bluuebunny/crossref_metadata_2025 huggingface dataset:
Production of Ethanol from
d
-Xylose by Using
d
-Xylose Isomerase and Yeasts
Authors: Gong Cheng-Shung , Chen Li-Fu , Flickinger Michael C. , Chiang Lin-Chang , Tsao George T.
Published: January 2020

d
-Xylulose, an intermediate of
d
-xylose catabolism, was observed to be fermentable to ethanol and carbon dioxide in a yield of greater than 80% by yeasts (including industrial bakers' yeast) under fermentative conditions. This conversion appears to be carried out by many yeasts known for
d
-glucose fermentation. In some yeasts, xylitol, in addition to ethanol, was produced from
d
-xylulose. Fermenting yeasts are also able to produce ethanol from
d
-xylose when
d
-xylose isomerizing enzyme is present. The results indicate that ethanol could be produced from
d
-xylose in a yield of greater than 80% by a two-step process. First,
d
-xylose is converted to
d
-xylulose by xylose isomerase.
d
-Xylulose is then fermented to ethanol by yeasts.
Carboxymethyl cellulase and cellobiase production by Clostridium acetobutylicum in an industrial fermentation medium
Authors: Allcock E R , Woods D R
Published: January 2020

The production of a carboxymethyl cellulase and a cellobiase by Clostridium acetobutylicum was demonstrated. In liquid medium the carboxymethyl cellulase was induced by molasses, and it was not repressed by glucose. Optimum carboxymethyl cellulase activity occurred at pH 4.6 and 37 degrees C.
Occurrence of Yersinia enterocolitica in wild animals
Authors: Kaneko K , Hashimoto N
Published: January 2020

Yersinia species were isolated from 16 of 495 small wild animals and from 1 of 38 foxes. The animals were trapped in seven regions of Hokkaido, Japan. Of the 17 strains isolated, 9 were Yersinia enterocolitica O6; 2 were Y. enterocolitica O5A; 1 was Y. enterocolitica, O4; 1 was Y. enterocolitica O9; 1 was Yersinia pseudotuberculosis IVB; and 3 were sucrose-negative strains. Yersinia pestis was not isolated. The O6 organism was most prevalent in large red-back mice (Clethrionomys rufocanus bedfordiae) and showed significant differences in its mode of distribution according to region. Incidence of the O6 organism in the ileum of the animal was threefold that in the cecum, and the organism was recovered at approximately 10(5) cells per g of cecal contents per c. rufocanus bedfordiae animal.
Effects of activated carbon and bacteriostatic filters on microbiological quality of drinking water
Authors: Tobin R S , Smith D K , Lindsay J A
Published: January 2020

Three activated carbon filters for point-of-use water treatment were tested in laboratory and field studies for chemical removal and microbiological effects on water. All removed free available chlorine in municipally treated water to below the limit of detection, but removed only about 50 to 70% of the total available chlorine and 4 to 33% of the total organic carbon. Standard plate count bacteria in the effluent increased steadily with time for 3 weeks and remained elevated over the 8-week period of the study. Total coliform bacteria were found to persist and proliferate on the filters for several days after transient contamination of the influent water. Silver-containing activated carbon filters suppressed total coliform but not total bacterial growth. Pseudomonas aeruginosa was recovered from the effluents of all filters at some time during the tests.
Inactivation of poliovirus and other enteroviruses by solutions of sodium fluoride at low pH
Authors: Eubanks R D , Farrah S R
Published: January 2020

Solutions of sodium fluoride at pH 3 to 4 inactivated enteroviruses, whereas other sodium salts had little or no effect on virus infectivity. Solutions of potassium fluoride also inactivated viruses under similar conditions. Light, temperature, and the presence of organic compounds such as detergents and fecal matter did not affect inactivation of virus by 0.4 M solutions of sodium fluoride at pH 3. to 4. Decreasing the sodium fluoride concentration below 0.04 M or raising the pH above 4 reduced the viricidal properties of the solutions. Virus adsorbed to membrane filters and sludge flocs could not be recovered after treatment of solids-associated virus with solutions of sodium fluoride.
Influence of Nitrogen Source, Thiamine, and Light on Biosynthesis of Abscisic Acid by
Cercospora rosicola
Passerini
Authors: Norman Shirley M. , Maier Vincent P. , Echols Linda C.
Published: January 2020

Abscisic acid production by
Cercospora rosicola
Passerini in liquid shake culture was measured with different amino acids in combination and singly as nitrogen sources and with different amounts of thiamine in the media. Production of abscisic acid was highest with aspartic acid-glutamic acid and aspartic acid-glutamic acid-serine mixtures as nitrogen sources. Single amino acids that supported the highest production of abscisic acid were asparagine and monosodium glutamate. Thiamine was important for abscisic acid production. Leucine inhibited abscisic acid production.
C. rosicola
produced abscisic acid in the dark, but production more than doubled in the presence of light.
Polyguaiacol: a Useful Model Polymer for Lignin Biodegradation Research
Authors: Crawford R. L. , Robinson L. E. , Foster R. D.
Published: January 2020

