bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantitative High-Pressure Liquid Chromatography-Fluorescence Determination of Some Important Lower Fatty Acids in Lake Sediments
Authors: Hordijk Kees A. , Cappenberg Thomas E.
Published: January 2020

For the quantitative determination of traces of fatty acids in pore water, several gas and liquid chromatographic methods were tested and discussed. Direct determination by gas-liquid chromatography with the use of formic acid-saturated carrier gas was found to be the least laborious method, but it is only recommended for the determination of volatile acids such as acetate and higher homologs. For the determination of lactate and formate, a derivatization procedure is necessary. The determination of these acids as phenacyl or benzyl esters was complicated by contaminants in the reagents. For this reason, a high-pressure liquid chromatography procedure with 4-bromomethyl-7-methoxycoumarin as a fluorescent labeling reagent is preferred. With this method, lactic, acetic, and formic acids could be demonstrated simultaneously at the nanogram level in 5-ml samples. Profiles of these acids in the sediment of Lake Vechten were measured, and they showed correlations with sulfate-reducing and methanogenic bacterial activities.
Liposomes replace serum for cultivation of fermenting mycoplasmas
Authors: Cluss R G , Johnson J K , Somerson N L
Published: January 2020

Cholesterol and albumin are limiting factors in the growth of Mycoplasma species. These nutrients are usually supplied in the culture medium by the addition of serum. The growth of M. pneumoniae in a serum-free medium containing an ethanolic cholesterol suspension and albumin was about one-half the level attained in serum-containing medium. M. gallisepticum and M. fermentans were not cultivable in the cholesterol suspension medium even after supplements were included. In another culture medium containing phosphatidylcholine-cholesterol liposomes and albumin as serum replacements, the growth of M. pneumoniae was approximately equal to that in serum-containing medium, and the growth of M. gallisepticum and M. fermentans was significantly greater than that in medium containing serum. M. fermentans produced even higher yields in liposome medium supplemented with arginine. These fermenting mycoplasmas readily adapted to the liposome medium and by the fifth or sixth serial passage produced thick confluent growth on the lower surface of culture bottles. To obtain maximum growth, we serially transferred the mycoplasmas at least 10 times in serum-free medium before quantitations of growth were made. This is the first report of a serum-free mycoplasma medium of high growth-promoting ability.
Inexpensive Flow Microcalorimeter For Measuring Heat Production of Attached and Sedimentary Aquatic Microorganisms
Authors: Lock Maurice A. , Ford Tim E.
Published: January 2020

A relatively inexpensive flow microcalorimeter is described which is capable of detecting heat outputs as low as 3 μW (precision, �2%). Its use is illustrated on river epilithon (0.8 to 6.8 μW cm
−2
), river sand (9.8 μW cm
−3
), and marine sand (15.3 μW cm
−3
); however, it could be used to detect the heat output from any biotic material over which a flow of water can be passed, provided that such an action would not be disruptive to chemical and biological equilibria.
Novel Biotransformations of 7-Ethoxycoumarin by
Streptomyces griseus
Authors: Sariaslani F. Sima , Rosazza John P.
Published: January 2020

Biotransformation of 7-ethoxycoumarin by
Streptomyces griseus
resulted in the accumulation of two metabolites which were isolated and identified as 7-hydroxycoumarin and 7-hydroxy-6-methoxycoumarin. A novel series of biotransformation reactions is implicated in the conversion of the ethoxycoumarin substrate to these products, including
O
-deethylation, 6-hydroxylation to form a 6,7-dihydroxycoumarin catechol, and subsequent
O
-methylation. Either 7-hydroxycoumarin or 6,7-dihydroxycoumarin was biotransformed to 7-hydroxy-6-methoxycoumarin by
S. griseus.
Trace amounts of the isomeric 6-hydroxy-7-methoxycoumarin were detected when 6,7-dihydroxycoumarin was used as the substrate. Efforts to obtain a cell-free catechol-
O
-methyltransferase enzyme system from
S. griseus
were unsuccessful. However, [
methyl
-
14
C]methionine was used with cultures of
S. griseus
to form 7-hydroxy-6-[
14
C]methoxycoumarin.
Microbial Transformation of Macrocyclic Trichothecenes
Authors: Pavanasasivam Gowsala , Jarvis Bruce B.
Published: January 2020

A resting culture of
Rhizopus arrhizus
(ATCC 11145) transformed verrucarin A into 16-hydroxyverrucarin A, whereas
R. arrhizus
transformed verrucarin B into a mixture of 16-hydroxyverrucarin B and 3′-hydroxyverrucarin A. Relative to verrucarins A and B, the 16-hydroxy derivatives showed marked increases in activity, as tested in vivo against P388 mouse leukemia.
Technique for Enumeration of Heterotrophic and Phototrophic Nanoplankton, Using Epifluorescence Microscopy, and Comparison with Other Procedures
Authors: Caron David A.
Published: January 2020

A new method is described that uses the fluorochrome primulin and epifluorescence microscopy for the enumeration of heterotrophic and phototrophic nanoplankton (2 to 20 μm). Phototrophic microorganisms are distinguished from heterotrophs by the red autofluorescence of chlorophyll
a
. Separate filter sets are used which allow visualization of the primulin-stained nanoplankton without masking chlorophyll
a
fluorescence, thus allowing easy recognition of phototrophic cells. Comparison with existing epifluorescence techniques for counting heterotrophic and phototrophic nanoplankton shows that primulin provides more accurate counts of these populations than the fluorescein isothiocyanate or proflavine techniques. Accuracy is comparable to that with the acridine orange technique, but this method requires only one filter preparation for the enumeration of both phototrophic and heterotrophic populations.

