bluuebunny/crossref_metadata_2025 huggingface dataset:
Bacteremia After Tooth Extractions Studied with the Aid of Prereduced Anaerobically Sterilized Culture Media
Authors: Crawford James J. , Sconyers J. R. , Moriarty John D. , King Ronald C. , West Jeffrey F.
Published: December 2020

Both prereduced molten agar and broth and aerobic molten agar and broth were inoculated with blood samples collected from patients with periodontitis, but in otherwise good health, both before and after extraction of two or more teeth. Postoperative blood samples from 23 of 25 patients sampled yielded anaerobic and facultative species. Colony counts from nine samples yielded from less than 1 to over 100 colonies per ml of blood. Organisms detected were species belonging to the genera
Bacteroides, Fusobacterium, Peptostreptococcus, Leptotrichia, Propionibacterium, Peptococcus, Veillonella
, plus
Streptococcus mitis, S. salivarius
, vibrio forms, and strains resembling
S. mutans
. The data indicate that prereduced anaerobically sterilized culture medium with polyanethol sulfonate is effective for detecting anaerobic species in bacteremia and that anaerobic species can be prevalent in bacteremias immediately after tooth extraction in patients with periodontitis.
Concentration of Oncogenic Herpesviruses by Methyl Alcohol Precipitation
Authors: Goodheart C. R. , Armstrong G. R. , Ablashi D. V. , Pearson G. , Orr T. W.
Published: December 2020

Oncogenic herpesviruses, like many other viruses, can be concentrated effectively from large volumes of culture fluids by precipitation with methanol with good recovery of infectivity.
Microbial Petroleum Degradation: Use of Mixed Hydrocarbon Substrates
Authors: Walker J. D. , Colwell R. R.
Published: December 2020

Methods of examining hydrocarbons to estimate the microbial degradation of petroleum are compared. Gas-liquid chromatography with a mixed hydrocarbon substrate has been shown to be useful in evaluating microbial potential for degradation of a number of hydrocarbons.
Sodium Polyanethol Sulfonate Sensitivity of Anaerobic Cocci
Authors: Graves Michael H. , Morello Josephine A. , Kocka Frank E.
Published: December 2020

Growth of
Peptostreptococcus anaerobius
was shown to be totally inhibited by sodium polyanethol sulfonate (SPS). Other anaerobic cocci grew in the presence of SPS although some strains of
Peptococcus prevotii
and
Peptococcus magnus
showed delayed growth. A SPS disk assay for the presumptive identification of
P. anaerobius
is described.
Culture Purity Assessments and Morphological Dissociation in the Pleomorphic Microorganism
Bacterionema matruchotii
Authors: Gilmour Marion N. , Turner Gwendolyn
Published: December 2020

The inherent pleomorphism of
Bacterionema matruchotii
resulting from its mode of reproduction was enhanced by temporal effects of culture age and growth condition and by the more lasting effects of rough to intermediate to smooth morphological dissociation. Routine morphological observations with a single growth condition were inadequate to permit unambiguous judgements of culture purity. Multiple criteria were required. Pleomorphism and the undetected presence of contaminants in primary and successive cultures of
B. matruchotii
can explain the emergence of unrelated bacteria from
B. matruchotii
reported previously by others and ascribed to genetic instability.
Ultrastructure of a Thermotolerant Basidiomycete Possibly Suitable for Production of Food Protein
Authors: Hofsten Bengt V. , Hofsten Angelica V.
Published: December 2020

The imperfect cellulolytic fungus
Sporotrichum pulverulentum
, which is commonly found growing in wood-chip piles, was grown in submerged culture on wheat shorts and other cereal flours. These substrates were broken down in 1 to 4 days at 30 to 40 C, and the mycelial mass was easily harvested by filtration. Scanning electron micrographs of hyphae in mycelial pellets are presented, and thin sections of conidia and hyphae were studied in a transmission electron microscope. Dolipores in septa of hyphae were observed, and cell walls are shown to be lamellar, which is characteristic of the
Basidiomycetes
. Actively growing hyphae are full of cytoplasm with numerous mitochondria, whereas old mycelial pellets contain highly vacuolated and almost empty cells.
Characterization of the Precipitin Bands Detected in the Immunodiffusion Test for Paracoccidioidomycosis
Authors: Restrepo Angela , Moncada Luz H.
Published: December 2020

In order to characterize the precipitin bands detected in the immunodiffusion test for paracoccidioidomycosis, a study was undertaken in 54 patients with the disease. On the basis of the pattern of known control sera, the three commonly observed lines of precipitate were designated as 1, 2, and 3 according to their location in the immunodiffusion plate. At time of diagnosis, 28 of the patients exhibited all three bands, 16 gave two bands, and 10 showed only one precipitin line. Over 50 of the sera with three bands had high complement fixation titers (above 1:512), whereas those with one band exhibited lower titers. A similar picture was obtained with the quantitative agar-gel techniques, where titers of 1:64 and above were more commonly observed in sera with three precipitin lines. Follow-up studies carried out in 18 patients revealed that band 3 disappeared first, followed by band 2, and, finally, by band 1. At the end of 2 to 3 years, 85.7% of the patients had lost band 3, 75% band 2, and only 27.7% band 1. Cross-reactions with histoplasmin were found in eight patients who gave the M precipitin line with this antigen. It was found that the latter band and our paracoccidioidin band 3 fused, producing lines of identity. Bands 1 and 2 were specific. The implications of these findings are discussed.
Biochemical and Antibiotic Susceptibility Studies of H
2
S-Negative
Citrobacter
Authors: Lund Marlys E. , Matsen John M. , Blazevic Donna J.
Published: December 2020