A polymer of ring-labeled [
14
C]
o
-methoxyphenol ([
14
C]guaiacol) was prepared by peroxidase-H
2
O
2
-catalyzed oxidation of the
14
C-labeled monomeric compound. The ring-labeled [
14
C]polyguaiacol contained 67.71% carbon, 5.09% hydrogen, 27.49% oxygen, 25.44% methoxyl, and 8.60% phenolic hydroxyl. The polymer had an average molecular weight of between 5,000 and 15,000, as determined by gel chromatography. A schematic representation of the polymer, similar to previously published structures of polyguaiacols, was devised to meet these and other analytical parameters. The polymer is primarily composed of
o-o
and
p-p
-linked guaiacol moieties, with an occasional
o-p
-biphenyl link and some
p
-diphenoquinone structures. An approximate molecular formula is [C
49
O
14
H
31
]

n

, where
n
5.8. Its C
6
formula is C
6
H
2.3
O
0.3
carbonyl
(OH)
0.7
(OCH
3
)
1.0
. Polyguaiacol has many of the characteristics of a synthetic lignin. It is easier and less expensive to prepare than standard synthetic lignins (dehydrogenation polymers of coniferyl alcohol). It is degraded ([
14
C]polyguaiacol →
14
CO
2
) by the lignolytic system of the white-rot fungus
Phanaerochaete chrysosporium.
It is suggested that [
14
C]polyguaiacol may be of value as a substrate for lignin biodegradation research.
Response of bacteria in wastewater sludge to moisture loss by evaporation and effect of moisture content on bacterial inactivation by ionizing radiation
Authors: Ward R L , Yeager J G , Ashley C S
Published: January 2020

Two studies were carried out to determine the influence of moisture content of the survival of bacteria in raw wastewater sludge. The first study involved the effect of water loss by evaporation on the bacterial population. The second used these dewatered samples to measure the effects of moisture content on the inactivation of bacteria sludge by ionizing radiation. Both studies involved survival measurements of six representative fecally associated bacteria grown separately in sterilized sludge as well as survival data on bacteria indigenous to sludge. Growth of bacteria was stimulated in sludge during the initial phase of moisture removal by evaporation, but the reduction of moisture content below about 50% by weight caused a proportional decrease in bacterial numbers. In comparison with the original sludge, this decrease reached about one-half to one order of magnitude in all dried samples except those containing Proteus mirabilis, which decreased about four orders of magnitude. The rates of inactivation of bacteria by ionizing radiation in sludge were usually modified to some degrees by variations in moisture content. Most bacteria were found to be somewhat protected from ionizing radiation at reduced moisture levels. The largest effect was found with Salmonella typhimurium, whose radiation resistance approximately doubled in dried sludge. However, no excessively large D10 values were found for any bacterial species tested.
Atypical Escherichia coli in streams
Authors: Rychert R C , Stephenson G R
Published: January 2020

In the examination of stream waters for fecal coliforms, pale yellow colonies regularly appeared on m-FC broth base medium plates. The yellow colonies may comprise 70% more of the colonies of an m-FC plate. More than 80% of these colonies were identified as Escherichia coli by the API 20E identification system and by serotyping. The atypical yellow E. coli strains were not environmentally stressed E. coli since the atypical colonies continued to be yellow on m-FC medium after growth in a nonselective medium. However, 50% of the atypical E. coli strains were o-nitrophenyl-beta-D-galactopyranoside positive, and 20% produced gas in EC medium at 44.5 degrees C. Failure to consider these atypical E. coli strain in water quality analyses could lead to a significant error in the estimation of water quality in some instances.
Factors Affecting Oxidation of Thiosalts by Thiobacilli
Authors: Silver M. , Dinardo O.
Published: January 2020

The effects of temperature, initial pH, and the concentrations of ammonium, phosphate, and heavy metals on the oxidation of thiosalts by an authentic strain of
Thiobacillus thiooxidans
(ATCC 8085) and by a mixed culture isolated from a base metal-processing mill effluent pond were studied. The optimum temperature was 30°C and the optimum initial pH was 3.75 for both cultures using thiosulfate and for the mixed culture using tetrathionate.
T. thiooxidans
ATCC 8085 did not oxidize tetrathionate. For a thiosalt concentration of 2,000 ppm (2,000 mg/liter), maximal rates of destruction occurred at concentrations of ammonium ion above 2 mg/liter and in the presence of 1 mg of phosphate per liter. Under optimal conditions, the rate of thiosulfate oxidation by the pure culture was 55 ± 3 mg/liter per h; the mixed culture oxidized thiosulfate at the rate of 40 ± 1 mg/liter per h and tetrathionate at the rate of 50 ± 2 mg/liter per h. Metal ions caused normal inhibition kinetics in the oxidation of thiosulfate by
T. thiooxidans
ATCC 8085.

K
i

values were calculated for cadmium (16 mg/liter), copper (0.46 mg/liter), lead (2 mg/liter), silver (3.1 mg/liter), and zinc (33 mg/liter). Only a slight additive effect was apparent in the presence of all of these metal ions. The mixed culture of thiosalt-oxidizing bacteria was less sensitive to heavy metal inhibition; the order of inhibition of thiosulfate oxidation was Cd < Zn < Pb < Ag < Cu, and that of tetrathionate oxidation was Zn < Cd < Pb < Ag < Cu.
Isolation of
Arthrobacter
Bacteriophage from Soil
Authors: Germida James J. , Casida L. E.
Published: January 2020

Soil was percolated with water and various nutrient solutions, and then the percolates were analyzed for bacteriophages which produced plaques on various
Arthrobacter
strains. The water percolates did not contain detectable phage. In contrast, phages for
A. globiformis
strains ATCC 8010 and 4336, and for several recent
Arthrobacter
species soil isolates, were easily detected in nutrient broth, soil extract, and cation-complete medium percolates. These percolates did not contain phage that produced plaques on
A. oxydans
and a recent
Arthrobacter
species soil isolate. Percolation with a selective nicotine-salts solution was required for demonstrating phage for these bacteria. None of the percolates contained phage for five additional named
Arthrobacter
species. In addition, phages were not detected for
A. crystallopoietes
in a 2-hydroxypyridine percolate of soil. Based on their lytic spectra, the phage isolates from this soil were relatively host specific.
Effect of Nitrogen Source on End Products of Naphthalene Degradation
Authors: Aranha Hazel G. , Brown Lewis R.
Published: January 2020