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Weighing Technique for Determining Bacterial Dry Mass Based on Rate of Moisture Uptake
Authors: O'Toole Desmond K.
Published: January 2020

Weights were recorded at 30-s intervals timed from initial exposure of dried cells to atmosphere. Linear regressions of data over 3 min gave moisture-free dry mass estimates.
Isolation and Characterization of a Xylanase from
Bacillus subtilis
Authors: Bernier Roger , Desrochers Michel , Jurasek Lubomir , Paice Michael G.
Published: January 2020

Partial characterization of an extracellular xylanase isolated by chromatography from
Bacillus subtilis
gave a molecular weight of 32,000 and optimum pH and temperature of 5.0 and 50�C, respectively.

K
m

and
V
max
values, determined with a soluble larchwood xylan, were 0.16% and 7.0 � 10
3
μmol min
−1
mg
−1
of enzyme respectively. The amino acid composition showed more basic amino acid residues than in a previously characterized xylanase from a white-rot fungus.
Phenylacetic acid stimulation of cellulose digestion by Ruminococcus albus 8
Authors: Stack R J , Hungate R E , Opsahl W P
Published: January 2020

The rate of cellulose digestion by Ruminococcus albus 8 grown on a defined medium could be increased by adding a minimum of 6.6% (vol/vol) rumen fluid. Strain 8 was grown on half this concentration, and the culture medium before and after growth was analyzed by gas chromatography-mass spectrometry to determine which components of the rumen fluid were used. Phenylacetic acid was identified as the component needed to make the defined medium nutritionally equivalent to one supplemented with rumen fluid. [14C]phenylacetic acid fed to cultures of strain 8 was primarily incorporated into protein. Hydrolysis of protein samples and separation of the resulting amino acids showed that only phenylalanine was labeled. The results indicate that cellulose digestion by strain 8 was probably limited by phenylalanine biosynthesis in our previously reported medium. The data obtained on the utilization of other rumen fluid components, as well as on the production of metabolites, illustrate the potential usefulness of this method in formulating defined media to simulate those in nature.
Sensitivity of an Oligotrophic Lake Planktonic Bacterial Community to Oxygen Stress
Authors: Mikell Alfred T. , Parker Bruce C. , Simmons George M.
Published: January 2020

Dissolved oxygen at approximately four times normal saturation (42 mg liter
−1
) inhibited the growth and metabolism of summer planktonic bacteria in the surface water of alpine oligotrophic Mountain Lake (Giles County, Va.). Data were derived from growth of CFU on membrane filters,
d
-[
U
-
14
C]glucose incorporation into the extractable lipid of these CFU, and respiration and assimilation of
d
-[
U
-
14
C]glucose by lake water samples. Statistically significant (α < 0.05) differences were not detected in either CFU or
14
C incorporation in lipid when superoxide dismutase (30 U ml
−1
) or catalase (130 U ml
−1
) was added to the medium. Thus, exogenous oxygen by-products apparently are not responsible for the observed inhibition of growth and metabolism.
Properties and roles of bacterial symbionts of polyvinyl alcohol-utilizing mixed cultures
Authors: Shimao M , Saimoto H , Kato N , Sakazawa C
Published: January 2020

From several polyvinyl alcohol (PVA)-utilizing mixed cultures, two component bacterial strains essential for PVA utilization were isolated, and their properties and roles in PVA utilization were studied. Each pair of essential component strains consisted of a type I strain, which produced a PVA-degrading enzyme and constituted the predominant population of the mixed culture in PVA, and a type II strain, which produced a certain growth stimulant for the former strain. All of the type I strains were taxonomically identical and assigned as Pseudomonas sp. In contrast, type II strains were taxonomically different from each other, belonging to Pseudomonas spp. and Alcaligenes sp. PVA utilization occurred in each mixed culture of a type I strain with Pseudomonas putida VM15A as a substitute for the type II strain of the original pair and also in each mixed culture of a type II strain with Pseudomonas sp. VM15C. The growth rates of these substituted, mixed cultures differed from each other.
Effect of soluble carbohydrates on digestion of cellulose by pure cultures of rumen bacteria
Authors: Hiltner P , Dehority B A
Published: January 2020

The rate of cellulose digestion in the presence of either glucose or cellobiose was studied for the three predominant species of cellulolytic rumen bacteria: Ruminococcus albus, Ruminococcus flavefaciens, and Bacteroides succinogenes. When a soluble carbohydrate was added to cellulose broth, the lag phase of cellulose digestion was shortened. Presumably, this was due to greater numbers of bacteria, because increasing the size of the inoculum had a similar effect. Cellulose digestion occurred simultaneously with utilization of the soluble carbohydrate. The rate of cellulose digestion slowed markedly for B. succinogenes and R. flavefaciens and slowed less for R. albus after the cellobiose or glucose had been utilized, and was accompanied by a decrease in pH. Both the rate and the extent of cellulose digestion were partially inhibited when the initial pH of the medium was 6.3 or below. R. albus appeared to be less affected by a low-pH medium than were B. succinogenes and R. flavefaciens. When a soluble carbohydrate was added to the fermentation during the maximum-rate phase of cellulose digestion, the rate of cellulose digestion was not affected until after the soluble carbohydrate had been depleted and the pH had decreased markedly. Prolonged exposure of the bacteria to a low pH had little if any effect on their subsequent ability to digest cellulose. Cellulase activity of intact bacterial cells appeared to be constitutive in nature for these three species of rumen bacteria.
Degradation and total mineralization of monohalogenated biphenyls in natural sediment and mixed bacterial culture
Authors: Kong H L , Sayler G S
Published: January 2020