Ninety-four strains of H
2
S-negative
Citrobacter
were biochemically characterized and their antibiograms were determined. The antibiograms demonstrated not only a difference from
Enterobacter cloacae
but also a difference within the
Citrobacter
group between the indole-negative and indole-positive strains. These differences were statistically significant and emphasize the importance of the indole reaction as an aid to speciation of the H
2
S-negative
Citrobacter
.
Evaluation of Miniature Test for Bacteriuria Using Dehydrated Media and Nitrite Pads
Authors: Moffat Craig M. , Britt Michael R. , Burke John P.
Published: December 2020

A new dip-inoculum method for detecting bacteriuria which utilizes dehydrated media pads and a nitrite pad attached to a small plastic strip was evaluated in hospitalized patients. Discrepant interpretations were made by independent observers in 9.3% of the specimens with > 10
5
colonies per ml. The media pads failed to support growth of yeast and gave variable results with
Staphylococcus epidermidis
and non-group D streptococci. False-negative culture results commonly occurred if the patients were receiving antibiotics. The nitrite test occasionally remained positive for brief periods after the elimination of bacteriuria by antibiotics. Conditions and drugs (especially phenazopyridine) which discolor urine interfered with reading both the culture and nitrite tests. Although not suitable for hospital use, or for monitoring therapy, the test strip is probably as reliable as the calibrated loop-streak plate culture for office screening.
Inhibition of Brewer's Yeasts by Wheat Purothionins
Authors: Hernandez-Lucas C. , De Caleya R. Fernandez , Carbonero Pilar
Published: December 2020

Purothionins are basic polypeptides with antimicrobial properties that are present in the endosperm of wheat and other
Gramineae
. Susceptibility to crude and electrophoretically purified purothionins among brewing starters has been investigated. Seven yeast strains of
Saccharomyces uvarum
(syn.
carlsbergensis
), four strains of
Saccharomyces cerevisiae
, and four wild strains (
Saccharomyces
spp.) have been tested in three culture media. All the strains were susceptible to the crude preparation in a yeast extract-glucose medium. Determinations of minimal inhibitory and biocidal concentrations yielded double end points in about half of the assays. The highest sensitivity to purothionins was obtained in malt extract medium. Sensitivity to electrophoretically purified purothionins was of the same order or smaller than to the crude preparation. Possible explanations for this unexpected result are presented.
Liquid Scintillation Vial for Cumulative and Continuous Radiometric Measurement of In Vitro Metabolism
Authors: Buddemeyer Edward U.
Published: December 2020

A two-compartment vial is described in which suspensions of bacteria, cells, or tissues may be cultured and their growth and metabolism measured radiometrically by using a liquid scintillation counter. The device consists of a scintillation vial lined with a cylinder of scintillating paper into which is placed a sterilized inner culture vial containing a carbon-14 substrate. The assembled device can be carried by the sample transport systems of conventional liquid scintillation counters. Evolved
14
CO
2
is collected and measured cumulatively and continuously. The device can be constructed simply and economically from readily available reagents and glassware. Data are given on relative sensitivity and on the effect of the color and transparency of the inner vial. A pilot experiment with bacteria (
Escherichia coli
) is described.
Quantitative Infrared Photoanalysis of Selected Bacteria
Authors: Dugan D. L. , Wright D. N.
Published: December 2020

A technique to measure transmitted infrared radiation from minute biological systems is described. Infrared color film was exposed by radiation transmitted through bacterial colonies. The resultant photographic image was unique for each species of bacteria examined and spectral analysis of the image provided differential light emission patterns which could be quantitated. A formula for developing numerical comparisons among bacterial colonies was provided. The results of this numerical procedure gave quantitative relationships for the total infrared data from each microbial colony and made possible the differential identification of ten species of medically significant bacteria.
Evaluation of Four Blood Culture Systems Using Parallel Culture Methods
Authors: Rosner Richard
Published: December 2020

Commercially prepared Vacutainer thioglycolate broth with SPS (TBSPS), the B-D Vacutainer culture tube with SPS (VCT), the Pfizer E-Vac hypertonic brucella broth with SPS (BBSPS), and our own Trypticase-soy hypertonic broth with SPS (TSBH) were studied by parallel culture methods for their ability to allow the survival of a wide spectrum of organisms, their ability to allow recovery of organisms, and the time required to obtain a recovery from clinical blood cultures. Organisms considered to be clinically significant were recovered from 176 blood cultures. The TSBH system produced all 176 recoveries, the BBSPS system allowed for 170 recoveries, the TBSPS recovered 131, and the VCT accounted for 106 recoveries. The time required to recover any given organism from both the BBSPS and the TSBH systems did not exceed 48 h, whereas 86 of the 131 recoveries from the TBSPS system required more than 72 h and 74 of the 106 VCT recoveries also required more than 72 h. A wide spectrum of organisms were recovered from both the BBSPS and the TSBH systems. The TBSPS system failed to allow the recovery of many streptococci and
Pseudomonas
spp. and the VCT system failed to recover many organisms.
Nutritional Features of
Bacteroides fragilis
subsp.
fragilis
Authors: Varel Vincent H. , Bryant Marvin P.
Published: December 2020