Soil cultures, enrichment cultures, and pure culture isolates produced substantial quantities of salicylic acid from naphthalene in a mineral salts medium containing NH
4
Cl as the nitrogen source. However, when KNO
3
was substituted for NH
4
Cl, these same cultures failed to accumulate detectable quantities of salicylic acid but did turn the medium yellow. When an isolate identified as a
Pseudomonas
species was used, viable cell numbers were much greater in the medium containing KNO
3
, but up to 94% of the naphthalene was utilized in both media. After 48 h of incubation in a 0.1% naphthalene-mineral salts medium, the cultures containing NH
4
Cl showed irregular clumped cells, a pH of 4.7, 42 μg of salicylic acid per ml, and the production of 4.4 ml of CO
2
. Under the same conditions, the cultures in the medium containing KNO
3
showed uniform cellular morphology, a pH of 7.3, no salicylic acid, the production of 29.7 ml of CO
2
, and a distinct yellow coloration of the medium. The differences between nitrogen sources could not be accounted for by pH alone since results obtained using buffered media were similar. Growth with NH
4
NO
3
displayed a pattern similar to that obtained when NH
4
Cl was used. The yellow coloration in the medium containing KNO
3
was apparently due to more than one compound, none of which were 1,2-naphthoquinone or acidic in nature, as suggested by other investigators. Further attempts to identify the yellow compounds by high-pressure liquid chromatography, infrared analysis, and gas chromatography-mass spectrometry have been unsuccessful thus far.
Antibiotic-resistant bacteria in drinking water
Authors: Armstrong J L , Shigeno D S , Calomiris J J , Seidler R J
Published: January 2020

We analyzed drinking water from seven communities for multiply antibiotic-resistant (MAR) bacteria (bacteria resistant to two or more antibiotics) and screened the MAR bacterial isolates obtained against five antibiotics by replica plating. Overall, 33.9% of 2,653 standard plate count bacteria from treated drinking waters were MAR. Two different raw water supplies for two communities carried MAR standard plate count bacteria at frequencies of 20.4 and 18.6%, whereas 36.7 and 67.8% of the standard plate count populations from sites within the respective distribution systems were MAR. Isolate identification revealed that MAR gram-positive cocci (Staphylococcus) and MAR gram-negative, nonfermentative rods (Pseudomonas, Alcaligenes, Moraxella-like group M, and Acinetobacter) were more common in drinking waters than in untreated source waters. Site-to-site variations in generic types and differences in the incidences of MAR organisms indicated that shedding of MAR bacteria living in pipelines may have contributed to the MAR populations in tap water. We conclude that the treatment of raw water and its subsequent distribution select for standard plate count bacteria exhibiting the MAR phenotype.
Characterization of a Nuclear Polyhedrosis Virus Isolated from Diseased
Gonometa podocarpi
(Lepidoptera:Lasiocampidae)
Authors: Moore Norman F. , Armstrong Terry , Green Bernadette , Brown David , Hibbin Jill , Kelly David C. , Tinsley Thomas W. , Aloo Theresa C.
Published: January 2020

Gonometa podocarpi
is an important pest of several species of pine in East Africa, and large numbers of trees in plantations in Kenya were partially or completely defoliated by the larval stage of this insect. After the infestation in the Mt. Elgon region, large numbers of dead and moribund larvae were found on the ground. Examination of extracts of these larvae demonstrated the presence of an occluded virus. Electron microscopy of purified sectioned polyhedra demonstrated the presence of virus particles containing from 1 to 12 nucleocapsids. Purification of virus particles from polyhedra was accomplished by using alkali solubilization and sucrose gradient centrifugation. Virus particles contained 15 proteins as determined by polyacrylamide gel electrophoresis. Detergent solubilization of the virus particles released polyhedra containing one major structural protein. Electron microscopy of purified virus particles and nucleocapsids demonstrated them to be similar in structure to previously recorded nuclear polyhedrosis viruses. The viral deoxyribonucleic acid was extracted and spread for electron microscopy and was determined to have a size of approximately 80 × 10
6
daltons.
Toxicity of
Bacillus thuringiensis
Spo
−
Cr
+
Mutants for the European Corn Borer
Ostrinia nubilalis
Authors: Johnson Donovan E. , Freedman Bernard
Published: January 2020

Inclusion bodies isolated from Spo
−
Cr
+
mutants of
Bacillus thuringiensis
were toxic for larvae of the European corn borer. Probit analysis revealed comparable toxicity between wild-type crystals (isolated from
B. thuringiensis
subsp.
kurstaki
) and crystals produced from two spore-free mutants of the same subspecies. Death of the larvae was due to starvation, presumably through δ-endotoxin-induced gut paralysis. Inclusion bodies pretreated with α-chymotrypsinogen were equally as toxic as native crystals for the insect larvae.
Enzymatic Basis for Overproduction of Tryptophan and Its Metabolites in
Hansenula polymorpha
Mutants
Authors: Denenu Emmanuel O. , Demain Arnold L.
Published: January 2020

