bluuebunny/crossref_metadata_2025 huggingface dataset:
Inactivation of Kanamycin, Neomycin, and Streptomycin by Enzymes Obtained in Cells of
Pseudomonas aeruginosa
Authors: Doi Osamu , Ogura Michiko , Tanaka Nobuo , Umezawa Hamao
Published: December 2020

Ten strains of
Pseudomonas aeruginosa
were disrupted and centrifuged. The supernatant fluids from centrifugation at 105,000 ×
g
contained enzymes inactivating kanamycin, neomycin, and streptomycin in the presence of adenosine triphosphate. Kanamycin-inactivating enzyme was precipitated with ammonium sulfate at 66% of saturated concentration, and the inactivated kanamycin was shown to be kanamycin-3′-phosphate in which the C-3 hydroxyl group of 6-amino-6-deoxy-
d
-glucose moiety was phosphorylated. This is identical with kanamycin inactivated by
Escherichia coli
carrying R factor. Streptomycin-inactivating enzyme was precipitated with ammonium sulfate at 33% of saturated concentration.
Inactivation and Phosphorylation of Kanamycin by Drug-resistant
Staphylococcus aureus
Authors: Doi Osamu , Miyamoto Mitsuko , Tanaka Nobuo , Umezawa Hamao
Published: December 2020

The cell-free system of clinical isolates of drug-resistant
Staphylococcus aureus
inactivated kanamycin, and the inactivated product was identified with kanamycin-3′-phosphate, in which the C-3-OH of the 6-amino-6-deoxy-
d
-glucose moiety of kanamycin was phosphorylated.
Growth of
Chlorella sorokiniana
at Hyperbaric Oxygen Pressures
Authors: Richardson B. , Wagner Fred W. , Welch B. E.
Published: December 2020

The growth rate of
Chlorella sorokiniana
decreased in a linear fashion as the partial pressure of oxygen was increased from 711 to 1,478 mm of Hg. Under two atmospheres of oxygen pressure, growth ceased after 10 to 12 hr. This cessation of growth was not due to any permanent injury, as growth resumed when oxygen partial pressure was reduced to ambient levels. The inhibition occurred under both autotrophic and heterotrophic growth conditions and was not accompanied by an increase in cell size. The results indicated that the tolerance of
Chlorella
cells to elevated oxygen pressures was not an absolute immunity, and that inhibition of growth at very high oxygen pressures cannot be accounted for by an inhibition of photosynthesis alone.
Heat Resistance of
Salmonella
: the Uniqueness of
Salmonella senftenberg
775W
Authors: Ng Henry , Bayne Henry G. , Garibaldi John A.
Published: December 2020

Of approximately 300 cultures of
Salmonella
, representing 75 different serotypes, none was found to be as heat-resistant as
S. senftenberg
775W. However,
S. blockley
2004 was 5 times more heat-resistant and
S. senftenberg
775W was 30 times more heat-resistant than
S. typhimurium
Tm-1, the reference strain in this study. All other strains of
Salmonella
tested, including 19 strains of
S. senftenberg
and 7 strains of
S. blockley,
had decimal reduction times at 57 C of about 1 min, equivalent to that of the reference organism, Tm-1. As observed in other bacterial species, strain 775W is more heat-sensitive in the log phase than in the stationary phase of growth. Cells from cultures grown at 44 C were more heat-resistant than those grown at either 35 or 15 C; the medium of growth, whether minimal or complex, made no appreciable difference in heat resistance. Cells from cultures limited by a carbon source were killed at a much slower rate than those limited by a nitrogen source and exhibited a 1-hr lag at 55 C before a significant rate of kill was attained. For any given set of growth conditions, strain 775W was always more heat-resistant than another strain of
S. senftenberg,
197B, which has normal heat resistance.
Vacuum-cleaning System for Isolation Chambers
Authors: Yale Charles E.
Published: December 2020

To encourage the utilization of the isolation chamber as a research tool, the cost of its use should be lowered. Methods and devices must be developed which make more efficient use of the space within the isolator and allow the operator to work more effectively in this confined area. A simple vacuum-cleaning system is described; it consists of a nozzle and flexible hose which connect through the isolator wall to an externally placed waste tank, attached by way of its outlet filter to a source of vacuum. The cylindrical waste tank [48 inches (1.219 m) high and 36 inches (0.914 m) in diameter] was sterilized in a large autoclave. During a 9-month test period, the system was used to remove soiled corncob bedding from a large isolator containing 90 adult monocontaminated rats. During this period, the microbial flora of the isolator was unchanged, and the time required to clean the cages was reduced by 50%. This vacuum-cleaning system is a safe, convenient, and economical means of increasing the efficiency of an isolation chamber.
Production and Properties of α-L-Arabinofuranosidase from
Corticium rolfsii
Authors: Kaji Akira , Yoshihara Osamu
Published: December 2020

When
Corticium rolfsii
is grown under aerobic conditions in a medium containing one of several simple sugars or polysaccharides, it release α-L-arabinofuranosidase into the culture fluid. Araban and bran extract were found to be the most effective carbon sources in stimulating the production of the enzyme. Pectin and arabinose stimulated the production of the enzyme to a lesser degree, whereas xylose, glucose, galactose, and sucrose caused the formation of a relatively small amount of α-L-arabinofuranosidase. α-L-Arabinofuranosidase was demonstrated by its ability to hydrolyze phenyl-α-L-arabinofuranoside, araban, and arabinoxylan. The
p
H optimum of the enzyme was 2.5. At
p
H values of 2 to 9, the enzyme lost less than 15% of its activity during a 72-hr period at 2 C. At 70 C, its stability was greatest at
p
H values of 4 to 6.
Influence of Temperature on Glucose Utilization by
Pseudomonas fluorescens
Authors: Palumbo Samuel A. , Witter Lloyd D.
Published: December 2020