Studies of three reference strains of
Bacteroides fragilis
subsp.
fragilis
showed that they grow well in a minimal defined medium containing glucose, hemin, vitamin B
12
, minerals, bicarbonate-carbon dioxide buffer, NH
4
Cl, and sulfide. The vitamin B
12
requirement of 0.1 ng/ml was replaced with 7.5 μg of methionine. Cysteine or sulfide was an excellent source of sulfur, thioglycolate was a poor source, and thiosulfate, methionine, β-mercaptoethanol, dithiothreitol, sulfate, or sulfite did not serve as sole sources of sulfur. Neither single amino acids, nitrate, urea, nor a complex mixture of L-amino acids or peptides effectively replaced ammonia as the nitrogen source. Comparative studies with a few strains of other subspecies of
B. fragilis
including
B. fragilis
subsp.
vulgatus, B. fragilis
subsp.
thetaiotaomicron
, and
B. fragilis
subsp.
distasonis
indicate that they exhibit similar growth responses in the minimal medium. A single strain of
B. fragilis
subsp.
ovatus
required other materials. The results indicate the great biosynthetic ability of these organisms and suggest that, in their ecological niche within the large intestine, many nutrients such as amino acids are in very low supply, whereas materials such as ammonia, heme, and vitamin B
12
, or related compounds, must be available during much of the time.
Bacteriological Assessment of Spoon River Water Quality
Authors: Lin Shundar , Evans Ralph L. , Beuscher Davis B.
Published: December 2020

Data from a study of five stations on the Spoon River, Ill., during June 1971 through May 1973 were analyzed for compliance with Illinois Pollution Control Board's water quality standards of a geometric mean limitation of 200 fecal coliforms per 100 ml. This bacterial limit was achieved about 20% of the time during June 1971 through May 1972, and was never achieved during June 1972 through May 1973. Ratios of fecal coliform to total coliform are presented. By using fecal coliform-to-fecal streptococcus ratios to sort out fecal pollution origins, it was evident that a concern must be expressed not only for municipal wastewater effluents to the receiving stream, but also for nonpoint sources of pollution in assessing the bacterial quality of a stream.
Mouse Interferon in Ascitic Fluids
Authors: Buckley Sonja M. , Casals Jordi
Published: December 2020

Mouse interferon was obtained in relatively large volumes by the use of ascitic fluid from mice bearing sarcoma 180/TG and subsequently inoculated with Germiston virus.
Rice-Grown
Rhizopus oligosporus
Inoculum for Tempeh Fermentation
Authors: Rusmin Simon , Ko Swan Djien
Published: December 2020

A method of growing
Rhizopus oligosporus
on cooked rice as the inoculum for the fermentation of soybeans into tempeh was described and evaluated. Isolated
R. oligosporus
spores on glass beads survived best at low temperature and intermediate humidity. The activity of the rice-grown inoculum to ferment soybeans into tempeh did not decrease appreciably when stored desiccated for one year at 4 C or room temperature. Bacterial contaminants as high as 10
8
counts per g of cooked soybeans did not seem to affect the fermentation.
Stability of Minute Virus of Mice to Chemical and Physical Agents
Authors: Harris Robert E. , Coleman Philip H. , Morahan Page S.
Published: December 2020

Minute virus of mice (MVM), a single-stranded deoxyribonucleic acid Parvovirus, was subjected to various inactivation procedures, including chemical disinfectants, heat, and ultraviolet radiation. MVM was found to be less stable than has been reported for other Parvoviruses. This virus was readily inactivated by a variety of chemical disinfectants, including alcohols, formaldehyde, glutaraldehyde, and chloroform. MVM was more sensitive to ultraviolet radiation than was Kilham's rat virus. MVM was more sensitive to heating at temperatures of 35 to 100 C than has been reported for other Parvoviruses. More than 95% of MVM infectivity was inactivated by heating (45, 60, or 100 C) for 60 min, acid (pH 2.0) treatment, or ultraviolet radiation treatment, although a small percentage (less than 2%) of the virus preparation was found to be resistant to these treatments. In addition, more than 99% of the infectivity of MVM was lost after storage at 4C for 10 weeks, although the virus was stable on storage in liquid nitrogen.
Sewage Treatment by Controlled Eutrophication: Bacterial Study
Authors: Songer J. Glenn , Smith Rodney F. , Trieff N. M.
Published: December 2020

Several groups of bacteria were isolated and identified in an evaluation of the microbiological properties of a sewage treatment system involving the process of controlled eutrophication in a marine setting (J. G. Songer, N. M. Trieff, R. F. Smith, and D. Grajcer, 1974). Fecal coliforms, enterococci,
Salmonellae, Shigellae, Vibrio parahaemolyticus
, and
Vibrio alginolyticus
were studied at three stages of the treatment process. Significant reductions in fecal coliforms (
P
< 0.01) and enterococci (
P
< 0.01) were noted from raw sewage to effluent.
Salmonellae
and
Shigellae
were not detected at any stage, nor was
V. parahaemolyticus. V. alginolyticus
was isolated from the effluent only, reflecting the halophilic nature of the organism; low concentrations in raw sewage increased in the more saline effluent. Brine shrimp (
Artemia salina
), the herbivores in this system, were tested and found to have extremely low numbers of the organisms under study associated with them. Findings point further toward the use of this system as a combined mariculture-sewage treatment facility.
Malformin in
Aspergillus niger
-Infected Onion Bulbs (
Allium cepa
)
Authors: Curtis Roy W. , Stevenson Walter R. , Tuite John
Published: December 2020

Malformin was identified, by its biological activity and chromatography, in acetone extracts of the outer scales of onion bulbs infected with
Aspergillus niger
. Malformin was not detected in tissue underlying the infected areas or in the central portions of the bulbs, nor was malformein liberated from extracts or extracted tissues after reduction with zinc in acetic acid. This is the first report of naturally occurring malformin.

