bluuebunny/crossref_metadata_2025 huggingface dataset:
Correlation of
Propionibacterium acnes
Populations with the Presence of Triglycerides on Nonhuman Skin
Authors: Webster Guy F. , Ruggieri Michael R. , McGinley Kenneth J.
Published: January 2020

The skins of mice, rats, rabbits, sheep, guinea pigs, and dogs were cultured for
Propionibacterium acnes.
Only the sebaceous regions (perianal gland) of guinea pigs harbored a significant
P. acnes
population. Analysis of the lipid from this region revealed a significant percentage of triglycerides, compounds lacking in the sebum of the other animals.
Metabolic Activity of Fatty Acid-Oxidizing Bacteria and the Contribution of Acetate, Propionate, Butyrate, and CO
2
to Methanogenesis in Cattle Waste at 40 and 60°C
Authors: Mackie Roderick I. , Bryant Marvin P.
Published: January 2020

The quantitative contribution of fatty acids and CO
2
to methanogenesis was studied by using stirred, 3-liter bench-top digestors fed on a semicontinuous basis with cattle waste. The fermentations were carried out at 40 and 60°C under identical loading conditions (6 g of volatile solids per liter of reactor volume per day, 10-day retention time). In the thermophilic digestor, acetate turnover increased from a prefeeding level of 16 μM/min to a peak (49 μM/min) 1 h after feeding and then gradually decreased. Acetate turnover in the mesophilic digestor increased from 15 to 40 μM/min. Propionate turnover ranged from 2 to 5.2 and 1.5 to 4.5 μM/min in the thermophilic and mesophilic digestors, respectively. Butyrate turnover (0.7 to 1.2 μM/min) was similar in both digestors. The proportion of CH
4
produced via the methyl group of acetate varied with time after feeding and ranged from 72 to 75% in the mesophilic digestor and 75 to 86% in the thermophilic digestor. The contribution from CO
2
reduction was 24 to 29% and 19 to 27%, respectively. Propionate and butyrate turnover accounted for 20% of the total CH
4
produced. Acetate synthesis from CO
2
was greatest shortly after feeding and was higher in the thermophilic digestor (0.5 to 2.4 μM/min) than the mesophilic digestor (0.3 to 0.5 μM/min). Counts of fatty acid-degrading bacteria were related to their turnover activity.
Requirement for Calcium in Adhesion of a Fouling Diatom to Glass
Authors: Cooksey Keith E.
Published: January 2020

An assay for the adhesion of
Amphora coffeaeformis
(
Bacillariophyceae
) to glass is described. Ca
2+
and Sr
2+
promoted adhesion, but Ba
2+
and Mn
2+
were ineffective. Adhesion was inhibited by cycloheximide, carbonyl cyanide 3-chlorophenyl hydrazone, and α-isopropyl-α-[(
N
-methyl-
N
-homoveratryl)-γ-amino- propyl]-3,4,5-trimethyoxy phenyl acetonitrile (D-600), but not by 3-(3,4-dichlorophenyl)-1, 1-dimethyl urea or darkness. The assay has potential use in comparing chemical antifoulants.
Hemagglutination method for detection of freshwater cyanobacteria (blue-green algae) toxins
Authors: Carmichael W W , Bent P E
Published: January 2020

Strains of the freshwater cyanobacteria (blue-green algae) Anabaena flosaquae and Microcystis aeruginosa produced toxins that caused intermittent but repeated cases of livestock, waterfowl, and other animal deaths. They also caused illness, especially gastrointestinal, in humans. The most common group of toxins produced by these two species were peptide toxins termed microcystin, M. Aeruginosa type c, and anatoxin-c. A method was found to detect the toxins which utilizes their ability to cause agglutination of isolated blood cells from mice, rats, and humans. The method could detect the toxin in samples from natural algal blooms, laboratory cultures, and toxin extracts. The method consists of: (i) washing lyophilized cyanobacteria cells with physiological saline (0.9% NaCl), (ii) centrifuging the suspension and then mixing portions of the cell-free supernatant with equal volumes of saline-washed erythrocytes in V-shaped microtiter plates, (iii) allowing the mixture to stand for 3 to 4 h, and (iv) scoring the presence of the toxin as indicated by blood cell agglutination. Nontoxic strains, as determined by intraperitoneal mouse bioassay of cyanobacteria or green algae, did not produce an agglutination response.
Rumen Bacterial Competition in Continuous Culture:
Streptococcus bovis
Versus
Megasphaera elsdenii
Authors: Russell J. B. , Cotta M. A. , Dombrowski D. B.
Published: January 2020

Streptococcus bovis
and
Megasphaera elsdenii
were grown in continuous culture with maltose as the limiting substrate at dilution rates of 0.36, 0.22, and 0.12 h
−1
. After each steady-state turnover, the pH was decreased by adding concentrated HCl to the medium reservoir. Relative counts of the two species at each dilution rate indicated that when the pH was high (6.6 to 6.0), higher dilution rates selected for a higher ratio of
S. bovis
to
M. elsdenii.
At intermediate pH (6.0 to 5.4), higher dilution rates once again selected for greater numbers of
S. bovis
in relation to
M. elsdenii
, but the increase in
S. bovis
numbers was much less at the 0.36-h
−1
dilution rate. Decreasing the pH below 5.4 caused the ratio of
S. bovis
to
M. elsdenii
to increase greatly, and no
M. elsdenii
cells were seen below pH 5.1. The ratio of the two species could be explained by their relative affinities for maltose if pH was greater than 6.0, but the lower relative numbers of
S. bovis
in the 0.36-h
−1
, intermediate-pH (6.0 to 5.4) incubations could not. Analysis of lactate production by
S. bovis
in pure culture showed that
l
-lactate was produced only if the pH was less than 5.2 at dilution rates of 0.22 and 0.12 h
−1
and less than 6.0 at a rate of 0.36 h
−1
. The lower numbers of
S. bovis
relative to
M. elsdenii
in the incubations with a dilution rate of 0.36 h
−1
and intermediate pH thus could be explained by utilization of
l
-lactate by
M. elsdenii.
The very high numbers of
S. bovis
at pH less than 5.4 were consistent with the greater tolerance of this organism to low pH.
Bacterial Population Adherent to the Epithelium on the Roo of the Dorsal Rumen of Sheep
Authors: Dehority Burk A. , Grubb Jean A.
Published: January 2020

