bluuebunny/crossref_metadata_2025 huggingface dataset:
Properties of a Purified Halophilic Malic Dehydrogenase
Authors: Holmes P. K. , Halvorson H. Orin
Published: January 2020

Holmes, P. K.
(University of Illinois, Urbana),
and H. Orin Halvorson
. Properties of a purified halophilic malic dehydrogenase. J. Bacteriol.
90:
316–326. 1965.—The malic dehydrogenase (MDH) from
Halobacterium salinarium
required high concentrations of monovalent ions for stability and activity. Studies of inactivation rates at different salt concentrations suggested that approximately 25% NaCl (w/v) is required to stabilize MDH. From 50 to 100% reactivation, depending on the salt concentration present during inactivation, could occur in 2.5 to 5
m
NaCl or KCl. The optimal salt concentration for activity of MDH was a function of the
p
H, and ranged from 1 to 3
m
NaCl or KCl. The effect of salt concentration on the
p
H-activity curves occurred chiefly below
p
H 7.0. Inactivation of MDH with heat or thiol reagents showed that the enzyme was more labile in the state induced by absence of salt. The activation of MDH by salts was attributed to a decreased rate of dissociation of MDH and reduced nicotinamide adenine dinucleotide (NADH
2
). The inactivation of the enzyme in the absence of salt could be largely prevented by the presence of NADH
2
. The
S
20.w
of MDH decreased threefold at low salt concentrations. The enzyme was assumed to be in its native compact configuration only in the presence of a high concentration of salt.
Enzymatic Deacylation of S
35
-Benzylpenicillin
Authors: Pruess David L. , Johnson Marvin J.
Published: January 2020

Pruess, David
L. (University of Wisconsin, Madison),
and Marvin J. Johnson
. Enzymatic deacylation of S
35
-benzylpenicillin. J. Bacteriol.
90:
380–383. 1965.—S
35
-benzylpenicillin, penicilloic acid, and penilloic acid were deacylated by cell suspensions of
Escherichia coli
and
Micrococcus roseus
. Both cultures deacylated penicillin most rapidly and penilloic acid least rapidly. The deacylase activity of
M. roseus
against penicilloic acid was cell-bound, probably requiring a metal ion for activity.
Transformation of Mycelial and Yeast Forms of
Paracoccidioides brasiliensis
in Cultures and in Experimental Inoculations
Authors: Carbonell Luis M. , Rodríguez Joaquín
Published: January 2020

Carbonell, Luis
M. (Instituto Venezolano de Investigaciones Científicas, Caracas, Venezuela),
and Joaquín Rodríguez
. Transformation of mycelial and yeast forms of
Paracoccidioides brasiliensis
in cultures and in experimental inoculations. J. Bacteriol.
90:
504–510. 1965.—Experimental transformations of mycelial to yeast and yeast to mycelial forms in culture, and mycelial to yeast forms in tissue, were studied. All the transitional forms that appeared in culture were also seen in tissue, but in fewer number. Most of the hyphae in culture were transformed into yeast, but only a few in tissue. Yeast appeared in testicle around the 3rd day after inoculation, but on the 10th day in subcutaneous tissue. Pathogenicity of mycelium was high, since yeast was found in almost all of the organs inoculated with mycelium. Histologically, an acute inflammation occurred first, owing to the inoculation of mycelium, followed by a giant-cell granuloma with abundant hyphae detritus. These giant cells almost disappeared about 10 days after inoculation, giving place to a second giant-cell granuloma with yeast forms.
Electron Microscopy of Cell Fusion in Conjugating
Hansenula wingei
Authors: Conti S. F. , Brock T. D.
Published: January 2020

Conti
, S. F. (Dartmouth Medical School, Hanover, N.H.),
and T. D. Brock
. Electron microscopy of cell fusion in conjugating
Hansenula wingei
. J. Bacteriol.
90:
524–533. 1965.—The heterothallic yeast
Hansenula wingei
is a favorable organism for the study of the process of cell fusion, since strong agglutination of cells of the two mating types ensures a high percentage of cell fusions. The initial agglutination reaction results in cell-wall deformation, so that the walls in the region of contact are tightly appressed over an extensive area. The fusion process is initiated when the walls of two cells elongate, and this elongation seems to be restricted to the region where the cells touch. Occasionally, one cell is seen to push in the wall of the other, but in many cases both cells elongate equally, as would be expected in an isogamous organism. The precise disposition of the elongating wall probably reflects the manner in which the cells initially become associated in the agglutinated cell clump. Soon after wall elongation begins, cell-wall fusion occurs along the margin of contact. Only after fusion is complete is the wall separating the two cells dissolved away. If wall dissolution begins at one edge of the conjugation tube, a flap is formed in which can be seen the remnants of the fused walls. Alternatively, dissolution can begin at the center of the conjugation tube, proceeding towards the outside. Conjugating cells are uninucleate, and the nuclei are large and frequently lobed or elongated. After the conjugation tube is formed, the nuclei migrate towards the center, and fusion occurs only over a small region where the nuclear membranes come in contact. After nuclear fusion, the first diploid bud forms from the conjugation tube and at right angles to the tube axis. The diploid nucleus then migrates into this bud. Frequently, in the later stages of conjugation, a large vacuole develops in each of the original cells. All of the above events will occur in a medium devoid of a nitrogen source and in which vegetative budding will not occur.
Assay for the Killing Properties of T2 Bacteriophage and Their “Ghosts”
Authors: Duckworth Donna H. , Bessman Maurice J.
Published: January 2020