Images
Radiometric Measurement of Metabolic Activity of
Mycobacterium lepraemurium
Authors: Camargo Edwaldo E. , Larson Steven M. , Tepper Byron S. , Wagner Henry N.
Published: December 2020

A sensitive and nondestructive radiometric method has been applied to the detection of metabolism of
Mycobacterium lepraemurium
, as a model for the study of the metabolism and substrate requirements of
M. leprae
. The method is based on the measurement of the
14
CO
2
produced through the bacterial conversion of [U-
14
C]acetate or [U-
14
C]glycerol by 7 � 10
9
bacteria suspended in 10 ml of either a simple buffer system (K-36) or a complex medium (NC-5). Metabolism of the bacilli was easily detected within 3 days after inoculation and was measured daily. NC-5 medium supported metabolism of
M. lepraemurium
for several weeks longer than the simple K-36 buffer. The radiometric technique shows promise as a rapid and efficient system for evaluating the metabolism of mycobacteria without introducing any changes in the physiologic state of the organisms, studying their metabolic pathways, determining conditions potentially favorable for multiplication of these organisms in vitro, and studying their susceptibility to inhibition by drugs.
Gas-Tight Flask for the Concurrent Measurement of Gas Metabolism and Growth in Methane-Oxidizing Bacteria
Authors: Munoz Elaine F. , Silverman Melvin P.
Published: December 2020

A flask is described for use in conjunction with a gas chromatograph and a spectrophotometer to follow methane and oxygen uptake, carbon dioxide production, and cell growth concurrently in methane-oxidizing cultures.
Combined Biochemical and Serological Typing of Clinical Isolates of
Klebsiella
Authors: Rennie R. P. , Duncan I. B. R.
Published: December 2020

In a series of 640 strains of
Klebsiella
isolated from clinical specimens over a 7-month period, there were sufficient biochemical differences between strains to allow a biochemical typing system to be established. Biochemical tests were done in solid media inoculated with a modified Steers inocula replicator. Biotypes were designated by a numerical coding system; 29 distinct biotypes were found among the 640 strains of
Klebsiella
. Serotyping of 270 of the strains was done by the Quellung reaction, and 40 capsular types were identified. Numerical biotypes and serotypes of strains appeared to vary independently. When used in conjunction, the two methods subdivided the strains into many more distinct types than either used alone. With the combined method over 100 types of
Klebsiella
were distinguished among the 270 isolates.
Microadaption of Hemadsorption Inhibition for Neutralization Tests with Pig Hemagglutinating Encephalomyelitis Virus
Authors: Sørensen K. J.
Published: December 2020

A microneutralization test is described, in which secondary pig thyroid cells are used and end points are determined by hemadsorption with hamster erythrocytes. The method is evaluated and compared with a macromethod, in which the fluorescent-antibody staining technique is applied for reading titers. The micromethod was found to be useful because of its sensitivity and rapidity.
Monitoring the Atmosphere in an Anaerobic Chamber
Authors: Sudo Sara Z. , Hersch Paul A.
Published: December 2020

The Couloximeter, a fuel cell designed to measure trace amounts of oxygen, was used to monitor the atmosphere in an anaerobic chamber. The device, easy to operate and to maintain, allowed both major and minor fluctuations in oxygen concentration to be measured. Using a hose attached to the outlet within the box, defective (ruptured) gloves were consistently distinguishable from intact gloves.
Ultrastructure of the Surface of
Rickettsia prowazeki
and
Rickettsia akari
Authors: Palmer Erskine L. , Martin Mary L. , Mallavia Louis
Published: December 2020

Negative-contrast electron microscopy revealed that the outer layer of the envelope of rickettsiae is composed of a matrix of tetragonally arranged subunits. The layer projects approximately 7 nm from the cell wall. It is suggested that this outer layer is analogous to the structure considered capsule-like in morphology.
Submerged Production, Purification, and Crystallization of Acid Carboxypeptidase from
Penicillium janthinellum
IFO-8070
Authors: Yokoyama Sadaji , Oobayashi Akira , Tanabe Osamu , Ichishima Eiji
Published: December 2020

Penicillium janthinellum
IFO-8070 produced an acid carboxypeptidase of molecular weight 51,000 in a liquid medium at 25 C. Maximum enzyme concentration was obtained within 3 to 6 days in a medium containing 2% wheat bran, 1% defatted soybean, and 1% KH
2
PO
4
; the initial pH was 2 to 4. When submerged aerobic conditions were used, a 51,000-molecular-weight acid carboxypeptidase was produced and no detectable amounts of 160,000-molecular-weight acid carboxypeptidase were produced. Acid carboxypeptidase with a molecular weight of 51,000 was purified 330-fold from koji culture to yield a crystalline protein which was demonstrated by disc electrophoresis to be homogeneous. The purification method included ammonium sulfate fractionation, Amberlite CG-50 chromatography, acetone fractionation, Amberlite CG-50 rechromatography, and concentration in a collodion bag. The specific activity of the enzyme was about three times more than that of the acid carboxypeptidase from
Aspergillus saitoi
.
Aspergillus flavus
Infection and Aflatoxin Production in Corn: Influence of Trace Elements
Authors: Lillehoj E. B. , Garcia W. J. , Lambrow M.
Published: December 2020

