bluuebunny/crossref_metadata_2025 huggingface dataset:
Preservation of Mycobacteria: 100% Viability of Suspensions Stored at -70 C
Authors: Kim Thomas H. , Kubica George P.
Published: December 2020

Our earlier studies on long-term preservation of mycobacteria have been expanded to include other species in this genus.
Mycobacterium kansasii
and
M. marinum
, like mammalian tubercle bacilli and BCG, survive much better when stored at -70 C. By statistical analysis,
M. gordonae, M. scrofulaceum, M. xenopi, M. avium, M. intracellulare, M. terrae, M. fortuitum
, and
M. smegmatis
survived equally well at -20 C or -70 C; however, viable counts of all strains stored at -20 C were always lower than those of paired suspensions stored at -70 C, suggesting that the lower temperature is preferable for prolonged storage periods. Advantages of preservation at -70 C in Tween-albumin liquid medium are: (i) 100% viability of bacterial populations for long periods, (ii) highly reproducible inocula for animal experiments, (iii) minimal clonal selection of undesirable mutants, (iv) maintenance of genetic characteristics, and (v) adaptability to a “seed lot” system. On the basis of available information, a discussion of lyophilization versus freezer storage is presented.
Utilization of Iron Gallate and Other Organic Iron Complexes by Bacteria from Water Supplies
Authors: Rae I. C. Mac , Edwards J. F. , Davis Nour
Published: December 2020

The degradation of four soluble organic iron compounds by bacteria isolated from surface waters and the precipitation of iron from these complexes by the isolates was studied. All eight isolates brought about the precipitation of iron when grown on ferric ammonium citrate agar. Three isolates were able to degrade ferric malonate, and three others degraded ferric malate with iron precipitation. Only three isolates, two strains of
Pseudomonas
and one of
Moraxella
, were able to degrade gallic acid when this was supplied as the sole carbon source. One strain of
Pseudomonas
was found to be active in degrading ferric gallate. Electron microscopy of cells of this bacterium after growth in ferric gallate as the sole carbon source yielded results indicating uniform deposition of the iron on or in the bacterial cells. Seven of the isolates could degrade the iron gallate complex if supplied with additional carbon in the form of yeast extract.
Assay Methods for
Clostridium perfringens
Type A Enterotoxin
Authors: Genigeorgis C. , Sakaguchi G. , Riemann H.
Published: December 2020

Enterotoxin produced by a sporulating culture of
Clostridium perfringens
type A NCTC 8798 was purified to a level of 3,500 mouse mean lethal doses per mg of nitrogen. High-titer sera were obtained from rabbits injected with enterotoxin and used to compare the sensitivity of serological tests and bioassays for
C. perfringens
enterotoxin. Reversed passive hemagglutination was by far the most sensitive test, followed by microslide diffusion, single gel diffusion and electroimmunodiffusion, guinea pig skin test, mouse test, and rabbit ileal loop test.
Simplified Method for Producing Pyocins from
Pseudomonas aeruginosa
Authors: Jones Lois F. , Pinto B. V. , Thomas Evan T. , Farmer J. J.
Published: December 2020

Good yields of pyocin are obtained when
Pseudomonas aeruginosa
is grown in Trypticase soy broth (without glucose) (BBL) plus 1% potassium nitrate. As a result, pyocin production for routine epidemiological typing can be done in screw-cap tubes, without mechanical agitation or mitomycin C induction.
Oxidation of 1-Alkenes to 1,2-Epoxyalkanes by
Pseudomonas oleovorans
Authors: Abbott Bernard J. , Hou Ching T.
Published: December 2020

Resting cells of
Pseudomonas oleovorans
PO-1R that had been grown on octane oxidized 1-alkenes containing 6 to 12 carbon atoms and 1,7-octadiene to their corresponding 1,2-epoxides. The microorganism was capable of growing on 1-octene but not on 1,7-octadiene as a sole carbon source. The optimal temperature, pH, and 1-octene concentration for 1,2-epoxyoctane production by the resting cells were 34 to 40 C, pH 7 to 8, and 1.5 mg of 1-octene per ml, respectively. Epoxide concentration reached a maximum after 150 min of incubation and subsequently declined. In the absence of 1-octene, the epoxide was metabolized readily by the resting cells. The amount of 1,2-epoxyoctane produced was dependent on the initial cell concentration. With larger cell populations, the amount of epoxide present after 60 min of incubation was less than the amount observed at lower population densities after the same time period. This relationship was attributed to the rapid depletion of 1-octene at high biomass concentrations and the resultant early initiation of epoxide degradation by the resting cells.
Erysipelas Serum Titration with Sheep Red Blood Cells Passively Sensitized with a Cellular Extract
Authors: Poole George M. , Counter Fred T.
Published: December 2020

We have demonstrated that sheep red blood cells can be passively sensitized with an extract from
Erysipelothrix rhusiopathiae
. Diagnostic differential hemagglutination titrations may then be made with porcine serum for Erysipelas antibody.
Rapid Method for Detection of
Pseudomonas aeruginosa
on MacConkey Agar Under Ultraviolet Light
Authors: Brodsky M. H. , Nixon M. C.
Published: December 2020

A simple screening technique for the detection of
Pseudomonas aeruginosa
colonies by their fluorescence on MacConkey agar under ultraviolet light is proposed. From 306 nonlactose fermenting cultures screened under the ultraviolet light, 108 fluorescent isolates were obtained. These were screened biochemically, with 103 (94.8%) being verified as
P. aeruginosa
. From the 198 nonfluorescing cultures, only one suspected
P. aeruginosa
was isolated.
Specific Immunodiffusion Test for Blastomycosis
Authors: Kaufman Leo , McLaughlin David W. , Clark Maxine J. , Blumer Sharon
Published: December 2020