The influence of temperature on the conversion of glucose into cell material and into energy for maintenance was determined for
Pseudomonas fluorescens
by a steady-state turbidity method and by a substrate utilization method. Conversion of glucose into cell material was measured as yield; conversion of glucose into energy for maintenance was measured as specific maintenance, the minimum dilution rate in continuous culture below which a steady state is not possible. The values obtained by the two methods were nearly identical; with both, the yield and specific maintenance decreased with decreasing temperature. The specific maintenance consumption rate (milligrams of glucose taken up per milligram of cell dry weight per hour at zero growth) was also calculated by the substrate utilization method and found to decrease with decreasing temperature. However, the amount of glucose consumed per generation for maintenance increased with decreasing temperature. This increased glucose consumption for maintenance may provide a partial explanation for the decrease in yield at low temperatures. Small amounts of glucose were also converted into pigment at all temperatures tested, with the greatest amount formed at 20 C.
Effects of Systemic Demethylchlortetracycline on Human Cutaneous Microflora
Authors: Marples R. R. , Williamson P.
Published: December 2020

The aerobic flora of the axilla and forehead of 20 normal human subjects was studied through a 3-week course of 600 mg of demethylchlortetracycline daily and a 3-week follow-up. In general in the axilla, an initial fall in bacterial density was followed by recovery in numbers due to the proliferation of resistant coagulase-negative cocci and diminution of the lipophilic diphtheroid group of bacteria within 1 week of treatment. During the remainder of the treatment period, the flora was essentially stable in both density and composition. In the follow-up phase, the initial flora was slowly re-established but resistant cocci persisted for more than 3 weeks. On the forehead the fall in density was slower and recovery during treatment was incomplete. Resistant coagulase-negative cocci became dominant and persisted through the follow-up phase. In two individuals, temporary colonization of the axilla by
Staphylococcus aureus
was seen.
Method for Eliminating Anticomplementary Activity in Animal Sera
Authors: Bucca Matthew A. , Alder Ann O.
Published: December 2020

A method is described for removing the anticomplementary activity of sera by the addition of normal porcine serum. Results of sera taken from four animal species immunized with influenza, coxsackievirus, echovirus, and vaccinia viral antigens are presented.
Evaluation of Media for Differentiating Nonfermenting Gram-negative Bacteria of Medical Significance
Authors: Gilardi Gerald L.
Published: December 2020

An evaluation was made of media and tests used for differentiating nonfermenting gram-negative bacteria encountered in medical bacteriology in order to determine those diagnostic procedures most useful in identifying these bacteria. The organisms examined included
Alcaligenes faecalis, A. odorans var. viridans, Moraxella duplex (Mima polymorpha var. oxidans), Acinetobacter anitratum (Herellea vaginicola), A. lwoffi (Mima polymorpha), Pseudomonas fluorescens, P. putida, P. maltophilia, P. pseudomallei, P. stutzeri, P. alcaligenes,
and atypical strains of
P. aeruginosa.
The media and tests evaluated included Sellers' medium; Hugh and Leifson's OF medium; acid production from 10% lactose infusion agar; gluconate oxidation; starch, aesculin, and Tween 80 hydrolysis; lysine decarboxylase, arginine dihydrolase, deoxyribonuclease, and tyrosinase activity; tolerance to triphenyl tetrazolium chloride, cetrimide, cadmium sulfate, 2.5% and 6.5% sodium chloride, and
p
H 5.6; utilization of glucose, acetamide, and malonate.
Pseudourea, 2,2′-(9,10-Anthrylenedimethylene) bis-(2-thio-, dihydrochloride) Dihydrate: Microbiological Assay and Tissue Distribution Studies in Mice
Authors: Pittillo Robert F. , Woolley Carolyn
Published: December 2020

A microbiological assay for pseudourea, 2,2′-(9,10-anthrylenedimethylene)bis-(2-thio-, dihydrochloride) dihydrate (NSC 56054), a new anticancer agent, has been developed and tissue distribution studies in mice have been performed.
Isolation of Human Enterovirus from Mussels
Authors: Bendinelli M. , Ruschi A.
Published: December 2020

Mussels maintained in sea water heavily polluted with domestic raw sewage have been found to harbor human enteroviruses.
Antibacterial Properties of 3,3′,5,5′-Tetrachlorotetranitrodiphenylamine
Authors: Fritsch A. J. , Moore C. E. , Meyer T. S. , Shklair I. L. , Devine L. F.
Published: December 2020

An analogue of tetramethyldicrylamine, 3,3′,5,5′-tetrachlorotetranitrodiphenylamine, was synthesized and tested in vitro for its antibacterial activity.
Control Mechanisms Operative in a Natural Microbial Population Selected for its Ability to Degrade L-Lysine. I. Effect of Glucose in Batch Systems
Authors: Grady C. P. L. , Gaudy A. F. , Gaudy Elizabeth T.
Published: December 2020

A natural microbial population was selected in a medium containing L-lysine as the sole carbon source and ammonia as a nitrogen source. Cells were harvested from a batch-operated fermentor containing lysine and were grown through one transfer on lysine, glucose, or a mixture of lysine and glucose. By comparing the substrate removal rates and enzymatic capabilities of the cells, it was determined that the inducible enzyme system responsible for lysine degradation was subject to catabolic repression. Inhibition of the activity of preformed enzyme(s) played only a minor role. Preinduction by lysine offered only a small degree of protection against repression. The removal of ammonia nitrogen from the system did not overcome the effect of glucose.
Incidence of Mucoid
Pseudomonas aeruginosa
from Clinical Sources
Authors: Doggett Robert G.
Published: December 2020