Distribution of trace element levels in corn germ fractions from kernels naturally infected with
Aspergillus flavus
and from kernels free of the fungus demonstrated an association between the presence of
A. flavus
and higher levels of metals.
A. flavus
production of aflatoxin on various autoclaved corn media showed that ground, whole corn was an excellent substrate; similar high levels of toxin were observed on full-fat corn germ but endosperm and defatted corn germ supported reduced yields. The influence of trace elements and their availability in defatted corn germ to
A. flavus
-mediated aflatoxin biosynthesis were measured. Enrichment of the substrate with 5 to 10 μg of manganese, copper, cadmium, or chromium per g of germ increased toxin yields. Addition of lead or zinc (50 to 250 μg/g) also enhanced toxin accumulation. Aflatoxin elaboration was reduced by the addition of 25 μg of cadmium per g or 500 μg of copper per g of germ.
Microculture Plaque Neutralization Test for California Group Arboviruses
Authors: Seawright Gary L. , Harding Gherry , Thomas Frederick C. , Hanson Robert P.
Published: December 2020

A microculture plaque neutralization test is described for California-group arboviruses that is as precise and quantitative as the standard test conducted in 60-mm petri dishes. It was shown that there was no significant between-panel or between-day variation in determinations and that a single pipette could be used for all serum-dilution levels within a titration without inoculum carry-over effect. The experimental protocol and statistical methods used produce 50% neutralization end points that meet the assumptions of parametric statistics. This permits the power and versatility of the analysis of variance to be exploited in testing for treatment effects in serological and immunological studies with viruses.
Corynebacterial Kidney Disease of Salmonids: Growth and Serological Studies on the Causative Bacterium
Authors: Bullock G. L. , Stuckey H. M. , Chen P. K.
Published: December 2020

Comparative growth studies of 10 isolates of the
Corynebacterium
of salmonid kidney disease were quantified on four media. Greatest cell yield was obtained from Mueller-Hinton medium with 0.1% L-cysteine hydrochloride. Serological tests, in which rabbit antisera used against typical bacteria strains showed all to be antigenically homologous, provided a reliable method of identification.
Chemical Disinfection of Holding-Tank Sewage
Authors: Sobsey Mark D. , Wallis Craig , Melnick Joseph L.
Published: December 2020

A number of chemical disinfectants were evaluated for their bactericidal and virucidal effectiveness in holding-tank sewage. It was found that the disinfection efficiencies of formaldehyde, benzalkonium chloride, cetylpyridinium chloride, and methylene blue were markedly improved if the pH of the sewage was raised from 8.0 to 10.5. When formaldehyde, benzalkonium chloride, and methylene blue were tested with either 2-week holding times with no sewage additions or 10-day holding times with daily sewage additions, disinfection effectiveness was maintained as long as the sewage pH was kept at 10.5 and the disinfectant concentration was kept at 100 mg/liter or more. Calcium hypochlorite, zinc sulfate, and phenol were found to be relatively ineffective disinfectants for holding-tank sewage.
Nutritional Features of the Intestinal Anaerobe
Ruminococcus bromii
Authors: Herbeck Janice L. , Bryant M. P.
Published: December 2020

Of six strains of
Ruminococcus bromii
studied, five grew in a minimal chemically defined medium containing minerals, NH
4
+
as nitrogen source, sulfide or sulfate as sulfur source, fructose as energy and carbon source, isobutyrate or 2-methylbutyrate and carbonic acid-bicarbonate as additional carbon sources, and the vitamins biotin, riboflavin, pyridoxine, vitamin B
12
(replaced by L-methionine), pantethine, and tetrahydrofolate. The strains also could utilize cysteine or thiosulfate but not methionine; and strain Z3 failed to use dithiothreitol, thioglycolate, sulfite, or β-mercaptoethanol as sole sources of sulfur. Mixtures of amino acids, peptides (Casitone), urea, nitrate, asparagine, or glutamine failed to replace NH
4
+
as N source. Three strains isolated from Americans were identical in nutritional features, whereas one from a Japanese and one from a South African native differed slightly in having requirements for fewer vitamins. One strain from the cecum of a sow grew well in a rumen fluid-supplemented medium but not in the various chemically defined media plus Casitone. The nutritional features suggest that the environment which selects
R. bromii
contains relatively little amino acid nitrogen and a relatively large amount of NH
4
+
-N and indicate that these bacteria must depend upon other bacteria such as those that produce NH
4
+
from urea or protein and those that produce branched-chain volatile acids to grow.
In Vitro System for Production of Mouse Mammary Tumor Virus
Authors: Fine D. L. , Arthur L. O. , Plowman J. K. , Hillman E. A. , Klein F.
Published: December 2020

An in vitro system for production, purification, and concentration of mouse mammary tumor virus is described. Monolayer cultures of C
3
H mouse mammary tumor cells propagated at 34 C in roller bottles in the presence of dexamethasone, a glucocorticoid hormone, release B-type particles which possess ribonucleic acid and a ribonucleic acid-dependent deoxyribonucleic acid polymerase. One thousandfold concentration by ultracentrifugation with subsequent gradient fractionation yielded > 7 × 10
10
particles per ml in the 1.16- to 1.18-g/ml region. Mouse mammary tumor virus produced in this system was free of detectable C-type virus.
Periplasmic Structure in
Saccharomyces rouxii
(Boutroux), an Osmophil
Authors: Arnold Wilfred N. , Garrison Robert G. , Boyd Karen S.
Published: December 2020

Electron micrographs of ultrathin sections of
S. rouxii
displayed electrondense, membrane-circumscribed structures between the protoplasmic membrane and the cell wall. These periplasmic bodies were numerous in cells from a 3-day culture and absent or rare in older cells. Periplasmic bodies were fewer and smaller (flattened) in specimens grown in a medium fortified with 10% sucrose; they were not detected in cells grown in 20% sucrose. A brief treatment with ethyl acetate caused the periplasmic bodies of young cells to become electron light. Periplasmic bodies were most prevalent in the regions of the bud scars and were often accommodated within large invaginations in the protoplasmic membrane. In general, conditions which favor the prevalence and electron density of periplasmic bodies are those which also mask the activity of β-fructofuranosidase in this species.
Continuous Culture Used for Media Optimization
Authors: Mateles R. I. , Battat E.
Published: December 2020