A specific immunodiffusion test for blastomycosis has been developed. The test permitted the detection of approximately 80% of 113 proven cases of blastomycosis. Two diagnostically important precipitins designated A and B were frequently recognized in patients with blastomycosis. Routine use of reference sera containing the A and B precipitins in immunodiffusion tests would permit the specific diagnosis of blastomycosis without the need for parallel tests with coccidioidin and histoplasmin.
Interaction of Some Factors in the Mechanism of Inactivation of Bacteriophage MS2 in Aerosols
Authors: Trouwborst T. , De Jong J. C.
Published: December 2020

The mechanisms involving inactivation of bacteriophage MS2 in aerosols and the effect of protective substances in the spray-medium were studied after spraying from various NaCl solutions. Results with aerosols generated from the salt solutions showed that with higher salt concentration in the spray-medium higher concentrations of protective substances were needed to protect phage MS2 against aerosol inactivation. Phenylalanine, which has a protective action at low concentration, produced less protection in aerosol droplets that were supersaturated solutions of this substance or in which crystals of phenylalanine can be expected to form. Our results suggested that protection by peptone and phenylalanine was related to the concentration in the aerosol droplet after evaporation to equilibrium, whereas protection by the surface active agent OED (a commercial mixture of oxyethylene docosylether and oxyethelene octadecylether) was related to the concentration at which a monolayer is formed around the aerosol particle. Inactivation of phage MS2 was maximal in the aerosol particle in fluid phase and became less at lower relative humidity where aerosol particles are expected to be in the solid state. It is suggested that inactivation of bacteriophage MS2 in aerosols could be explained by surface inactivation at the air-water interface.
Suppression of Herpes Simplex Virus Infection by Phosphonoacetic Acid
Authors: Shipkowitz N. L. , Bower R. R. , Appell R. N. , Nordeen C. W. , Overby L. R. , Roderick W. R. , Schleicher J. B. , Von Esch A. M.
Published: December 2020

Disodium phosphonoacetate when administered orally or topically to mice experimentally infected with herpes simplex virus was able to significantly reduce the mortality associated with the agent. In addition, this compound was able to reduce herpesvirus lesions on the corneas of infected rabbits.
Inactivation of
Clostridium perfringens
Type A Spores at Ultrahigh Temperatures
Authors: Adams D. M.
Published: December 2020

The inactivation of
Clostridium perfringens
type A spores (three strains of different heat resistances) at ultrahigh temperatures was studied. Aqueous spore suspensions were heated at 85 to 135 C by the capillary tube method. When survivors were enumerated on the standard plating medium, the spores appeared to have been rapidly inactivated at temperatures above 100 C. The addition of lysozyme to the plating medium did not affect the recovery of spores surviving the early stages of heating, but lysozyme was required for maximal recovery of spores surviving extended heat treatments. The percentage of survivors requiring lysozyme for colony formation increased greatly with longer exposure times or increasing treatment temperature. Time-survivor curves indicated that each spore suspension was heterogeneous with respect to the heat resistance of spore outgrowth system or in the sensitivity of the spores to lysozyme. Recovery of survivors on the lysozyme containing medium revealed greater heat resistance for one strain than has been reported for spores of many mesophilic aerobes and anaerobes. The spores of all three strains were more resistant to heat inactivation when suspended in phosphate buffer, but a greater percentage of the survivors required lysozyme for colony formation.
Computer Identification of Bacteria on the Basis of Their Antibiotic Susceptibility Patterns
Authors: Friedman Richard , MacLowry James
Published: December 2020

A computer program utilizing a Baysean mathematical model was developed to identify bacteria solely on the basis of their antibiotic sensitivities. The model contains probability data on the antibiotic sensitivity patterns for 31 species of bacteria, which account for over 99% of all isolates submitted to our laboratory for testing. During a 4-month test period, antibiotic sensitivity data on 1,000 clinical isolates were processed by the program. The identification achieved by using the model was the same as that of the laboratory for over 86% of the isolates.
Production of the Hepatotoxic Chlorine-Containing Peptide by
Penicillium islandicum
Sopp
Authors: Ishii Kenji , Ueno Yoshio
Published: December 2020

Twenty-six strains of
Penicillium islandicum
Sopp were tested for production of a chlorine-containing peptide (Cl-peptide), which is a hepatotoxin. Highest levels of the mycotoxin were produced in a modification of Wickerham medium. The mycotoxin was isolated by adsorption on charcoal and, after washing the charcoal with acetone-water (1:1), was eluted into
n
-butanol. Further purification was accomplished by gel filtration. Maximum yields were 10 to 20 mg of toxin per liter of culture filtrate.
Rodac Plate-Holding Device for Sampling Surfaces During Surgery
Authors: Hart Jack B. , French Morris L. V. , Eitzen Harold E. , Ritter Merrill A.
Published: December 2020

A Rodac plate-holding device has been developed to facilitate microbial surface sampling of supposedly sterile items in the operating room during surgery.
Pyridine Extraction of Nocardial Acid Fastness
Authors: Beaman B. L. , Burnside J.
Published: December 2020