Duckworth, Donna
H. (Johns Hopkins University, Baltimore, Md.),
and Maurice J. Bessman
. Assay for the killing properties of T2 bacteriophage and their “ghosts.” J. Bacteriol.
90:
724–728. 1965.—A procedure for the assay of bacteriophage and their “ghosts” which is based on their ability to kill cells is described. The method is derived from the well-known ability of phage and ghosts to prevent the induction of β-galactosidase. Conditions are described whereby a direct relationship is found between the decrease in β-galactosidase and the number of phage or ghosts present during the induction period. The number of phage measured by this method was found to be identical with the number of plaque-forming units found in a fresh lysate. The method has been used to follow the fate of ghosts under several conditions and to measure killer (but nonviable) particles in various preparations of phage.
Stimulation of
Nitrobacter agilis
by Biotin
Authors: Krulwich Terry A. , Funk Helen B.
Published: January 2020

Krulwich, Terry
A. (Goucher College, Baltimore, Md.),
and Helen B. Funk
. Stimulation of
Nitrobacter agilis
by biotin. J. Bacteriol.
90:
729–733. 1965.—Addition of biotin to nitrite-mineral medium greatly stimulated the autotrophic growth of four strains of
Nitrobacter agilis
. Comparisons of cultures of the organisms grown in parallel at 30 C in nitrite medium and in the medium supplemented with 150 mμg of biotin per ml showed that the vitamin promoted: (i) 2- to 4-fold greater rates of utilization of nitrite, and (ii) 100- to 1,000-fold greater populations of cells per milliliter. Avidin specifically inhibited the biotin stimulation of nitrite utilization at an avidin-biotin ratio of 133:1. Incubation of the four strains of
N. agilis
at 37 C imposed a requirement for biotin that could be met by daily addition of 150 mμg of the vitamin per ml of medium. The stimulatory effects of the vitamin at 30 C suggest that in
N. agilis
the synthesis of biotin is rate-limiting for growth.
Multiple-Tailed T4 Bacteriophage
Authors: Smith Kendall O. , Trousdale Melvin
Published: January 2020

Smith, Kendall
O. (Baylor University College of Medicine, Houston, Tex.), and
Melvin Trousdale
. Multiple-tailed T4 bacteriophage. J. Bacteriol.
90:
796–802. 1965.—T4 phage particles which appeared to have multiple-tails were observed. Experiments were designed to minimize the possibility that superimposed particles might account for this appearance. Double-tailed particles occurred at a frequency as high as 10%. Triple- and quadruple-tailed particles were extremely rare. All attempts to isolate pure lines of multiple-tailed phage have failed. Multiple-tailed phage particles were produced in highest frequency by
Escherichia coli
cells in the logarithmic growth phase which had been inoculated at a multiplicity of about 2.
Morphology, Antigenicity, and Nucleic Acid Content of the
Bacteroides
sp. Used in the Culture of
Entamoeba histolytica
Authors: Albach Richard A. , Shaffer James G. , Watson Robert H.
Published: January 2020

Albach, Richard
A. (Lutheran General Hospital, Park Ridge, Ill.),
James G. Shaffer, and Robert H. Watson
. Morphology, antigenicity, and nucleic acid content of the
Bacteroides
sp. used in the culture of
Entamoeba histolytica
. J. Bacteriol.
90:
1045–1053. 1965.—Certain changes in morphology, antigenicity, and nucleic acid content that occur in a culture of
Bacteroides
sp. in the presence of penicillin G in CLG medium are described. This “variant” is one of seven recovered in several laboratories, all of which are descendants of the original
Bacteroides
isolated by Shaffer and Frye. Penicillin-inhibited cells of this culture are currently being used in the routine propagation of
Entamoeba histolytica
in CLG medium. Evidence is presented for the loss of ability to react with antibody in these penicillin-inhibited bacteria in CLG medium, when studied by fluorescent-antibody techniques. The implications of the antigenic changes observed as they pertain to similar antigenic studies of the amoebas are discussed. A pronounced reduction in the ribonucleic acid (RNA) content of such penicillin-inhibited cells was also observed. The potential importance of the changes that occur in the RNA of these cells with respect to considerations of the growth requirements of the amoebas is also discussed.
Hypoferremia in Mice and Its Application to the Bioassay of Endotoxin
Authors: Baker Phillip J. , Wilson J. B.
Published: January 2020

Baker, Phillip
J. (University of Wisconsin, Madison),
and J. B. Wilson
. Hypoferremia in mice and its application to the bioassay of endotoxin. J. Bacteriol.
90:
903–910. 1965.—The ability of endotoxin to induce hypoferremia in mice was used for the bioassay of endotoxin. A marked depression in the serum-iron levels of mice occurred 12 hr after the intraperitoneal injection of 0.01 to 100 μg of
Escherichia coli
endotoxin; similar results were obtained with 1.0 to 100 μg of
Brucella abortus
endotoxin. This biological response to endotoxin appeared to be specific, reproducible, and dose-dependent. As heat-killed cells of
B. abortus
and
E. coli
were also able to induce hypoferremia, this bioassay could be employed for the determination of the endotoxin content of killed-cell preparations. Treatment of endotoxin by acid hydrolysis, acetylation, or pyridine-formic acid greatly diminished the hypoferremic response as well as its lethality for mice. Pretreatment of mice with Thorotrast had little effect upon the ability of endotoxin to induce hypoferremia; however, a stimulation of the activity of the reticuloendothelial system (RES) by treatment of mice with triolein markedly reduced the ability of endotoxin to induce hypoferremia. The relationship between the hypoferremic response to endotoxin and alterations in the activity of the RES are discussed.
Damage to
Streptococcus Lactis
Resulting from Growth at Low
p
H
Authors: Harvey R. J.
Published: January 2020