The high frequency of pulmonary infection by mucoid strains of
Pseudomonas aeruginosa
in patients with cystic fibrosis can be interpreted to represent an apparent mutation resulting from environmental factors within the host.
Diluent Composition and the Recovery of
Escherichia coli
Authors: Weiler William A. , Hartsell S. E.
Published: December 2020

The ability of 0.1% Trypticase (BBL) to maximize recovery of frozen
Escherichia coli
on Violet Red Bile Agar is presented.
Elimination of Toxicity from Polyvinyl Trays After Sterilization with Ethylene Oxide
Authors: Rueter A. , Schleicher J. B.
Published: December 2020

Ethylene oxide (ETO) sterilization of polyvinyl trays used in an antiviral screening program was initiated to overcome seasonal outbreaks of bacterial and mycotic contamination of tissue culture cells. Trays sterilized by 100% ETO for 5 hr after 48 hr of prehumidification, or by 12% ETO plus 88% Freon 12 for 1, 3, 5 or 18 hr, followed by various methods of aeration, were seeded with several types of tissue culture cells and examined for contamination, toxicity, and monolayer quality. A 1-hr exposure in 12% ETO plus 88% Freon 12 was adequate for sterilization, although residual toxicity for tissue cultures remained. A 7-day aeration period at 37 C was sufficient to eliminate toxicity and allow the growth of good monolayers of WI-38, HEp-2 and primary bovine kidney cells. Sterilization with 100% ETO required 14 days of aeration at 37 C to eliminate cytotoxicity. Increased residual toxicity resulting from longer ETO sterilization periods required longer aeration times at 37 C or higher aeration temperatures for detoxification.
Therapy of Staphylococcal Infections in Monkeys. IV. Further Comparison of Triacetyloleandomycin and Erythromycins
Authors: Saslaw Samuel , Carlisle Harold N. , Marietti Maurice
Published: December 2020

Intravenous inoculation of a penicillin-resistant, phage type 80/81 staphylococcus caused lethal infection in 8 of 15 untreated monkeys. Daily intragastric administration of 50 mg/kg of triacetyloleandomycin, erythromycin estolate, and erythromycin ethylsuccinate was followed by mortalities of 0 of 16, 3 of 16, and 3 of 10, respectively. At dose levels of 25 and 12.5 mg/kg, none of 7 and 4 of 7 receiving triacetyloleandomycin and erythromycin estolate, respectively, died, as compared to 3 of 4 deaths in controls. In vitro sensitivity data and serum antibacterial levels would suggest that triacetyloleandomycin would be the least effective therapeutically. However, this prediction was not fulfilled in these studies of experimental infections in monkeys wherein triacetyloleandomycin was a very effective antimicrobial agent.
Sulfadiazine Susceptibility Patterns of
Neissera meningitidis
Group Y
Authors: Oughton Carl J. , Robinson John A. , Meekins William E.
Published: December 2020

Four of 46
Neisseria meningitidis
group Y strains (8.6%) were resistant to 1.0 mg of sulfadiazine per 100 ml when tested by the agar plate-dilution technique.
Resistance to Bacterial Infection Induced by Statolon and Pyran
Authors: Pindak Frank F.
Published: December 2020

The antibacterial properties of statolon and pyran were compared with those of bacterial endotoxin and found to be similar. Although high resistance was transient, it was followed by immunity of the same order as in mice infected without pre-treatment with the interferon inducers.
Effect of Light Intensity and Thickness of Culture Solution on Oxygen Production by Algae
Authors: Shuler R. L. , Affens W. A.
Published: December 2020

Data from a small cylindrical culture unit with variable annular culture chambers indicate that (i) the rate of oxygen evolution by an algal culture in the linear phase of growth is a logarithmic function of light intensity, and (ii) the rate of oxygen evolution per unit volume of suspension is linearly related to the reciprocal of culture thickness. These two relationships have been combined in an empirical equation which gives the expected variation of the oxygen production rate with light intensity, culture thickness, and suspension volume. The applicability of this equation has been tested on a larger, multilight culture unit in this laboratory. The agreement between the experimental and calculated oxygen production rates was very satisfactory, suggesting that the equation is not limited to a particular culture unit but may have wide applicability. The efficiency of the culture unit from the standpoint of oxygen output (chemical energy) relative to electrical energy to supply the light source has been calculated, and the maximum value of 0.51% was obtained. The energy to run auxiliary equipment was not a factor in these calculations. The maximum efficiency in converting light energy to chemical energy was approximately 12%. An extrapolation of the experimental results suggests that approximately 2 ft
3
and 30 kw would be required to provide the oxygen needs of one man.
Separation of
Treponema pallidum
from Tissue Debris Through Continuous-Particle Electrophoresis
Authors: Schmale John D. , Kellogg Douglas S. , Miller Curtis E. , Schammel Patricia , Thayer James D.
Published: December 2020

Treponema pallidum
can only be cultured in living animal tissue, such as rabbit testes. However, the extract of these organisms from the testicular material leaves the
T. pallidum
contaminated with tissue debris. This paper describes the separation of
T. pallidum
from the debris by continuous-particle electrophoresis. The importance of equilibration time before electrophoresis is discussed.
Radiation Treatment of Foods
Authors: Epps N. A. , Idziak Edmund S.
Published: December 2020