Several strains of
Mycobacterium
and
Nocardia
were stained for acid fastness by using the method of Kinyoun. Duplicate, glutaraldehyde-fixed smears were extracted with fresh pyridine prior to staining. The results clearly demonstrated that both in vivo- and in vitro-grown
Nocardia
differed from
Mycobacterium
by becoming nonacid fast after extraction. This pyridine extraction of nocardial acid fastness should have diagnostic and taxonomic application.
Isolation and Characterization of Corynebacteria from Burned Children
Authors: Smith Rodney F. , Blasi Dianna , Dayton Sandra L.
Published: December 2020

A total of 221 strains of corynebacteria were isolated and characterized by methods which included tests encompassing five schemes proposed for grouping cutaneous diphtheroids. Seventy-one strains (group I) were isolated from the hospital air in patient areas and from the normal skins of children admitted for reconstructive surgery of old healed burns and from the normal skins of nursing personnel. One hundred and fifty strains (group II) were isolated from various clinical specimens and from normal skins of a population of acutely burned children. The majority of the strains in group I were lipophilic and contained the largest number of fluorescent strains. Among the group II strains, there was a subgroup which was nonsusceptible to oxacillin, lincomycin, erythromycin, and kanamycin and also had in common the fermentation of glucose and galactose, reduction of both nitrate and nitrite, and growth on 40% bile agar. These strains were the most commonly recognized types isolated from acutely burned patients and possibly originated from the patient's intestinal tract. Data indicated that the air was not a means of transmission for these corynebacteria among acute patients. Corynebacteria were isolated from 11% of the burn wound cultures by using a selective medium but were found in 66% of the acute patients. Over 90% of the strains in groups I and II did not conform sufficiently with described characteristics of common human indigenous corynebacteria to be accurately speciated.
Complement-Fixation Analysis of Four Subtypes of Foot-and-Mouth Disease Virus Type A
Authors: Lobo C. A. , Cowan K. M. , Hanson R. P.
Published: December 2020

Complement-fixation patterns were established for four subtypes of foot-and-mouth disease virus by block assays against homologous and heterologous antiserum. Inhibition of fixation by excess antigen was observed in most homologous systems but rarely in the heterologous systems. The heterologous antibody titers were, in all instances, considerably lower than those for the homologous systems. Although relatively high dilutions of antiserum may be desirable for subtyping, higher concentrations of antibody should be used for determining serological types.
Bacteriological Survey of Frozen Meat and Gravy Produced at Establishments Under Federal Inspection
Authors: Surkiewicz Bernard F. , Harris Marshall E. , Johnston Ralph W.
Published: December 2020

During visits to 34 federally inspected establishments producing frozen meat and gravy, 541 production line samples and 535 finished product units were collected for bacteriological analyses. It was found that more than 70% of the sets of finished product (10 units/set) produced under good manufacturing practices had: (i) four or fewer coliform-positive units, (ii) two or fewer
Escherichia coli
-positive units, (iii) three or fewer
Staphylococcus aureus
-positive units, and (iv) an aerobic plate count of fewer than 50,000/g (geometric mean of 10 units). All finished product units were negative for salmonellae.
Microbiological Study of Streptococcal Bacteremia
Authors: Horstmeier Carlyle , Washington John A.
Published: December 2020

During a 2.5-year study, streptococci were isolated from 280 patients (19% of those with bacteremia). Of this number, 54 had group D streptococci (45 were enterococci), 218 had α- or γ-hemolytic nongroup D streptococci, and 49 had β-hemolytic streptococci.
Influence of Milk Components on the Injury, Repair of Injury, and Death of
Salmonella anatum
Cells Subjected to Freezing and Thawing
Authors: Janssen D. W. , Busta F. F.
Published: December 2020

Fast freezing and slow thawing
Salmonella anatum
cells in various milk components inactivated from 20 to 98% of the cells and damaged 40 to 90% of the cells surviving the treatments. Injured cells failed to form colonies on a selective medium (xylose-lysine-peptone agar with 0.2% sodium deoxycholate) but did form colonies on a nonselective plating medium (xylose-lysine-peptone agar). The major milk components—lactose, milk salts, casein, and whey proteins—influenced the extent of injury, repair of injury, and death. The percentages of cells injured and inactivated were decreased by the presence of any milk components except whey proteins. Also, repair of injury was promoted by the presence of each milk component except whey proteins, which in contrast inhibited repair. Phosphate was the most influential milk salts component that protected the cells and promoted repair of injury. These individual milk components may have decreased the extent of freezing-induced death and cellular damage by stabilizing the
S. anatum
cell envelope.
Simplified Method for Purification of
Clostridium perfringens
Type A Enterotoxin
Authors: Sakaguchi Genji , Uemura Takashi , Riemann Hans P.
Published: December 2020

Purification of
Clostridium perfringens
type A enterotoxin from sporulated cells was simplified. The method consisted of precipitation of the enterotoxin from the extract of sonically treated cells at 40% saturation of ammonium sulfate at pH 7, differential solubilization in 0.02 M phosphate buffer, pH 6.7, and repeated gel filtration on Sephadex G-200. The purified enterotoxin was at least 98% pure in ultracentrifugation, polyacrylamide gel electrophoresis, and agar gel double diffusion. Recovery was over 74% from the sporulated cell extract. The toxin had biological activities of at least 4,700 mouse intravenous minimal lethal doses/mg of N, 3,900 capillary permeability-increasing U/mg of N in the guinea pig skin, and 210 rabbit intestinal loop distension U/mg of N. The toxin, containing no hexose, lipid, or nucleic acid, appeared to be identical in sedimentation constant, isoelectric point, and ultraviolet absorption spectrum to the toxin purified previously by different procedures.
Propionate Formation from Cellulose and Soluble Sugars by Combined Cultures of
Bacteroides succinogenes
and
Selenomonas ruminantium
Authors: Scheifinger C. C. , Wolin M. J.
Published: December 2020