Harvey
, R. J. (The Dairy Research Institute, Palmerston North, New Zealand). Damage to
Streptococcus lactis
resulting from growth at low
p
H. J. Bacteriol.
90:
1330–1336. 1965.—Growth of
Streptococcus lactis
below
p
H 5.0 results in damage to the cells. A period of growth below
p
H 5.0 is required before this damage is expressed, and a period of growth above
p
H 5.0 is required to correct the damage. Part of the damage consists of a reduction in the specific activities of a number of enzymes. At the same time, the differential rate of total protein synthesis is unchanged. During recovery from growth at low
p
H, the enzymes subject to damage are formed at a differential rate which is higher than normal until the normal specific activities are restored. The growth rate characteristic of the new
p
H is then resumed. The results are consistent with either of two mechanisms of damage. Growth at low
p
H could result either in direct inactivation of a number of enzymes, or in loss of control of the differential rates of synthesis of individual enzymes.
Mitochondrial Fatty Acid Oxidation and Susceptibility to Endotoxin in Acute Liver Injury
Authors: Farrar W. Edmund , Corwin Laurence M. , Kent Thomas H.
Published: January 2020

Farrar, W. Edmund, Jr.
(Walter Reed Army Institute of Research, Washington, D.C.),
Laurence M. Corwin, and Thomas H. Kent
. Mitochondrial fatty acid oxidation and susceptibility to endotoxin in acute liver injury. J. Bacteriol.
90:
1365–1372. 1965.—Acute liver injury was produced in guinea pigs with three chemically unrelated hepatotoxins: CCl
4
, allyl alcohol, and
dl
-ethionine. The effects of these agents on liver morphology, susceptibility of animals to
Escherichia coli
endotoxin, endotoxin-inactivating ability of tissue homogenates, and substrate oxidation by liver mitochondria were studied. CCl
4
markedly reduced oxidation of all substrates studied except succinate, impaired the ability of liver homogenates to detoxify endotoxin in vitro, and increased the susceptibility of animals to the lethal effect of endotoxin by 150-fold. Allyl alcohol produced a severe morphological lesion in the liver but did not impair fatty acid oxidation by mitochondria, diminish endotoxin detoxification by liver homogenates, or greatly enhance susceptibility of the animals to endotoxin. Ethionine showed an effect intermediate between the other two agents. These findings are consistent with the hypothesis that the liver performs an important function in the detoxification of endotoxin by the oxidation of fatty acid residues in the endotoxin molecule.
Effects of Toluene on
Escherichia coli
Authors: Jackson Robert W. , DeMoss J. A.
Published: January 2020

Jackson, Robert
W. (University of California, San Diego, La Jolla),
and J. A. DeMoss
. Effects of toluene on
Escherichia coli
. J. Bacteriol.
90:
1420–1425. 1965.—When toluene is added at appropriate levels to exponentially growing cultures of
Escherichia coli
, a time-dependent loss of turbidity is observed which is concurrent with a loss of material to the medium and with unmasking of β-galactosidase. In addition, the galactoside permease system is totally destroyed. Electron micrographs confirm the indications that the cells are not being lysed by toluene, although the cytoplasm collapses to the interior of the cell. Included in the material lost from the cell after toluene treatment is 85% of the total ribonucleic acid (RNA), the principal source of which appears to be the ribosomes. The loss of RNA is temperature-dependent. Protein is also lost to the medium as a function of both temperature and available toluene. Up to 25% of the total protein is found in the medium, the precise amount depending on the level of toluene employed. Zone centrifugation studies of extracts from treated cells indicate that toluene elicits a rapid disaggregation of ribosomes that is terminated, at any stage, by disruption of the cells. The disaggregation is temperature-dependent and does not occur at 4 C. It appears to be distinct from the actual degradation of ribosomal RNA and is accompanied by an accumulation of small particles during the initial phases of treatment at 21 C. Toluene added to crude extracts of normal
E. coli
cells is unable to cause detectable ribosome destruction.
In Vitro Inhibition of Diphtheria Toxin Action by Ammonium Salts and Amines
Authors: Kim K. , Groman N. B.
Published: January 2020

Kim, K
. (University of Washington, Seattle),
and N. B. Groman
. In vitro inhibition of diphtheria toxin action by ammonium salts and amines. J. Bacteriol.
90:
1552–1556. 1965.—An inhibitor for diphtheria toxin action on HeLa cells was demonstrated in the growth supernatant fractions of both toxinogenic and nontoxinogenic strains of
Corynebacterium diphtheriae
and in the Mueller and Miller medium in which these organisms were grown. The inhibitor in the growth supernatant fractions of the nontoxinogenic strain was dialyzable, stable to autoclaving, and stable on storage in the refrigerator for a period of many months, but was destroyed by ashing. When the components of Mueller and Miller medium were analyzed, only the Casamino Acids proved inhibitory. Further study with artificial mixtures of amino acids revealed that glutamine alone inhibited toxin. It was subsequently shown that ammonium salts and the aliphatic amines, glycamine and prolamine, could also function as inhibitors. Histamine and 16 amino acids tested individually were ineffective. The effectiveness of the amines and the ineffectiveness of sodium or potassium ions indicates that there is a specific requirement for inhibition.
Reciprocal Recombination of Chromosome and F-Merogenote in
Escherichia coli
Authors: Herman Robert K.
Published: January 2020

