bluuebunny/crossref_metadata_2025 huggingface dataset:
PRODUCTION AND BIOLOGICAL CHARACTERISTICS OF AN EXTRACELLULAR NEUROTOXIN FROM
MYCOPLASMA NEUROLYTICUM
Authors: Tully Joseph G.
Published: January 2020

Tully, Joseph
G. (National Institute of Allergy and Infectious Diseases, Bethesda, Md.). Production and biological characteristics of an extracellular neurotoxin from
Mycoplasma neurolyticum
. J. Bacteriol.
88:
381–388. 1964.—Toxigenic strains of
Mycoplasma neurolyticum
were found to produce a potent extracellular neurotoxin for mice under a variety of cultural conditions. The observed biological characteristics of this toxin were quite similar to those originally described by Sabin. The toxin was again found to be readily inactivated by prolonged incubation and, when separated from
Mycoplasma
cells by filtration, possessed a greater heat resistance than whole cells. Young mice and rats were generally susceptible to neurotoxin, whereas most other experimental animals were resistant. Filtration results confirmed a minimal reproductive unit of 125 to 200 mμ for two neurotoxic
Mycoplasma
strains, with both cell-free filtrates reproducing the rolling disease syndrome in mice. Twice-washed
Mycoplasma
cells were also observed to be as neurotoxic as filtrates. Plate counting results revealed an intravenous
ld
50
of approximately 3 × 10
8
washed cells for young mice.
RELATIVE PLAQUE-FORMING, CELL-INFECTING, AND INTERFERING QUALITIES OF VACCINIA VIRUS
Authors: Galasso G. J. , Sharp D. G.
Published: January 2020

Galasso
, G. J. (University of North Carolina School of Medicine, Chapel Hill),
and D. G. Sharp
. Relative plaque-forming, cell-infecting, and interfering qualities of vaccinia virus. J. Bacteriol.
88:
433–439. 1964.—The growth of vaccinia virus in slant cultures of L cells inoculated with different multiplicities of counted particles suggests a higher incidence of cell infection than can be accounted for by the number of plaque-forming units. From cultures containing antiserum or heated virus to limit the passage of progeny to uninfected cells, the data clearly indicate the ability of all the particles to infect cells even though the plaque titer is only one-tenth of this number. Analogous experiments show that an average of two heat-inactivated (56 C, 45 min) particles induce interference in L cells. There is nothing yet to show whether the few plaque-forming particles are different from the majority or whether they are just statistically fortunate in the complex process of plaque formation.
EFFECTS OF BICARBONATE ON GROWTH OF
PASTEURELLA PESTIS
II
Authors: Baugh C. L. , Lanham J. W. , Surgalla M. J.
Published: January 2020

Baugh
, C. L. (Fort Detrick, Frederick, Md.),
J. W. Lanham, and M. J. Surgalla
. Effects of bicarbonate on growth of
Pasteurella pestis
. II. Carbon dioxide fixation into oxalacetate by cell-free extracts. J. Bacteriol.
88:
553–558. 1964.—Enzyme preparations from
Pasteurella pestis
will carboxylate phosphoenolpyruvate to form oxalacetate by two distinct reactions. The reactions are similar to those catalyzed by the enzymes, phosphoenolpyruvic carboxylase and phosphoenolpyruvate carboxykinase. No significant differences in enzyme characteristics or enzyme content were found when virulent cells were compared with avirulent under the conditions of our experiments. The carboxykinase of
P. pestis
differs from that of animal origin, because it is dependent upon adenine derivatives rather than inosine or guanosine nucleotides. The latter two nucleotides can act indirectly by way of adenosine nucleotides, because nucleoside diphosphokinase and myokinase are present in the extract.
INDUCIBLE RESISTANCE TO ERYTHROMYCIN IN
STAPHYLOCOCCUS AUREUS
Authors: Weaver Judith R. , Pattee P. A.
Published: January 2020

Weaver, Judith
R. (Iowa State University, Ames),
and P. A. Pattee
. Inducible resistance to erythromycin in
Staphylococcus aureus
. J. Bacteriol.
88:
574–580. 1964.—The dissociated resistance of
Staphylococcus aureus
to erythromycin was examined and was found to possess the characteristics of an inducible enzyme. The induction of resistance to high concentrations of erythromycin in
S. aureus
occurred only after prior exposure to subinhibitory concentrations of erythromycin. The only macrolide antibiotic examined which induced resistance was erythromycin, and the resistance of induced populations was rapidly lost when they were grown in the absence of this antibiotic. Induction did not occur when protein synthesis was inhibited by either chloramphenicol or histidine starvation of a histidine auxotroph. The macrolide antibiotics inhibited the induction of resistance at the same minimal concentrations required to inhibit growth and induced synthesis of β-galactosidase. Therefore, the mode of action of the macrolide antibiotics is to inhibit protein synthesis, and the induction of resistance overcomes this inhibition in some manner which is associated with the synthesis of new protein.
CATALASE ACTIVITY IN
LEPTOSPIRA
Authors: Rao P. J. , Larson A. D. , Cox C. D.
Published: January 2020

Rao
, P. J. (University of Illinois, Urbana), A. D.
Larson, and C. D. Cox
. Catalase activity in
Leptospira
. J. Bacteriol.
88:
1045–1048. 1964.—A number of serotypes of
Leptospira
were found to possess catalase activity, although considerable variation in activity existed among various serotypes. Catalase activity of
L. pomona
was reduced by inhibitors commonly employed for arresting catalase activity in other biological systems. Catalase activity was increased three to five times by growing cultures under conditions of oxygen availability; however, aeration had no beneficial effect on total viable cell crop. The relationship of oxygen to metabolism and future studies on virulence of the leptospirae is discussed.
MULTIPLE SCARS, A NEW TYPE OF YEAST SCAR IN APICULATE YEASTS
Authors: Streiblová Eva , Beran K. , Pokorný V.
Published: January 2020