Succinate is formed as an intermediate but not as a normal end product of the bovine rumen fermentation. However, numerous rumen bacteria are present, e.g.,
Bacteroides succinogenes
, which produce succinate as a major product of carbohydrate fermentation.
Selenomonas ruminantium
, another rumen species, produces propionate via the succinate or randomizing pathway. These two organisms were co-cultured to determine if
S. ruminantium
could decarboxylate succinate produced by
B. succinogenes
. When energy sources used competitively by both species, i.e. glucose or cellobiose, were employed, no succinate was found in combined cultures, although a significant amount was expected from the numbers of
Bacteroides
present. The propionate production per
S. ruminantium
was significantly greater in combined than in single
S. ruminantium
cultures, which indicated that
S. ruminantium
was decarboxylating the succinate produced by
B. succinogenes. S. ruminantium
, which does not use cellulose, grew on cellulose when co-cultured with
B. succinogenes
. Succinate, but not propionate, was produced from cellulose by
B. succinogenes
alone. Propionate, but no succinate, accumulated when the combined cultures were grown on cellulose. These interspecies interactions are models for the rumen ecosystem interactions involved in the production of succinate by one species and its decarboxylation to propionate by a second species.
Transient Response of Continuously Cultured Heterogeneous Populations to Changes in Temperature
Authors: George T. K. , Gaudy A. F.
Published: December 2020

Completely mixed, once-through continuous culture systems of heterogeneous microbial populations of sewage origin were systematically examined for response to changes in reactor temperature. Systems were operated at two dilution rates of 0.125 and 0.25 per h. “Steady state” conditions of the systems were assessed with the reactors operating at 25 C. From this base line, temperature was decreased to as low as 8 C and increased to as high as 57.5 C. Response was assessed in the ensuing transient phase as the system approached a new “steady state.” The response was measured by changes in amount and type of carbon source in the reactor effluent as determined by the chemical oxygen demand test, the anthrone test, and gas chromatography. Biological solids concentration and cell composition (protein, carbohydrate, ribonucleic acid and deoxyribonucleic acid) were also determined. These systems responded more favorably to increases than to decreases in temperature. Regardless of the direction of change, the system with the lowest dilution rate (D = 0.125 per h) responded more successfully; i.e., there was less leakage of carbon source in the effluent and less dilute-out of cells during the transient phase.
Changes in the Fungal Autoflora of Apollo Astronauts
Authors: Taylor Gerald R. , Henney Mary R. , Ellis Walter L.
Published: December 2020

Specimens were repeatedly obtained for mycological examination from the skin, throat, urine, and feces of the six astronauts who conducted the Apollo 14 and Apollo 15 lunar exploration missions. Analysis of preflight data demonstrates that the process of severely restricting opportunities from colonization for 3 weeks before flight resulted in a 50% reduction in the number of isolated species. Postflight data indicate that exposure to the space flight environment for up to 2 weeks resulted in an even greater reduction with a relative increase in the potential pathogen
Candida albicans
. No incidences of microbial shock were observed when crewmembers were quarantined for 16 days after completion of the space flight. Intercrew transfer of particular species could not be demonstrated because most species were not consistently recovered.
Method for Radiorespirometric Detection of Bacteria in Pure Culture and in Blood
Authors: Schrot J. Rudolph , Hess Walter C. , Levin Gilbert V.
Published: December 2020

Methods are described for the detection of low numbers of bacteria by monitoring
14
CO
2
evolved from
14
C-labeled substrates. Cell suspensions are filtered with membrane filters, and the filter is then moistened with 0.1 ml of labeled medium in a small, closed apparatus. Evolved
14
CO
2
is collected with Ba(OH)
2
-moistened filter pads and assayed with conventional radioactivity counting equipment. The kinetics of
14
CO
2
evolution are shown for several species of bacteria. Fewer than 100 colony-forming units of most species tested were detected in 2 h or less. Bacteria were inoculated into blood and the mixture was treated to lyse the blood cells. The suspension ws filtered and the filter was placed in a small volume of labeled medium. The evolved
14
CO
2
was trapped and counted. A key development in the methodology was finding that an aqueous solution of Rhyozyme and Triton X-100 produced lysis of blood but was not detrimental to bacteria.
Neutralization Studies with Marek's Disease Virus and Turkey Herpesvirus
Authors: Melchior F. W. , Fredrickson T. N. , Luginbuhl R. E.
Published: December 2020

Use of Marek's disease virus (MDV) in a neutralization test presents several problems, which are described, making this potentially useful test difficult. To obviate these difficulties, a plaque reduction test has been designed based on cross-neutralization of turkey herpesvirus (HVT) by serum-neutralizing MDV. The technique for such a neutralization test is outlined. Kinetics of development of neutralizing antibodies in chickens inoculated with HVT and MDV are described. The neutralization test can be used to evaluate viability of HVT vaccines and the possible role of neutralizing antibodies in the protection afforded by vaccination against MDV-induced tumors.
Isolation and Characterization of a Thermotolerant Methanol-Utilizing Yeast
Authors: Levine D. W. , Cooney C. L.
Published: December 2020