Herman, Robert
K. (Lawrence University, Appleton, Wis.). Reciprocal recombination of chromosome and F-merogenote in
Escherichia coli
. J. Bacteriol.
90:
1664–1668. 1965.—Mitotic recombination of an F-merogenote with the bacterial chromosome was observed under conditions where both recombinant episome and reciprocally recombinant chromosome, if formed and if passed on to the same progeny, could be detected. Recombinant strains selected on the basis of having a recombinant F-merogenote were found frequently to contain a recombinant chromosome of the reciprocal type.
Use of Dialyzing Culture Technique for High Yield of
Mycoplasma
Authors: Pollock Mary E.
Published: January 2020

Pollock, Mary
E. (University of Minnesota, Minneapolis). Use of dialyzing culture technique for high yield of
Mycoplasma
. J. Bacteriol.
90:
1682–1685. 1965.—The saprophytic pleuropneumonia-like organism,
Mycoplasma laidlawii
, type A, was cultivated within a dialyzing membrane suspended in a reservoir of uninoculated medium. Generation time was not decreased by this method, but the period of active growth was prolonged, and the final yield was 10-fold that attained by the usual cultural methods. A defined mixture, which alone would not support growth of
Mycoplasma
, could replace the complex soy peptone-yeast extract medium in the inner membrane vessel of the dialyzing culture flask with no decrease in growth rate or yield.
Isolation and Characterization of Filterable Marine Bacteria
Authors: Anderson J. I. W. , Heffernan W. P.
Published: January 2020

Anderson
, J. I. W. (Northeast Shellfish Sanitation Research Center, Narragansett, R.I.),
and W. P. Heffernan
. Isolation and characterization of filterable marine bacteria. J. Bacteriol
90:
1713–1718. 1965.—By a process of double filtration of seawater, first through a membrane filter with a pore diameter of 0.45 μ and then through a membrane filter with a pore diameter of 0.22 μ, it was possible to isolate on the surface of the latter membrane a group of marine organisms not usually encountered by conventional techniques of pour plates or one-stage filtration. Many of the isolates could not be identified, but the largest single group belonged to the genus
Spirillum
; other isolates were placed in the genera
Leucothrix, Flavobacterium, Cytophaga
, and
Vibrio
. A group of four organisms which was not identified was characterized by the formation of large, club-shaped cells, 20 to 30 μ long. Of the 25 strains studied in detail, 22 required seawater for growth and 8 retained their filterable property after cultivation. No filterable bacteria were isolated from terrestrial samples.
Morphology of
Mycoplasma laidlawii
Type A II. Effect of Glucose on Growth and Cellular Morphology
Authors: Anderson D. L. , Pollock M. E. , Brower L. F.
Published: January 2020

Anderson
, D. L. (University of Minnesota, Minneapolis), M. E.
Pollock, and L. F. Brower
. Morphology of
Mycoplasma laidlawii
type A. II. Effect of glucose on growth and cellular morphology. J. Bacteriol.
90:
1768–1777. 1965.—Cells of
Mycoplasma laidlawii
A grown in soy peptone-yeast extract (SP-YE) broth reached higher maximal titers than cells grown in SP-YE supplemented with 0.2% glucose, and remained viable longer than glucose-grown cells. Moreover, addition of glucose to SP-YE markedly affected the morphological developmental sequence of the organism. The diameter of glucose-grown cells at 28 to 40 hr was often two to four times that of cells grown without glucose; these large glucose-grown cells deteriorated progressively, and presumably liberated 0.1- to 0.25-μ small bodies. In contrast, pleomorphic 22- to 28-hr cells grown in SP-YE without glucose gave rise to uniform bodies 0.5 to 1.0 μ in diameter; limited numbers of 0.1- to 0.25-μ small bodies were also liberated in nonglucose cultures after 45 to 64 hr. Electron-microscopic counts of 16- to 64-hr cultures agreed well with counts of colony-forming units (CFU) when organisms larger than 0.25 μ were included in the microscopic counts. Small bodies, 0.1 to 0.25 μ in diameter, apparently did not contribute substantially to numbers of CFU. Droplet patterns of cells grown in Arginine Assay Medium and L15 Tissue Culture Medium were cleaner than patterns of cells grown in SP-YE.
Changes in Fungi with Age II. Respiration and Respiratory Enzymes of
Rhizoctonia solani
and
Sclerotium bataticola
Authors: Van Etten James L. , Molitoris H. Peter , Gottlieb David
Published: January 2020

Van Etten, James
L. (University of Illinois, Urbana), H.
Peter Molitoris, and David Gottlieb
. Changes in fungi with age. II. Respiration and respiratory enzymes of
Rhizoctonia solani
and
Sclerotium bataticola
. J. Bacteriol.
91:
169–175. 1966.—The rate of respiration of
Rhizoctonia solani
and
Sclerotium bataticola
decreased with age. This decrease in respiratory rate might be produced by a decrease in the specific activity of one or more enzymes involved in carbohydrate metabolism. Specific activities in cell-free extracts were measured for most of the enzymes in the hexose monophosphate shunt, Embden-Meyerhof-Parnas pathway, tricarboxylic acid cycle, and terminal electron-transport system. In addition, glucose oxidase, isocitritase, and malic enzyme were measured. In
R. solani
, increases in activity with age occurred for hexokinase, α-glycerolphosphate dehydrogenase, malic dehydrogenase, and cytochrome oxidase. Decreases occurred for phosphohexokinase, aconitase, nicotinamide adenine dinucleotide-specific isocitric dehydrogenase, reduced nicotinamide adenine dinucleotide oxidase, and at least one of the enzymes between 3-phosphoglycerate and pyruvate. In
S. bataticola
, increases in activity with age were observed for phosphohexokinase, pyruvic dehydrogenase, fumarase, malic dehydrogenase, and malic enzyme, whereas none of the enzymes decreased. The specific activities of the remaining enzymes did not change with age in either fungus.
Inhibition of Mengo Virus by Interferon
Authors: Gauntt Charles J. , Lockart Royce Z.
Published: January 2020

