Published: January 2020

The isolated cells of the host-dependent meningopneumonitis agent,
Chlamydia psittaci
, were shown to incorporate radioactive carbon from aspartate, isoleucine, and glucose-6-phosphate into cell lipids. The nature of this incorporation was investigated. Radioactivity was found only in the fatty acids and primarily in the phosphatidyl ethanolamine, and, to a lesser extent, in the phosphatidyl choline fractions. Branched-chain fatty acids, not found in host lipid, were shown to constitute a large proportion of the fatty acid content of phosphatidyl ethanolamine. The reasons why only fatty acid synthesis took place under the conditions of our experiments with isolated meningopneumonitis agent cells remain obscure.
Catabolite Inhibition: a General Phenomenon in the Control of Carbohydrate Utilization
Authors: McGinnis James F. , Paigen Kenneth
Published: January 2020

When
Escherichia coli
is grown in synthetic medium with radioactive galactose or lactose as the carbon source, the addition of glucose rapidly inhibited utilization of the radioactive substrate, whether the formation of
14
CO
2
or acid-insoluble products was measured. The inhibition was reversed after the removal of glucose. Experiments with mutants blocked in subsequent steps of galactose and lactose metabolism demonstrated that the inhibition occurs prior to the formation of the first metabolic product. The utilization of a variety of sugars, including maltose, lactose, mannose, galactose,
l
-arabinose, xylose, and glycerol was inhibited by glucose. Of a number of carbohydrates tested as potential inhibitors, only glucose and, to a lesser extent, glucose-6-phosphate (G-6-P) were capable of inhibiting the utilization of all of the substrates. Glucose did not inhibit G-6-P utilization but G-6-P inhibited glucose utilization. With all substrates, except glycerol, there was a delay before the onset of inhibition by G-6-P. We conclude that
E. coli
has a general regulatory mechanism, termed catabolite inhibition, which controls the activity of early reactions in carbohydrate metabolism, allowing certain substrates to be utilized preferentially.
Membrane Adenosine Triphosphatase of
Escherichia coli:
Activation by Calcium Ion and Inhibition by Monovalent Cations
Authors: Evans Doyle J.
Published: January 2020

Membrane ghost preparations of
Escherichia coli
K-12 obtained by osmotic lysis of lysozyme-induced spheroplasts were found to possess both Mg
++
- and Ca
++
-activated adenosine 5′-triphosphatase (ATPase, EC 3.6.1.3) activities. Maximal activities of 1.0 to 1.5 μmoles of orthophosphate released per min per mg of protein were obtained at
p
H 9.0 with a molar Mg
++
to adenosine 5′triphosphate (ATP) ratio of 2:5 and at
p
H 9.9 with a molar Ca
++
to ATP ratio of 1:5. These ATPase activities were not altered by ouabain, fluoride,
N
-ethylmaleimide, 2,4-dinitrophenol, cyanide, or dithionite, but were inhibited by low concentrations of azide,
p
-chloromercuribenzoate, and pentachlorophenol. Mg
++
ATPase was more susceptible to inhibition by azide than was Ca
++
ATPase. Fifty per cent inactivation of both activities was observed when membrane ghost preparations were preincubated at 66 C for 10 min. The Mg
++
and Ca
++
ATPase activities of these preparations were not additive, but did respond independently to inhibition by monovalent cations. Ca
++
ATPase was found to be very sensitive to inhibition by K
+
, Na
+
, Li
+
, Rb
+
, and Cs
+
; Mg
++
ATPase was relatively insensitive to these ions. One possible interpretation of the results presented in this paper is that the membrane of
E. coli
possesses an ATPase which is activated by either Mg
++
or Ca
++
and that activation by Ca
++
increases the susceptibility of this enzyme to inhibition by monovalent cations. Increased susceptibility of
E. coli
membrane ATPase to inhibition by monovalent cations such as Na
+
and K
+
as a consequence of Ca
++
activation could represent a regulatory mechanism.
Spore Fine Structure in
Clostridium cochlearium
Authors: Pope Leodocia , Rode L. J.
Published: January 2020

The fine structure of
Clostridium cochlearium
was examined by use of thin sections, negative stains, and carbon replicas. Particular attention was given to details of the sporulation process and to fine structure of the spores. Spore coat formation was well advanced before the first evidence of cortex formation was noted. Three distinct spore coats were detected, the outermost of which was composed of seven layers. In addition, the spores possessed tubular appendages of variable length attached to one end of the spore. These differed in a number of respects from those described for other clostridia.
Modified Substrates and Modified Products as Inducers of Carbohydrases
Authors: Reese E. T. , Lola J. E. , Parrish F. W.
Published: January 2020