By anaerobic procedures, the total number of adherent bacteria was determined on tissue samples obtained from the roof of the dorsal rumen of three sheep. After four washings, 1.91 × 10
7
, 0.34 × 10
7
, and 1.23 × 10
7
bacteria per cm
2
were still attached to the rumen epithelium in sheep 1, 2, and 3, respectively. A total of 95 strains of bacteria were isolated from these three samples. Based on morphology, Gram stain, anaerobiosis, motility, and fermentation end products, they were presumptively identified as follows:
Butyrivibrio fibrisolvens
, 30 strains; atypical
Butyrivibrio
, 5 strains;
Bacteroides ruminicola
, 22 strains;
Lactobacillus
, 1 strain; and unknown
Bacteroides
species, 37 strains. For sheep 3, washing the rumen epithelium a total of 10 times reduced the adherent bacterial population by 93% (8.4 × 10
5
bacteria per cm
2
). Of 30 strains isolated from this sample, 22 were presumptively identified as
Butyrivibrio
and
Bacteroides
types. These results suggest that the epithelium on the roof of the dorsal rumen is primarily colonized by two genera of bacteria,
Butyrivibrio
and
Bacteroides
. Most
Butyrivibrio
and
Bacteroides ruminicola
strains appeared to be similar to previously isolated rumen strains. However, the unknown
Bacteroides
species differed considerably from the three species of this genus which are commonly isolated from rumen contents.
Microbial aerosols and actinomycetes in etiological considerations of mushroom workers' lungs
Authors: Kleyn J G , Johnson W M , Wetzler T F
Published: January 2020

Spent steamed compost, phase II compost, and dust emanating from spent compost during dumping of stationary-bed mushroom houses were examined bacteriologically. The total count for spent compost was 16 X 10(8) microorganisms per g. The total count for dust was 333 microorganisms per liter of air. Actinomycetes belonging to the genus Streptomyces often constituted 90% or more of isolates from dust, whereas mold spores constituted approximately 5%. Dust weight averaged 3.4 mg/liter of air and contained approximately 33% inanimate and 67% animate (microbial) particles. Spent compost and casing contained approximately 60% moisture; the average pH of compost was 6.93, and that of casing was 7.70. Ouchterlony precipitin results with antisera from workers afflicted with either farmer's or mushroom worker's lung were positive for Bacillus licheniformis, Micropolyspora faeni, Thermoactinomyces vulgaris, Aspergillus fumigatus, Humicola grisea var. thermoidea, spent compost, and phase II compost. Their usefulness in determining the etiology of this and related forms of allergic alveolitis is questioned and discussed. The relationship of dust particle size; microbial species, prevalence and antigenicity; and compost antigenicity to the etiology of mushroom worker's lung is discussed. The microbial ecology of mushroom compost and moldy hay associated with farmer's lung is compared.
Enzyme-Linked Immunosorbent Assay for Detection of Ochratoxin A
Authors: Pestka J. J. , Steinert B. W. , Chu F. S.
Published: January 2020

A simple microtest plate enzyme-linked immunosorbent assay was developed for the detection of ochratoxin A at levels as low as 25 pg per assay. The relative cross-reactivities of the antibody in this system with ochratoxin A (OA), OB, OC, and Oα were found to be 1.0, 0.14, 0.44, and 0.01, respectively.
Comparison of Growth and Toxin Production in Two Vaccine Strains of
Bacillus anthracis
Authors: Johnson Anna D. , Spero Leonard
Published: January 2020

Two vaccine strains of
Bacillus anthracis
were monitored in a 10-liter fermentor to compare growth patterns and toxin production. Under identical conditions, the Sterne strain produced all three components of anthrax toxin, whereas strain V770 produced only the protective antigen.
Possible Relationship Between Yeast Deoxyribonucleases and Deoxyribonucleic Acid Yield
Authors: El-Nakhal Hamza , Phaff H. J.
Published: January 2020

The deoxyribonucleic acid (DNA) yield and deoxyribonuclease (DNase) activity of several yeasts were correlated.
Debaryomyces castellii
and
Debaryomyces franciscae
were found to contain active DNases which carry out DNA hydrolysis, whereas the amounts of DNA as determined by extraction with Sarkosyl buffer (pH 7.8) were found to be small. On the other hand,
Candida parapsilosis, Saccharomyces carmosousae
, and
Lodderomyces elongisporus
produced no detectable DNases active at pH 7.8, and their DNA yield was correspondingly high.
L. elongisporus
was found to possess DNase only at pH 4.0.
Electron Donors Utilized by Sulfate-Reducing Bacteria in Eutrophic Lake Sediments
Authors: Smith Richard L. , Klug Michael J.
Published: January 2020