A yeast capable of growth on methanol as its sole carbon-energy source was isoalted from soil samples and identified as a strain of
Hansenula polymorpha
. A continuous enrichment culture at 37 C with a simple mineral salts medium was used to select this organism. The isolate, designated DL-1, has a maximal specific growth rate of 0.22 per h, at pH 4.5 to 5.5 and temperatures of 37 to 42 C, in simple mineral salts medium with methanol (0.5%), biotin, and thiamine. Growth occurred in a chemostat at temperatures up to 50 C, with strong growth at 45 C. The maximal growth yield of the yeast on methanol was 0.36 g of dry cell weight per g of methanol, and the yield on oxygen was 0.37 g of dry cell weight per g of O
2
. Protein content of the isolate is 46%, and total nucleic acid content varies from 5.0 to 7.0% with increasing growth rate from 0.08 to 0.20 per h. The amino acid profile of this yeast protein indicates that it could serve as a good source of food protein. Feeding studies with rats show the yeast to have no toxic effects.
Methods for Visualization of Enzymes in Polyacrylamide Gels
Authors: Payne W. J. , Fitzgerald J. W. , Dodgson K. S.
Published: December 2020

White bands resulting from precipitation of dodecan-1-ol liberated by hydrolysis of sodium dodecyl sulfate and decan-5-ol released by hydrolysis of decan-5-yl sulfate produced zymograms of the primary and secondary alkylsulfatases from
Pseudomonas
C
12
B. Gas-liquid chromatographic analyses of ether extracts of the precipitate-containing segments of the zymograms confirmed the identity of the alcohols which were not discerned in extracts of segments of the gels other than those containing precipitates. β-Galactosidase from
Escherichia coli
was marked on zymograms by the liberation of
o
-nitrophenol from
o
-nitrophenyl-β-D-galactoside, and arylsulfatase from
Pseudomonas
C
12
B was marked in gels by liberation of
p
-nitrophenol from
p
-nitrophenyl sulfate. Membrane-associated dissimilatory nitrate reductases from a nitrate respirer (
Enterobacter aerogenes
) and a denitrifier (
Pseudomonas perfectomarinus
) did not penetrate either 6.8 or 3% polyacrylamide gel but were demonstrable at the top of the gels. In the membrane-bound state, formate served as electron donor for nitrate reductase from
E. aerogenes
, and reduced nicotinamide adenine dinucleotide (NADH) served as donor for nitrate reductase from
P. perfectomarinus
. Both enzymes reduced nitrate at the expense of reduced benzyl viologen as well. Assimilatory nitrate reductase from
E. aerogenes
moved easily into the 6.8% gels (

R
f

= 0.43 under the conditions of these experiments). The reduced dye served as electron donor for the assimilatory reductase, but formate and NADH did not. Incubation of the membrane-associated nitrate reductases with 2% Triton X-100 solubilized the enzymes and removed the capacity of formate and NADH to serve as electron donors. Both retained the ability to reduce nitrate at the expense of reduced benzyl viologen. The solubilized dissimilatory reductase from
E. aerogenes
moved further in the gels (

R
f

= 0.49) than the soluble assimilatory reductase; the solubilized dissimilatory reductase from the denitrifier,
P. perfectomarinus
, moved further in the gels (

R
f

= 0.64) than either of the enzymes from
E. aerogenes
.
Simple Genetic Transformation Assay for Rapid Diagnosis of
Moraxella osloensis
Authors: Juni Elliot
Published: December 2020

A genetic transformation assay for unequivocal identification of strains of
Moraxella osloensis
is described. In this assay a stable tryptophan auxotroph is transformed to prototrophy by deoxyribonucleic acid (DNA) samples from other strains of
M. osloensis
but not by DNA samples from unrelated bacteria. The test is simple to perform and definitive results can be obtained in less than 24 h. The procedure, which is suitable for routine diagnosis in a clinical laboratory, involves a rapid method for preparation of crude transforming DNA from small quantities of bacterial cells and permits simultaneous examination of large numbers of isolated cultures. The assay was shown to correctly identify 27 strains previously classified as
M. osloensis
. Forty-five other gram-negative, oxidase-positive, nonmotile coccobacilli, which might be confused with
M. osloensis
unless subject to more extensive testing, were shown to be unrelated genetically to
M. osloensis
. The transformation assay clearly distinguishes
M. osloensis
from
Acinetobacter
. Although most strains of
M. osloensis
are nonfastidious, being able to grow in a mineral medium supplemented with a single organic carbon source, one of the strains tested was only able to grow on fairly complex media and could not be transformed to grow on simple media. Inability to alkalize Simmons citrate agar was shown not to be characteristic of all strains of
M. osloensis
.
Clinical Evaluation of Enteric Media in the Primary Isolation of Salmonella and Shigella
Authors: Pollock Helen M. , Dahlgren Bonnie J.
Published: December 2020

Over a 1-year period, media for the isolation of enteric pathogens were compared on 455 stool specimens. Fifty-three pathogens were isolated, of which 56% were
Shigella sonnei
and 13% were
Sh. flexneri
. Of these isolates, 90% were found on xylose-lysine-desoxycholate agar, 87% on Hekton enteric agar, and 80% on MacConkey without crystal violet with 2% agar and 0.007% neutral red, but only 28% were recovered on
Salmonella-Shigella
agar. Less than one-half of the shigellae were recovered after Selenite-F enrichment. On the other hand, enrichment was the most helpful method for isolating salmonellae. Studies on cultures from which mixed isolates were obtained indicated that numbers and chance distribution have an effect on the results obtained. The performance of
Salmonella-Shigella
agar in the isolation of enteric pathogens was inferior, and the effort involved to obtain those isolates was greater than for Hekton enteric and xylose-lysine-desoxycholate agars.
Use of Japanese Quail Embryo Fibroblast Cells for Propagation and Assay of Turkey Herpesvirus FC-126
Authors: Colwell W. M. , Simmons D. G. , Muse K. E.
Published: December 2020