Gauntt, Charles
J. (The University of Texas, Austin),
and Royce Z. Lockart, Jr.
Inhibition of Mengo virus by interferon. J. Bacteriol.
91:
176–182. 1966.—The inhibition of Mengo virus replication in L cells resulting from interferon was studied quantitatively. Interferon was titrated on L cells with Western equine encephalomyelitis (WEE) virus as the challenge virus. One protective unit (PU) of interferon is the least amount of interferon which prevents cytopathic effects when a large multiplicity of WEE virus is added subsequent to overnight incubation with interferon. Ten PU of interferon reduced the yields of Mengo virus by about 90%. Larger doses of interferon, up to 220 PU, caused no further reduction in the amount of virus produced. Plaque formation by Mengo virus was also reduced in number by about 85 to 90%, but could not be further reduced. The plaques which formed on interferon-treated cells were reduced in size. We were unable to obtain a virus population with increased resistance to interferon action by use of five successive growth cycles in interferon-treated cultures. Analysis of the cell population for the proportion of cells able to act as infectious centers revealed that incubation of cells with 10 PU of interferon decreased the proportion of virus-yielding cells by 80%. The yield of virus per virus-producing cell was decreased by 40 to 60%. Despite the reduction in yields, plaques, and infectious centers resulting from interferon, all doses of interferon failed to prevent the complete destruction of the cells. Experiments with puromycin indicated that the cytopathic effects observed in L cells infected with Mengo virus required that a virus-directed protein be synthesized between 4 and 5 hr postinfection. The evidence suggested, therefore, that the Mengo virus genome was able to code for new protein synthesis in the absence of the production of infectious virus.
Specific Cell-Surface Alteration by Enteroviruses as Reflected by Viral-Attachment Interference
Authors: Crowell Richard L.
Published: January 2020

Crowell, Richard
L. (Hahnemann Medical College, Philadelphia, Pa.). Specific cell-surface alteration by enteroviruses as reflected by viral-attachment interference. J. Bacteriol.
91:
198–204. 1966.—Exposure of HeLa cells to high levels of coxsackievirus B3 produced cells which were refractory to attachment of coxsackievirus B1, whereas poliovirus T2 attached normally. Under similar conditions, poliovirus T2 was found to interfere with the attachment of poliovirus T1 to HeLa cells without affecting the attachment rate of coxsackievirus B3. The data confirm earlier findings that the receptor sites on HeLa cells, which bind members of group B coxsackieviruses, are distinct from those for polioviruses. Quantitatively, coxsackieviruses B1 and B3 were found to be mutually exclusive in the attachment interference assay to suggest that they compete for the same receptors on the HeLa cell surface. The finding that input multiplicities of B3 virus which exceeded 500 saturated the homologous viral receptors of HeLa cells was unexpected, but was consistent with the results of interference assays. Excessive amounts of input virus did not, however, inhibit eclipse of homologous cell-associated virus. Attachment interference between enteroviruses occurred even though the interfering virus was eclipsed prior to addition of challenge virus. The finding that enterovirus attachment interference was reversible with acid
p
H suggested that attachment and eclipse of enterovirus does not result in a permanent alteration of the cell membrane and that these events occur at the cell surface.
Interactions of Human Cytomegalovirus with Human Fibroblasts
Authors: Vonka Vladimir , Benyesh-Melnick Matilda
Published: January 2020

Vonka, Vladimir(Baylor University College of Medicine, Houston, Tex.),and Matilda Benyesh-Melnick. Interactions of human cytomegalovirus with human fibroblasts. J. Bacteriol.91:213–220. 1966.—Virus attachment of human cytomegalovirus to human embryo lung fibroblasts was found to be temperature-independent, from 4 to 37 C. Prolonged incubation at 4 C, however, resulted in inactivation of a high proportion of attached virus. Virus penetration seemed to be temperature-dependent, occurring at 37 C but not at 4 C. Detailed studies of the growth curve of the virus were made. Cell-associated virus preceded the appearance of virus in the fluid phase by 2 to 5 days. Complement-fixing antigen could be detected, but only when the cytopathic effect was advanced, and it was demonstrable only in the cell-associated fraction. Under methyl cellulose, decreasing the bicarbonate concentration in the overlay from 0.225 to 0.15% resulted in marked increase in plating efficiency with all strains tested. However, varying the concentration of bicarbonate from 0.3 to 0.15% in fluid medium did not influence the growth of virus.
Comparative Aspects of Some Bacterial Dehydrogenases and Transhydrogenases
Authors: Ragland T. E. , Kawasaki T. , Lowenstein J. M.
Published: January 2020