Mineralization rates of
14
C-labeled substrates were determined in the presence and absence of Na
2
MoO
4
, an inhibitor of sulfate reduction, in the profundal sediments of a shallow eutrophic lake. Sulfate reduction was inhibited by Na
2
MoO
4
at all concentrations tested (0.2 to 200 mM), whereas methane production was inhibited at Na
2
MoO
4
concentrations greater than 20 mM. Initial mineralization rates of glucose were unaffected by Na
2
MoO
4
; however, Na
2
MoO
4
decreased the mineralization rates of lactate (58%), propionate (52%), an amino acid mixture (85%), and acetate (14%). These decreases in the rates of mineralization were attributed to inhibition of sulfate reduction. Hydrogen stimulated the reduction of
35
SO
4
2−
2.5- to 2.8-fold, demonstrating potential hydrogen oxidation by sulfate-reducing bacteria. These results indicate that sulfate reducers utilize an array of substrates as electron donors and are of potential significance to the in situ mineralization of lactate, propionate, and free amino acids in these sediments.
Microcomputer-Assisted Biomass Determination of Plankton Bacteria on Scanning Electron Micrographs
Authors: Krambeck Christiane , Krambeck Hans-J�rgen , Overbeck J�rgen
Published: January 2020

Although biovolume is a better measure of biomass than is cell number, biovolumes have rarely been measured because their evaluation is extremely time-consuming. We developed a microcomputer system that assists cell size measurements on images of filtered plankton: scanning electron micrograph negatives were projected on a digitizer field, bacterial length and width were marked by a cursor, and coordinates were directly transferred to an MOS 6502 microcomputer (KIM 1). The dialogue program BABI organized and controlled the digitizer measurements in cooperation with the user, enabled corrections, and printed out results with 95% confidence limits and sample description. The time for scanning electron micrograph preparation was reduced to 15 min (quick transfer to Freon 113 during filtration and air drying). Altogether, this biovolume determination took about 2.5 h for confidence limits of �15%. Examples are given for applications of the method: (i) comparison of 10 lakes (with specific activities for glucose uptake and for heterotrophic CO
2
fixation); (ii) ranges of biomass parameters in one lake; (iii) diurnal cycles (with synchronizing effects, uptake of algal exudates, and calculation of daily growth). This method is discussed in relation to other biomass methods (epifluorescent microscopy, lipopolysaccharide technique, frequency of dividing cells) and the problem of biovolume-to-carbon conversions.
Improved method for virological analysis of food
Authors: Finance C , Villeval F , Block J C , Schwartzbrod L
Published: January 2020

A single, simple method for recovering enteroviruses from several different kinds of food, such as ground beef, fish, oysters, and mussels, has been improved. First, sample contamination technique was studied. It appears that virus adsorption occurs at food pH and varies according to the kind of food and the food-virus exchange surface. Second, virus recovery was evaluated. According to the experimental results obtained, we propose the following method. Samples are submerged in 100 ml of demineralized water adjusted to pH 9 with a conductivity of 8,000 mg of NaCl per liter. Then, viruses are concentrated by ultrafiltration or by ultracentrifugation. This method was efficient for virus recovery from the four kinds of food, even in cases of very low contamination.
Effect of soil permeability on virus removal through soil columns
Authors: Wang D S , Gerba C P , Lance J C
Published: January 2020

Laboratory experiments were performed on four different soils, using 100 cm long columns, to determine the extent of virus movement when wastewater percolated through the soils at various hydraulic flow rates. Unchlorinated secondary sewage effluent seeded with either poliovirus type 1 (strain LSc) or echovirus type 1 (isolate V239) was continuously applied to soil columns for 3 to 4 days at constant flow rates. Water samples were extracted daily from ceramic samplers at various depths of the column for the virus assay. The effectiveness of virus removal from wastewater varied greatly among the different soil types but appeared to be largely related to hydraulic flow rates. At a flow rate of 33 cm/day, Anthony sandy loam removed 99% of seeded poliovirus within the first 7 cm of the column. At flow rates of 300 cm/day and above, Rubicon sand gave the poorest removal of viruses; less than 90% of the seeded viruses were removed by passage of effluent through the entire length of the soil column. By linear regression analyses, the rate of virus removal in soil columns was found to be negatively correlated with the flow of the percolating sewage effluent. There was no significant difference in rate of removal between poliovirus and echovirus in soil columns 87 cm long. The rate of virus removal in the upper 17 cm of the soil column was found to be significantly greater than in the lower depths of the soil column. This study suggests that the flow rate of water through the soil may be the most important factor in predicting the potential of virus movement into the groundwater. Furthermore, the length of the soil column is critical in obtaining useful data to predict virus movement into groundwater.
Regulation of urease and ammonia assimilatory enzymes in Selenomonas ruminantium
Authors: Smith C J , Hespell R B , Bryant M P
Published: January 2020

Urease and glutamine synthetase activities in Selenomonas ruminantium strain D were highest in cells grown in ammonia-limited, linear-growth cultures or when certain compounds other than ammonia served as the nitrogen source and limited the growth rate in batch cultures. Glutamate dehydrogenase activity was highest during glucose (energy)-limited growth or when ammonia was not growth limiting. A positive correlation (R = 0.96) between glutamine synthetase and urease activities was observed for a variety of growth conditions, and both enzyme activities were simultaneously repressed when excess ammonia was added to ammonia-limited, linear-growth cultures. The glutamate analog methionine sulfoximine (MSX), inhibited glutamine synthetase activity in vitro, but glutamate dehydrogenase, glutamate synthase, and urease activities were not affected. The addition of MSX (0.1 to 100 mM) to cultures growing with 20 mM ammonia resulted in growth rate inhibition that was dependent upon the concentration of MSX and was overcome by glutamine addition. Urease activity in MSX-inhibited cultures was increased significantly, suggesting that ammonia was not the direct repressor of urease activity. In ammonia-limited, linear-growth cultures, MSX addition resulted in growth inhibition, a decrease in GS activity, and an increase in urease activity. These results are discussed with respect to the importance of glutamine synthetase and glutamate dehydrogenase for ammonia assimilation under different growth conditions and the relationship of these enzymes to urease.
R factors in coliform-fecal coliform sewage flora of the prairies and Northwest Territories of Canada
Authors: Bell J B , Macrae W R , Elliott G E
Published: January 2020