Streiblová, Eva
(Czechoslovak Academy of Sciences, Prague, Czechoslovakia),
K. Beran, and V. Pokorný
. Multiple scars, a new type of yeast scar in apiculate yeasts. J. Bacteriol.
88:
1104–1111. 1964.—A new type of yeast scar is described in apiculate yeasts:
Saccharomycodes, Nadsonia, Hanseniaspora
, and
Kloeckera
. These scars are formed on the distal poles of the cell walls in the course of vegetative reproduction, and are the cause of the formation of the apiculate form of the cells. The structure of multiple scars was studied by fluorescence microscopy and by electron microscopy on carbon replicas and isolated cell walls. The discussion deals with the importance of described cytological structures for the morphogenesis of cells and for determining individual reproductive capacity of cells, and considers some questions related to the interpretation of the development of multiple scars.
METABOLISM OF PENTOSES AND PENTITOLS BY
AEROBACTER AEROGENES
II
Authors: Mortlock R. P. , Wood W. A.
Published: January 2020

Mortlock
, R. P. (Michigan State University, East Lansing),
and W. A. Wood
. Metabolism of pentoses by
Aerobacter aerogenes
. II. Mechanism of acquisition of kinase, isomerase, and dehydrogenase activity. J. Bacteriol.
88:
845–849. 1964.—
Aerobacter aerogenes
PRL-R3 possesses the genetic information to synthesize, in the presence of the appropriate inducer, at least three members of the family of ketopentokinases, two members of the family of pentitol dehydrogenases, and two members of the family of aldopentose isomerases. That is,
d
-xylulokinase,
d
-ribulokinase,
l
-ribulokinase, ribitol dehydrogenase,
d
-arabitol dehydrogenase,
d
-xylose (→
d
-xylulose) isomerase, and
l
-arabinose (→
l
-ribulose) isomerase activities were detectable within 4 hr after addition of inducer. The possibility that mutation and selection are involved in the formation of
l
-xylulokinase,
l
-arabitol dehydrogenase,
d
-arabinose (→
d
-ribulose) isomerase and
d
-lyxose (→
d
-xylulose) isomerase could not be eliminated, because 11 hr or more of incubation after the addition of inducer were required before the appearance of these enzyme activities.
d
-Xylulokinase activity was induced in less than 2 hr when
d
-xylose or
d
-arabitol were inducers, but 45 hr were required for the appearance of activity when xylitol was the inducer, and 83 hr were required when
d
-lyxose was the inducer. Likewise, the time required for induction of ribitol dehydrogenase was 2 hr for ribitol, 12 hr for
d
-arabinose, and 45 hr for xylitol. The time required for the appearance of enzyme activity correlated with the time required for the beginning of cell growth and substrate utilization.
AMINO ACIDS AS PROTECTIVE COMPOUNDS IN ULTRAVIOLET-IRRADIATED
hANSENULA WINGEI
Authors: Hunt D. E.
Published: January 2020

Hunt, D. E.
(Charles V. Chapin Hospital, Providence, R.I.). Amino acids as protective compounds in ultraviolet-irradiated
Hansenula wingei
. J. Bacteriol.
88:
893–895. 1964.—”Prefeeding”
Hansenula wingei
with small concentrations of either tryptophan, cystine, tyrosine, phenylalanine, leucine, cysteine, threonine, isoleucine, ethionine, norvaline, or histidine protected this yeast against inactivating ultraviolet treatment. ”Prefeeding” with methionine, proline, or alanine conferred little if any protection, and valine or serine caused this organism to be more sensitive to ultraviolet inactivation. A direct relation exists between the concentration of the protective amino acids and the number of surviving cells. The heterocyclic and aromatic amino acids are generally more protective than the corresponding aliphatic compounds. The diversity of the compounds as well as quantitative differences in the protection afforded by them suggest that they have different modes of action.
EPISOME-MEDIATED TRANSFER OF DRUG RESISTANCE IN ENTEROBACTERIACEAE VIII
Authors: Watanabe Tsutomu , Ogata Chizuko , Sato Sachiko
Published: January 2020

Watanabe, Tsutomu
(Keio University School of Medicine, Tokyo, Japan),
Chizuko Ogata, and Sachiko Sato
. Episome-mediated transfer of drug resistance in Enterobacteriaceae. VIII. Six-drug-resistance R factor. J. Bacteriol.
88:
922–928. 1964.—The multiple-drug-resistant
Escherichia coli
strain isolated by Lebek in 1963 was found to transfer resistance to sulfonamide, streptomycin, chloramphenicol, tetracycline, kanamycin, and neomycin together by conjugation, as well as by transduction with phage P1kc, suggesting that these drug-resistance markers are carried by a single R factor (R
6
). The results of transductional and spontaneous segregations of the drug-resistance markers of R
6
have shown that R
6
has independent genetic determinants for sulfonamide, streptomycin, chloramphenicol, tetracycline, and kanamycin-neomycin resistance. Resistance to kanamycin and neomycin is probably controlled by a single gene, because no segregation was observed between these two. The resistance transfer factor of R
6
was found to be of the
fi
+
type.
ACRIDINE ORANGE BINDING BY
MICROCOCCUS LYSODEIKTICUS
Authors: Beers Roland F.
Published: January 2020

Beers, Roland F., Jr.
(Johns Hopkins University, Baltimore, Md). Acridine orange binding by
Micrococcus lysodeikticus
. J. Bacteriol.
88:
1249–1256. 1964.—
Micrococcus lysodeikticus
cells bind acridine orange (AO) reversibly. The adsorption isotherm is consistent with a highly cooperative-type binding similar to that observed with polyadenylic acid. The cells exhibit a strong buffering action on the concentration of free AO which remains constant (1 μg/ml) over a range from 5 to 95% saturation of the cells by AO. The cells stain either fluorescent orange or green. The fraction stained orange is directly proportional to the quantity of dye adsorbed, indicating that these cells bind a fixed amount of AO (10% of dry weight). The green-stained cells contain less than 1% of the AO bound to orange-stained cells. The results suggest that the abrupt increase in amount of AO bound by the orange-stained cells occurs when the concentration of free AO reaches a threshold concentration. Similar results were obtained with
Bacillus cereus
. Mg increases the free AO concentration and the extent of binding capacity of the cells.
EVALUATION OF SEROLOGICAL AND CULTURAL METHODS FOR THE DIAGNOSIS OF CHRONIC SALMONELLOSIS IN MICE
Authors: Morello Josephine A. , Digenio Teresa A. , Baker Edgar E.
Published: January 2020