3-Deoxy-
d
-arabinoheptulosonate 7-phosphate (DAHP) synthetase and anthranilate synthetase are key regulatory enzymes in the aromatic amino acid biosynthetic pathway. The DAHP synthetase activity of
Hansenula polymorpha
was subject to additive feedback inhibition by phenylalanine and tyrosine but not by tryptophan. The synthesis of DAHP synthetase in this yeast was not repressed by exogenous aromatic amino acids, singly or in combinations. The activity of anthranilate synthetase was sensitive to feedback inhibition by tryptophan, but exogenous tryptophan did not repress the synthesis of this enzyme. Nevertheless, internal repression of anthranilate synthetase probably exists, since the content of this enzyme in
H. polymorpha
strain 3-136 was double that in the wild-type and less sensitive 5-fluorotryptophan-resistant strains. The biochemical mechanism for the overproduction of indoles by the 5-fluorotryptophan-resistant mutants was due primarily to a partial desensitization of the anthranilate synthetase of these strains to feedback inhibition by tryptophan. These results support the concept that inhibition of enzyme activities rather than enzyme repression is more important in the regulation of aromatic amino acid biosynthesis in
H. polymorpha
.
Nonsusceptibility of Lizards Exposed to the Entomopathogen
Bacillus sphaericus
Authors: Hudson David M.
Published: January 2020

Tropical and subtropical lizards of the genus
Anolis
were exposed to
Bacillus sphaericus
Neide strain 1593-4, which has been proposed as a safe entomopathogen specific for mosquitoes. No deleterious effects were observed in lizards exposed to live bacteria through intraperitoneal injection or aerosol spray. Bacteria were lost quickly from lizard livers but were detectable at least 37 days after intraperitoneal injection.
Partial Purification and Characterization of Hemolysin from a Psychrotrophic Kanagawa-Positive Marine Vibrio
Authors: Peters Susan , Baross John A. , Morita Richard Y.
Published: January 2020

Psychrotrophic Kanagawa-positive marine vibrios were isolated from soft-shelled clams (
Mya arenaria
) collected in Yaquina Bay, Oreg. The 235 vibrio isolates obtained were screened for Gram reaction and morphology, Kanagawa reaction on Wagastsuma agar, and response to selected biochemical tests. The vibrio selected for further study was grown in broth, and the hemolysin was precipitated from a cleared supernatant with solid ammonium sulfate. The hemolytic substance was partially purified by DEAE-cellulose and Sephadex G-100 column chromatography. The hemolysin contained protein essential for activity, was thermolabile, and was more active against rabbit erythrocytes at 37°C than at lower temperatures. The molecular weight was estimated at 55,000 by using a Sephadex G-100 column. Hemolytic activity was partially inactivated by gangliosides and lowered against horse erythrocytes. The hemolysin did not react with antibody prepared against vibriolysin from
Vibrio parahaemolyticus
WP-1 by the Ouchterlony method. The hemolysin was high in aspartic and glutamic acids and low in arginine and histidine. Electrophoresis on a sodium dodecyl sulfate-polyacrylamide gel gave three major bands. The hemolysin from a psychrotrophic vibrio and the hemolytic exotoxin of
V. parahaemolyticus
had some similar and dissimilar characteristics. The possibility that a
Vibrio
sp. other than
V. parahaemolyticus
might serve as the reservoir for the Kanagawa phenotype is discussed.
Method for Studying Microbial Biofilms in Flowing-Water Systems
Authors: Pedersen Karsten
Published: January 2020

A method for the study of microbial biofilms in flowing-water systems was developed with special reference to the flow conditions in electrochemical concentration cells. Seawater was circulated in a semiclosed flow system through biofilm reactors (3 cm s
−1
) with microscope cover slips arranged in lamellar piles parallel with the flow. At fixed time intervals cover slips with their biofilm were removed from the pile, stained with crystal violet, and mounted on microscope slides. The absorbances of the slides were measured at 590 nm and plotted against time to give microbial biofilm development. From calibration experiments a staining time of 1 min and a rinse time of 10 min in a tap water flow (3 cm s
−1
) were considered sufficient. When an analysis of variance was performed on biofilm development data, 78% of the total variance was found to be due to random natural effects; the rest could be explained by experimental effects. The absorbance values correlated well with protein N, dry weight, and organic weight in two biofilm experiments, one with a biofilm with a high (75%) and one with a low (∼25%, normal) inorganic content. Comparisons of regression lines revealed that the absorbance of the stained biofilms was an estimate closely related to biofilm dry weight.
Correlations Between Predominant Heterotrophic Bacteria and Physicochemical Water Quality Parameters in Two Canadian Rivers
Authors: Bell C. R. , Holder-Franklin M. A. , Franklin M.
Published: January 2020

The heterotrophic bacterial populations in two contrasting rivers have been examined over a period of 1 year. The populations were analyzed (i) as total heterotrophic counts, (ii) as species numbers, using numerical taxonomy, (iii) by diversity indices, and (iv) by factor analysis. Isolates were obtained by plating directly from water samples and by chemostat enrichment. Four factors emerged which profiled the bacterial community and were common to both rivers. They were, in order of decreasing importance, fermentative metabolism, inorganic nitrogen metabolism, fluorescence-oxidative metabolism, and lack of starch hydrolysis. Several factors produced significant correlations with a range of physicochemical parameters, which were also measured. The correlations suggested an intricate algal-bacterial interaction. The oxidative metabolism factor correlated with rainfall in one river, suggesting that the oxidative bacteria may be washed in from the surrounding land. In the other river, the oxidative-fermentative factor correlated negatively with sunshine. Factor analysis was the most effective method for revealing correlations between bacterial characteristics and the environmental parameters; however, the use of a variety of methods provided more insight into the ecological aspects.
Determination of the Number of Respiring
Thiobacillus ferrooxidans
Cells in Water Samples by Using Combined Fluorescent Antibody-2-(
p
-Iodophenyl)-3-(
p
-Nitrophenyl)-5-Phenyltetrazolium Chloride Staining
Authors: Baker Katherine H. , Mills Aaron L.
Published: January 2020