Mixed bacterial cultures obtained from polychlorinated biphenyl-contaminated river sediments are capable of degrading monohalogenated biphenyls under simulated natural conditions. Culture conditions include river water as supportive medium and mixed bacterial cultures obtained from river sediments. Degradation occurs when the substrates are supplied as the sole carbon source or when added together with glucose. The degradation rates of 2-, 3-, and 4-chlorobiphenyl, at 30 micrograms ml-1, were 1.1, 1.6, and 2.0 micrograms ml-1 day-1, respectively. Monobrominated biphenyls, including 2-, 3-, and 4-bromobiphenyl, were degraded at rates of 2.3, 4.2, and 1.4 micrograms ml-1 day-1, respectively. Metabolites, including halogenated benzoates, were detected by high-performance liquid chromatography and mass spectrometry. By using chlorophenyl ring-labeled monochlorobiphenyls as substrates, total mineralization (defined as CO2 production from the chlorophenyl ring) was observed for 4-chlorobiphenyl but not for 2-chlorobiphenyl. Rates of total mineralization of 4-chlorobiphenyl (at 39 to 385 micrograms ml-1 levels) were dependent on substrate concentration, whereas variation of cell number in the range of 10(5) to 10(7) cells ml-1 had no significant effects. Simulated sunlight enhanced the rate of mineralization by ca. 400%.
Adsorption of reovirus to clay minerals: effects of cation-exchange capacity, cation saturation, and surface area
Authors: Lipson S M , Stotzky G
Published: January 2020

The adsorption of reovirus to clay minerals has been reported by several investigators, but the mechanisms defining this association have been studied only minimally. The purpose of this investigation was to elucidate the mechanisms involved with this interaction. More reovirus type 3 was adsorbed, in both distilled and synthetic estuarine water, by low concentrations of montmorillonite than by comparable concentrations of kaolinite containing a mixed complement of cations on the exchange complex. Adsorption to the clays was essentially immediate and was correlated with the cation-exchange capacity of the clays, indicating that adsorption was primarily to negatively charged sites on the clays. Adsorption was greater with low concentrations of clays in estuarine water than in distilled water, as the higher ionic strength of the estuarine water reduced the electrokinetic potential of both clay and virus particles. The addition of cations (as chloride salts) to distilled water enhanced adsorption, with divalent cations being more effective than monovalent cations and 10(-2) M resulting in more adsorption than 10(-3) M. Potassium ions suppressed reovirus adsorption to montmorillonite, probably by collapsing the clay lattices and preventing the expression of the interlayer-derived cation-exchange capacity. More virus was adsorbed by montmorillonite made homoionic to various mono-, di-, and trivalent cations (except by montmorillonite homoionic to potassium) than by comparable concentrations of kaolinite homoionic to the same cations. The sequence of the amount of adsorption to homoionic montmorillonite was Al greater than Ca greater than Mg greater than Na greater than K; the sequence of adsorption to kaolinite was Na greater than Al greater than Ca greater than Mg greater than K. The constant partition-type adsorption isotherms obtained when the clay concentration was maintained constant and the virus concentration was varied indicated that a fixed proportion of the added virus population was adsorbed, regardless of the concentration of infectious particles. A heterogeneity within the reovirus population was indicated.
Rumen bacterial and fungal degradation of Digitaria pentzii grown with or without sulfur
Authors: Akin D E , Gordon G L , Hogan J P
Published: January 2020

Sheep fed the forage Digitaria pentzii fertilized with sulfur were compared with those fed unfertilized forage for the rumen microbial population involved with fiber degradation. No differences were detected in the bacterial population as determined by anaerobic cultures on a habitat-simulating medium, xylan, or pectin, by 35S labeling techniques for microbial protein, or by transmission electron microscopic studies of bacterium-fiber interactions. Rumen volume and water flow from the rumen were not different for sheep fed each of the forages. Rumen fungi were prevalent in sheep fed sulfur-fertilized D. pentzii as shown by sporangia adhering to forage fiber and by colonies developing from zoospores in roll tubes with cellobiose plus streptomycin and penicillin. Fungi were absent or in extremely small numbers in sheep fed unfertilized forage. Nylon bag digestibility studies showed that the fungi preferentially colonized the lignified cells of blade sclerenchyma by 6 h and caused extensive degradation by 24 h. In the absence of bacteria in in vitro studies, extensive hyphal development occurred; other lignified tissues in blades (i.e., mestome sheath and xylem) were attacked, resulting in a residue with partially degraded and weakened cell walls. Nonlignified tissues were also degraded. Breaking force tests of leaf blades incubated in vitro with penicillin and streptomycin and rumen fluid from sheep fed sulfur-fertilized forage or within nylon bags in such sheep showed a residue at least twice as fragile as that from sheep fed unfertilized forage. In vitro tests for dry matter loss showed that rumen fungi, in the absence of actively growing bacteria, could remove about 62% of the forage material. The response of rumen fungi in sheep fed sulfur-fertilized D. pentzii afforded a useful in vivo test to study the role of these microbes in fiber degradation. Our data establish that rumen fungi can be significant degraders of fiber and further establish a unique role for them in attacking and weakening lignocellulosic tissues. The more fragile residues resulting from attack by fungi could explain the greater intake consistently observed by sheep eating sulfur-fertilized compared with unfertilized D. pentzii forage.
Colloidal clay inhibits conjugal transfer of R-plasmid R1drd-19 in Escherichia coli
Authors: Singleton P
Published: January 2020