Morello, JosephineA. (Boston University School of Medicine, Boston, Mass.),Teresa A. Digenio, and Edgar E. Baker. Evaluation of serological and cultural methods for the diagnosis of chronic salmonellosis in mice. J. Bacteriol.88:1277–1282. 1964.—Mice were infected by inoculation of varying doses of a virulent culture ofSalmonella typhimuriumdirectly into the stomach. Feces were cultured at intervals on Brilliant Green and Eosin Methylene Blue Agar. Most survivors shed organisms consistently during the early stage of infection, but, after 1 month, a large number had become intermittent shedders. These animals would have been considered salmonella-free if cultured at a time when they were not shedding the organism. Serological tests to detect antibodies in their sera, therefore, were investigated. Standard agglutination, and hemagglutination and hemolytic tests with the use of sheep erythrocytes modified with extracts ofS. typhimurium, were performed with sera from infected mice. It was possible to detect smaller amounts of antibody in the sera by means of the hemolytic test, and this test was often positive when the others were negative. Antibodies detectable by the hemolytic test appeared within 21 days after inoculation, and were present in the sera of surviving animals for 3 months or longer. All animals known to be infected gave positive serological reactions. Cultural techniques were most satisfactory for detection of salmonellosis during early stages of infection, and serological tests were of primary value at later intervals. Concurrent use of both techniques ensured discovery of the largest number of infected animals.
RELATIONSHIP BETWEEN ULTRAVIOLET SENSITIVITY AND ABILITY TO PROPAGATE ULTRAVIOLET-IRRADIATED BACTERIOPHAGE
Authors: Hill Ruth F.
Published: January 2020

Hill, Ruth
F. (Columbia University, New York, N.Y.). Relationship between ultraviolet sensitivity and ability to propagate ultraviolet-irradiated bacteriophage. J. Bacteriol.
88:
1283–1287. 1964.—Mutants with a reduced ability to propagate ultraviolet-damaged bacteriophage T
1
were isolated from
Escherichia coli
strain B/r. The change in this ability varied from a slight to a very marked loss; the greater the loss, the greater was the ultraviolet sensitivity of the mutant. Reduced ability to propagate irradiated T
1
appears to be the more sensitive index of genetic change, because in one mutant there was no significant reduction in ultraviolet resistance. In a converse study, second-step mutants with an increased ultraviolet resistance were obtained from a mutant of
E. coli
B. This mutant is both unable to propagate irradiated T
1
and very ultraviolet-sensitive. The increased ultraviolet resistance of the second-step mutants was not accompanied by an increased ability to propagate irradiated T
1
.
RESPONSES OFBACILLUS SUBTILISSPORES TO IONIC ENVIRONMENTS DURING SPORULATION AND GERMINATION
Authors: Fleming H. P. , Ordal Z. John
Published: January 2020

Fleming, H. P. (University of Illinois, Urbana),and Z. John Ordal. Responses ofBacillus subtilisspores to ionic environments during sporulation and germination. J. Bacteriol.88:1529–1537. 1964.—The ionic environments of germination and sporulation menstrua had a prominent influence on characteristics ofBacillus subtilisspores. There was a synergistic effect forl-alanine and inorganic ions on spore germination. The maximal rate of germination in solutions ofl-alanine was dependent on ionic concentration and species. Germination was negligible inl-alanine at low ionic strength but increased as the ionic strength was increased up to about 10−1mwith a variety of salts. Phosphate was the most active ion tested, and divalent cations were the least active in supporting germination inl-alanine. Germination progressed slowly at 45 C in sodium chloride or sodium phosphate alone but not in CaCl2alone. Germination rates inl-alanine were retarded at high ionic strengths (μ in the range of 0.1 to 1.0). Inhibitory effects of high concentrations of certain divalent cations on germination were related to the binding abilities of these metals. High concentrations of NaCl (10−1to 1.0m) in the sporulation medium resulted in lowered heat resistance and germination rate of the resulting spores. The addition of calcium (5 × 10−2mCaCl2) to the sporulation medium relieved the repression of NaCl on germination and caused the spores to have a greater heat resistance. Calcium and dipicolinic acid (DPA) contents of the spores were unaffected by NaCl in the sporulation medium. The calcium, but not the DPA, content of spores increased as a result of supplementing the sporulation medium with calcium. Possible roles of ions in the germination of spores are discussed.
TEMPERATURE-HYDROSTATIC PRESSURE STUDIES ON PARTIALLY PURIFIED INORGANIC PYROPHOSPHATASE ACTIVITY
Authors: Morita Richard Y. , Mathemeier Paul F.
Published: January 2020

Morita, Richard
Y. (Oregon State University, Corvallis),
and Paul F. Mathemeier
. Temperature-hydrostatic pressure studies on partially purified inorganic pyrophosphatase activity. J. Bacteriol.
88:
1667–1671. 1964.—Partially purified inorganic pyrophosphatase from
Bacillus stearothermophilus
demonstrated increased activity at 90 C with hydrostatic pressures of 100 to 1,100 atm. At 90 C, optimal activity was at 700 atm. No enzyme activity could be demonstrated at 100 C at 1 atm; however, at 105 C moderate hydrostatic pressures favored the enzyme reaction, resulting in increased activity. The increased enzyme activity is explained on the basis of pressure counteracting the molecular volume increase which results from elevated temperature. Thermal denaturation studies at 90 C show inorganic pyrophosphatase to be more stable in the presence of cofactor than substrate, and indicate an enyzme-cofactor intermediate in the hydrolysis.
MORPHOLOGICAL CHANGES IN GRAM-NEGATIVE BACILLI EXPOSED TO CEPHALOTHIN
Authors: Chang Te-Wen , Weinstein Louis
Published: January 2020