Coliform and fecal coliform populations found in the raw sewages and final sewage effluents of the prairie provinces and the Northwest Territories were examined for antibiotic resistance and the possession of R factors. It was determined that 8.91% of the total coliform and 10.80% of the fecal coliform populations carried R factors. The following numbers of combinations of R determinants were found: 39 in the Escherichia coli population, 6 in the Citrobacter population, 20 in the Enterobacter populations, 10 in the Klebsiella populations, and 11 in the Aeromonas populations. The maximum number of R determinants transferable simultaneously was seven; organisms with R factors containing determinants for chloramphenicol usually contained determinants for ampicillin. Of the coliform and fecal coliform populations, 2 to 4% were resistant to chloramphenicol in some provinces, and from 17 to 30% of the populations were resistant to three or more antibiotics. It was calculated that coliforms containing R factors in the raw sewage reached population levels of 1.5 X 10(7)/100 ml, and fecal coliforms containing R factors reached population levels of 8.6 X 10(5) ml. Final effluent discharges to the receiving environment contained R factor-containing coliform and fecal coliform populations of 3.1 X 10(4)/100 ml and 5.8 X 10(2)/100 ml, respectively. The incidence of bacteria containing R factors in sewage appears to be increasing with time, and their removal from sewage before discharge to the receiving environment is desirable. Consideration of data on bacteria with R factors should be made in future water quality deliberations and in discharge regulations.
Rapid chemotaxis assay using radioactively labeled bacterial cells
Authors: Wellman A M , Paerl H W
Published: January 2020

A rapid chemotaxis assay is described in which radioactively labeled cells of the assay organism are used to detect the number of cells trapped in capillaries containing attractant. The sensitivity and reproducibility of the radioactive technique is comparable to that of the dilution plating procedure of Adler (J. Adler, J. Gen. Microbiol. 17:77-91, 1973), but is faster and also permits the results of the assay to be determined on the day that the assay is run. The method could be particularly useful for environmental studies and for field experiments, since it does not rely on sterile techniques for dilution plating.
Scanning Electron Microscopy of
Cristispira
Species in Chesapeake Bay Oysters
Authors: Tall Ben D. , Nauman Robert K.
Published: January 2020

Scanning electron microscopy was employed to observe the physical interactions between
Cristispira
spp. and the crystalline style of the Chesapeake Bay oyster (
Crassostrea virginica
Gmelin 1791).
Cristispira
organisms were found associated with both the inner and outer layers of the posterior two-thirds of the style. The spirochetes possessed blunt-tipped ends, a cell diameter range of 0.6 to 0.8 μm, and distended spirochetal envelopes which followed the contour of the cells. Transmission electron microscopy showed that the distension of the envelope was probably due to the containment of numerous axial filaments. In addition, they were found to possess two distinct spiral shapes which were dependent on whether their location was inside or on the surface of the style.
Agglutination of
Erwinia stewartii
Strains with a Corn Agglutinin: Correlation with Extracellular Polysaccharide Production and Pathogenicity
Authors: Bradshaw-Rouse J. J. , Whatley M. H. , Coplin D. L. , Woods A. , Sequeira L. , Kelman A.
Published: January 2020

A bacterial agglutinin was extracted from ground corn (WI hybrid 64A × W117) seed with phosphate-buffered saline (pH 6.0) and precipitated with (NH
4
)
2
SO
4
at 70% saturation. The activities of this agglutinin against 22 strains of
Erwinia stewartii
(agent of bacterial wilt of corn) that varied in virulence were determined. Specific agglutination (agglutination titer per milligram of protein per milliliter) values were correlated negatively with virulence ratings. Strains with high specific agglutination values (15 or higher) were avirulent or weakly virulent; strains with low specific agglutination values (10 or lower) were highly virulent, with two exceptions. Avirulent strains produced butyrous colonies and released only small amounts of extracellular polysaccharide (EPS) into the medium, and the cells lacked capsules; virulent strains produced fluidal colonies and released large amounts of EPS, and the cells were capsulated. There was a strong correlation between the amount of EPS produced by each strain (as determined by increase in viscosity of the medium) and the specific agglutination value; in contrast, lipopolysaccharide compositions were similar in all strains. When cells of six fluidal strains were washed by repeatedly centrifuging and resuspending them in buffer, they were agglutinated more strongly by corn agglutinin than were unwashed cells. When avirulent cells were washed, their specific agglutination values did not increase significantly. Eight EPS-deficient mutants of
E. stewartii
, selected for resistance to the capsule-dependent bacteriophage K9, had lower virulence but higher specific agglutination than did their corresponding wild-type parents. Production of EPS appears to be essential for virulence; EPS may prevent agglutination of bacteria in the host, thus allowing their multiplication.
Gallus domestica
Yolk (Vitelline) Membrane Use for In Vitro Microbial Adherence Studies
Authors: Persi Marguerite A. , Burnham Jeffrey C.
Published: January 2020

The yolk membrane of unfertilized eggs (
Gallus domestica
) was isolated, washed, placed onto a glass holder, and utilized as an in vitro membrane model to study yeast attachment.
Effects of Phosphate in Medium on Protein Secretion in a Protein-Producing Bacterium,
Bacillus brevis
47
Authors: Tsukagoshi Norihiro , Yamada Hidehiko , Tsuboi Akio , Udaka Shigezo
Published: January 2020

Bacillus brevis
47 secreted up to 1 mg of protein per ml in a chemically defined medium, depending on phosphate concentration. The composition of exoproteins was altered quantitatively by the concentration of external phosphate. Morphologically,
B. brevis
47 showed a distinct three-layered cell wall structure and shed the outer two layers during growth.
Fermentation by the human large intestine microbial community in an in vitro semicontinuous culture system
Authors: Miller T L , Wolin M J
Published: January 2020