A technique is described in which continuous culture is used for the optimization of media in terms of growth-supporting ability. The technique consists of identifying growth-limiting nutrients by observing the reaction of the continuous system to injection of suspected growth-limiting nutrients into the growth vessel.
Criteria for Preparing, Evaluating, and Standardizing Iodinated Globulins for Radioimmunoassay Procedures
Authors: Hutchinson Harriet D. , Ziegler Donald W.
Published: December 2020

Procedures were examined for labeling immune globulins with radioactive iodine using chloramine-T as the oxidizing agent. The chloramine-T method was critically evaluated to establish the optimal conditions for preparing iodinated globulins with high specific radioactivities without impairing their immunospecificities for use in in vitro radioimmunoassays. The results showed that the use of 100 μg of chloramine-T per ml, 500 to 1,000 μCi of Na
125
I per mg of protein, and a 10-min oxidation reaction time produced globulins of both high specific radioactivities and immunospecificities. Criteria were established for evaluating and determining optimal concentrations of iodine-labeled globulin for use in radioimmunoassays. The results of this investigation indicated that the amount of labeled indicator globulin used in radioimmunoassays should be based upon protein concentration rather than radioactivity.
Detecting the Enterotoxigenicity of
Staphylococcus aureus
Strains
Authors: Robbins Ruth , Gould Sara , Bergdoll Merlin
Published: December 2020

An optimal sensitivity plate method for examining large number of staphylococcal strains for production of the known enterotoxins (A—E) is presented. Small volumes of relatively concentrated enterotoxin are produced by the semi-solid agar, cellophane-over-agar, or sac culture techniques. Detection of the enterotoxin in the supernatant fluid is accomplished with the optimal sensitivity plate method. In this method small plastic petri dishes (50 mm) were used for a modified Ouchterlony of high sensitivity.
Rubella Hemagglutination Inhibition: Removal of Nonspecific Agglutination Due to Manganous Chloride
Authors: Biano S. A. , Chang Te Wen , Daniels J. B.
Published: December 2020

Nonspecific inhibitors of rubella hemagglutination can be removed by treatment of sera with heparin-manganous chloride for use in the hemagglutination-inhibition test. After removal of nonspecific inhibitors by this procedure, an excess of manganous chloride may remain. This may cause the cells to agglutinate, thus obscuring the reading at low serum dilutions. This disadvantage can be overcome by the addition of sodium carbonate, which forms an insoluble compound with manganous chloride and does not interfere with antibody determination. The procedure presents a further refinement of the hemagglutination inhibition test for rubella by increasing specificity and sensitivity; it permits detection of antibody levels as low as 1:4 in sera.
Spoilage Association of Chicken Breast Muscle
Authors: McMeekin T. A.
Published: December 2020

The ability of pure cultures of bacteria isolated from spoiling chicken breast muscle to produce strong off-odors was tested by using sterile breast muscle sections. The incidence of organisms capable of producing strong off-odors and changes in flora during storage of naturally spoiling muscle at 2 C was traced, and the relationship between bacterial type and off-odor production was noted.
Irradiation of
Escherichia coli
in the Visible Spectrum with a Tunable Organic-Dye Laser Energy Source
Authors: Takahashi Patrick K. , Toups Harold J. , Greenberg David B. , Dimopoullos George T. , Rusoff Louis L.
Published: December 2020

Pulsed laser energy was shown to be effective in inhibiting the growth of
Escherichia coli
. The irradiation source was derived from a tunable organic-dye laser utilizing rhodamine 6G (590 � 5 nm) solutions as lasing media. The organisms, suspended in nutrient broth, were irradiated both with and without an exogenous photosensitizer. One photosensitizer (toluidine blue) did not appreciably alter the inhibitory effect observed. In the presence of acridine orange, however, some additional growth occurred.
Characterization of Hydrogen Sulfide-Producing Bacteria Isolated from Meat and Poultry Plants
Authors: McMeekin T. A. , Patterson J. T.
Published: December 2020

A survey of the types of aerobic organisms able to produce H
2
S on peptone iron agar (Levin, 1968), and commonly occurring in meat and poultry plants, revealed that these could be divided into four distinct groups. The ability of representative strains of each type to grow at low temperatures and cause off-odors on chicken muscle was examined. The results are discussed in relation to the role of these organisms in the psychrophilic spoilage of meat and meat products.
Ecology of Soil Arthrobacters in Clarion-Webster Toposequences of Iowa
Authors: Hagedorn Charles , Holt John G.
Published: December 2020

Toposequence variations in soil properties were characterized and related to variations in populations of total isolatable bacteria and arthrobacters. Increases in soil NO
3
-N, available phosphorous, NO
3
-N-producing power,
Arthrobacter
counts, and the percentage of the total counts represented by arthrobacters were correlated with decreases in soil acidity. The total bacterial counts were not correlated with soil acidity but were associated with percentage of soil organic matter and percentage of clay. The percentage of the total counts represented by arthrobacters was lowest at the summit position and increased downslope to the highest value in the toeslope position. Factor analysis of the data revealed that 67 to 81% of the total variance exhibited by all variables per site-sampling period could be accounted for by soil acidity, soil structure, soil fertility, soil moisture, and bacterial factors. A selective medium was developed for soil arthrobacters and tested on a wide variety of central Iowa soils to determine its potential as a medium for enumeration as well as isolation. The medium developed in this study was found to be superior to the other available direct-isolation media for soil arthrobacters.
Uptake and Elimination of Poliovirus by West Coast Oysters
Authors: Girolamo Rudolph Di , Liston John , Matches J.
Published: December 2020