Chang, Te-Wen
(Tufts University School of Medicine, Boston, Mass.),
and Louis Weinstein
. Morphological changes in gram-negative bacilli exposed to cephalothin. J. Bacteriol.
88:
1790–1797. 1964.—Exposure of gram-negative bacteria to cephalothin (7-[thiophene-2-acetamido]-cephalosporanic acid) revealed the formation of long filaments and large bodies, which were capable of reverting to normal cells when removed from contact with the drug. The degree of morphological change was found to be related to the concentration of antibiotic in which the organisms were suspended. The large bodies were altered by contact with solutions of varying osmolarity. Different species showed variation in the ability to develop large bodies. A relationship between antibiotic sensitivity and the capacity to resist morphological alteration was observed. Though most sensitive gram-negative bacilli were strikingly changed by exposure to cephalothin, naturally resistant ones were unaffected. Organisms made drug-resistant in vitro underwent changes in cellular form which were qualitatively the same but less intense than those which developed in parent strains originally sensitive to cephalothin.
Cyanide Formation by
Chromobacterium violaceum
Authors: Michaels Ruth , Corpe W. A.
Published: January 2020

Michaels, Ruth
(Columbia University, New York, N.Y.),
and W. A. Corpe
. Cyanide formation by
Chromobacterium violaceum
. J. Bacteriol.
89:
106–112. 1965.—The formation of cyanide by a
Chromobacterium violaceum
strain was studied with growing cultures and with nonproliferating cells grown in complex and chemically defined media. Most of the cyanide was produced during the log-phase growth of the organism, and accumulated in the culture supernatant fluid. A synergistic effect of glycine and methionine on cyanide formation in a chemically defined medium was observed, and the amount of cyanide formed was found to be dependent on the concentrations of the two substances. Cyanide formation by nonproliferating cells was stimulated by preincubation with glycine and methionine. Cyanide formation by adapted cells in the presence of glycine and methionine was stimulated by succinate, malate, or fumarate, and depressed by azide and 2,4-dinitrophenol. Methionine could be replaced by betaine, dimethylglycine, and choline.
Colorimetric Determination of Color of Aerial Mycelium of Streptomycetes
Authors: Lyons Allister J. , Pridham Thomas G.
Published: January 2020

Lyons, Allister J., Jr
. (Northern Regional Research Laboratory, Peoria, Ill.)
and Thomas G. Pridham
. Colorimetric determination of color of aerial mycelium of streptomycetes. J. Bacteriol.
89:
159–169. 1965.—For some time, streptomycete taxonomists have been seeking to describe more accurately the colors of aerial mycelium. Some of the descriptive systems involve many different color names and groups. Others combine many colors into a few groups. All the systems and methods leave much to be desired. To obtain an accurate description, a colorimeter with a reflectance attachment was used to examine streptomycete aerial mycelium of 37 strains, representing all of the major aerial mycelium color groups. Each color was characterized by three values: dominant wavelength in millimicrons, and purity and brightness in percentages. All colors of aerial mycelium were of low purity (< 25%). Most of the dominant wavelengths were in the yellow to yellow-green bands of the spectrum. Most of the color tabs matched visually with the streptomycete strains had purities of a higher value than those of the cultures. The reflectance instrument seems to allow an objective description, and its use may help to clarify the color problem with streptomycetes. It is concluded that present color descriptions are inadequate and that the significance of color in speciation requires critical examination.
Induction and Properties of a Temperate Bacteriophage from
Bacillus stearothermophilus
Authors: Welker N. E. , Campbell L. Leon
Published: January 2020

Welker
, N. E. (University of Illinois, Urbana),
and L. Leon Campbell
. Induction and properties of a temperate bacteriophage from
Bacillus stearothermophilus
. J. Bacteriol.
89:
175–184. 1965.—
Bacillus stearothermophilus
1503-4R growing at 55 C was induced to lyse either when 0.05 μg/ml of mitomycin C was added or when it was exposed to ultraviolet light for 30 sec. Lysis of the induced cultures occurred 45 to 60 min after induction. Phage were assayed on
B. stearothermophilus
4S giving turbid plaques 0.05 to 0.3 cm in diameter. Noninduced cultures of 1503-4R spontaneously produced one phage per 2.8 × 10
6
bacterial cells. The optimal temperature for phage production and assay was found to be 55 C.
B. stearothermophilus
1503-4R was immune to the isolated temperate phage (TP-1) and to a clear-plaque mutant phage (TP-1C), even when tested at phage mutliplicities of 100. TP-1 and TP-1C phage were identical morphologically having a head 65 mμ in diameter and a tail 240 mμ long and 12 mμ wide. TP-1C phage deoxyribonucleic acid (DNA) had an
S
20,w
value of 24.1 and a calculated molecular weight of 1.21 × 10
7
. DNA base compositions of TP-1 and TP-1C phage were identical (42% guanine + cytosine), but differed significantly from those of the lysogenic or indicator strains of
B. stearothermophilus
(50% guanine + cytosine). No unusual bases were detected in either the bacterial or phage DNA.
Biochemical and Genetic Grouping of Isoleucine-Valine Mutants of
Pseudomonas aeruginosa
Authors: Pearce L. E. , Loutit J. S.
Published: January 2020