A semicontinuous culture of the microbial community of the human large intestine that was maintained over 81 days is described. The initial inoculum was feces, and about 200 ml of nutrient suspension was fed to 500 ml of fermentor contents once or twice daily. The nutrient suspension contained comminuted fibrous food, sodium deoxycholate, urea, acid-hydrolyzed casein, vitamins, and salts. The fermentation was monitored, and the major products were acetate, propionate, butyrate, methane, hydrogen, and carbon dioxide. The concentration of anaerobic bacteria was 2 X 10(9) per ml of culture contents and was 100 times that of fecal coliforms. When the nutrient suspension contained lettuce, celery, carrots, and unsweetened applesauce, the predominant nonsporeforming anaerobes isolated were Bacteroides species. When carrots and applesauce were omitted, the predominant nonsporeforming isolates were Fusobacterium species. On both diets, clostridia were isolated that resembled Clostridium clostridiiforme. The fermentation and bacteriological analyses indicated that the in vitro ecosystem appears to be a reasonable facsimile of the large intestine ecosystem.
Conversion of Cellulose to Methane and Carbon Dioxide by Triculture of
Acetivibrio cellulolyticus, Desulfovibrio
sp., and
Methanosarcina barkeri
Authors: Laube Victoria M. , Martin Stanley M.
Published: January 2020

The fermentation of cellulose by monocultures of
Acetivibrio cellulolyticus
and cocultures of
A. cellulolyticus-Methanosarcina barkeri, A. cellulolyticus-Desulfovibrio
sp., and
A. cellulolyticus-M. barkeri-Desulfovibrio
sp. was studied. The monoculture produced ethanol, acetate, H
2
, and CO
2
. More acetate and less ethanol was formed by the cocultures than by the monoculture. Acetate was utilized by
M. barkeri
in coculture with
A. cellulolyticus
after a lag period, whereas ethanol was metabolized by the sulfate reducer only under conditions of low H
2
partial pressure, i.e., when cocultured with
A. celluloyticus-M. barkeri
or when grown together with the methanogen. Only the three-component culture carried out the rapid conversion of cellulose to CO
2
and methane. Furthermore, this culture hydrolyzed the most cellulose—85% of that initially present. This amount was increased to 90% by increasing the population of
M. barkeri
in the triculture. Methane production was also increased, and a quicker fermentation rate was achieved.
Production of Naphthoquinone Mycotoxins and Taxonomy of
Penicillium viridicatum
Authors: Ciegler A. , Lee L. S. , Dunn J. J.
Published: January 2020

Groups I and II of
Penicillium viridicatum
were further differentiated on the basis of synthesis of two mycotoxins, xanthomegnin and viomellein. Strains previously classified as group II produced these pigments, whereas those in group I did not. These napthoquinone pigments were quantitated by thin-layer chromatography and high-pressure liquid chromatography. A new mobile phase of toluene and acetic acid effected a baseline separation of the two components. It is proposed that such biochemical distinctions be incorporated into an artificial taxonomic scheme of use to nontaxonomists.
Growth of Peptococcus and Peptostreptococcus: effect of variations of culture media on efficiency of recovery
Authors: Marshall R , Yasui V K , Prabhala R , Kaufman A K , Wallace I
Published: January 2020

Reference strains and clinical isolates of Peptococcus and Peptostreptococcus spp. were evaluated for their growth response in supplemented thioglycolate-yeast extract media. Supplements used included various combinations of hemin, menadione, sodium bicarbonate, and Tween 80. Parallel studies were done to compare the efficiency of recovery of viable cells grown in thioglycolate-based media and Wilkins-Chalgren broth and agar. In addition, the effects of age of the medium and medium storage on viable cell yields for reference strains were determined. Reference strains grown in freshly prepared thioglycolate-yeast extract medium supplemented with sodium bicarbonate produced a 10-fold greater increase in the number of viable cells recovered after 24 h of incubation than did the same organisms cultivated in Wilkins-Chalgren medium. The efficiency of recovery of organisms when either mid-logarithmic- or mid-stationary-phase cells were used to prepare standardized inocula was similar. The results suggest that thioglycolate-yeast extract medium supplemented with sodium bicarbonate is more productive than Wilkins-Chalgren medium for the cultivation of anaerobic gram-positive cocci and may represent a suitable alternative for antimicrobial susceptibility testing of these organisms.
Coliform inhibition by bacteriocin-like substances in drinking water distribution systems
Authors: Means E G , Olson B H
Published: January 2020

Bacterial isolates from an unchlorinated potable groundwater system and a chlorinated surface water system were screened by an agar overlay method for the ability to produce bacteriocin-like substances (BLS) inhibitory to the growth of Escherichia coli, Klebsiella sp., and Enterobacter aerogenes. The production of coliform-specific BLS by noncoliform bacteria varied with the site and date of isolation as well as the genus of the producer strain. A total of 448 bacterial isolates were screened from the chlorinated system, and 22.1% produced BLS specific for at least one of the three coliforms. In the unchlorinated system, 7.9% (n = 696) possessed this ability. Flavobacterium/Moraxella comprised 57.1% of all bacteria (from both systems) producing BLS. The possibility that BLS interfere with coliform detection in standard bacteriological water quality tests is discussed.
Influence of Indigenous Microbiota on Amount of Protein and Activities of Alkaline Phosphatase and Disaccharidases in Extracts of Intestinal Mucosa in Mice
Authors: Whitt Dixie D. , Savage Dwayne C.
Published: January 2020