Salmonellae resistant to gamma irradiation were developed by repeated irradiation and subculturing in a nutrient broth-yeast extract medium. Few differences were noted in the biochemical characteristics of parent and resistant cultures; however, microculture studies revealed variations in morphology and in cell division patterns. A considerable decrease in pathogenicity for day-old chicks was apparent with resistant cultures, but their phenol-water extracts were as toxic as parent material for 10-day chick embryos. Five serial chick passages did not reverse the reduced pathogenicity or aberrant morphology of a resistant
Salmonella typhimurium
culture. Results of phage typing of both parent and serially irradiated
S. typhimurium
were inconclusive, whereas the O-1 genus-specific phage lysed all parent serotypes tested but only one of the serially irradiated cultures. Agglutination of parent
S. typhimurium
cells with their homologous rabbit antiserum was unaffected by prior absorption with resistant strains. The results indicate that radiation recycling altered
Salmonella
into strains of lesser public health significance.
New Antibacterial Agent Isolated from the Avocado Pear
Authors: Néeman I. , Lifshitz A. , Kashman Y.
Published: December 2020

A group of eight new long-chain aliphatic compounds recently isolated from the avocado and some derivatives thereof were tested for antibacterial activity on 13 different species of bacteria and a yeast. Some of these compounds inhibited the growth of microorganisms. 1,2,4-Trihydroxy-n-hepadeca-16-en was found to be the most active, inhibiting certain gram-positive bacteria at 4 μg/ml.
Variables of the Rubella Hemagglutination-Inhibition Test System and Their Effect on Antigen and Antibody Titers
Authors: Schmidt Nathalie J. , Lennette Edwin H.
Published: December 2020

A systematic study was made of certain variables of the rubella hemagglutination-inhibition (HI) test system and their effect on antigen and antibody titers. Erythrocytes from pigeons and 1-day-old chicks gave similar antigen and antibody titers, but goose erythrocytes gave lower titers. Indicator erythrocytes could be stored in Alsever's solution at 4 C for as long as 2 weeks without losing sensitivity in hemagglutination (HA) and HI tests. Antigen titers varied by eightfold or more in different diluent systems; titers were generally higher at
p
H 6.2 than at
p
H 7.2. A diluent without Ca
2+
gave antigen titers as high as those obtained in diluents with added Ca
2+
ions. Antibody titers also varied in different diluent systems. HEPES diluents at
p
H 6.2 gave higher antibody titers than those obtained in other diluents, but occasional “false-positive” inhibition reactions were seen. Kaolin suspended in borate saline at
p
H 9.0 effectively removed inhibitor from sera without absorbing specific antibody, but at
p
H 7.3 it removed various amounts of specific antibody. Antibody titers of sera treated with kaolin at
p
H 9.0 were similar to those of sera treated with heparin-MnCl
2
; treatment with dextran sulfate-CaCl
2
gave lower antibody titers. Antigens varied widely in sensitivity for detecting HI antibody and in the ability to detect diagnostically significant increases in antibody. Sensitivity in detecting antibody was not related to the HA titer of the antigens. Tween-ether-treated antigens gave lower antibody titers but were more reliable than corresponding untreated antigens for serological diagnosis of infection.
Regression Curve Analysis of Cephalosporin Activity
Authors: Washington John A. , Yu Pauline K. W.
Published: December 2020

Regression lines were calculated for cephalothin, cephalexin, and cephaloridine by relating zone diameters of inhibition to minimal inhibitory concentrations (MIC) obtained in Mueller-Hinton agar and in Trypticase Soy Agar. A regression line was calculated for cephaloglycin by obtaining MIC values in Trypticase Soy Agar at
p
H 6.6. Regression lines calculated from MIC values in Mueller-Hinton agar were practically superimposable on those based on MIC values in Trypticase Soy Agar. Organisms susceptible by disc testing to cephalothin were usually susceptible to cephalexin and cephaloridine.
Survey of the Sensitivity of Microorganisms to Rubratoxin B
Authors: Hayes A. Wallace , Wyatt Elwanda P.
Published: December 2020

Of the 133 microorganisms tested,
Tetrahymena pyriformis
and
Volvox aureus
were the most sensitive to rubratoxin B, being inhibited at 25 and 50 μg/ml, respectively.
Rapid Sensitive Assay for Interferons Based on the Inhibition of MM Virus Nucleic Acid Synthesis
Authors: Allen Patton T. , Giron David J.
Published: December 2020

A method for assaying mouse interferon based on the inhibition of viral ribonucleic acid (RNA) synthesis was devised. The amount of MM virus and RNA synthesized in interferon-treated L-cell cultures was determined by measuring the amount of
3
H-uridine converted into a trichloroacetic acid-insoluble form after treatment of the infected cultures with 2.5 μg of actinomycin D per ml. The amount of RNA synthesized was inversely related to the concentration of interferon used for treatment. A linear dose-response regression curve was obtained by plotting the log of the amount of RNA made, expressed as a percentage of the control, versus the log of the reciprocal of the interferon dilution. A unit of interferon was defined as that concentration which inhibited nucleic acid synthesis by 50% (INAS
50
). The concentration of mouse interferon could be determined within 24 hr. This assay method, on the average, was approximately half as sensitive as the method which measured the 50% reduction of MM virus plaque number (PDD
50
-MM method), but was, on the average, almost 1.7 times as sensitive as the PDD
50
-VSV method. It averaged approximately 20 times the sensitivity of the methods which used as end points the 70% reduction in yield of MM virus or the complete inhibition of cytopathic effect by MM virus. The reproducibility of the INAS
50
technique was tested in two ways. (i) Four independent assays of an interferon specimen were performed with replicate cultures. The standard deviation was 11.2% of the mean titer. (ii) On different dates, one interferon specimen was assayed seven times and another was assayed four times. The standard deviations were 21.5 and 26.6% of the respective mean titers.
Pectic Acid Lyases of
Bacillus polymyxa
Authors: Nagel C. W. , Wilson T. M.
Published: December 2020