Japanese quail (
Coturnix coturnix japonica
) fibroblast cell culture monolayers were found to provide a very satisfactory system in which to propagate and assay turkey herpesvirus FC-126, which is used for production of Marek's disease vaccine. Japanese quail cells were more sensitive than duck cells and of approximately equal sensitivity to chicken cells. Foci of infection developed rapidly and uniformly, were of larger size, and were more easily discernible in quail cells than in chicken cells.
Microagglutination Test for Detecting and Measuring Serum Agglutinins of
Francisella tularensis
Authors: Massey Eugene D. , Mangiafico Joseph A.
Published: December 2020

A microagglutination method utilizing stained antigen for detecting and measuring serum agglutinins against
Francisella tularensis
is described. The microagglutination and standard tube agglutination techniques were demonstrated to be comparable in sensitivity and specificity. Advantages of the micro method are rapidity and ease of performance, economy of reagents and, in particular, ease of interpreting specific reactivity.
Improved KCN Medium
Authors: Munson Terry E.
Published: December 2020

A semisolid tetrazolium salt agar medium developed for testing sensitivity to KCN is easier to interpret, has a longer storage life, and is less critical in the size of inoculum than is Moeller KCN broth medium.
Immunoperoxidase Staining of Leptospires
Authors: Tripathy D. N. , Hanson L. E.
Published: December 2020

Leptospires were detectable by light microscopy when Formalin-fixed preparations were reacted by direct and indirect methods with horseradish peroxidase-labeled specific antibody.
Limitations of the Use of 5-Fluorouracil as a Selective Agent for the Isolation of Leptospirae
Authors: Ris D. R.
Published: December 2020

It has been shown that some component of Fletcher medium is able to annul the inhibitory action of 5-fluorouracil (400 μg/ml) on bacteria other than leptospirae. The most likely ingredient which can be implicated in this context appears to be beef extract.
Pyocin Sensitivity of
Pseudomonas
Species
Authors: Jones Lois F. , Thomas E. T. , Stinnett J. D. , Gilardi Gerald L. , Farmer J. J.
Published: December 2020

Only the fluorescent pseudomonads,
Pseudomonas aeruginosa, P. putida
, and
P. fluorescens
, were sensitive to pyocins produced from
P. aeruginosa
.
Method for Performing Aerobic Plate Counts of Anhydrous Cosmetics Utilizing Tween 60 and Arlacel 80 as Dispersing Agents
Authors: McConville John F. , Anger Claude B. , Anderson David W.
Published: December 2020

An aqueous diluent containing Tween 60 and Arlacel 80 gave greater recovery of microorganisms when compared with two common diluents as determined by aerobic plate count of inoculated anhydrous cosmetics. The greater recovery was caused by better dispersion of the anhydrous cosmetics in the diluents.
Evaluation of Type A Botulinal Toxin Assays that Use Antitoxin to Crystalline Toxin
Authors: Sugiyama H. , Ohishi I. , Dasgupta B. R.
Published: December 2020

The type A botulinal toxin assay by the reverse passive hemagglutination procedure which uses antitoxin to crystalline toxin was examined for specificity. The analysis was based on the fact that crystalline type A toxin is a complex of neurotoxic protein (Aα) and a nontoxic protein (Aβ). By using these components, obtained in essentially pure forms, it was shown that the antitoxin to crystalline toxin has a significantly higher titer to Aβ than to Aα. When Formalin-treated red blood cells were sensitized with this antitoxin, the antibodies coupled to the cells were, for practical results, only anti-Aβ. When the suspension is reacted with dilutions of type A toxic solutions, the limiting dilutions are determined by Aβ and not by the neurotoxin, which should be the determinant if the assay is to measure toxicity. These observations may be pertinent to the development of serological assays for other botulinal toxin types.
Stable Mycoplasma Antigen Preparations for Indirect Hemagglutination Tests
Authors: Lam Gow T. , Morton Harry E.
Published: December 2020

In immunological studies of mycoplasmas, the use of glutaraldehyde for the fixative makes it possible to use erythrocytes from commercially available defibrinated sheep blood. It eliminates the necessity of having to screen blood from individual sheep to obtain a suitable source of erythrocytes, as when employing tannic acid for fixation and sensitization. The chemical bonding of soluble mycoplasma proteins to glutaraladehyde-fixed sheep erythrocytes by bis-diazotized 3,3′dimethoxy derivative, benzidine, yields preparations that are satisfactory antigens for performing the indirect hemagglutination test by the microtiter technique. The antigenic preparations are satisfactory for use after storage at 4 or -10 C for many months. Incorporation of 5% glycerine in the final suspending milieu makes it possible to obtain uniform suspensions of the fixed and sensitized sheep erythrocytes after freezing and after repeated freezing and thawing. Proteins from
Mycoplasma arthritidis
and
M. hominis
have been coupled to glutaraldehyde-fixed erythrocytes by diazotization. The last mentioned preparation detected the presence of antibodies in titers greater than 1:10 in 37% of 237 pregnant women whose ages ranged between 20 and 30 years. There was no correlation between the presence of specific antibodies in the blood and the isolation of
M. hominis
from the cervical canal.
Slide Agglutination Method for the Serological Identification of
Neisseria gonorrhoeae
with Anti-Gonococcal Antibodies Adsorbed to Protein A-Containing Staphylococci
Authors: Danielsson Dan , Kronvall Göran
Published: December 2020