The protein content and the activities of alkaline phosphatase, maltase, and sucrase were measured at 0800, 1000, 1200, 1400, and 1600 in saline extracts of the proximal small bowels of germfree and of ex-germfree mice colonized with an indigenous microbiota. In extracts prepared from germfree mice, the total activities of all of the enzymes were relatively constant throughout the sampling period. Likewise, the total activity of alkaline phosphatase in extracts prepared from associated mice varied little as a function of time. By contrast, the total activities of maltase and sucrase in the extracts from these latter animals varied significantly from sample to sample. The total activity levels in extracts from germfree mice were approximately twofold greater than the levels in extracts from associated mice. The specific activities of alkaline phosphatase and sucrase did not vary from sample to sample in extracts prepared from either type of mouse. In contrast, the specific activity of maltase in extracts prepared from both germfree and associated mice differed significantly from sample to sample. The specific activities of all three enzymes were greater in extracts from germfree animals than in those from associated animals. The protein content of extracts prepared from germfree mice also was greater than that of extracts prepared from associated animals at every sampling time. The amount of protein extractable from the mucosa of the small bowels of the former animals varied significantly at different sampling times during the day, whereas the amount of protein extractable from the tracts of associated animals remained relatively constant throughout the day. The indigenous microbiota apparently stabilizes in some way the amount of protein extractable from the mucosa of the mouse small bowel.
Brevianamides A and B Are Formed Only After Conidiation Has Begun in Solid Cultures of
Penicillium brevicompactum
Authors: Bird B. A. , Remaley A. T. , Campbell I. M.
Published: January 2020

In cultures of
Penicillium brevicompactum
grown on Czapek-Dox agar or on circles of dialysis membrane placed on Czapek-Dox agar, brevianamides A and B first appeared after conidiation had begun. The presence of these brevianamides imparted a yellow-green fluorescence to the penicilli and to the upper section of the conidiophores of actively conidiating cultures. Experiments with replacement cultures indicated that medium nutrient levels had little direct effect on brevianamide production. If
P. brevicompactum
was grown between two circles of dialysis membrane, no aerial hyphae were formed, and brevianamide production was not observed. Three brevianamide-minus mutants of
P. brevicompactum
were isolated.
Inactivation of
Giardia lamblia
Cysts by Ultraviolet Irradiation
Authors: Rice Eugene W. , Hoff John C.
Published: January 2020

Giardia lamblia
cysts were found to be resistant to high doses of germicidal ultraviolet radiation.
PH and growth of Torulopsis pintolopesii in media containing various sugars as carbon and energy sources
Authors: Huelsmann C , Savage D C
Published: January 2020

Growth within the pH range 2 to 8 of a strain of the yeast Torulopsis pintolopesii was tested in media containing various sugars as carbon and energy sources. Of the sugars tested, only D-glucose, D-fructose, and D-mannose supported growth of the yeast. In media containing those sugars, the organism grew over the entire pH range tested.
Hydroxamic Acid from
Histoplasma capsulatum
That Displays Growth Factor Activity
Authors: Burt Wayne R. , Underwood Anthony L. , Appleton Georgia L.
Published: January 2020

Growth factor(s) present in a spent liquid medium after culture of the yeast form of
Histoplasma capsulatum
enhanced both yeast and mycelial growth of nine isolates tested. Hydroxamic acid extracted from the culture fluid displayed growth factor activity.
Nitrate Accumulation in Aerobic Hypolimnia: Relative Importance of Benthic and Planktonic Nitrifiers in an Oligotrophic Lake
Authors: Vincent Warwick F. , Downes Malcolm T.
Published: January 2020

Both nitrate and nitrous oxide accumulate in the hypolimnion of the oligotrophic Lake Taupo, New Zealand, throughout stratification. The two forms of oxidized nitrogen increase in concentration with increasing depth toward the sediments, where the dissolved concentrations of reduced nitrogen are two orders of magnitude higher than concentrations in the overlying water. Nitrification rates were measured by dark [
14
C]CO
2
assays with and without the inhibitor nitrapyrin. The fastest rates were recorded for planktonic nitrifiers in the epilimnion and benthic species in the surficial 2.5 mm of the sediments. Nitrifying bacteria were least active in the deep hypolimnion. Deepwater accumulation of NO
3
−
in Lake Taupo must therefore be a product of benthic rather than planktonic nitrification.
Endogenous radiolabeling of enterotoxin from Clostridium perfringens type A on a defined medium
Authors: Granum P E , Skjelkvåle R
Published: January 2020

Four enterotoxin-positive strains of Clostridium perfringens were tested for sporulation and enterotoxin production on defined media. The medium described by Sacks and Thompson (Appl. Environ. Microbiol. 35:405-409, 1978) gave the highest enterotoxin production and was selected for the production of endogenously labeled enterotoxin. The specific radioactivity of the enterotoxin was 16,000 dpm/microgram when the tritiated amino acids were added to the growth medium just before the inoculum. Addition of the radioactive amino acids during the growth period gave consistently lower specific radioactivity. When the enterotoxin was produced on the medium described by Duncan and Strong (Appl. Microbiol. 16:82-89, 1968), the highest specific radioactivity of the enterotoxin was found when the radioactive amino acids were added to the growth medium 4 h after inoculation. In this case, the specific activity of the enterotoxin was 10,000 dpm/microgram.
Improved Isolation of Salmonellae from Naturally Contaminated Meat Products by Using Rappaport-Vassiliadis Enrichment Broth
Authors: Vassiliadis Peter , Kalapothaki Victoria , Trichopoulos Dimitrios , Mavrommatti Christofili , Serie Charles
Published: January 2020