Cellobiose and isomaltose are both inducers and repressors of cellulase and dextranase, respectively. The repression can be avoided by supplying the disaccharide slowly. This has been done by use of palmitate and acetate esters which are hydrolyzed by esterases of the growing organism to yield the inducer. Sucrase yields, also, are greatly increased (to 80 times) by substituting sucrose monopalmitate for sucrose in the culture medium.
Yersinia philomiragia sp. n., a New Member of the Pasteurella Group of Bacteria, Naturally Pathogenic for the Muskrat (Ondatra zibethica)
Authors: Jensen Wayne I. , Owen Cora R. , Jellison William L.
Published: January 2020

A bacterium experimentally pathogenic for muskrats (
Ondatra zibethica
), white mice, mountain voles (
Microtus montanus
), and deer mice (
Peromyscus maniculatus
) was isolated from the tissues of a sick muskrat captured on the Bear River Migratory Bird Refuge (Brigham City, Utah) and from four surface water samples collected within 15 miles of that point. In culture, the cells are chiefly coccoid, but in the tissues of muskrats and voles they resemble the bizarre forms of
Yersinia pestis
, except for their smaller size. The characteristics of the organism are described and the name
Yersinia philomiragia
sp. n. is proposed.
Catabolic Activities of
Neisseria meningitidis:
Utilization of Succinate
Authors: Weiss Emilio
Published: January 2020

When resting cells of
Neisseria meningitidis
group B were incubated with either succinate, fumarate, or malate, respiration and CO
2
production were not significantly stimulated. These dicarboxylic acids were readily utilized, however, when they were added in association with a combination of α-ketoglutarate and aspartate or with glucose or with glutamate. The amounts of these substrates required for exogenous succinate utilization were relatively large. Both the α-ketoglutarate–aspartate combination and glutamate greatly stimulated succinate uptake into the cells, but glutamate was far more effective than the α-ketoglutarate–aspartate combination in eliciting exogenous succinate utilization. This difference is explained on the basis of evidence reported in another article that succinate derived from the α-ketoglutarate-aspartate mixture is metabolized more rapidly—and thus more rapidly dilutes the specific activity of added succinate—than the succinate derived from glutamate.
Multiple Impairment of Glycolysis in
Veillonella alcalescens
Authors: Michaud R. N. , Delwiche E. A.
Published: January 2020

The property of glucose nonfermentation, characteristic of the genus
Veillonella
, was investigated in
V. alcalescens
C1, a strain of sheep rumen origin. Cell-free extracts as well as intact cells were incapable of glucose fermentation, thereby eliminating the possibility of nonpermeation. Assimilation of
14
C-glucose was not detectable. Of the 10 glycolytic enzymes, hexokinase, phosphoglyceromutase, and pyruvate kinase were not detectable. The other glycolytic enzymes were present.
Extrusion of Sodium and Hydrogen Ions as the Primary Process in Potassium Ion Accumulation by
Streptococcus faecalis
Authors: Harold F. M. , Baarda J. R. , Pavlasova E.
Published: January 2020

Glycolyzing cells of
Streptococcus faecalis
accumulate K
+
with concurrent extrusion of equivalent amounts of H
+
and Na
+
. An attempt was made to clarify the retionship between the movements of Na
+
and K
+
. Sodium was displaced from cells glycolyzing in the presence of ammonia, diethylamine, tris(hydroxymethyl)aminomethane, and other nitrogenous cations; by contrast, K
+
was completely retained. Accumulation of K
+
by heterologous exchange for Na
+
was not inhibited by antibiotics which facilitate diffusion of K
+
across the membrane, but was blocked by proton conductors. The results indicate that extrusion of Na
+
and H
+
from the cells is a primary, energy-linked process which generates an electrical potential (interior negative); K
+
accumulation occurs in response to this potential. Two mutants deficient in K
+
accumulation and retention were examined in terms of this model. One mutant is apparently defective in exchange of K
+
for H
+
. In the other mutant, exchange of K
+
for Na
+
is impaired.
Increase in Lytic Activity in Competent Cells of
Bacillus subtilis
After Uptake of Deoxyribonucleic Acid
Authors: Stewart Charles R. , Marmur Julius
Published: January 2020

Extractable lytic activity in competent cells of
Bacillus subtilis
168 was markedly increased after treatment with homologous or heterologous deoxyribonucleic acid (DNA). This increase was prevented by deoxyribonuclease, and did not occur with
B. subtilis
W23 or with noncompetent
B. subtilis
168 cells, neither of which take up DNA. Although the deoxyribonuclease-sensitive step in DNA uptake was completed within 10 min, the increase in lytic activity did not begin until more than 30 min after the addition of DNA. The increase was prevented by any of several antibiotics. These results are discussed in relation to the mechanisms for the uptake of transforming DNA and the lysis of transfected cells.