A rapid slide agglutination test has been developed for the identification of
Neisseria gonorrhoeae
that are primarily detected as oxidase-positive colonies in gonococcal cultures. The technique is based on the specific nonimmune reactivity between the Fc portion of immunoglobulin (Ig)G and staphylococcal protein A. IgG molecules adsorbed to stabilized staphylococci will thereby become oriented with their antigen-reactive sites that are directed outwards. Protein A-containing staphylococci with unabsorbed anti-gonococcal antibodies gave positive co-agglutination reactions with gonococci but also with meningococci, some
Moraxella, Haemophilus
, and
Pseudomonas
strains. These crossreactions were eliminated by absorption of the anti-gonococcal antiserum with meningococcal and
Moraxella
organisms prior to the coating of reagent staphylococci. In the routine culture diagnosis of
N. gonorrhoeae
the use of specific gonococcal reagent staphylococci gave concordant results with fermentation procedures and immunofluorescent techniques.
Production of Glutaric Acid: a Useful Criterion for Differentiating
Pseudomonas diminuta
from
Pseudomonas vesiculare
Authors: Moss C. Wayne , Kaltenbach C. M.
Published: December 2020

A gas-liquid chromatographic procedure was used to determine short-chain acids produced by
Pseudomonas diminuta
and
P. vesiculare
after growth on Trypticase soy agar. Each of nine strains of
P. diminuta
produced glutaric acid, whereas none of the strains of
P. vesiculare
produced this acid.
New Method for Study of Peptide Transport in Bacteria
Authors: Cascieri T. , Mallette M. F.
Published: December 2020

The transport system for glycylmethionine in
Escherichia coli
B and
Salmonella typhimurium
LT2 was examined by a new approach which may be applied to other types of exogenous materials. Physiological auxotrophs were prepared by growing wild strains in a methionine-containing medium to repress the methionine biosynthetic enzymes. Immediate protein synthesis was shown to take place in such physiological auxotrophs only in the presence of either exogenous methionine or a methionine peptide, e.g., glycylmethionine. Protein synthesis was dependent on glycylmethionine taken up by the cell and was indicated by assaying for the inducible enzyme lysine decarboxylase at 5- to 15-min intervals. Uptake was studied by using low concentrations of glycylmethionine, therefore making uptake by permease the limiting step in incorporation of methionine into protein, and by addition of competitor peptides to media containing saturating concentrations of glycylmethionine. Lysine decarboxylase activity in
S. typhimurium
LT2 was about 80 times that present in
E. coli
B. Glycylmethionine transport had a
K
m
of the order of 1 μM in
S. typhimurium
. Structural specificities observed for peptide transport by other workers were confirmed for
E. coli
B. Competitive inhibition of glycylmethionine uptake by dipeptides was observed in
E. coli
.
Effect of Lysozyme on the Recovery of Heated
Clostridium botulinum
Spores
Authors: Alderton Gordon , Chen John K. , Ito Keith A.
Published: December 2020

Lysozyme in the recovery medium increased the recovery of heated spores, thereby raising the measured heat resistance of type E
Clostridium botulinum
spores about 1,800-fold and type A spores up to 3-fold.
Survival Studies with Spores of
Clostridium botulinum
Type E in Pasteurized Meat of the Blue Crab
Callinectes sapidus
Authors: Cockey Ralph R. , Tatro Mahlon C.
Published: December 2020

Clostridium botulinum
type E studies reported in this paper include the incidence of the organism in selected Chesapeake Bay areas, growth and toxin production in crabmeat homogenates, and the effect of pasteurization upon varying levels of spores in crabmeat. Type E spores were detected in 21 of 24 bottom mud samples taken at locations from which blue crabs were being harvested. Sterilized crabmeat homogenates inoculated with as little as five spores per 10 g became toxic after 8 days at 50 F, 2 days at 75 F, and 1 day at 85 F. Growth at 50 F and above was accompanied by gas production and a slightly sour odor. Growth and toxin production at 40 F required 55 days or longer and inocula of 10
3
spores or higher per 10 g of homogenate. At 40 F gas production was usually not apparent and no off odors could be detected. A recommended minimum pasteurization of 1 min at 185 F internal meat temperature reduced type E spore levels in inoculated packs of crabmeat from 10
8
spores per 100 g to 6 or less spores per 100 g, and the pasteurized meat remained nontoxic during 6 months of storage at 40 F.
Some Factors Affecting the Viability of Dried Bacteria During Storage In Vacuo
Authors: Marshall Betty J. , Coote G. G. , Scott W. J.
Published: December 2020

The effects of various substances on the viability of freeze-dried cells of
Pseudomonas fluorescens
and
Salmonella newport
were studied during storage in vacuo for 5 years. Mixtures of two organisms were dried together and studied in two factorial experiments. The first was a complete factorial using six factors and two levels; the second was a fractional replicate with four factors at two levels and three others at four concentrations. A study of ribose binding by cells of
S. newport
was made by using [U-
14
C]ribose. Substantial improvements in viability were obtained by drying in the presence of sucrose, glutamate, and semicarbazide. Low concentrations of ribose increased the death rate during drying, but these adverse effects were prevented by equimolar amounts of semicarbazide. Ribose binding increased with storage time and, although its incorporation changed, most of the increase in total ribose occurred after the main decrease in viability. Storage temperature caused larger changes in viability than did level changes of residual water in the cells. Although the results are complicated by a large number of interactions, they confirm and extend the hypothesis that reactions between carbonyl compounds and cellular components are a major cause of the mortality occurring during storage of dried microorganisms. A particular mixture of sucrose, glutamate, and semicarbazide is proposed as a means of reducing death when prolonged storage in the dry state is desired.
Trypsinized Human Group O Erythrocytes as an Alternative Hemagglutinating Agent for Japanese Encephalitis Virus
Authors: Shortridge K. F. , Hu L. Y.
Published: December 2020