Colloidal clay (montmorillonite) strongly inhibited the conjugal transfer of R-plasmid R1drd-19 in Escherichia coli. This finding is discussed in the context of the feasibility of plasmid transfer in environmental waters.
Effects of Pentachloronitrobenzene and Some of Its Known and Possible Metabolites on Fungi
Authors: Renner Gerhard , Ruckdeschel Gotthard
Published: January 2020

Fungicidal activities of pentachloronitrobenzene and derivatives were tested with
Candida albicans, Aspergillus fumigatus, Trichophyton rubrum, Trichophyton mentagrophytes
, and
Microsporon canis.
In relation to pentachloronitrobenzene, no increasing fungistatic activities were found with cysteine derivatives. Rising fungistatic activities were seen with pentachlorophenylmethylsulfone and, in some of the strains, with pentachloronitrosobenzene, pentachlorothiophenol, pentachlorophenol, pentachloroaniline, pentachlorophenylmethylsulfoxide, the isomeric tetrachloronitrobenzenes, tetrachlorothiophenols, tetrachlorophenols, and tetrachloroanilines.
Freeze-Recovery Physiology of Nitrogenase Activity in Terrestrial
Nostoc
sp. Colonies
Authors: DuBois John D. , Kapustka Lawrence A.
Published: January 2020

Nostoc
sp. colonies from field collections were cultured and propagated on silica sand with aqueous N-free BG-11 medium. Laboratory experiments were conducted to characterize the in vivo freeze-recovery physiology of nitrogenase activity. Nitrogenase activity was monitored by the acetylene reduction technique. Frozen
Nostoc
sp. colonies were thawed and warmed to 10, 15, 20, 25, or 30°C. At 25 and 30°C, nitrogenase activity was detected within 6 h after thawing. At 20°C or lower, nitrogenase activity was not detected until 12 h after thawing. Optimum thawing temperature with respect to the recovery of nitrogenase activity was 25°C. In subsequent experiments, laboratory-grown
Nostoc
colonies were used along with the following conditions: prefreezing treatment of 3 days of exposure to light or darkness, freezing, and then thawing to 25°C in light or darkness with or without metabolic inhibitors [3-(3,4-dichlorophenyl)-1, 1-dimethylurea (DCMU), monofluoroacetate, or chloramphenicol]. Approximately 30% of the energy in the initial recovery of nitrogenase activity (to 12 h after thawing) appeared to be supplied via the utilization of carbon compounds stored before freezing. Photosynthetic conditions (i.e., light and without DCMU) were necessary for maximum recovery of nitrogenase activity. In the presence of the protein synthesis inhibitor chloramphenicol, nitrogenase activity was still detected at 12 to 48 h after thawing. Although damage may occur to nitrogenase, some of the enzyme was capable of surviving the freeze-thaw period in vivo. However, complete recovery of nitrogenase activity (equal to prefreezing activity) may entail some de novo synthesis of nitrogenase.
Influence of Calcium and Manganese on Dechaining of
Lactobacillus bulgaricus
Authors: Wright Catherine T. , Klaenhammer Todd R.
Published: January 2020

The events responsible for the transition of
Lactobacillus bulgaricus
1243-F from long filamentous chains to short bacilloid rods were examined in a cation-depleted liquid medium. In the presence of magnesium only, cells grew as long chains of unseparated cells. The addition of 100 μM to 1 mM calcium or manganese to this medium resulted in the dechaining of these cells to short bacilloid rods. Fe
2+
, Zn
2+
, Co
2+
, and Cu
2+
failed to induce dechaining. Induction of calcium and manganese dechaining functioned under controlled pH maintained at 5.0 and 6.0 but not at pH 7.0. This was consistent with a previous report showing failure in synthesis of dechaining enzymes by
L. bulgaricus
under pH conditions approaching alkalinity (S. K. Rhee and M. Y. Pack, J. Bacteriol.
144:
865-868, 1980). We conclude that under pH conditions which permit synthesis of dechaining enzymes, calcium and manganese are necessary for dechaining activity.
Microthrix parvicella, a filamentous bacterium isolated from activated sludge: cultivation in a chemically defined medium
Authors: Slijkhuis H
Published: January 2020

A large number of media have been tested for cultivating Microthris parvicella, a filamentous microorganism often present in the activated sludge of oxidation ditches. The bacterium was found to utilize oleic acid (preferably as Tween 80) as the sole source of carbon and energy. Sulfur is required in the reduced form. The tested media vary from a complex to a chemically defined medium. Growth yields of 1.3 to 1.5 g/liter were obtained on media containing Tween 80 (4 g/liter), reduced nitrogen and reduced sulfur compounds, calcium and magnesium salts, phosphate buffer, trace elements, thiamin, and cyanocobalamin. The optimum temperature for growing the organism is approximately 25 degrees C, and the pH of the nutrient medium should be above 7.
GELRITE as an Agar Substitute in Bacteriological Media
Authors: Shungu Daniel , Valiant Mary , Tutlane Vicki , Weinberg Ellen , Weissberger Barbara , Koupal Larry , Gadebusch Hans , Stapley Edward
Published: January 2020

GELRITE gellan gum (formerly known as PS-60 and S-60) is a new naturally derived, highly purified polysaccharide which displays several interesting properties, including selfgelling. The suitability of GELRITE as an agar substitute was tested by evaluating the performance of several media selected from among those most commonly used in the isolation, identification, and enumeration of microorganisms in clinical laboratories. Fifty different bacterial species previously implicated in human infections served as test strains. On the basis of the various parameters considered, namely, colony characteristics, biochemical reactions, hemolytic patterns, and plating efficiency, media gelled by agar and by GELRITE compared quite favorably.
Medium Promoting Sporulation of
Bacillus larvae
and Metabolism of Medium Components
Authors: Dingman D. W. , Stahly Donald P.
Published: January 2020