Four enzymes were separated from an extracellular preparation of
Bacillus polymyxa
by carboxymethylcellulose column chromatography. The
p
H optima were 8.3 to 8.5, 8.7 to 8.9, 9.2 to 9.4, and 9.5 to 9.6. All of the enzymes required calcium ion for maximum activity, whereas strontium ion was only partially effective in stimulating activity. Cobalt was the only other cation tested which was effective in two of the enzymes. The lyases seem to attack a calcium salt-bridged substrate.
K
m
and
V
m
data of the four enzymes on various oligomers are presented as well as paper chromatographic evidence of preferred sites of attack. All of the enzymes are endo-enzymes which, based upon their characteristics, were classed into two types.

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Effect of Bile and Desoxycholate on Gram-Negative Anaerobic Bacteria
Authors: Shimada Kaoru , Sutter Vera L. , Finegold Sydney M.
Published: December 2020

The bile tests for characterizing gram-negative anaerobic bacilli were reevaluated in prereduced anaerobically sterilized peptone-yeast-glucose broth, in thioglycollate broth, and on blood agar plates. Blood agar plates were unsatisfactory. The combination of 20% bile with 0.1% desoxycholate inhibited
Fusobacterium, Bacteroides melaninogenicus
, and
B. oralis
and sometimes
Sphaerophorus necrophorus
, but not
B. fragilis
or other
Sphaerophorus
species studied. Ten per cent bile with 0.05% desoxycholate was less satisfactory. There was no significant difference between fresh and commercial powdered bile. Desoxycholate (0.1% in thioglycollate broth) inhibited
B. fragilis, Fusobacterium, B. melaninogenicus, B. oralis
, and
S. necrophorus
, but not
S. varius
or
S. mortiferus/S. ridiculosus
. The bile and desoxycholate tests are simple to perform and helpful for characterization and classification of gram-negative anaerobic bacilli.
Comparison of Two Plating Media for Detection of
Salmonella
from Swine Tissues
Authors: Harrington Rube , Ellis Edwin M.
Published: December 2020

Xylose-lysine-Brilliant Green-agar and Brillian Green-sulfadiazine-agar were used to isolate salmonellae from swine tissues. There was no significant difference between the efficiency of the two media.
Additional
Salmonella
Serotype:
Salmonella enteritidis
ser. Madigan (44:c:1,5)
Authors: McElrath Hunter B. , Back Andrew E.
Published: December 2020

The antigenic composition of a new
Salmonella
type (44:c:1,5) isolated from the stool of an infant is described.
Injury of Bacteria by Sanitizers
Authors: Scheusner D. L. , Busta F. F. , Speck M. L.
Published: December 2020

Injury of test cultures was quantitated by differences in colony counts obtained with a complete medium and those obtained on conventional selective media.
Staphylococcus aureus, Streptococcus faecalis
, and several strains of
Escherichia coli
were injured when exposed to the quaternary ammonium compound methylalkyltrimethyl ammonium chloride. Representative hypochlorite sanitizers also caused injury of
E. coli
ML30. Sanitizer concentration appeared to be the main factor in the cause of death and injury, a higher concentration being needed to cause death. Increases in temperature did not result in substantial increases in injury; however, the lethal effect was greater at higher temperatures. Varying the cell concentration from 10
7
to 10
9
cells per ml did not change the fraction of cell population killed or injured. The inability or failure of common selective media to detect injured bacteria in food could have serious public health consequences.
Inhibition of Injured
Escherichia coli
by Several Selective Agents
Authors: Scheusner D. L. , Busta F. F. , Speck M. L.
Published: December 2020

A population of
Escherichia coli
ML30 cells was exposed to a quaternary ammonium compound, and injury to the cells was measured by a comparison of counts on Trypticase Soy Agar and Violet Red Bile Agar. Substantial injury could not be detected with a minimal medium. The ingredients of Violet Red Bile Agar were tested against damaged cells. The bile salts mixture alone in the medium prevented as many injured cells from growing as did any combination of the selective agents and inhibited as many injured bacteria as were inhibited by Violet Red Bile Agar itself. These dyes and salts were similarly assayed in minimal agar, and comparable results were obtained. Individual bile salts and other potential selective agents were added to the minimal medium, and the media were tested for inhibition of injured
E. coli.
Sodium deoxycholate was the bile salt most inhibitory to damaged
E. coli
cells.
Reagent Strips and Conventional Tests for Acid Production from Mannitol and Coagulase Activity of
Staphylococcus
: a Comparative Study
Authors: Anandam Ernest J.
Published: December 2020

A total of 244
Staphylococcus
strains were tested simultaneously for acid production from mannitol and for coagulase activity with reagent-impregnated paper strips and with their conventional counterparts. Significant correlation was obtained with 97.9% of the strains for mannitol and with 95% for the coagulase test. The paper strip method is a combined test for both mannitol and coagulase tests, thus making it more convenient and simpler than conventional methods. The results are obtained rapidly within 6 hr by the paper strip method. However, as the paper strip method is designed for the aerobic system, the conventional tests were also carried out under aerobic conditions to compare the results.
Antibodies to Epstein-Barr Virus in a Burkitt's Lymphoma Cell Line in Taiwan Monkeys (
Macaca cyclopis
)
Authors: Chu Chien-Ts , Yang Czau-Siung , Kawamura Akiyoshi
Published: December 2020