Pearce
, L. E. (University of Otago, Dunedin, New Zealand),
and J. S. Loutit
. Biochemical and genetic grouping of isoleucine-valine mutants of
Pseudomonas aeruginosa
. J. Bacteriol.
89:
58–63. 1965.—Isoleucine- and valine-requiring mutants of
Pseudomonas aeruginosa
, induced with ultraviolet and ethyl-methane-sulfonate, were isolated. The feeding properties and growth requirements of 56 of these mutants were examined, and evidence was found for at least four phenotypic groups, A, B, C, and D, controlling the biosynthesis of isoleucine and valine. Preliminary genetic mapping by use of bacteriophage-mediated transduction showed linkage between the mutant loci within groups A, B, and C. There was also evidence of linkage between the genes controlling groups A and B and some slight evidence of linkage between the other groups. There was insufficient evidence to suggest the arrangement of the genes.
Intracellular Fate of Mengo Virus Ribonucleic Acid
Authors: Homma M. , Graham A. F.
Published: January 2020

Homma
, M. (The Wistar Institute, Philadelphia, Pa.),
and A. F. Graham
. Intracellular fate of Mengo virus ribonucleic acid. J. Bacteriol.
89:
64–73. 1965.—P
32
-labeled, purified preparations of Mengo virus adsorbed rapidly and irreversibly to L cells maintained in suspension cultures. At intervals after adsorption of labeled virus, the total ribonucleic acid (RNA) of infected cells was extracted by a phenol technique. Infectivity titrations on this RNA showed that it retained its full biological activity during the early part of the eclipse period. Sucrose gradient sedimentation analyses showed also that this RNA lost none of its structural integrity throughout the eclipse period. No evidence was found for a double-stranded structure involving parental RNA. When cells infected with P
32
-labeled virus were broken open during the first 7 hr after infection, no more than 20% of the parental RNA could be digested with ribonuclease. Electron microscopy indicated that only one particle in five of the purified viral populations was infectious. It is suggested that only one of five adsorbed virus particles was uncoated and that its RNA remained in the cell in an undegraded form during the eclipse period. The other adsorbed particles were not uncoated and took no part in the process of infection. The maximal transfer of parental RNA to progeny virus was 4.5%.
“Genetic Species” Concept in
Xanthomonas
Authors: Friedman S. , De Ley J.
Published: January 2020

Friedman
, S. (State University, Ghent, Belgium),
and J. De Ley
. “Genetic species” concept in
Xanthomonas
. J. Bacteriol.
89:
95–100. 1965.—Deuterated, N
15
-labeled deoxyribonucleic acid (DNA) from
Xanthomonas pelargonii
forms distinct hybrids with ordinary DNA from
X. hederae, X. juglandis
, and
X. carotae
. Hybridization is less pronounced with
X. phaseoli
and
X. begoniae
. There is evidence that some hybridization occurs with
X. vesicatoria, X. campestris
, and
X. tamarindi
. These results favor the concept of a “genetic species,” rather than a division of the genus into many separate species based almost entirely on phytopathogenic host specificity.
Nature of Butyrate Oxidation by
Mycoplasma hominis
Authors: VanDemark P. J. , Smith P. F.
Published: January 2020

VanDemark
, P. J. (Cornell University, Ithaca, N.Y.),
and P. F. Smith
. Nature of butyrate oxidation by
Mycoplasma hominis
. J. Bacteriol.
89:
373–377. 1965.—Cell-free extracts of butyrate - grown
Mycoplasma hominis
strain O7, though lacking thiokinase activity on butyric acid, were found to activate butyrate via an acetyl-butyric thiophorase. These extracts also contained an aceto-coenzyme A (CoA) kinase, a butyryl-CoA dehydrogenase, a crotonase, a reduced nicotinamide adenine dinucleotide-specific β-hydroxybutyryl-CoA dehydrogenase, and a thiolase. Thiolase activity was stimulated by the addition of magnesium ions. The presence of these enzyme activities in this
Mycoplasma
species supports the hypothesis that a fatty acid oxidation represents an energy source for the nonfermentative pleuropneumonia-like organisms.
Fine Structure of
Rickettsia quintana
Cultivated In Vitro and in the Louse
Authors: Ito Susumu , Vinson J. W.
Published: January 2020

Ito, Susumu
(Harvard Medical School, Boston, Mass.),
and J. W. Vinson
. Fine structure of
Rickettsia quintana
cultivated in vitro and in the louse. J. Bacteriol.
89:
481–495. 1965.—Usually rod-shaped,
Rickettsia quintana
cells measure about 0.2 to 0.5 μ wide and up to 1.6 μ long. The rickettsiae have both an outer cell wall, about 80 A thick, and a plasma membrane, about 70 A thick, each of which is trilaminar. Occasional vesicular invaginations of the plasma membrane occur. The nuclear material, distributed in irregular zones throughout the cytoplasm, appears as a loose network of fine fibrils when postfixed with uranyl acetate and as thick strands or clumps after routine OsO
4
fixation. The cytoplasm is densely packed with numerous granules, presumably ribosomes, about 150 A in diameter. Histochemical studies revealed the presence of both ribonucleic and deoxyribonucleic acids. During binary fission, a constricting furrow is formed by the cell wall and plasmalemma. No difference in fine structure was observed between
R. quintana
propagated on cell-free media and in the louse.
Uptake of Griseofulvin by the Sensitive Dermatophyte,
Microsporum gypseum
Authors: El-Nakeeb Moustafa A. , Lampen J. O.
Published: January 2020

El-Nakeeb, Moustafa
A. (Rutgers, The State University, New Brunswick, N.J.),
and J. O. Lampen
. Uptake of griseofulvin by the sensitive dermatophyte,
Microsporum gypseum
. J. Bacteriol.
89:
564–569. 1965.—Actively growing cultures of
Microsporum gypseum
took up large amounts of griseofulvin-(4-methoxy-H
3
) from the medium. Initially, most of the material could be extracted with hot water, but there was a continuing increase in firmly bound forms of the antibiotic. The fungus accumulated griseofulvin intracellularly to a level up to 100 times that present in the medium. The process appeared to involve two phases. A small amount of griseofulvin was bound almost instantaneously. This binding was independent of the culture conditions or cell viability. The second stage was prolonged and was governed by the different factors controlling active metabolism, but it proceeded in organisms whose growth had been inhibited by the antibiotic itself or by limited nutrients. This stage required a supply of metabolic energy, since it was temperature-dependent, needed an exogenous energy source, and was completely inhibited by sodium azide or 2,4-dinitrophenol. Uptake was optimal at
p
H 5.5 to 6.5. Synthesis of a transport system is probably required, since uptake is prevented by
p
-fluorophenylalanine. Heat-killed cells did not take up griseofulvin beyond the small amount bound instantly.
Regulatory Mechanisms in the Biosynthesis of Isoleucine and Valine III. Map Order of the Structural Genes and Operator Genes
Authors: Ramakrishnan T. , Adelberg Edward A.
Published: January 2020