A total of 454 specimens of meat products were examined for salmonellae by using five procedures of enrichment. The use of a selective motility medium, inoculated from enrichment in Muller-Kauffmann broth, resulted in an increase in the number of positive specimens. However, simple enrichment in Rappaport-Vassiliadis broth, after preenrichment, was more sensitive and specific for recovering salmonellae than the selective motility medium-Muller-Kauffmann broth method.
Isolation of Alkaline and Neutral Proteases from
Aspergillus flavus
var.
columnaris
, a Soy Sauce Koji Mold
Authors: Impoolsup Attawut , Bhumiratana Amaret , Flegel Timothy W.
Published: January 2020

Two different extracellular proteases, protease I (P-I), an alkaline protease, and protease II (P-II) a neutral protease, from
Aspergillus flavus
var.
columnaris
were partially purified by using (NH
4
)
2
SO
4
precipitation, diethylaminoethyl-Sephadex A-50 chromatography, carboxymethylcellulose CM-52 chromatography, and Sephadex G-100 gel filtration. The degree of purity was followed using polyacrylamide gel electrophoresis. The activity of P-I was completely inhibited by 0.1 mM phenylmethylsulfonyl fluoride, and that of P-II was completely inhibited by 1 mM ethylenediaminetetraacetate. By using these inhibitors with extracts of wheat bran koji, the proportions of total activity that could be assigned to P-I and P-II were 80 and 20%, respectively. This compared favorably with activities estimated by using polyacrylamide gel electrophoresis slices (82 and 18%, respectively). Extracts from factory-run soybean koji gave comparable results. Both enzymes demonstrated maximum activity at 50 to 55°C and only small changes in activity between pH 6 and 11. For P-I, activity was somewhat higher from pH 8.0 to 11.0, whereas for P-II it was somewhat higher from pH 6 to 9. In the presence of 18% NaCl, the activities of both P-I and P-II dropped by approximately 90 and 85%, respectively. P-I was inferred to possess aminopeptidase activity since it could hydrolyze
l
-leucyl-
p
-nitroanilide hydrochloride. P-II was devoid of such activity. The ramifications of the results for factory-produced soy sauce koji are discussed.
Inorganic Sulfur Oxidation by
Aureobasidium pullulans
Authors: Killham K. , Lindley N. D. , Wainwright M.
Published: January 2020

Aureobasidium pullulans
(de Bary) Arnaud isolated from the phylloplane of sycamore exposed to heavy atmospheric pollution oxidized S
0
to S
2
O
3
2−
, S
4
O
6
2−
, and SO
4
2−
in vitro. The intermediates S
2
O
3
2−
and S
4
O
6
2−
were also oxidized to SO
4
2−
. Cell-free extracts of
A. pullulans
also oxidized reduced forms of S, the oxidation increasing linearly with increasing protein concentration, showing that the process is enzymatic. The possible role of fungi in S oxidation in soils is discussed.
Role of
Megasphaera elsdenii
in the Fermentation of
dl
-[2-
13
C]lactate in the Rumen of Dairy Cattle
Authors: Counotte G. H. M. , Prins R. A. , Janssen R. H. A. M. , deBie M. J. A.
Published: January 2020

Since
Megasphaera elsdenii
ferments a variable part of
dl
-lactate to butyrate, measurement of the percentage of
dl
-lactate fermented to propionate via the acrylate pathway in rumen contents will underestimate the participation of
M. elsdenii
in the
dl
-lactate fermentation. The percentage of
dl
-[2-
13
C]lactate fermented via the acrylate pathway and the percentage of
dl
-lactate fermented to butyrate can be measured with
13
C-FT (Fourier transform)-nuclear magnetic resonance. On the average, the contribution of
M. elsdenii
to
dl
-lactate fermentation in the rumen of dairy cattle was found to be 74% (standard deviation, 13%), but differed with animal or diet. After feeding a cow readily fermentable carbohydrates, the contribution of
M. elsdenii
to the fermentation of
dl
-lactate increased as a consequence of catabolite repression in other
dl
-lactate-fermenting bacteria.
Effect of Plating Medium on Heat Activation Requirement of
Clostridium botulinum
Spores
Authors: Montville Thomas J.
Published: January 2020

Clostridium botulinum
62A and ATCC 25763 spores required heat activation for maximum colony formation when plated on reinforced clostridial agar (BBL Microbiology Systems) but not when plated on botulinum assay medium. Spores from strains B-aphis and 53B did not exhibit heat activation when plated on either medium.
Identification of a Growth Stimulant for
Lactobacillus sanfrancisco
Authors: Berg R. W. , Sandine W. E. , Anderson A. W.
Published: January 2020

A compound required for the luxuriant growth of
Lactobacillus sanfrancisco
in laboratory media was isolated from a freshly prepared yeast extract, purified, and characterized. The stimulant was identified as a small peptide with a molecular weight of approximately 1,065, containing aspartic acid, cysteine, glutamic acid, glycine, and lysine.
Biodegradation of Hexahydro-1,3,5-Trinitro-1,3,5-Triazine
Authors: McCormick N. G. , Cornell J. H. , Kaplan A. M.
Published: January 2020

Biodegradation of the explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) occurs under anaerobic conditions, yielding a number of products, including: hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine, hexahydro-1,3-dinitroso-5-nitro-1,3,5-triazine, hexahydro-1,3,5-trinitroso-1,3,5-triazine, hydrazine, 1,1-dimethyl-hydrazine, 1,2-dimethylhydrazine, formaldehyde, and methanol. A scheme for the biodegradation of RDX is proposed which proceeds via successive reduction of the nitro groups to a point where destabilization and fragmentation of the ring occurs. The noncyclic degradation products arise via subsequent reduction and rearrangement reactions of the fragments. The scheme suggests the presence of several additional compounds, not yet identified. Several of the products are mutagenic or carcinogenic or both. Anaerobic treatment of RDX wastewaters, which also contain high nitrate levels, would permit the denitrification to occur, with concurrent degradation of RDX ultimately to a mixture of hydrazines and methanol. The feasibility of using an aerobic mode in the further degradation of these products is discussed.
Microbiological Degradation of Organic Components in Oil Shale Retort Water: Organic Acids
Authors: Rogers J. E. , Riley R. G. , Li S. W. , Mann D. C. , Wildung R. E.
Published: January 2020