Fluorescent antibody staining was combined with 2-(
p
-iodophenyl)-3-(
p
-nitrophenyl)-5-phenyltetrazolium chloride reduction in a procedure termed FAINT to allow for the direct microscopic determination of specific actively respiring populations of bacteria in a variety of aquatic habitats. The FAINT procedure is simple, precise, and appropriate for use in a wide variety of autecological studies. The distribution of
Thiobacillus ferrooxidans
was examined by FAINT enumerations in both acidic and nonacidic sites. Comparisons among the FAINT technique and fluorescent antibody staining alone or most-probable-number determinations in 9K broth showed that the use of most-probable-number determinations resulted in an underestimation of the number of viable cells by one to three orders of magnitude, whereas fluorescent antibody counts resulted in an overestimation of the number of viable
T. ferrooxidans.
The amount of difference was not consistent but varied, depending on the sample site.
Effect of incremental doses of radiation on viability of the microbial population on synthetic operating room gowns
Authors: Whitby J L , Storey D G
Published: January 2020

A total of 700 25-cm2 samples of surgical gown material were exposed to doses of cobalt-60 radiation of 0.0 to 0.6 Mrad in 0.1-Mrad increments. Pour plates were made, and the microbial colonies that arose were enumerated, isolated, and identified as to species. The death rate of the microbial population was calculated, and the mean D10 value of 0.269 Mrad was obtained. Analysis showed that the initial population on unirradiated material had been underestimated; when the counts obtained by homogenization of unirradiated material were substituted, a corrected mean D10 value of 0.249 Mrad was obtained. The isolates obtained were identified, and 70.7% were found to be Bacillus spp. with 12 different species identified, 16.2% were Micrococcus spp. with 6 different species identified, and 8.2% were fungi with 10 different species identified. Calculations were made for appropriate doses of radiation to sterilize gowns with this contaminating microbial population. These calculations gave an estimated dose of radiation of 1.98 to 1.81 Mrad to reduce the observed population to 0.001, a standard where 1 gown in 1,000 might contain a living organism. Comparison of the radiation resistance of this population with that of others reported in the literature showed good agreement.
Apparent and Measured Rates of Nitrification in the Hypolimnion of a Mesotrophic Lake
Authors: Hall Grahame H.
Published: January 2020

Three distinct phases were observed in the change of dissolved inorganic nitrogen concentrations in the hypolimnion of Grasmere. The second phase of decreasing ammonia and increasing nitrate concentrations was typical of the nitrification process. Observations on nitrate concentration gradients between surface sediments and the water column and experiments using the nitrification inhibitor N-Serve indicated the in situ activity of chemolithotrophic nitrifying organisms. Nitrification rates were estimated throughout the period of stratification by using the N-Serve and [
14
C]bicarbonate uptake method. Comparison of the field nitrate concentrations with the predicted nitrate concentrations (from estimates of the nitrification rate) indicated that the method underestimated the true rate of nitrification. Possible reasons for this are discussed.
Intermediary Metabolism of Organic Matter in the Sediments of a Eutrophic Lake
Authors: Lovley Derek R. , Klug Michael J.
Published: January 2020

The rates, products, and controls of the metabolism of fermentation intermediates in the sediments of a eutrophic lake were examined.
14
C-fatty acids were directly injected into sediment subcores for turnover rate measurements. The highest rates of acetate turnover were in surface sediments (0- to 2-cm depth). Methane was the dominant product of acetate metabolism at all depths. Simultaneous measurements of acetate, propionate, and lactate turnover in surface sediments gave turnover rates of 159, 20, and 3 μM/h, respectively. [2-
14
C]propionate and [
U
-
14
C]lactate were metabolized to [
14
C]acetate,
14
CO
2
, and
14
CH
4
. [
14
C]formate was completely converted to
14
CO
2
in less than 1 min. Inhibition of methanogenesis with chloroform resulted in an immediate accumulation of volatile fatty acids and hydrogen. Hydrogen inhibited the metabolism of C
3
-C
5
volatile fatty acids. The rates of fatty acid production were estimated from the rates of fatty acid accumulation in the presence of chloroform or hydrogen. The mean molar rates of production were acetate, 82%; propionate, 13%; butyrates, 2%; and valerates, 3%. A working model for carbon and electron flow is presented which illustrates that fermentation and methanogenesis are the predominate steps in carbon flow and that there is a close interaction between fermentative bacteria, acetogenic hydrogen-producing bacteria, and methanogens.
Improved growth medium for Campylobacter species
Authors: Mehlman I J , Romero A
Published: January 2020

Campylobacter species were grown in a base containing proteose peptone no. 3, yeast extract, K2HPO4, (NH4)2SO4, NA2SO3, soluble starch, and agar. Concentrations and sources of organic nitrogen and growth factors were critical, and the optimal pH range was 7.0 to 7.5. Cultures tolerated 0.7% NaCl in addition to the salt present in the organic constituents and were sensitive to surface-active agents at concentrations recommended for enrichment of other gram-negative bacteria. Cultures were maintained on the proposed medium for 1 year with transfer every 2 weeks.
Toxic substance from a natural bloom of Microcystis aeruginosa
Authors: Watanabe M F , Oishi S
Published: January 2020