Ramakrishnan
, T. (Yale University, New Haven, Conn.),
and Edward A. Adelberg
. Regulatory mechanisms in the biosynthesis of isoleucine and valine. III. Map order of the structural genes and operator genes. J. Bacteriol.
89:
661–664. 1965.—A new method has been employed to determine the map order of the structural genes and operator genes governing the enzymes of the isoleucine-valine biosynthetic pathway. This method relies on the observation that phage transduction of markers carried on an F-genote leads to the establishment in the recipient of F-genotes of various lengths. Using this method, we have established that the order of loci is the following:
F/ilvE ilvD ilvA oprA/ilvC/ilvB oprB
. The operator locus,
oprA
, regulates the activity of structural genes
ilvE
(transaminase B),
ilvD
(dehydrase), and
ilvA
(threonine deaminase). The operator locus,
oprB
, regulates the activity of
ilvB
(condensing enzyme). An operator for
ilvC
(reductoisomerase) can be inferred to exist, but has not yet been detected genetically. The loci
ilvB
and
oprB
have been shown to be at the extreme right end of the sequence, but their positions relative to each other remain to be established.
Effect of Hemin on the Formation of the Cytochrome System of Anaerobically Grown
Staphylococcus epidermidis
Authors: Jacobs N. J. , Conti S. F.
Published: January 2020

Jacobs
, N. J. (Dartmouth Medical School, Hanover, N.H.),
and S. F. Conti
. Effect of hemin on the formation of the cytochrome system of anaerobically grown
Staphylococcus epidermidis
. J. Bacteriol.
89:
675–679. 1965.—The cytochrome content and respiratory capacity of cells of a strain of
Staphylococcus epidermidis
grown in complex media under aerobic and anaerobic conditions were determined. Difference spectra revealed cytochromes of the
a, b
1
, and
o
types in aerobically grown cells. These cells respired at a rate of 66 μliters of O
2
per hr per mg of cells (dry weight). The cytochrome content of anaerobically grown cells was markedly reduced, and trace amounts only of cytochromes of the
b
1
and
o
type were visible. The respiratory rate, with glucose as substrate, was reduced to about one-tenth of that observed in aerobically grown cells. Cells grown anaerobically in medium supplemented with hemin had as high a content of pigments resembling cytochromes
b
1
and
o
as did aerobically grown cells; the respiratory rate was 60% of that observed in aerobically grown cells. Cytochrome of the
a
type, similar to that found in aerobically grown cells, was not detected.
Factors Affecting the Rate of Killing ofEscherichia coliby Repeated Freezing and Thawing
Authors: Packer Elliot L. , Ingraham John L. , Scher Stanley
Published: January 2020

Packer, ElliotL. (University of California, Davis),John L. Ingraham, and Stanley Scher. Factors affecting the rate of killing ofEscherichia coliby repeated freezing and thawing. J. Bacteriol.89:718–724. 1965.—Repeated freezing and thawing of cultures ofEscherichia coligrown in a minimal medium and frozen in the same medium without carbon source resulted in a linear decrease in the log of the number of surviving cells as a function of the number of freeze-thaw cycles. The slope of this curve, which can be determined accurately, is an index of susceptibility of a culture to death by freezing and thawing. The effect of the physiological state of the culture on the killing rate was determined. Contrary to previous reports, the phase of growth, the state of aerobiosis, and the density of the culture had no effect on the degree of susceptibility to death by freezing and thawing. However, presence of spent growth medium (a filtrate of a stationary culture) in the freezing medium protected cells against death by freezing and thawing. Protection by spent growth medium is effective at high dilutions (1:105), and is lost if spent growth medium is heated in the presence of alkali. It is suggested that the protection afforded by spent growth medium accounts for differences between our results and those reported in the literature.
Replication of
Mycoplasma pneumoniae
in Broth Culture
Authors: Low Iolanda E. , Eaton Monroe D.
Published: January 2020

Low, Iolanda
E. (Harvard Medical School, Boston, Mass.),
and Monroe D. Eaton
. Replication of
Mycoplasma pneumoniae
in broth culture. J. Bacteriol.
89:
725–728. 1965.—Reproducible growth curves of
Mycoplasma pneumoniae
can be obtained with the use of shaking cultures, which allows earlier and higher yields of the organism than stationary or roller cultures. Decreasing oxygen tension clearly decreases the growth of
M. pneumoniae
to barely detectable levels, with or without glucose or pyruvate as substrates. The use of phenol red as a
p
H indicator in the medium is helpful in judging the replication of a culture so that log-phase organisms can be harvested in large amounts.
Bacteriophage Deoxyribonucleate Infection of Competent
Bacillus subtilis
Authors: Reilly Bernard E. , Spizizen John
Published: January 2020