Accumulation of poliovirus Lsc-2ab by West Coast oysters was determined by using a stationary seawater system, and depuration was determined by using both stationary and free-flow systems. Results indicate that these shellfish have the same pattern of accumulation and localization of viruses as do East Coast species. However, uptake appeared to occur more rapidly than described for East Coast shellfish. There appeared to be a gradual diffusion of virus from the digestive area into the body. Depuration was found to occur more rapidly and completely under free-flow conditions than in a stationary system.
Effect of Water Potential on Growth and Iron Oxidation by
Thiobacillus ferrooxidans
Authors: Brock Thomas D.
Published: December 2020

The effect of water potential on the growth of two strains of
Thiobacillus ferroxidans
was determined by adding defined amounts of sodium chloride or glycerol to the culture medium. The two strains differed slightly, and the most tolerant strain had a minimum water potential for growth of -15 to -32 bars when sodium chloride was used and -6 bars when glycerol was used. In another approach, the limiting water potential was determined by equilibrating small amounts of culture medium with atmospheres of relative humidities equivalent to specific water potentials, and the ability of the organism to grow and oxidize ferrous iron was determined. Under these conditions, which are analogous to those which might control water potential in a coal refuse pile or copper leaching dump, the lower limit at which iron oxidation occurred was -23 bars. The water potential of some coal refuse materials in which
T. ferrooxidans
was present were determined, and it was found that the water potentials at which the organism was active in these habitats were similar to those at which it was able to grow in culture. However, marked variation in water potential of coal refuse materials was found, presumably due to differences in clays and organic materials, and some coal refuse materials would probably never have water potentials at which the organism could grow. Some literature on the water potentials in copper leach dumps is reviewed, and it is concluded that control of water potential is essential to maximize the success of leaching operations. Because adequate drainage is necessary in a leach dump to ensure sufficient aeration, in many cases water availability in leach dumps may restrict the development of the bacterium necessary for the process.
Inexpensive Device for the Aerobic and Anaerobic Sampling of Microorganisms in Lake and Shallow Ocean Waters
Authors: Edwards R. M.
Published: December 2020

An inexpensive device suitable for sampling microorganisms in water and easily constructed from readily available laboratory equipment is described. The need to transfer subsamples to culturing flasks after collection is eliminated by partly filling the sampling vessels with growth medium prior to sampling. The device is readily adapted for sampling different volumes, is simple and quick to operate, and is suitable for use with prereduced media. Contamination from layers other than that being sampled is insignificant.
Isolation of
Vibrio parahaemolyticus
and
Vibrio alginolyticus
from Estuarine Areas of Southeastern Alaska
Authors: Vasconcelos G. J. , Stang W. J. , Laidlaw R. H.
Published: December 2020

The first reported isolations of halophilic vibrios, including
Vibrio parahaemolyticus
, from three seafood processing areas in Southeastern Alaska are described.
Demonstration of Virus in Groundwater after Effluent Discharge onto Soil
Authors: Wellings Flora Mae , Lewis Arthur L. , Mountain Carrol W. , Pierce L. Virginia
Published: December 2020

The survival of virus present in secondary effluents discharged into a cypress dome was studied. Isolations were made from concentrates of water drawn from 10-foot (304.80 cm) deep wells. Data presented show vertical and lateral virus movement as well as survival within the dome for 28 days during a period of heavy rains when no effluent was being applied. Due to the inefficiency of virus concentration procedures, it is proposed that much of the virus present was probably not demonstrated. A rapid, relatively inexpensive concentration technique for sewage influents and effluents is discussed.
Salmonella
Survival on Pecans as Influenced by Processing and Storage Conditions
Authors: Beuchat L. R. , Heaton E. K.
Published: December 2020

Survival of
Salmonella senftenberg
775W,
S. anatum
, and
S. typhimurium
during exposure to currently practiced, as well as abusive, pecan processing and storage conditions was studied. Thermal treatments normally carried out during the processing of pecans are inadequate to consistently destory salmonellae in highly contaminated inshell nuts. Pecan nut packing tissue was toxic to salmonellae, thus affording some protection against high initial contamination and subsequent survival of the organisms. Examinations of inoculated inshell pecans stored at -18, -7, 5, and 21 C for up to 32 weeks revealed that the extent of survival was inversely correlated to the storage temperature.
S. senftenberg
775W and
S. anatum
were not detectable on inshell nuts after 16 weeks of storage at 21 C. Little decrease in viable population of the three species was noted on inoculated pecan halves stored at -18, -7, and 5 C for 32 weeks. Due to organoleptic quality deterioration in pecan nutmeats at elevated temperatures, sterilization methods other than thermal treatment appear to be required for the elimination of viable salmonellae from pecan nuts.
Improved Medium for Lactic Streptococci and Their Bacteriophages
Authors: Terzaghi Betty E. , Sandine W. E.
Published: December 2020