Trypsinized human group O erythrocytes were found to be a suitable alternative to gander cells in hemagglutination (HA) and hemagglutination inhibition (HAI) tests for Japanese encephalitis (JE) virus. In the HAI test, no cross-reactions against JE virus were observed with immune sera containing antibody to taxonomically related or unrelated viruses, with mouse brain antigen, or with nonantibody serum inhibitors; specific antibody rise could be detected in an immunized rabbit. Gander and trypsinized human group O cells gave comparable titers in the HAI test, but the latter were preferable since (i) they required less challenging HA antigen, being more sensitive to agglutination by JE virus, and (ii) all human and some animal sera investigated were devoid of natural agglutinins for these cells, thereby eliminating or reducing the need for prior adsorption with packed cells.
Hydrogen Sulfide Production by
Pseudomonas putrefaciens
in Shrimp Experimentally Packed in Nitrogen
Authors: Lapin R. M. , Koburger J. A.
Published: December 2020

Shrimp refrigerated in a nitrogen atmosphere develop off-odors not typical of normal spoilage. Investigations of this phenomenon showed that hydrogen sulfide developed in the headspace gas, and a large percentage of the microbial population present on the shrimp stored in nitrogen was capable of hydrogen sulfide production, in contrast to the flora on shrimp stored in air. The predominant hydrogen sulfide-producing organism,
Pseudomonas putrefaciens
, was present in low numbers on fresh shrimp but usually reached high numbers by day 8 of nitrogen storage. Further studies revealed that cysteine and cystine were the probable substrates in shrimp utilized by this organism for hydrogen sulfide production. When shrimp sterilized by irradiation were inoculated with
P. putrefaciens
and incubated in an atmosphere of nitrogen, hydrogen sulfide and the characteristic off-odors developed.
Isolation of
Edwardsiella tarda
from Swine
Authors: Owens Dwight R. , Nelson Stuart L. , Addison J. Bruce
Published: December 2020

Edwardsiella tarda
was isolated from the intestinal tract of a 2-month-old pig. This is the first reported isolation of
Edwardsiella tarda
from swine in the United States. Swine have been reported as potential carriers of
Edwardsiella tarda
, but pathogenicity of this organism for swine has not been determined. Although the pig had access to several farm ponds, the exact source of infection was not determined.
Phosphatase Activity of Anaerobic Organisms
Authors: Porschen Richard K. , Spaulding Earle H.
Published: December 2020

Anaerobic organisms were tested for phosphatase activity in different pH ranges. Several groups of organisms displayed characteristic patterns.
Bacteroides fragilis, B. melaninogenicus
, and
B. ruminicola
produced phosphatase with strongest activity at pH 8.6.
Fusobacterium mortiferum
was the only species of this genus to show strong hydrolysis. The enzyme was active in both acid and alkaline ranges. The activity of gram-positive organisms was variable, the most active groups being
Clostridium perfringens, Peptostreptococcus intermedius, P. micros
, and
Peptococcus constellatus
. The incorporation of phosphatase activity into the identification scheme of anaerobes seems feasible. There was a correlation of hydrolysis with several important pathogens.
Production of Multivalent Fluorescent Antisera for Identification of Organisms in the
Mycobacterium avium-Mycobacterium intracellulare
Complex
Authors: Gales Peter W. , Martins Ronald R. , Walker William E.
Published: December 2020

Antisera to ten strains of mycobacteria in the
Mycobacterium avium-Mycobacterium intracellulare
group were obtained by injecting rabbits with ultraviolet light-killed cells. The antisera were conjugated with fluorescein isothiocyanate and used in the direct fluorescent antibody test. Individual antisera reacted specifically with the mycobacterial serotype used to produce them. The antisera were then combined in two multivalent pools. Each multivalent pool reacted specifically with its corresponding antigens. The multivalent antisera were thus found to provide a rapid identification method for the mycobacteria studied.
Microbiology Study of a Hypersaline Lake in French Somaliland
Authors: Brisou J. , Courtois D. , Denis F.
Published: December 2020

In a study of a lake having a higher concentration of salts than the Dead Sea, all of the heterotrophic bacteria isolated were aerobes; no strictly anaerobic strains were found. Ninety percent of the strains were euryhalines and ten percent were strict halophiles. The extreme halophiles belonged to the species
Halobacterium trapanicum
and
Halococcus morrhuae
.
Environmental Factors Influencing Isolation of Enteroviruses from Polluted Surface Waters
Authors: Metcalf Theodore G. , Wallis Craig , Melnick Joseph L.
Published: December 2020

The influence of water quality upon the concentration of virus on location was assessed in field studies conducted in the Houston ship channel, Galveston Bay, and Houston waste treatment plants. Clarification of polluted surface waters was accomplished with minimal loss of virus. Virus from clarified sewage effluents and saline waters was then adsorbed and concentrated on textile and membrane filter surfaces. Direct measurements of virus from large volumes of polluted surface waters under existing field conditions were then made using the virus concentrator equipment.