The losses of benzoic acid and a homologous series of both mono- and dibasic aliphatic acids in oil shale retort water were monitored with time (21 days) in liquid culture (4% retort water, vol/vol) inoculated with soil. The organic acids constituted approximately 12% of the dissolved organic carbon in retort water, which served as the sole source of carbon and energy in these studies. The levels of the acids in solution were reduced by 80 to 90% within 9 days of incubation. From mass balance calculations, the decrease in dissolved organic carbon with time of incubation was equal to the formation of CO
2
and bacterial cell carbon. The decrease in the level of the acid components, either from degradation to CO
2
or incorporation into bacteria, would account for ∼70% of the loss in dissolved organic carbon within the first 9 days of incubation and would account for ∼50% of the loss over the entire 21-day incubation period.
Bacterial Culture Preservation in Frozen and Dry-Film Methylcellulose
Authors: Suslow Trevor V. , Schroth Milton N.
Published: January 2020

Forty-seven of 61 bacterial cultures, including strains of
Pseudomonas, Xanthomonas, Erwinia, Agrobacterium, Corynebacterium, Serratia, Klebsiella
, and
Escherichia
, remained viable after storage in frozen methylcellulose or in dried methylcellulose for up to 38 months. Pathogenicity remained intact for those strains tested. Bacteria were grown on a solid medium and then removed and placed in 1.0% methylcellulose (cellulose methyl ether) to make a final suspension of 10
8
colony-forming units (CFU) per ml. For storage in dried form, the bacteria-methylcellulose suspension was placed in a petri dish and dried in a forced-air incubator. After 24 h of storage at 25°C, viable populations of 10
5
CFU/mg (equivalent to 10
6
CFU/ml) were recovered. Populations of 10
2
to 10
4
CFU/mg were recovered after storage of up to 38 months. Similar results were obtained in frozen methylcellulose. Survival was greatly enhanced when the growth medium for the bacteria was potato dextrose peptone rather than nutrient agar, yeast dextrose calcium carbonate peptone, or King's medium B. Addition of 0.1 M MgSO
4
to the methylcellulose suspension and to the resuspending liquid also increased survival and recovery from storage for some strains. Methylcellulose storage should be a simple, inexpensive, and reliable method of maintaining cultures for short or long periods of time.
Transformation of bile acids by Eubacterium lentum
Authors: Hirano S , Masuda N
Published: January 2020

A group of fecal isolates identified as Eubacterium lentum elaborated 3 alpha-, 7 alpha-, and 12 alpha-dehydrogenases and also an epimerizing enzyme(s) for the 3 alpha-hydroxy group. The activities of the enzymes, however, were variably manifested according to the kind of bile acid substrate and the oxygen tension under which the reaction occurred.
A-1 medium: alternative technique for fecal coliform organism enumeration in chlorinated wastewaters
Authors: Standridge J H , Delfino J J
Published: January 2020

A 24-h most-probable-number technique using A-1 medium for detecting fecal coliforms in chlorinated wastewaters was evaluated. The A-1 medium technique, using 3 h of preincubation at 35 degrees C, gave results statistically equivalent to those obtained with the American Public Health Association Standard Methods two-step most-probable-number technique.
Enhancement of the Microbial Dehalogenation of a Model Chlorinated Compound
Authors: Jacobson Stuart N. , Alexander Martin
Published: January 2020

A number of chlorinated aromatic and aliphatic compounds were dehalogenated when incubated with sewage. Preincubating the sewage with nonchlorinated organic substrates enhanced the subsequent dehalogenation of the chlorinated chemicals. Dehalogenation of 4-chloro-3,5-dinitrobenzoic acid (CDBA) in lake water occurred as a result of microbial growth both in the light in the absence of added nutrients and in the dark in the presence of acetate. No organism able to use CDBA as a carbon source was isolated. Axenic bacterial cultures and a nonaxenic
Chlamydomonas
culture released chloride from CDBA. The metabolism of CDBA by the latter culture, a process that was inhibited by 3-(3,4-dichlorophenyl)-1,1-dimethylurea, yielded a product that was identified as α-hydroxymuconic semialdehyde. This product of an apparent cometabolic transformation was mineralized by a strain of
Streptomyces
, thus suggesting that certain cometabolic products may not accumulate because they are carbon sources for other species.
Specific Adhesion of Bacteria to Heterocysts of
Anabaena
spp. and Its Ecological Significance
Authors: Lupton F. S. , Marshall K. C.
Published: January 2020

Two bacterial isolates,
Pseudomonas
sp. SL10 and
Zoogloea
sp. SL20, attach to heterocysts of
Anabaena
spp. with a high degree of selectivity, and this attachment can be expressed quantitatively in terms of adsorption isotherms. Adhesion of
Pseudomonas
sp. SL10 was restricted to a monolayer and exhibited a type I (Langmuir) isotherm, whereas adhesion of
Zoogloea
sp. SL20 involved multilayer attachment and exhibited a type II isotherm. The degree of adhesion by the bacteria to heterocysts of different
Anabaena
species may reflect the distribution and abundance of binding sites on the surface of different heterocysts. Both
Pseudomonas
sp. SL10 and
Zoogloea
sp SL20 promoted higher rates of acetylene reduction by
Anabaena
spp. under oxygenated culture conditions when compared with a cyanobacterial control. At ambient oxygen levels, however, only
Zoogloea
sp. SL20 stimulated acetylene reduction by
Anabaena
spp.