A toxic substance contained in the blue-green alga Microcystis aeruginosa was purified and partially characterized. Toxic algal cells were collected from a highly eutrophic lake in Japan, and the toxin was purified by homogenization, ultrafiltration, gel filtration, and ion-exchange chromatography. The final preparation gave a single peak on high-performance liquid chromatography. The toxicity was somewhat less than that reported for other toxins from this alga. The water extract of 6.7 mg (dry weight) of cells and 72 microgram of the purified protein was required to kill a mouse (1 mouse unit). The main amino acids of the toxin were glutamic acid, asparatic acid, alanine, glycine, arginine, and leucine. The molecular weight of the toxin was 2,950 as determined by high-performance liquid chromatography.
Comparative antimicrobial activity, in vitro and in vivo, of soft N-chloramine systems and chlorhexidine
Authors: Selk S H , Pogány S A , Higuchi T
Published: January 2020

Antimicrobial activity of the following four new N-chloramine compounds was evaluated: two chlorinated simple amino acids, a chlorinated half-ester of succinic acid, and a chlorinated half-ester of glutaric acid. For comparison, the known bactericidal agents 3-chloro-4,4-dimethyl-2-oxazolidinone and chlorhexidine were evaluated by the same procedure. The contact germicidal efficiency screen was used to examine the in vitro bactericidal activity of all six compounds in the absence and presence of 5% horse serum or 5% Triton X-100. The four new compounds were found to have greater germicidal activity than the other compounds tested and to exhibit low toxicity and skin irritation values. The in vivo bactericidal activity was evaluated in two studies. In the occlusion test, three of the four new compounds plus chlorhexidine diacetate were tested. The N-chloramines were significantly superior to chlorhexidine in preventing the expansion of the normal flora under occlusion. In the scrub test, a gloved-hand wash method was used to compare the antimicrobial effect of a 1% solution of the chlorinated half-ester of succinic acid in triacetin with that of a commercial germicidal hand wash containing 4% chlorhexidine gluconate. The two preparations exhibited essentially the same hand-degerming activity.
Prevalence of Yersinia enterocolitica in waters of the lower Chippewa River Basin, Wisconsin
Authors: Meadows C A , Snudden B H
Published: January 2020

Water samples collected over a 14-month period from the lower Chippewa River drainage basin in Wisconsin were examined for Yersinia enterocolitica with either MacConkey-Tween 80 agar or Y-M agar (T. N. Saari and G. P. Jansen, Contrib. Microbiol. Immunol. 5:185-196) as the selective medium. A new method of isolation was developed. Of 303 water samples, 8.25% were positive. A seasonal variation was noticed, with winter isolations being most frequent.
Isolation of enteroviruses from oxidation pond waters
Authors: Sheladia V L , Ellender R D , Johnson R A
Published: January 2020

Enteroviruses were isolated from influent and effluent wastewaters of two types of oxidation lagoons during an 18-month study. Isolations, performed by sewage concentration and direct assay, were low in number and did not follow a seasonal trend. The younger treatment system, using aeration and effluent chlorination, was more efficient at removing viruses than the aging, static complex.
Glucuronide and sulfate conjugation in the fungal metabolism of aromatic hydrocarbons
Authors: Cerniglia C E , Freeman J P , Mitchum R K
Published: January 2020

Cunninghamella elegans oxidized naphthalene to ethyl acetate-soluble and water-soluble metabolites. Experiments with [14C]-naphthalene indicated that 21% of the substrate was converted into metabolites. The ratio of organic-soluble metabolites to water-soluble metabolites was 76:24. The major ethyl acetate-soluble naphthalene metabolites were trans-1,2-dihydroxy-1,2-dihydro-naphthalene, 4-hydroxy-1-tetralone, and 1-naphthol. Enzymatic treatment of the aqueous phase with either arylsulfatase or beta-glucuronidase released metabolites of naphthalene that were extractable with ethyl acetate. In both cases, the major metabolite was 1-naphthol. The ratio of water-soluble sulfate conjugates to water-soluble glucuronide conjugates was 1:1. Direct analysis of the aqueous phase by high-pressure liquid and thin-layer chromatographic and mass spectrometric techniques indicated that 1-naphthyl sulfate and 1-naphthyl glucuronic acid were major water-soluble metabolites formed from the fungal metabolism of naphthalene. C. elegans oxidized biphenyl primarily to 4-hydroxy biphenyl. Deconjugation experiments with biphenyl water-soluble metabolites indicated that the glucuronide and sulfate ester of 4-hydroxy biphenyl were metabolites. The data demonstrate that sulfation and glucuronidation are major pathways in the metabolism of aromatic hydrocarbons by fungi.
Microbial Activities in Undecompressed and Decompressed Deep-Seawater Samples
Authors: Jannasch Holger W. , Wirsen Carl O.
Published: January 2020

Microbial transformations of
14
C-labeled substrates (sodium glutamate, Casamino Acids, glucose, and sodium acetate) were measured in undecompressed seawater samples collected from depths of 1,800 to 6,000 m, during 14- to 21-day incubation periods at in situ temperature (3°C). Each substrate was tested at two concentrations (ca. 0.5 and 5.0 μg/ml) and two in situ pressures. The data were compared to 1-atmosphere (ca. 1.013 × 10
2
kPa) controls. The rates of
14
C incorporation and
14
CO
2
production as well as the amounts of total substrate utilization were generally lower at pressure than in the decompressed controls but were significantly different for each of the four substrates used. The utilization of acetate was the least affected by pressure; rates were similar to those measured at 1 atmosphere in two out of four experiments. In contrast, transformation rates of the amino acids at pressure averaged to only 38% of those in the controls. A single but reproducible “barophilic” response was observed with glucose as a substrate in samples collected from a depth of 4,500 m at a specific area in the northwestern Atlantic Ocean. Except for this latter set of experiments, the transformation of all substrates showed an increased lag period at pressure as compared to the 1-atmosphere controls.
Rates of Mineralization of Trace Concentrations of Aromatic Compounds in Lake Water and Sewage Samples
Authors: Rubin Howard E. , Subba-Rao R. V. , Alexander Martin
Published: January 2020