Reilly, Bernard
E. (Western Reserve University, Cleveland, Ohio),
and John Spizizen
. Bacteriophage deoxyribonucleate infection of competent
Bacillus subtilis
. J. Bacteriol.
89:
782–790. 1964.—Phenol extracts of the
Bacillus subtilis
bacteriophages φ1, φ25, and φ29 contained infectious deoxyribonucleic acid. The infectivity was destroyed by catalytic amounts of deoxyribonuclease but not by specific phage antiserum, ribonuclease, or trypsin. An infectivity of >10
6
infectious centers formed per μg of deoxyribonucleic acid (DNA) added was obtained. The stability of the infectious centers permitted an examination of a single cycle of phage replication in cells unable to adsorb the mature virus. A typical cycle was observed, although the latent period was increased and the burst size slightly reduced after DNA infection. The development of competence for bacterial transformation was strongly correlated with susceptibility to viral DNA infection. Both appeared and disappeared at the same phase of growth in the cell population. More than 4% of the viable cells in the competent population were infected by viral DNA. The kinetics of the transition of φ29 DNA infection to deoxyribonuclease insensitivity, and the relationship of infectivity to DNA dilution, were similar to the results obtained for bacterial transformation of a single marker. The doseresponse curve of φ1 and φ25 DNA was characteristic of that obtained in multiple transformation of unlinked genetic markers. Because of the low efficiency of infection, about 10
−4
per phage equivalent of DNA added, it was not possible to prove that DNA alone was sufficient to initiate infection.
Characteristics and Intermediates of Short-Term C
14
O
2
Incorporation During Ribose Oxidation by
Hydrogenomonas facilis
Authors: McFadden Bruce A. , Homann H. Robert
Published: January 2020

McFadden
, B. A. (Washington State University, Pullman),
and H. R. Homann
. Characteristics and intermediates of short-term C
14
O
2
incorporation during ribose oxidation by
Hydrogenomonas facilis
. J. Bacteriol.
89:
839–847. 1965.—Ribose-grown cells of
Hydrogenomonas facilis
, which had been suspended in growth medium and were oxidizing ribose, were exposed to HC
14
O
3
−
of high specific activity. The uptake was proportional to cell mass. Short-term uptake (less than 2 min) was completely inhibited by 10
−3
m
2,4-dinitrophenol (DNP) or by <4 × 10
−6
m
m
-chlorocarbonyl cyanide phenylhydrazone, and to the extent of 42% by 5 × 10
−5
m
DNP. The following observations were made in kinetic studies (8, 16, 35, 67, 96, and 181 sec) of fixation in the presence of ribose. Glutamate was extensively labeled in periods up to 3 min. It was one of the major early products, containing 30% of the label at 8 sec. The sugar phosphate fraction was not detectably labeled at 8 or 16 sec, but its C
14
-content increased rapidly to 27% at 35 sec and then slowly decreased. Label in phosphoglycerate, phosphoenolpyruvate, and alanine did not appear until 35 sec, and did not exceed about 7, 2, and 3%, respectively, of the total extracted radioactivity. Adenosine triphosphate and adenosine diphosphate were heavily labeled after fixation in a pilot study for 125 sec. Although considerable radioactivity incorporated during the pilot study was intractable by the extraction procedure employed, virtually no C
14
was found in the residue in poly-β-hydroxybutyric acid. A large number of amino acids and organic acids and some organic phosphates were not detectably labeled in any of the experiments. Omission of ribose greatly diminished incorporation, particularly into glutamate.
Ultraviolet-Absorption Spectra of Dry Bacterial Spores
Authors: Bailey Glen F. , Karp Saima , Sacks L. E.
Published: January 2020

Bailey, Glen
F. (Western Regional Research Laboratory, Albany, Calif.),
Saima Karp, and L. E. Sacks
. Ultraviolet-absorption spectra of dry bacterial spores. J. Bacteriol.
89:
984–987. 1965.—The possibility of obtaining reasonably satisfactory ultraviolet-absorption spectra of dry spores embedded in KBr has been demonstrated. Such spectra show the three peaks characteristic of calcium dipicolinate. The dipicolinate spectra are more distinct when reference pellets containing appropriate amounts of the analogous spore coats are employed. These spectra are considered evidence that some type of calcium-dipicolinic acid chelate accounts for at least part of the calcium and dipicolinic acid content of the spore.
Enzymatic Basis for
d
-Arabitol Production by
Saccharomyces rouxii
Authors: Ingram Jordan M. , Wood W. A.
Published: January 2020

Ingram, Jordan
M. (Michigan State University, East Lansing),
and W. A. Wood
. Enzymatic basis for
d
-arabitol production by
Saccharomyces rouxii
. J. Bacteriol.
89:
1186–1194. 1965.—The enzymatic steps in
d
-arabitol synthesis by
Saccharomyces rouxii
were studied. The fermentation of
d
-glucose-
6-C
14
gave rise to
d
-arabitol labeled at C-5;
d
-ribose of ribonucleic acid had the same isotope pattern. Crude extracts were able to reduce
d
-ribulose with reduced nicotinamide adenine dinucleotide phosphate (NADPH
2
) and
d
-xylulose with reduced nicotinamide adenine dinucleotide (NADH
2
). These extracts also oxidized
d
-arabitol with nicotinamide adenine dinucleotide phosphate and xylitol with nicotinamide adenine dinucleotide. No reduction of
d
-ribulose-5-phosphate or
d
-xylulose-5-phosphate was observed. An enzyme which reduced
d
-xylulose with NADH
2
was purified 33-fold and characterized as a xylitol (→
d
-xylulose) dehydrogenase. Similarly, an enzyme reducing
d
-ribulose with NADPH
2
was purified 12-fold and characterized as a
d
-arabitol (→
d
-ribulose) dehydrogenase. Alkaline and acid phosphatases were purified 50- and 40-fold, respectively, and their specificities were determined. Only the acid phosphatase had detectable activity on
d
-ribulose-5-phosphate. The data support the postulate that
d
-arabitol arises by dephosphorylation of
d
-ribulose-5-phosphate and reduction of
d
-ribulose by a NADPH
2
-linked
d
-arabitol (→
d
-ribulose) dehydrogenase.
Effect of Light Intensity on the Formation of Intracytoplasmic Membrane in
Rhodospirillum rubrum
Authors: Holt Stanley C. , Marr Allen G.
Published: January 2020