Ragland
, T. E. (Brandeis University, Waltham, Mass.),
T. Kawasaki, and J. M. Lowenstein
. Comparative aspects of some bacterial dehydrogenases and transhydrogenases. J. Bacteriol.
91:
236–244. 1966.—Twenty-eight diverse bacterial species were surveyed for the activities and coenzyme specificities of four enzymes: isocitrate dehydrogenase (ICDH), glucose-6-phosphate dehydrogenase (G-6-PDH), 6-phosphogluconate dehydrogenase (6-PGDH), and reduced nicotinamide adenine dinucleotide phosphate-nicotinamide adenine dinucleotide (NAD) transhydrogenase (TH). Most of the species that exhibited a nicotinamide adenine dinucleotide phosphate (NADP)-linked ICDH also showed significant TH activity, but there were several which did not. Only one of the organisms tested,
Xanthomonas pruni
, had an ICDH active with both NAD and NADP; it was devoid of TH activity.
Acetobacter suboxydans
, which lacks ICDH altogether, also had no TH. Some of the species examined had G-6-PDH or 6-PGDH (or both) of dual coenzyme specificity, but there was no apparent relation between these findings and the presence or absence of TH. The TH reaction was assayed by use of analogues of NAD as acceptors. The bacteria could be divided into two groups on the basis of TH specificity, one group reacting at a much faster rate with the 3-acetylpyridine analogue of NAD than with the thionicotinamide analogue, whereas the converse was true for the other group. A few organisms showed no marked specificity for either analogue. This division of specificity can be related to the currently accepted taxonomic classification of the organisms, although a few apparent anomalies were found.
New Approach to the Genetics ofStreptomyces coelicolor
Authors: Sermonti G. , Bandiera Milena , Spada-Sermonti Isabella
Published: January 2020

Sermonti, G. (Istituto Superiore di Sanità, Rome, Italy),Milena Bandiera, and Isabella Spada-Sermonti. New approach to the genetics ofStreptomyces coelicolor. J. Bacteriol.91:384–392. 1966.—Mixed cultures of complementary auxotrophic strains ofStreptomyces coelicolorA3(2) were preincubated on discs of cellophane on complete medium and were then transferred onto selective media. When one strain was streptomycin-resistant and the other was streptomycin-sensitive, and the transfer medium contained streptomycin, distinct minute tufts of aerial mycelium appeared on the background growth of the mixed culture. They turned out to be heterozygous clones (heteroclones) in which the streptomycin-sensitive allele was, as a rule, missing. The pattern of marker contribution of the streptomycin-sensitive parent to the zygotes was indicative of a continuous structure carrying the hereditary material. A gradual transfer of the donor genome during conjugation was suggested by the progressive completion of the zygotes obtained by increasing preincubation time.
Structural Changes in the Cell Wall ofSchizosaccharomyces pombeDuring Cell Division
Authors: Streiblová Eva , Málek I. , Beran K.
Published: January 2020

Streiblová, Eva(Czechoslovak Academy of Sciences, Prague, Czechoslovakia),I. Málek, and K. Beran. Structural changes in the cell wall ofSchizosaccharomyces pombeduring cell division. J. Bacteriol.91:428–435. 1966.—Individual stages of growing and dividing cells ofSchizosaccharomyces pombewere studied by means of fluorescence and electron microscopy with the use of metal-shadowed isolated walls, replicas, and ultrathin sections. Vegetative cells were found to contain division scars (six at the most); their formation and structure are described. More data on the growth of arthrospores were obtained. New structural observations were made on the architecture of the cell wall (original wall ring, polar cell wall, plug wall band, additional wall ring). Structural changes of cell surfaces and lateral walls during fission are represented schematically to the fourth generation. The question of origin of the septum is discussed, and on this basis the entire structure of the cell wall is interpreted.
Action of Streptolysin S, the Group D Hemolysin, and Phospholipase C on Whole Cells and Spheroplasts
Authors: Davie Joseph M. , Brock Thomas D.
Published: January 2020

Davie, Joseph
M. (Indiana University, Bloomington),
and Thomas D. Brock
. Action of streptolysin S, the group D hemolysin, and phospholipase C on whole cells and spheroplasts. J. Bacteriol.
91:
595–600. 1966.—The effect of streptolysin S, the group D hemolysin, and phospholipase C (the α toxin of
Clostridium perfringens
) on whole cells and spheroplasts or protoplasts of three strains of streptococci and
Micrococcus lysodeikticus
was tested. Viability, C
14
-glycine uptake, and lysis were measured. The group D hemolysin and phospholipase C were active against whole bacteria; streptolysin S was not. All three substances were active on spheroplasts. A partially resistant mutant derived from a strain sensitive to the group D hemolysin was also partially resistant to streptolysin S and phospholipase C. Antimycin A protected spheroplasts from streptolysin S but not from the group D hemolysin.
Insights into the Gene Expression Profiles of Active and Restricted Red/Green-HIV
+
Human Astrocytes: Implications for Shock or Lock Therapies in the Brain
Authors: Edara Venkata Viswanadh , Ghorpade Anuja , Borgmann Kathleen
Published: January 2020

More than 36 million people are living with HIV-1 worldwide, and despite antiretroviral therapy, 30 to 50% of the people living with HIV-1 suffer from mild to moderate neurocognitive disorders. HIV-1 reservoirs in the central nervous system (CNS) are challenging to address due to low penetration of antiretroviral drugs, lack of resident T cells, and permanent integration of provirus into neural cells such as microglia and astrocytes. Several studies have shown astrocyte dysfunction during HIV-1 infection. However, little is known about how HIV-1 latency affects their function. The significance of our research is in identifying that the majority of HIV
+
astrocytes restrict HIV expression and were resistant to reactivation. Further, simply harboring the HIV genome profoundly altered astrocyte biology, resulting in a proinflammatory phenotype and functional changes. In this context, therapeutic strategies to reactivate or silence astrocyte HIV reservoirs, without excising proviral DNA, will likely lead to detrimental neuropathological outcomes during HIV CNS infection.
Repurposing Papaverine as an Antiviral Agent against Influenza Viruses and Paramyxoviruses
Authors: Aggarwal Megha , Leser George P. , Lamb Robert A.
Published: January 2020