A new medium, designated TMYGP broth, was developed that allowed the honeybee pathogen
Bacillus larvae
NRRL B-3650 to produce up to 5 × 10
8
spores per ml of culture (microscopic count). This species normally sporulates poorly, if at all, in artificial broth media. An aeration rate lower than that normally used to cultivate other
Bacillus
species was required for sporulation. During the exponential growth phase, acids were produced by catabolism of yeast extract components, causing a decrease in pH of the medium. Thereafter, the pH began to increase, probably because of derepression of the citric acid cycle and consumption of the acids. Only after this time did usage of glucose from the medium occur. Thus, glucose usage seems to be regulated by catabolite repression. The presence of glucose was needed for one or more of the later events of sporulation. Of many substances tested, only gluconic acid and glucosamine partially substituted for glucose as a requirement for sporulation. Pyruvate was also required for good sporulation. It was metabolized during the late-exponential phase of growth.
Interaction of
Agromyces ramosus
with Other Bacteria in Soil
Authors: Casida L. E.
Published: January 2020

Agromyces ramosus
occurs in very high numbers in most soils and, based on studies of laboratory isolates, does not require host cells for growth. Nevertheless, it attacked and destroyed most of the gram-positive and gram-negative bacterial species tested as possible host organisms.
A. ramosus
also attacked and destroyed
Saccharomyces cerevisiae.
The possibility of attack on fungi was unclear. Among the bacteria serving as hosts were the important soil species
Azotobacter vinelandii, Rhizobium leguminosarum, Rhizobium meliloti
, and
Agrobacterium tumefaciens.
Dead cells were not attacked.
A. vinelandii
cysts were attacked but left unharmed. To some extent,
A. vinelandii
seemed to survive this attack by encysting. Attack by
A. ramosus
occurred in natural soil and over a broad range of nutritional levels in laboratory media. The attack did not seem to be a means for obtaining an increased supply of commonly available nutrients. Instead, it seemed to be a means of obtaining something produced, perhaps in small amounts, by a variety of organisms, but not by all organisms. Several types of culture filtrates were tested for activity. The filtrates neither stimulated nor inhibited the growth of
A. ramosus
or the host organisms. The availability of catalase activity in host organisms did not seem to be involved. It is not known whether the attack by
Agromyces ramosus
in soil can be manipulated to cause a decrease in numbers of
Agrobacterium tumefaciens
or other pathogens without simultaneously depressing the numbers of beneficial organisms in this habitat.
Survival of human parainfluenza viruses in the South Polar environment
Authors: Parkinson A J , Muchmore H G , Scott E N , Scott L V
Published: January 2020

The survival of human parainfluenza virus types 1, 2, and 3 was measured in both indoor and outdoor environments at South Pole Station, Antarctica, in an effort to determine the long-term survival of these viruses in this environment and to identify the possible source of respiratory tract illnesses which occurred in this isolated population in 1978 after 10 and 27 weeks of total social isolation. Viruses were applied to plastic petri plate surfaces which were then stored in indoor (21.4 degrees C; water vapor density, 1.50 g of water per m3) and outdoor environments (-22.4 to -33.2 degrees C; water vapor density, 0.706 and 0.247 g of water per m3). Parainfluenza virus type 1 at an initial titer of 3.75 log10 50% tissue culture infective doses per ml was inactivated after 4 days at room temperature and after 7 days outside. Parainfluenza virus type 2 and 3 at initial titers of 5.58 and 5.38 log10 50% tissue culture infective doses per ml were inactivated after 7 and 12 days, respectively, at room temperature and after 17 days of storage outside. Results indicate that the long-term survival of parainfluenza virus in either environment for up to 10 weeks is unlikely and probably did not provide the source of infectious virus responsible for the midisolation outbreaks of parainfluenza virus-related respiratory tract illnesses observed in this population during the 1978 winter season.
Bacteriophages of methanotrophs isolated from fish
Authors: Tyutikov F M , Yesipova V V , Rebentish B A , Bespalova I A , Alexandrushkina N I , Galchenko V V , Tikhonenko A S
Published: January 2020

Bacteriophages of methanotrophic bacteria were isolated from 67 fish. Only two phages isolated from two fish species specifically lysed Methylocystis sp. and Flavobacterium gasotypicum. The phages lysing these species were designated 63-F and CMF-1-F, respectively. The isolated phages differed greatly in the fine structure of the virion, plaque morphology, spectrum of lytic action, serological properties, and UV sensitivity. At the same time, they had identical one-step growth characteristics: their latent period equalled 5 h, lysis time was 3 to 4 h, and burst size was about 240 virions. The phages had guanine- and cytosine-rich double-stranded DNAs consisting of common nitrogen bases. The molecular masses of the DNAs as determined by the sums of restriction endonuclease cleavage fragments were 28 X 10(6) daltons for phage 63-F and 31 X 10(6) daltons for phage CMF-1-F.
Toxicity studies of metabolites of some fungal isolates in albino mice
Authors: Pathak B , Sethi N , Gupta J , Vora V C
Published: January 2020