The rates of mineralization of phenol, benzoate, benzylamine,
p
-nitrophenol, and di(2-ethylhexyl) phthalate added to lake water at concentrations ranging from a few picograms to nanograms per milliliter were directly proportional to chemical concentration. The rates were still linear at levels of <1 pg of phenol or
p
-nitrophenol per ml, but it was less than the predicted value at 1.53 pg of 2,4-dichlorophenoxyacetate per ml. Mineralization of 2,4-dichlorophenoxyacetate was not detected in samples of lake water containing 200 ng of the chemical per ml. The slope of a plot of the rate of phenol mineralization in samples of three lakes as a function of its initial concentration was lower at levels of 1 to 100 μg/ml than at higher concentrations. In lake water and sewage supplemented with <60 ng of
14
C-labeled benzoate or phenylacetate per ml, 95 to 99% of the radioactivity disappeared from solution, indicating that the microflora assimilated little or none of the carbon. The extent of mineralization of some compounds in samples of two lakes and sewage was least in the water with the lowest nutrient levels. No mineralization of 2,4-dichlorophenoxyacetate and the phthalate ester was observed in samples of an oligotrophic lake. These data suggest that mineralization of some chemicals at concentrations of <1 μg/ml is the result of activities of organisms different from those functioning at higher concentrations or of organisms that metabolize the chemicals at low concentrations but assimilate little or none of the substrate carbon.
Flagella and Pili of Iron-Oxidizing Thiobacilli Isolated from a Uranium Mine in Northern Ontario, Canada
Authors: DiSpirito Alan A. , Silver Marvin , Voss Lance , Tuovinen Olli H.
Published: January 2020

Five strains of
Thiobacillus ferrooxidans
, which included three recent isolates from a uranium mine, possessed flagella. Three of the strains had several pili per cell. The dimensions, fine structure, and orientation of the flagella were different. Both polar and peritrichous flagella were observed, indicating strain-dependent ultrastructural variation in acidophilic thiobacilli. Neither flagella nor pili were detected in eight other strains of
T. ferrooxidans
and two strains of
Thiobacillus acidophilus
by electron microscopy, although all of the cultures contained motile cells.
Isolation and Properties of Ferromanganese-Depositing Budding Bacteria from Baltic Sea Ferromanganese Concretions
Authors: Ghiorse William C. , Hirsch Peter
Published: January 2020

Hyphal budding bacteria were observed by electron microscopy in thin sections of surface material from Baltic Sea ferromanganese concretions. Similar bacteria were also observed in and isolated from enrichment cultures prepared from the same concretion material. Three morphologically similar strains of Mn-Fe-depositing budding bacteria were isolated from the enrichment cultures. Strain B-4 possessed extracellular anionic polymers that accumulated Mn oxides. Mn deposition by B-4 was inhibited by elevated concentrations of Mn, 0.05% glutaraldehyde, 0.1 mM HgCl
2
, and heating at 93�C for 15 min, suggesting the participation of an enzyme protein in the Mn-depositing activity.
Asporogenous
Bacillus thuringiensis
Mutant Producing High Yields of δ-Endotoxin
Authors: Wakisaka Yoshiharu , Masaki Emiko , Koizumi Kenzo , Nishimoto Yoji , Endo Yasuhisa , Nishimura Masaji S. , Nishiitsutsuji-Uwo Junko
Published: January 2020

An asporogenous
Bacillus thuringiensis
subsp.
kurstaki
strain IK mutant, strain 290-1, which produced high yields of δ-endotoxin, was obtained by ethyl methane sulfonate treatment of a spore suspension. The mutant strain produced about the same amount of δ-endotoxin as that produced by the parent strain, but 10
10
to 10
11
cells did not form any detectable dormant spores.
Microbial models of mammalian metabolism: O-dealkylation of para-alkoxybiphenyls
Authors: Smith R V , Milton S A , Davis P J
Published: January 2020

The potential of selected microorganisms to O-dealkylate alkyl aryl ethers in a manner analogous to mammalian systems has been studied. A total of 45 fungi and actinomycetes were screened for their ability to O-demethylate 4-methoxybiphenyl. Of the 20 organisms found to actively metabolize this substrate, 5 were chosen for additional study. Incubation with a series of five homologous 4-alkoxybiphenyls, 4-methoxy-, 4-ethoxy, 4-(1-propoxy)-, 4-(2-propoxy)-, and 4-(1-butoxy)biphenyl, revealed that all were O-dealkylated by Aspergillus flavus ATCC 24741. With Triton X-100 as a solubilizing agent, the relative rates and extent of O-dealkylation of the 4-alkoxybiphenyls, were studied with A. flavus. The methoxy and ethoxy dervatives were dealkylated in more than 90% yield after 72 h of incubation, while the higher homologs were cleaved to the extent of only about 10%. An analogous pattern of O-dealkylation has been reported in mammalian systems.
Influences of pH, Temperature, and Moisture on Gaseous Tritium Uptake in Surface Soils
Authors: Fallon Robert D.
Published: January 2020

In South Carolina surface soils, the uptake of gaseous tritium (T
2
, HT, or both) showed a broad optimal temperature response from about 20 to 50°C, with the highest rates at 35 to 45°C. The optimal pH was in the range of 4 to 7. Uptake rates declined at the wet and dry extremes in soil moisture content. Inhibition seen upon the addition of hydrogen or carbon monoxide to the soil atmosphere suggested that hydrogenase may be responsible for T
2
-HT uptake in soil. During the period of most rapid recovery in a 36-day incubation of reinoculated, sterilized soil, T
2
-HT uptake rates doubled every 2 to 4 days. Thus, T
2
-HT uptake appears to be biologically mediated. Soil uptake of T
2
-HT was not severely limited by pH, temperature, or moisture in the soils tested. Thus, rapid exchange of gaseous tritium into soil water must be expected and accounted for in modeling the isotope distributions around nuclear facilities.
Large intestine bacterial flora of nonhibernating and hibernating leopard frogs (Rana pipiens)
Authors: Gossling J , Loesche W J , Nace G W
Published: January 2020