Influenza viruses are important human pathogens that are the causative agents of epidemics and pandemics. Despite the availability of an annual vaccine, a large number of cases occur every year globally. Here, we report that papaverine, a vasodilator, shows inhibitory action against various strains of influenza virus as well as the paramyxoviruses PIV5, HPIV3, and RSV. A significant effect of papaverine on the influenza virus morphology was observed. Papaverine treatment of influenza-virus-infected cells resulted in the inhibition of virus at a later time in the virus life cycle through the suppression of nuclear export of vRNP and also interfered with the host cellular cAMP and MEK/ERK cascade pathways. This study explores the use of papaverine as an effective inhibitor of both influenza viruses as well as paramyxoviruses.
Identification of Key Determinants of Staphylococcus aureus Vaginal Colonization
Authors: Deng Liwen , Schilcher Katrin , Burcham Lindsey R. , Kwiecinski Jakub M. , Johnson Paige M. , Head Steven R. , Heinrichs David E. , Horswill Alexander R. , Doran Kelly S.
Published: January 2020

Staphylococcus aureus
is an opportunistic pathogen able to cause a wide variety of infections in humans. Recent reports have suggested an increasing prevalence of MRSA in pregnant and postpartum women, coinciding with the increased incidence of MRSA infections in neonatal intensive care units (NICUs) and newborn nurseries. Vertical transmission from mothers to infants at delivery is a likely route of MRSA acquisition by the newborn; however, essentially nothing is known about host and bacterial factors that influence MRSA carriage in the vagina. Here, we established a mouse model of vaginal colonization and observed that multiple MRSA strains can persist in the vaginal tract. Additionally, we determined that MRSA interactions with fibrinogen and iron uptake can promote vaginal persistence. This study is the first to identify molecular mechanisms which govern vaginal colonization by MRSA, the critical initial step preceding infection and neonatal transmission.
Diffuse large B-cell lymphoma of the vagina in pregnancy
Authors: Anusim Nwabundo , Ionescu Filip , Afolayan-Oloye Olabisi , Gaikazian Susanna S
Published: January 2020

A 28-year-old primigravida was evaluated for complaints of difficulty urinating and pelvic pain of 6-weeks duration. She denied fever, night sweats, weight loss or fatigue. Pelvic ultrasonography revealed a single fetal pole with cardiac activity and a 7 cm mass in the anterior vagina which encased the urethra. The diagnosis of diffuse large B-cell lymphoma germinal centre type was made on analysis of biopsied pelvic mass. Whole body MRI revealed the disease was limited to the vagina. The patient received six cycles of Rituximab-cyclophosphamide, doxorubicin, vincristine and prednisone with significant improvement in her symptoms. Serial ultrasounds over the subsequent months showed appropriate development of the fetus. Whole body MRI after treatment showed decreased size and decreased signal of the primary pelvic mass compatible with favourable treatment response. Challenges in the management of this rare presentation of lymphoma are discussed.
Adaptive Dynamic Surface Control for a Class of Nonlinear Pure-Feedback Systems with Parameter Drift
Authors: He Cheng , Wu Jian , Ying Jin , Dai Jiyang , Zhang Zhe , Jiang Liangxing
Published: January 2020

In order to solve the problem of unknown parameter drift in the nonlinear pure-feedback system, a novel nonlinear pure-feedback system is proposed in which an unconventional coordinate transformation is introduced and a novel unconventional dynamic surface algorithm is designed to eliminate the problem of “calculation expansion” caused by the use of backstepping in the pure-feedback system. Meanwhile, a sufficiently smooth projection algorithm is introduced to suppress the parameter drift in the nonlinear pure-feedback system. Simulation experiments demonstrate that the designed controller ensures the global and ultimate boundedness of all signals in the closed-loop system and the appropriate designed parameters can make the tracking error arbitrarily small.
Optimization of Interplanetary Trajectories Using the Colliding Bodies Optimization Algorithm
Authors: Del Monte Marco , Meles Raffaele , Circi Christian
Published: January 2020

In this paper, a recent physics-based metaheuristic algorithm, the Colliding Bodies Optimization (CBO), already employed to solve problems in civil and mechanical engineering, is proposed for the optimization of interplanetary trajectories by using both indirect and direct approaches. The CBO has an extremely simple formulation and does not depend on any initial conditions. To test the performances of the algorithm, missions with remarkably different orbital transfer energies are considered: from the simple planar case, as the Earth-Mars orbital transfer, to more energetic ones, like a rendezvous with the asteroid Pallas.
Sufismo versus Islamismo
Authors: Yunis Leandra
Published: January 2020

Resenha crítica e ensaística do livro "The house of islam - a gobal history" de Ed Husein, recém lançado no Reino Unido.
Nationalism in a new Syria
Authors: Bercito Diogo
Published: January 2020

This article investigates the role of the mahjar on the development of Arab nationalism, with a particular interest in Antoun Saadeh’s experience in Latin America. Like many other Arab nationalism ideologues, he developed his conception of the “nation” during the years he spent abroad. His ideas were present in Suriya al Jadida, a newspaper he published in Brazil from 1939 to 1941. I analyze three articles from that publication in order to understand how he reached out to the diaspora in Latin America and the role he expected it to play. With that, I emphasize the importance of the mahjar to the political thought of Arabic-speaking countries.
Alimentação e escravidão no vale do rio Cauca, Nova Granada, através dos olhos de romancistas e viajantes (1750-1851)
Authors: Gómez Esteban Zabala
Published: January 2020