The prevalence of Taiwan monkeys with antibodies to Epstein-Barr virus, as detected by the indirect immunofluorescence technique, was lower than that of healthy persons in Taiwan.
Hospital Sanitation: the Massive Bacterial Contamination of the Wet Mop
Authors: Westwood John C. N. , Mitchell Mary A. , Legacé Suzanne
Published: December 2020

Following the demonstration of massive spread of bacterial contamination throughout the hospital by the wet-mopping techniques in use, quantitative studies were undertaken to determine the source of contamination and to institute measures of control. It was found that mops, stored wet, supported bacterial growth to very high levels and could not be adequately decontaminated by chemical disinfection. Laundering and adequate drying provided effective decontamination, but build-up of bacterial counts occurred if mops were not changed daily or if disinfectant was omitted from the wash-water. Recommendations were based upon the experimental findings.
Growth of
Aspergillus repens
in Flue-Cured Tobacco
Authors: Welty Ronald E. , Nelson Larry A.
Published: December 2020

In laboratory tests, flue-cured tobacco inoculated with
Aspergillus repens
was stored at 75, 80, 85, 87, and 95% relative humidity at 20 and 30 C. Samples were taken weekly for 4 weeks and evaluated for mold growth (colony count) and moisture content (MC). The weekly rate of fungus increase was slower at 20 C than at 30 C. Tobacco at 20 C with MC between 25 to 30% supported a slight to moderate increase in
A. repens
after 3 weeks of storage. However, tobacco at the same MC stored at 30 C was subject to rapid invasion by the fungus in as few as 1 to 2 weeks. Tobacco with MC above 30% stored at either 20 or 30 C became moldy in about 1 week. A mold index is proposed for evaluating populations of
A. repens
in tobacco.
Antifungal Activity of Selected Benzimidazole Compounds
Authors: Maxwell W. A. , Brody G.
Published: December 2020

The comparative antifungal activity of four benzimidazole compounds was determined against 11 fungi.
Microorganisms in Unamended Soil as Observed by Various Forms of Microscopy and Staining
Authors: Casida L. E.
Published: December 2020

A light-diffraction microscope was modified to allow sequential viewing of the microorganisms in a soil smear by transmitted, reflected, and reflected-polarized incandescent light and by reflected ultraviolet light. Observations were also made by conventional incandescent and ultraviolet transmitted-light microscopy. All results for the various forms of bright-field microscopy with stained and unstained soils were in agreement, but they differed from the results obtained for two types of ultraviolet-fluorescence microscopy. The latter proved to be nonspecific for in situ soil microorganisms. Capsule-like areas were noted surrounding many of the resident microbial cells of soil when viewed by the various forms of bright-field microscopy. These areas could not be stained or removed by a variety of treatments, but they apparently often did take up stain after in situ soil growth had been initiated. It was concluded that these areas are not capsules but may represent a structural component of nonmultiplying microbial cells in soil.
Microbiological Study of Copiamycin
Authors: Seiga Kanji , Yamaji Kunihiko
Published: December 2020

Copiamycin, an antibiotic agent, has shown in vitro activity against
Candida albicans, Torulopsis glabrata
, and
Trichomonas vaginalis.
Local administration of copiamycin to mice inoculated intraperitoneally with protozoa reduced the per cent of infection as measured by decreased abscess formation. This antibiotic has had little effect on the glucose oxidation by protozoa. Its action on anaerobic glucose metabolism in these organisms was equal to that of aminitrozole and azalomycin F. From these results we conclude that copiamycin is an effective antifungal and antitrichomonal agent equivalent in activity to azalomycin F.
Documents of Antibiotic Assays
Authors: Van Dijck Paul J.
Published: December 2020

A new technique is described, in which a copy machine (Rank-Xerox) is used for instantaneous reproduction of biological assays.
Antibiotic Synthesis and Morphological Differentiation of
Cephalosporium acremonium
Authors: Nash C. H. , Huber F. M.
Published: December 2020

In submerged cultures,
Cephalosporium acremonium
exists in four morphological forms: hyphae, arthrospores, conidia, and germlings. The phase of hyphal differentiation into arthrospores coincides with the maximum rate of β-lactam antibiotic synthesis. Furthermore, arthrospores, separated by density-gradient centrifugation, possess 40% greater antibiotic-producing activity than any other morphological cell type. In a series of mutants, each with an increased potential to produce β-lactam antibiotics, differentiation into arthrospores was proportional to the increased titer of these antibiotics. Thus, arthrospores exhibit enhanced synthesis of β-lactam antibiotics and appear to be a determining factor in high-yielding mutants. Since a non-antibiotic-producing mutant readily differentiated into arthrospores, antibiotic synthesis and cellular differentiation are not obligately related.
Two-Tube Test for the Rapid Identification of Prompt Lactose-Fermenting Genera Within the Family
Enterobacteriaceae
Authors: Closs O.
Published: December 2020

One hundred and fifty-nine prompt lactose-fermenting strains of
Enterobacteriaceae
were tested for H
2
S production, ornithine decarboxylase activity, motility, and citrate utilization by using two different sets of test media. It was shown that the three tests first mentioned could be carried out in a single tube, the results being as reliable as when each was done separately. Simmons medium was preferred for the detection of citrate utilization. Since these four tests require only two tubes, they are considered more convenient in routine diagnostics. A combined medium for the detection of H
2
S production and motility is described.
Multi-Biochemical Test System for Distinguishing Enteric and Other Gram-Negative Bacilli
Authors: Elston Harry R. , Baudo Judith A. , Stanek Joann P. , Schaab Mercedes
Published: December 2020