The bacteria in the large intestines of 10 northern leopard frogs (Rana pipiens) were enumerated and partially characterized. Four nonhibernating frogs were collected in the summer, four hibernating frogs were collected in the winter, and two frogs just emerged from hibernation were collected in the spring. All frogs had about 10(10) bacteria per g (wet weight) of intestinal contents and about 10(9) bacteria per g (wet weight) of mucosal scraping, although the counts from the winter frogs were slightly less than those from the other two groups of frogs. Another group of 14 summer frogs, after treatment to induce hibernation, showed a drop in bacterial counts accompanied by a change in the composition of the flora. In most frogs, Bacteroides was the dominant organism. Other bacteria repeatedly isolated at high dilutions were strict anaerobes, including butyrigenic and acetogenic helically coiled bacteria; fusobacteria; and acetogenic, small, gram-positive bacilli. These data indicate that the intestinal flora of frogs is similar to that of mammals and birds and that this flora can be maintained at temperatures close to freezing.
Heterotrophic activity and biodegradation of labile and refractory compounds by groundwater and stream microbial populations
Authors: Ladd T I , Ventullo R M , Wallis P M , Costerton J W
Published: January 2020

The bacteriology and heterotrophic activity of a stream and of nearby groundwater in Marmot Basin, Alberta, Canada, were studied. Acridine orange direct counts indicated that bacterial populations in the groundwater were greater than in the stream. Bacteria that were isolated from the groundwater were similar to species associated with soils. Utilization of labile dissolved organic material as measured by the heterotrophic potential technique with glutamic acid, phenylalanine, and glycolic acid as substrates was generally greater in the groundwater. In addition, specific activity indices for the populations suggested greater metabolic activity per bacterium in the groundwater. 14C-labeled lignocellulose, preferentially labeled in the lignin fraction by feeding Picea engelmannii [14C]phenylalanine, was mineralized by microorganisms in both the groundwater and the stream, but no more than 4% of the added radioactivity was lost as 14CO2 within 960 h. Up to 20% of [3'-14C]cinnamic acid was mineralized by microorganisms in both environments within 500 h. Both microbial populations appear to influence the levels of labile and recalcitrant dissolved organic material in mountain streams.
Inhibition of Expression of
Fusarium semitectum
and Other Fungi in Immature Cottonseed
Authors: Ciegler A. , Klich M. , Lee L.
Published: January 2020

Fusarium semitectum
Berkeley and Ravenel and other nonpathogenic fungi appear to contaminate immature cottonseed but cannot express themselves until immediately after seed maturation. It is hypothesized that catechin prevents fungal outgrowth and that inhibition is released when catechin is polymerized during seed maturation.
Bacteria on closed-boll and commercially harvested cotton
Authors: Millner P D , Ericson K E , Marsh P B
Published: January 2020

The bacterial content of specially treated cottons used by other investigators to test human pulmonary responses to cotton dust was examined. Cotton from Lubbock, Tex. and Stoneville, Miss. were either (i) harvested by machine and handled as commercial bale cotton, (ii) harvested as closed bolls with bracts intact and opened under special conditions, (iii) harvested as closed bolls, with bracts being removed and opened under special conditions, or (iv) harvested by (stoneville only). Bacillus spp. were isolated from all samples and predominated in cotton from Stoneville. Enterobacter agglomerans was isolated from all but one sample, the Stoneville closed-boll bract-removed cotton, and predominated in Lubbock samples. Aerogenic and anaerogenic biogroups of E. agglomerans were isolated; only aerogenic strain b of E. agglomerans was present in samples from both locations. Klebsiella ozaenae and K. pneumoniae were isolated only from Lubbock samples. Cotton from Lubbock yielded 100 to 1,000 times more bacteria, both total and gram negative, than did comparably treated cotton from Stoneville. Thus, differences in growing and processing conditions at the two locations were associated with large differences in the bacterial content of the cotton, but harvesting green bolls and removing bracts had little effect. The bacterial content of Stoneville washed cotton, and it paralleled the differences reported (Boehlecke et al., Am. Rev. Respir, Dis. 123:152, 1981) in pulmonary function responses when subjects were exposed to dust (0.6 mg/m3) from these two cottons. Levels of gram-negative and total bacteria on all samples were comparable to those previously reported for field-weathered cottons from various locations throughout the world.
Improved Microautoradiographic Method to Determine Individual Microorganisms Active in Substrate Uptake in Natural Waters
Authors: Tabor Paul S. , Neihof Rex A.
Published: January 2020

We report a method which combines epifluorescence microscopy and microautoradiography to determine both the total number of microorganisms in natural water populations and those individual organisms active in the uptake of specific substrates. After incubation with
3
H-labeled substrate, the sample is filtered and, while still on the filter, mounted directly in a film of autoradiographic emulsion on a microscope slide. The microautoradiogram is processed and stained with acridine orange, and, subsequently, the filter is removed before microscopic observation. This novel preparation resulted in increased accuracy in direct counts made from the autoradiogram, improved sensitivity in the recognition of uptake-active (
3
H-labeled) organisms, and enumeration of a significantly greater number of labeled organisms compared with corresponding samples prepared by a previously reported method.