Holt, Stanley
C. (University of California, Davis),
and Allen G. Marr
. Effect of light intensity on the formation of intracytoplasmic membrane in
Rhodospirillum rubrum
. J. Bacteriol.
89:
1421–1429. 1965.—Cells of
Rhodospirillum rubrum
grown at low light intensity were found to contain much more internal membrane than cells grown at high light intensity. Highly purified membranes (chromatophores) from cells grown at low to moderate light intensity had a constant content of chlorophyll. Thus, the regulation of the chlorophyll content of the cell depends upon the formation of greater or lesser amounts of membrane which has a constant concentration of chlorophyll.
Protection of Measles Virus by Sulfate Ions Against Thermal Inactivation
Authors: Rapp Fred , Butel Janet S. , Wallis Craig
Published: January 2020

Rapp, Fred(Baylor University College of Medicine, Houston, Tex.),Janet S. Butel, and Craig Wallis. Protection of measles virus by sulfate ions against thermal inactivation. J. Bacteriol.90:132–135. 1965.—The infectivity of measles virus in water is rapidly destroyed at temperatures of 37 C and above. More than 50% of the infectivity is lost after 1 hr at 25 C, and almost 90% loss of infectivity occurs within 24 hr at 4 C. Magnesium chloride enhances the inactivation of the virus at all temperatures tested. Addition of either magnesium or sodium sulfate protects the virus against thermal inactivation. The stabilizing effect is demonstrable at temperatures ranging from 4 to 56 C, but is especially pronounced through 45 C. Prolonged storage (up to 6 weeks) of the virulent virus at 4 C in 1mmagnesium sulfate permits retention of substantial infectivity, whereas storage at 4 C in either water or 1mmagnesium chloride results in a loss of infectivity approximating 99% after 2 weeks. Magnesium chloride also enhances inactivation of the attenuated vaccine strain of measles virus. The attenuated virus, however, is strongly protected by magnesium sulfate against thermal inactivation, and retention of infectivity for long periods of time at 4 C seems feasible when the virus is kept in 1mmagnesium sulfate.
Truncated Glycolytic System in
Veillonella
Authors: Rogosa M. , Krichevsky M. I. , Bishop F. S.
Published: January 2020

Rogosa
, M., (National Institutes of Health, Bethesda, Md.), M. I.
Krichevsky, and F. S. Bishop
. Truncated glycolytic system in
Veillonella
. J. Bacteriol.
90:
164–171. 1965.—Intact
Veillonella
cells do not utilize carbohydrates for growth, nor are carbohydrates fermented. In cell extracts, there is no detectable glucokinase or fructokinase. Cell extracts do not degrade glucose or fructose unless supplemented with yeast hexokinase. Under these conditions, triose phosphates are formed in the presence of a hydrazine trap. When glucose-C
14
plus added hexokinase or fructose-1,6-diphosphate-C
14
was incubated with cell extracts, the production of CO
2
, acetate, pyruvate, propionate, and lactate was detected. It is concluded that, except for a hexokinase, all the activities required for a glycolytic system are present.
Structure and Composition of a Small Particle Prepared from a Simian Adenovirus
Authors: Mayor Heather D. , Jamison Richard M. , Jordan Liane E. , Melnick Joseph L.
Published: January 2020

Mayor, Heather
D. (Baylor University College of Medicine, Houston, Tex.),
Richard M. Jamison, Liane E. Jordan, and Joseph L. Melnick
. Structure and composition of a small particle prepared from a simian adenovirus. J. Bacteriol.
90:
235–242. 1965.—When tissue-culture fluids infected with simian adenovirus SV15 are examined in an electron microscope, either as fresh harvests or after treatment with Genetron, typical mature adenovirus particles are found. These are 65 to 70 mμ in diameter, with an icosahedral capsid built from 252 capsomeres. Also present is a population of small polyhedral particles approximately 20 mμ in diameter. These small particles can be separated from the mature virions by ultrafiltration or density gradient centrifugation. The small particles have a density of 1.43 in cesium chloride. They contain protein and double-stranded deoxyribonucleic acid. They appear to possess cubic symmetry of the icosahedral type, with a coat composed of 12 subunits each at the vertex of an icosahedron.
Localization of Somatic Antigen on Gram-Negative Bacteria by Electron Microscopy
Authors: Shands J. W.
Published: January 2020

Shands, J. W. (University of Florida, Gainesville). Localization of somatic antigen on gram-negative bacteria by electron microscopy. J. Bacteriol.90:266–270. 1965.—Antisera specific for the somatic antigens ofSalmonella typhimuriumandEscherichia coliO113 were prepared, and globulins isolated from these antisera were labeled with ferritin. Micrographs of labeled, sectioned bacteria show that somatic antigen is located in considerable quantities on the surface of the bacteria, and, furthermore, that it can extend up to 150 mμ beyond the confines of the cell wall. The arrangement of the ferritin on the bacteria suggests that the antigenic sites are located on fibrillar structures.
Characteristics of
Mycoplasma meleagridis
sp. n., Isolated from Turkeys
Authors: Yamamoto R. , Bigland C. H. , Ortmayer H. B.
Published: January 2020

Yamamoto
, R. (University of California, Davis), C. H.
Bigland, and H. B. Ortmayer
. Characteristics of
Mycoplasma meleagridis
sp. n., isolated from turkeys. J. Bacteriol.
90:
47–49. 1965.—A designation is proposed for a pathogenic
Mycoplasma
species isolated from turkeys. The organism originally was recovered from the air-sac lesion of a turkey poult in 1957, and was designated the “N” strain.
Mycoplasma
species with identical characteristics have since been recovered from the sinus, trachea, oviduct, vagina, semen, and bursa of Fabricius of turkeys. The organism has been recovered from many turkey flocks throughout the country. Many investigators have confirmed the original finding that this organism is antigenically distinct from other known serotypes of
Mycoplasma
found in poultry. The species proposed is
Mycoplasma meleagridis
sp. n.