A multi-biochemical test system consisting of nine tests, entitled Enterotube, was evaluated in parallel with conventional tests to determine its value in the identification of enteric and certain other gram-negative bacilli. The 242 bacterial strains studied were from a variety of pathological specimens and from our culture collection. When the results with individual tests represented in both test systems were compared, no discrepancies were noted in the indole test, and one discrepancy was recorded for dextrose. In 7 of 242 hydrogen sulfide tests, 3 of 242 phenylalanine tests, 22 of 242 urease tests, 15 of 242 dulcitol tests, 12 of 242 lactose tests, 27 of 217 lysine decarboxylase tests, and 5 of 242 citrate tests, the Enterotube results were contrary to those obtained with conventional methods. The lysine decarboxylase test in the Enterotube posed a problem of interpretation and readability and is not an acceptable alternative to the conventional methods. Fifteen of the strains studied were incorrectly identified by the Enterotube system and four could not be differentiated from other closely related strains.
Salmonella
could be identified as to group, whereas
Shigella
strains were frequently misidentified as
Escherichia.
The Enterotube method is simple and convenient, and all media are inoculated at once from a single colony.
Metabolic Factors Affecting Enhanced Phosphorus Uptake by Activated Sludge
Authors: Boughton William H. , Gottfried Richard J. , Sinclair Norval A. , Yall Irving
Published: December 2020

Activated sludges obtained from the Rilling Road plant located at San Antonio, Tex., and from the Hyperion treatment plant located at Los Angeles, Calif., have the ability to remove all of the orthophosphate normally present in Tucson sewage within 3 hr after being added to the waste water. Phosphorus removal was independent of externally supplied sources of energy and ions, since orthophosphate and
32
P radioactivity were readily removed from tap water, glass-distilled water, and deionized water. Phosphorus uptake by Rilling sludge in the laboratory appears to be wholly biological, as it has an optimum
p
H range (7.7 to 9.7) and an optimum temperature range (24 to 37 C). It was inhibited by HgCl
2
, iodoacetic acid,
p
-chloromercuribenzoic acid, NaN
3
, and 2, 4-dinitrophenol (compounds that affect bacterial membrane permeability, sulfhydryl enzymes, and adenosine triphosphate synthesis). Uptake was inhibited by 1% NaCl but was not affected by 10
−3
m
ethylenediaminetetraacetic acid disodium salt (a chelating agent for many metallic ions).
Clinical Evaluation of Kethoxal Against Cutaneous Herpes Simplex
Authors: Underwood G. E. , Nichol F. R.
Published: December 2020

A 2.5% preparation of kethoxal in cream was compared with the cream placebo for efficacy against cutaneous herpes simplex in a double-blind clinical study. The kethoxal formulation was not significantly more effective than the placebo. This conclusion was based on subjective impressions of the patients, observations by the physicians, and quantitative measurement of herpesvirus recovered from the lesions. It was suggested that the lack of clinical activity, in contrast to the marked activity against experimental infections in laboratory animals, resulted from the fact that high levels of herpesvirus were already present in the skin before symptoms were noted.
Utilization of Carbon Sources by
Pullularia pullulans
for the Elaboration of Extracellular Polysaccharides
Authors: Catley B. J.
Published: December 2020

The yeastlike fungus
Pullularia pullulans
utilizes simple mono- and disaccharides both in the production of cell mass and the elaboration of extracellular polysaccharide. The utilization pattern of these sugars and the effect obtained by varying the
p
H of the medium are studied, and the ability of the organism to utilize and elaborate extracellular polysaccharides from noncarbohydrate sources is explored.
Influence of Culture Media on the Antistaphylococcal Activity of Fosfomycin
Authors: Hoeprich Paul D. , Finn Pamela D.
Published: December 2020

Antagonism or double zones of inhibition (or both) resulted when
Staphylococcus aureus
was exposed to fosfomycin in Brain Heart Infusion, tryptic/papaic digest of casein/soybean, and Mueller Hinton culture media; neither occurred with a totally defined, completely synthetic medium. The extent of antagonism was quantitated by determination of the absolute minimal inhibitory concentration of fosfomycin in each medium. By using the synthetic medium and inducers, the hexose-phosphate transport system appeared to be more important than the α-glycerophosphate transport system in providing ingress of fosfomycin into staphylococci.
Polyacrylamide Gel Electrophoresis of
Corynebacterium diphtheriae:
a Possible Epidemiological Aid
Authors: Larsen Sandra A. , Bickham Susan T. , Buchanan Thomas M. , Jones Wallis L.
Published: December 2020

In this preliminary study, the use of polyacrylamide gel electrophoresis as an aid in the characterization of
Corynebacterium diphtheriae
was evaluated and a standardized method was developed. The electrophoretic patterns of 17 gravis, 14 mitis, and 2 intermedius types of
C. diphtheriae
were compared with the electrophoretic patterns of 5 Robinson and Peeney stock gravis serotype strains. Each of the 5 stock serotype strains had different electrophoretic patterns, although some common bands were present. The 17 gravis strains isolated in the United States showed patterns identical to those of the stock gravis serotype II strain. The 14 mitis strains examined produced 6 different electrophoretic patterns, irrespective of geographical location. One mitis pattern corresponded with the pattern of gravis serological type II. The two intermedius strains examined had identical electrophoretic patterns that resembled the pattern of gravis serotype IV. Polyacrylamide gel electrophoresis of
C. diphtheriae
strains may prove to be a useful epidemiologic tool in establishing the distribution and occurrence of various
C. diphtheriae
types.
Determination of Rubella Hemagglutination-Inhibiting Antibody in Whole Blood
Authors: Gupta Jiban D. , Peterson Vincent J. , Harley John D.
Published: December 2020