Crude metabolites of 21 of 60 fungal cultures isolated from some of the common cereals collected from different parts of India were found to be toxic. Of these toxin-producing fungi, 79% caused hepatic pathology of varying severity in mice. Serum glutamate pyruvate transaminase values and blood urea nitrogen were found to be high in such experimental animals.
Interaction of pH and NaCl on culture density of Clostridium botulinum 62A
Authors: Montville T J
Published: January 2020

Clostridium botulinum 62A growth rates declined with decreasing pH and increasing salt levels. Lysis rates, however, were affected only by pH. Due to competition between growth and lysis rates, an accurate assessment of interactive effects was obtained only when optical density determinations were made at multiple intervals.
Biodegradation and photolysis of pentachlorophenol in artificial freshwater streams
Authors: Pignatello J J , Martinson M M , Steiert J G , Carlson R E , Crawford R L
Published: January 2020

The biodegradation, photolysis, and adsorption of pentachlorophenol (PCP) in outdoor, aquatic environments were examined with man-made channels built by the U.S. Environmental Protection Agency at a field station on the Mississippi River near Monticello, Minn. Four channels were used, each channel being approximately 520 m long and receiving river water that flowed through the channels for about 10 h before reentering the river. The channels were dosed continuously during the summer of 1982 with various concentrations of PCP (approximately 0, 48, 144, and 432 micrograms/liter). We monitored the biotic and abiotic degradation of PCP in these channels for approximately 16 weeks. Photolysis of PCP was rapid at the water surface, but greatly attenuated with depth. Depending on sunlight conditions, photolysis accounted for a 5 to 28% decline in initial PCP concentration. Adsorption of PCP by sediment and uptake by biota accounted for less than 15% and probably less than 5% in unacclimated water. Microbial degradation of PCP became significant about 3 weeks after the initiation of dosing and eventually became the primary mechanism of PCP removal, accounting for a 26 to 46% (dose-dependent) decline in initial PCP. Most of the PCP-mineralizing microorganisms that developed in the channels were either attached to surfaces (e.g., rocks and macrophytes) or associated with surface sediments. Total bacterial numbers (direct microscopic counts) in the various channels were not affected significantly by PCP concentrations of micrograms per liter. Numerous strains of bacteria able to grow at the expense of PCP were isolated from the adapted channels. The experiments reported here will help predict the responses of flowing aquatic ecosystems to contamination by biocides such as pentachlorophenol.
Immunological Characterization of
Pectinatus cerevisiophilus
Strains
Authors: Haikara Auli
Published: January 2020

Eleven
Pectinatus cerevisiophilus
strains of brewery origin were classified serologically by gel diffusion precipitin tests, immunoelectrophoresis, and the fluorescent antibody staining technique. The
Pectinatus
strains could be assigned immunologically to three different groups. Groups I and III were found to be very closely related, and only some of the antisera used showed differences. The antisera against the strains belonging to group II contained a common group antigen. A strong precipitation band found near the antigen was shown to represent the interaction of the lipopolysaccharide antibody and the respective antigen.
Cloning and Expression of Thermostable α-Amylase Gene from
Bacillus stearothermophilus
in
Bacillus stearothermophilus
and
Bacillus subtilis
Authors: Aiba Shuichi , Kitai Kazuo , Imanaka Tadayuki
Published: January 2020

The structural gene for a thermostable α-amylase from
Bacillus stearothermophilus
was cloned in plasmids pTB90 and pTB53. It was expressed in both
B. stearothermophilus
and
Bacillus subtilis. B. stearothermophilus
carrying the recombinant plasmid produced about fivefold more α-amylase (20.9 U/mg of dry cells) than did the wild-type strain of
B. stearothermophilus.
Some properties of the α-amylases that were purified from the transformants of
B. stearothermophilus
and
B. subtilis
were examined. No significant differences were observed among the enzyme properties despite the difference in host cells. It was found that the α-amylase, with a molecular weight of 53,000, retained about 60% of its activity even after treatment at 80°C for 60 min.
Selection of Bacteria with Favorable Transport Properties Through Porous Rock for the Application of Microbial-Enhanced Oil Recovery
Authors: Jang Long-Kuan , Chang Philip W. , Findley John E. , Yen Teh Fu
Published: January 2020

This paper presents a bench-scale study on the transport in highly permeable porous rock of three bacterial species—
Bacillus subtilis, Pseudomonas putida
, and
Clostridium acetobutylicum
—potentially applicable in microbial-enhanced oil recovery processes. The transport of cells during the injection of bacterial suspension and nutrient medium was simulated by a deep bed filtration model. Deep bed filtration coefficients and the maximum capacity of cells in porous rock were measured. Low to intermediate (∼10
6
/ml) injection concentrations of cellular suspensions are recommended because plugging of inlet surface is less likely to occur. In addition to their resistance to adverse environments, spores of clostridia are strongly recommended for use in microbial-enhanced oil recovery processes since they are easiest among the species tested to push through porous rock. After injection, further transport of bacteria during incubation can occur by growth and mobility through the stagnant nutrient medium which fills the porous rock. We have developed an apparatus to study the migration of bacteria through a Berea sandstone core containing nutrient medium.
Sediment Nitrification, Denitrification, and Nitrous Oxide Production in a Deep Arctic Lake
Authors: Klingensmith K. M. , Alexander V.
Published: January 2020