Incorporation of 1.9% β-disodium glycerophosphate (GP) into a complex medium resulted in improved growth by lactic streptococci at 30 C. The medium, called M17, contained: Phytone peptone, 5.0 g; polypeptone, 5.0 g; yeast extract, 2.5 g; beef extract, 5.0 g; lactose, 5.0 g; ascorbic acid, 0.5 g; GP, 19.0 g; 1.0 M MgSO
4
·7H
2
O, 1.0 ml; and glass-distilled water, 1,000 ml. Based on absorbance readings and total counts, all strains of
Streptococcus cremoris, S. diacetilactis
, and
S. lactis
grew better in M17 medium than in a similar medium lacking GP or in lactic broth. Enhanced growth was probably due to the increased buffering capacity of the medium, since pH values below 5.70 were not reached after 24 h of growth at 30 C by
S. lactis
or
S. cremoris
strains. The medium also proved useful for isolation of bacterial mutants lacking the ability to ferment lactose; such mutants formed minute colonies on M17 agar plates, whereas wild-type cells formed colonies 3 to 4 mm in diameter. Incorporation of sterile GP into skim milk at 1.9% final concentration resulted in enhanced acid-producing activity by lactic streptococci when cells were inoculated from GP milk into skim milk not containing GP. M17 medium also proved superior to other media in demonstrating and distinguishing between lactic streptococcal bacteriophages. Plaques larger than 6 mm in diameter developed with some phage-host combinations, and turbid plaques, indicative of lysogeny, were also easily demonstrated for some systems.
Ultrastructure of Cell Envelopes of Bacteria of the Bovine Rumen
Authors: Cheng K. J. , Costerton J. W.
Published: December 2020

Most of the bacteria found in rumen fluid samples taken from cows fed hay, or a concentrate diet, had cell walls of the gram-negative type. Most were intact, with only a small proportion of lysed cells, and many of the cells contained electron-translucent cytoplasmic deposits similar to the carbohydrate reserve material described in pure cultures of rumen organisms. All of the bacteria observed in these samples had an external “coat” layer outside the outer membrane when fixed in glutaraldehyde and osmium, stained with uranyl acetate and lead citrate, and examined as sectioned material. These coat layers varied from thin (ca. 8 nm) structures to very extensive fibrous systems, sometimes including concentric arrangements and radial fibers extending up to 1,200 nm from the cell. The thin-coat layers sometimes exhibited a rough periodicity. In all, 10 different types of coat layers were distinguished on a morphological basis. It is proposed that these external coat layers have protective and adherence functions for the rumen bacteria in the environment.
Fluorescent-Antibody Study of Natural Finger-Like Zooloeae
Authors: Farrah Samuel R. , Unz Richard F.
Published: December 2020

Fluorescent-antibody techniques using
Zoogloea ramigera
106 antiserum were used to study fresh activated sludge flocs and finger-like zoogloeae in the microbial film that developed over stored samples of activated sludge. Few cells in fresh activated sludge reacted positively with the fluorescein-labeled antiserum. Finger-like zoogloeae containing reactive cells were readily observed in the microbial film layer over stored activated sludge. Certain of the natural finger-like projections were entirely composed of cells that reacted positively to the labeled
Z. ramigera
106 antiserum, whereas other projections were devoid of reactive cells.
Comparative Study of Four Microporous Filters for Concentrating Viruses from Drinking Water
Authors: Jakubowski Walter , Hill William F. , Clarke Norman A.
Published: December 2020

Four microporous virus-adsorbent filter media for recovering low levels of virus from 380 liters of drinking water were compared. In addition, two of the filter media were compared with 1,900 liters of drinking water. The filter media evaluated were MF nitrocellulose membranes (293 mm), AA Cox M-780 epoxy-fiberglass-asbestos disks (267 mm), K-27 yarn-wound fiberglass cartridges + AA Cox M-780 disks (127 mm), and Balston epoxy-fiberglass tubes (24.5 by 63.5 mm). The filters were used to concentrate seeded poliovirus from 380 liters of finished drinking water. Sodium thiosulfate was added to the drinking water to neutralize chlorine, and hydrochloric acid was added to adjust the pH to 3.5. Virus was eluted from the filters with glycine-NaOH buffer at pH 11.5. In terms of virus recovery efficiency, the filter media ranked Balston > Cox 267-mm > MF 293-mm ≃ K-27 + Cox 127-mm, but differences were slight. The Balston filters and holders were also superior to the other systems in terms of size, weight, cost, and handling factors. Experiments with 2- and 8-μm porosity Balston filters showed no statistically significant difference in virus recovery. Virus was readily detected by the Balston and the MF 293-mm systems at input levels of 12 to 22 PFU/1,900 liters. Preliminary experiments indicated that an elution pH lower than 11.5 may be satisfactory.
Membrane Filter Technique for Enumeration of Enterococci in Marine Waters
Authors: Levin M. A. , Fischer J. R. , Cabelli V. J.
Published: December 2020

A membrane filter procedure is described for the enumeration of enterococci in marine waters. The procedure utilizes a highly selective and somewhat differential primary isolation medium followed by an in situ substrate test for identifying colonies of those organisms capable of hydrolyzing esculin. The procedure (mE) was evaluated with known streptococci strains and field samples with regard to its accuracy, sensitivity, selectivity, specificity, precision, and comparability to existing methods. Essentially quantitative recovery was obtained with seawater-stressed cells of
Streptococcus faecalis
and
S. faccium
. Neither
S. bovis, S. equinus, S. mitis
, nor
S. salivarius
grew on the medium. The selectivity of the medium was such that a 10,000-fold reduction in background organisms was obtained relative to a medium which contained no inhibitors and was incubated at 35 C. About 90% of those typical colonies designated as enterococci confirmed as such and about 12% of the colonies not so designated were, in fact, identified as enterococci. Plate to plate variability across samples approximated that expected by chance alone. Verified recoveries of enterococci from natural samples by the mE procedure, on the average, exceeded those by the KF method by one order of magnitude.