A technique is described for determination of rubella hemagglutination-inhibiting antibody in only 50 to 100 μliters of whole blood.
Stimulation of Mycelial Growth of
Endothia parasitica
by Heavy Metals
Authors: Englander Carol M. , Corden Malcolm E.
Published: December 2020

Of 16 metal cations tested on agar medium, only copper and iron stimulated mycelial growth of
Endothia parasitica
in relatively high concentrations. Similarly enhanced growth was produced in high (32%) glucose concentrations and also when the fungus was grown on cellophane placed over the agar surface.
E. parasitica
secreted large amounts of oxalate that precipitated primarily as calcium oxalate at the periphery of the fungal colony, causing an opaque halo in the medium. Mycelial growth was retarded greatly when calcium oxalate accumulated, but retardation was reversed by copper and iron salts that prevented accumulation of the calcium oxalate crystals.
E. parasitica
grew well on media containing copper oxalate and copper-calcium oxalate but grew poorly with calcium oxalate as the carbon source and was inhibited by sodium oxalate in the medium. The specificity by which only copper and iron salts stimulated mycelial growth suggested that the metal and oxalate ions interact to form specific oxalate complexes that reverse the inhibition of simple oxalate salts. This probably accounts for enhanced growth in the presence of otherwise toxic levels of metals and oxalate. The stimulation did not occur in liquid cultures.
Enrichment, Isolation, and Cultural Characteristics of Marine Strains of
Clostridium botulinum
Type C
Authors: Segner W. P. , Schmidt C. F. , Boltz J. K.
Published: December 2020

Terrestrial strains of
Clostridium botulinum
type C, designated 468 and 571, were used to screen various media for growth and sporulation at 30 C. Of the various formulations tested, only egg meat medium fortified with 1% additions of yeast extract, ammonium sulfate, and glucose (FEM medium) gave good growth and satisfactory sporulation. FEM medium was used to recover four marine type C isolates from inshore sediments collected along the Atlantic, the Gulf of Mexico, and the Pacific coasts of the United States. The isolation techniques involved repeated transfer of cultures showing type C toxin in FEM medium and purification by a deep tube method. The medium used for purification was beef infusion-agar supplemented with 0.14% sodium bicarbonate and 0.1%
l
-cysteine hydrochloride.
l
-Cysteine was adopted in preference to sodium thioglycolate, because some lots of the latter were definitely inhibitory for growth. The addition of bicarbonate markedly increased viable spore counts of both the marine and terrestrial strains. Various cultural and biochemical characteristics of the marine and the terrestrial strains were compared. With the exception of some variations in their fermentation patterns, both groups showed similar characteristics. Of 23 fermentable compounds tested, the terrestrial strains attacked only glucose and mannose. The marine strains fermented glucose, mannose, galactose, and ribose actively; dextrin, inositol, maltose, and melibiose were weakly fermented.
Two Compounds Inhibitory to Penicillinase-Producing Cells of
Staphylococcus aureus
Authors: Dulaney E. L.
Published: December 2020

2-[4-(4,6-Diamino-1, 2-dihydro-2, 2-dimethyl-
S
-triazin-1-yl)phenyl]-4′-(fluorosulfonyl) acetanilide ethane sulfonate salt and 4-(
p
-tert-butylbenzoyl)-3-methyl-1-phenyl-2-pyrazolin-5-one cause a shift in growing populations of plasmid-bearing
Staphylococcus aureus
cells to a population of cells lacking the plasmid.
Electron Microscope Methods for the Identification of Adenoviruses Isolated in Micro Tissue Cultures
Authors: Rosenbaum M. J. , Kory R. C. , Siegesmund K. A. , Pedersen H. J. , Sullivan E. J. , Peckinpaugh R. O.
Published: December 2020

A tissue culture micromethod is described for adenovirus isolation and preparation for presumptive identification by electron microscopy. These procedures are easier, more economical, and faster than conventional methods. The micro techniques make it more feasible to utilize direct visualization of virus in infected cells as an adjunctive diagnostic and research tool.
Semi-Micro XC Cell Assay Technique for Murine Leukemia Virus
Authors: Bass Leslie Riechers , Turner Willie
Published: December 2020

The XC cell assay employed in in vitro titration of murine leukemia viruses was modified for use as a semi-micro procedure.
Comparison of Fluorescent Antibody Induced by Rubella Virus in Vaccinee and Convalescent Individuals
Authors: Serafini Angela , Cole George C. , Brackett Robert G.
Published: December 2020

Specific rubella antibody detectable by indirect immunofluorescence developed in response to immunization with attenuated rubella vaccine, HPV-77, DK-12. Fluorescent antibody (FA) was found when vaccinee sera were reacted with antigens synthesized in three different acutely infected continuous cell lines: BHK-21, LLCMK-2, and RK-13. FA titers were high, and they correlated with antibody titers obtained by hemagglutination-inhibition tests. Levels of FA in vaccinated individuals were slightly lower than those found in persons recovered from natural rubella infections. Rubella FA persists a long time in convalescent individuals and appears to be maintained for at least 19 months in vaccinees.