We used a combination of
15
N tracer methods and a C
2
H
2
blockage technique to determine the role of sediment nitrification and denitrification in a deep oligotrophic arctic lake. Inorganic nitrogen concentrations ranged between 40 and 600 nmol · cm
−3
, increasing with depth below the sediment-water interface. Nitrate concentrations were at least 10 times lower, and nitrate was only detectable within the top 0 to 6 cm of sediment. Eh and pH profiles showed an oxidized surface zone underlain by more reduced conditions. The lake water never became anoxic. Sediment Eh values ranged from −7 to 484 mV, decreasing with depth, whereas pH ranged from 6.0 to 7.3, usually increasing with depth. The average nitrification rate (49 ng of N · cm
−3
· day
−1
) was similar to the average denitrification rate (44 ng of N · cm
−3
· day
−1
). In situ N
2
O production from nitrification and denitrification ranged from 0 to 25 ng of N · cm
−3
· day
−1
. Denitrification appears to depend on the supply of nitrate by nitrification, such that the two processes are coupled functionally in this sediment system. However, the low rates result in only a small nitrogen loss.
Binding Characteristics of Lectins Involved in the Trapping of Nematodes by Fungi
Authors: Rosenzweig W. D. , Ackroyd D.
Published: January 2020

Seventeen saccharides were tested for their ability to bind to the trap lectins of three species of nematode-trapping fungi and prevent nematode capture. The lectin of
Arthrobotrys conoides
was found to be inhibited by α-
d
-glucose/
d
-mannose and similar saccharides. The lectins of
Monacrosporium eudermatum
and
Monacrosporium rutgeriensis
were inhibited by α-
l
-fucose and 2-deoxy-
d
-glucose, respectively. Human group O(H) erythrocytes agglutinated to traps of
M. eudermatum
but not
A. conoides
or
M. rutgeriensis.
There was no agglutination of group A or B to traps formed by all three fungi. Exposure of the traps to trypsin eliminated the ability to capture nematodes. The presence of
d
-glucose/
d
-mannose and
l
-fucose residues on the nematode cuticle was suggested through the use of commercially prepared lectin-peroxidase conjugates.
Characterization of Lactobacillus sp. strain 100-37 from the murine gastrointestinal tract: ecology, plasmid content, and antagonistic activity toward Clostridium ramosum H1
Authors: McCormick E L , Savage D C
Published: January 2020

A gram-positive, nonsporulating, microaerophilic rod that had two colonial variants was obtained during a study in which anaerobic bacteria were isolated from murine gastrointestinal tracts and screened for cryptic plasmids. The rod (both colonial variants) was identified as a Lactobacillus sp. (strain 100-37) by selective media, gas chromatography, and biochemical tests. In monoassociated, ex-germfree mice, the bacterium colonized the gastrointestinal tract and formed a thick, continuous layer on the keratinized squamous epithelium of the nonsecreting portion of the stomach. When lysate preparations of both colonial variants were electrophoresed in agarose gels, two bands which stained with ethidium bromide were detected with each lysate. When the DNA preparations were exposed to UV light, the lower ethidium bromide band gradually disappeared while the top band became either broader or more intense. The approximate size of the lower band was 2.2 megadaltons, as determined by comparison with plasmid molecular weight standards. In a search for phenotypes which could be encoded by the cryptic 2.2-megadalton plasmid, we detected an antagonistic activity toward an obligate anaerobe isolated from mouse feces, Clostridium ramosum H1. The antagonistic factor was precipitated with (NH4)2SO4 (70% saturation) from supernatant solutions of broth cultures of strain 100-37. The factor was not inducible with mitomycin C or UV light, but was stable in flowing steam for up to 50 min, and in buffers of pHs over a range of 1.6 to 6.8. It was nondialyzable and inactivated by trypsin and papain.(ABSTRACT TRUNCATED AT 250 WORDS)
Expression of a Lactose Transposon (Tn
951
) in
Zymomonas mobilis
Authors: Carey V. C. , Walia S. K. , Ingram L. O.
Published: January 2020

The potential utility of
Zymomonas mobilis
as an organism for the commercial production of ethanol would be greatly enhanced by the addition of foreign genes which expand its range of fermentable substrates. We tested various plasmids and mobilizing factors for their ability to act as vectors and introduce foreign genes into
Z. mobilis
CP4. Plasmid pGC91.14, a derivative of RP1, was found to be transferred from
Escherichia coli
to
Z. mobilis
at a higher frequency than previously reported for any other plasmids. Both tetracycline resistance and the lactose operon from this plasmid were expressed in
Z. mobilis
CP4. Plasmid pGC91.14 was stably maintained in
Z. mobilis
at 30°C but rapidly lost at 37°C.
Regulation of 2,4,5-trichlorophenoxyacetic acid and chlorophenol metabolism in Pseudomonas cepacia AC1100
Authors: Karns J S , Duttagupta S , Chakrabarty A M
Published: January 2020

The expression of the degradative genes encoding 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), 2,4,5-trichlorophenol (2,4,5-TCP), and pentachlorophenol (PCP) dechlorination in a 2,4,5-T-degrading strain of Pseudomonas cepacia was examined during growth on alternate carbon sources. The dechlorination mechanisms for all three compounds were expressed in 2,4,5-T- and 2,4,5-TCP-grown cells but were not expressed in cells grown on succinate, glucose, or lactate. The addition of 2,4,5-TCP or PCP to cells grown on succinate or lactate resulted in the expression of the 2,4,5-TCP dechlorination mechanism in resting cells after 1-h lag. This expression was prevented by the presence of chloramphenicol in the resting cell suspension. Succinate-plus-PCP-grown resting cells preincubated with 2,4,5-TCP fully induced the trichlorophenol dechlorination system and partially induced the PCP dechlorination system. Preincubation of succinate-plus-PCP-grown resting cells with PCP induced neither the 2,4,5-TCP nor the PCP dechlorinating system. Succinate-grown resting cells converted 2,4,5-T to 2,4,5-TCP even in the presence of chloramphenicol. Thus, the data indicate that the enzyme(s) which converts 2,4,5-T to 2,4,5-TCP is constitutively expressed, whereas those that convert 2,4,5-TCP to central intermediates are induced by 2,4,5-TCP but not by 2,4,5-T or PCP and are repressed in the presence of an alternate carbon source.
Isolation of a Bacterium Capable of Degrading Peanut Hull Lignin
Authors: Kerr Thomas J. , Kerr Robert D. , Benner Ronald
Published: January 2020