O presente trabalho pretende abordar o uso da literatura, principalmente romances costumbristas do século XIX e relatos de viajantes estrangeiros do mesmo período, como fonte histórica para a análise das práticas alimentares dos escravizados da região do vale do rio Cauca, na Nova Granada, durante os anos de 1750 – última etapa do comércio negreiro – até 1851 – o fim da escravidão. Já o historiador da alimentação Henrique Carneiro, no seu texto As fontes para os estudos históricos sobre a alimentação (2005), prestou atenção na dificuldade que essa área da história tem quanto à pouca quantidade de documentos oficiais úteis para a compreensão dos fenômenos alimentares. Porém, o pesquisador faz um chamado para o uso de múltiplos tipos de fontes, dos quais os relatos de viagens, crônicas e romances sobressaem.

Portanto, no decorrer desta pesquisa tem sido importante prestar especial atenção às metodologias necessárias para o uso da literatura como fonte histórica, assim, temos nos aproximado às teorias produzidas principalmente pela História Cultural, que propõem que para analisar esse tipo de fonte é necessário entender que o que é escrito pelos romancistas e viajantes são representações da realidade e, portanto, como escreveu o historiador José da Silva Horta no seu texto “Nações”, marcadores identitários e complexidades da representação étnica nas escritas portuguesas de viagem: Guiné do Cabo Verde (séculos XVI e XVII), publicado em 2013, essas representações provinham de uma “grelha cultural” de que dispunham os europeus para representar, no nosso caso, os escravizados e libertos, sendo o conceito de representação fundamental para entender os métodos para o análise da literatura desde uma perspectiva histórica.

Assim, este trabalho é uma tentativa de compreender o complexo contexto de contato cultural produto da colonização espanhola nas Américas e o comércio transatlântico de pessoas originárias de diferentes partes da África Ocidental, através das suas práticas alimentares: utensílios, alimentos e preparações, representadas por esses romancistas e viajantes.

Finalmente, os romances aqui usados são María de Jorge Isaacs (1867) e El alférez real de Eustaquio Palacios (1886), ademais dos relatos de viajantes de diferentes nacionalidades como o frei espanhol Juan de Santa Gertrudis, que viajou à Nova Granada entre 1757 e 1767, o coronel britânico John Potter Hamilton, que esteve na década de 20 do século XIX, e o botânico estadunidense Isaac Holton, que passou pelo vale do Cauca no ano de 1851.
Alimentação em Os Parceiros do Rio Bonito
Authors: Silva Nichole Ramos da , Kraemer Fabiana Bom
Published: January 2020

Trata-se de uma análise de um clássico da literatura brasileira, Os Parceiros do Rio Bonito, escrito por Antonio Candido em meados de 1954, que reflete a cultura dos caipiras paulistas em um determinado momento histórico. Voltar ao passado é uma forma de compreender aspectos do presente e quiçá do futuro. A transformação dos meios de vida desse grupo social frente à urbanização pode ser profícua para refletir sobre as novas formas de ruralidade. O recorte aqui adotado refere-se à relação entre produção dos meios de vida e sociabilidade através da alimentação. Para tanto, foram selecionados para análise os capítulos 9, 10 e 11. O caipira paulista, grupo que em sua constituição combina traços culturais indígenas e portugueses e que obedece ao ritmo nômade do bandeirante, pode ser visto como uma espécie de retrato das culturas tradicionais do homem do campo, que apresentam formas de persistências e manutenção de sua autonomia e de seus modos de vida tradicionais, porém, quando confrontadas pela cultura urbana, tendem a incorporar seus traços, principalmente no que diz respeito à cultura material. Antonio Candido sinaliza que o caipira se alimentava no plano da subsistência, realizando, em média, quatro refeições ao dia: café da manhã, almoço, merenda e jantar. Apesar das restrições alimentares acompanhadas de fome fisiológica e psíquica, definida pelo autor como o desejo constante de misturas, os caipiras não se fechavam em seus universos sociais e alimentares, ao contrário, compartilhavam carnes por meio da caça, promoviam empréstimos de alimentos e davam festas. A obtenção dos alimentos foi marcada pela passagem de uma alimentação pautada pelo autoconsumo para uma onde havia crescente aquisição de gêneros do comércio. O caipira que optou por priorizar a manutenção dos aspectos culturais de sua vida se defrontou com a fome, para além daquela psíquica, a que já estava habituado e que figurava no plano dos desejos, mas a fome física que ronca e dói. Observamos outro fenômeno, o do maior isolamento e individualização entre os caipiras, que diminuíram a realização de festas e socialização da comida através do compartilhamento das carnes caçadas. Através da presente análise, observamos que as mudanças ocorridas na alimentação dos caipiras estiveram sempre associadas às mudanças econômicas e sociais, que, como resultado de incorporações progressivas da economia moderna, afetaram a organicidade da vida social e causaram rupturas em diversos aspectos da vida do grupo. Hoje, podemos concluir que o fenômeno da urbanização se constituiu como uma ameaça à Soberania e Segurança Alimentar e Nutricional dos caipiras, uma vez que influenciou seus modos de plantar, retirando-lhes protagonismo e autonomia; implicou no acesso regular a alimentos, em quantidade e qualidade necessárias; alterou aspectos fundamentais para seu equilíbrio social e ecológico e contribuiu para perda de características tradicionais da alimentação.