Thirty-seven bacterial strains capable of degrading peanut hull lignin were isolated by using four types of lignin preparations and hot-water-extracted peanut hulls. One of the isolates, tentatively identified as
Arthrobacter
sp., was capable of utilizing all four lignin preparations as well as extracted peanut hulls as a sole source of carbon. The bacterium was also capable of degrading specifically labeled [
14
C]lignin-labeled lignocellulose and [
14
C]cellulose-labeled lignocellulose from the cordgrass
Spartina alterniflora
and could also degrade [
14
C]Kraft lignin from slash pine. After 10 days of incubation with [
14
C]cellulose-labeled lignocellulose or [
14
C]lignin-labeled lignocellulose from
S. alterniflora
, the bacterium mineralized 6.5% of the polysaccharide component and 2.9% of the lignin component.
Effect of Acidity on the Composition of an Indigenous Soil Population of
Rhizobium trifolii
Found in Nodules of
Trifolium subterraneum
L
Authors: Dughri Muktar H. , Bottomley Peter J.
Published: January 2020

Acidity affected which members of an indigenous soil population of
Rhizobium trifolii
nodulated
Trifolium subterraneum
L. cv. Mt. Barker. In three experiments involving plants grown either in mineral salts agar adjusted to pH 4.8 or 6.8 and inoculated with a soil suspension or grown directly in samples of unamended soil (pH 4.8) or soil amended with CaCO
3
(pH 6.4), 121 of 151 isolates of
R. trifolii
were placed into four serogroups. Seventy-nine of these isolates were placed into two serogroups (6 and 36) whose nodulating ability was affected by the pH of the plant root environment. Representatives of serogroup 6 occupied the greatest percentage of the nodules at the low pH in both mineral salts agar (77%) and in unlimed soil (47 and 57%). The same serogroup was a minor nodule occupant at the higher pH in mineral salts agar (0%) and in limed soil (0 and 10%). In contrast, serogroup 36 was virtually absent in nodules formed at the low pH, whereas it was the dominant serogroup at the higher pH in both mineral salts agar (32%) and in limed soil (35 and 49%). Despite the isolates from within each serogroup being antigenically identical, separation of cellular proteins by sodium dodecyl sulfate-polyacrylamide gradient gel electrophoresis revealed four and six different gel types within serogroups 6 and 36, respectively. Isolates represented by one or two gel types dominated the contribution of each serogroup to the nodule population. Further evidence for differences between isolates within each gel type were revealed from measurements of symbiotic effectiveness.
Enhancement of Goldfish Virus Type 2 Replication by 1- Naphthol, the Major Hydrolysis Product of the Pesticide Carbaryl
Authors: Shea Thomas B.
Published: January 2020

The major hydrolysis product of the pesticide carbaryl, 1-naphthol, enhanced the replication of goldfish virus type 2 in piscine cell culture at concentrations below any detectable cytotoxicity. Enhancement indices of 2.3, 3.7, and 7.1 were observed at 1, 5, and 10 ppm (μl/liter), respectively. Replication at 0.5 ppm was equivalent to that of controls.
Vibrio cholerae (non-O1) isolated from California coastal waters
Authors: Kenyon J E , Gillies D C , Piexoto D R , Austin B
Published: January 2020

Nineteen strains of Vibrio cholerae non-O1 were isolated from five separate marine sites along the Santa Cruz County coast. This environmental study was initiated after a human case of non-O1 cholera-like diarrhea was acquired endemically.
Optimal enrichment time for isolation of Vibrio parahaemolyticus from seafood
Authors: Dupray E , Cormier M
Published: January 2020

The growth of Vibrio parahaemolyticus in a liquid medium was compared with that of human fecal flora and estuarine flora. No marked differences were noted between growth at 25 and 37 degrees C for V. parahaemolyticus. However, the marine organisms were strongly inhibited when incubated at 37 degrees C. Incubation for 8 h in an enrichment broth yielded V. parahaemolyticus growth, even with a small inoculum, whereas the marine and fecal floras were inhibited. Therefore, enrichment for 8 h at 37 degrees C appears to be optimal for isolation of V. parahaemolyticus, permitting more rapid results in seafood analysis.
Detection of Salmonella spp. in milk by using Felix-O1 bacteriophage and high-pressure liquid chromatography
Authors: Hirsh D C , Martin L D
Published: January 2020

A method is described whereby the presence of less than five salmonellae was detected per milliliter of milk within 24 h of sample collection. Salmonellae were removed from milk by means of electropositive large-pore filters. Eluates from the filters were analyzed for the presence of Salmonella spp. by Felix-O1 bacteriophage and high-pressure liquid chromatographic techniques. The method gave only a positive response when salmonellae were present in the milk. Of the serotypes and strains of Salmonella spp. tested, Salmonella dublin (10 strains), Salmonella typhimurium (5 strains), Salmonella anatum, Salmonella krefeld, and Salmonella saint-paul gave positive responses. One strain of Salmonella agona (three strains tested) and three strains of Salmonella enteritidis (seven strains tested) were not detectable by the method described herein.