bluuebunny/crossref_metadata_2025 huggingface dataset:
Accumulation of Soybean Lectin-Binding Polysaccharide During Growth of
Rhizobium japonicum
as Determined by Hemagglutination Inhibition Assay
Authors: Tsien H. C. , Schmidt E. L.
Published: January 2020

A hemagglutination inhibition assay was used to estimate the presence of soybean lectin-binding polysaccharide in whole culture, culture supernatant, and isolated exopolysaccharide of
Rhizobium japonicum
USDA 138. The occurrence of 0.1 to 0.2 μg of lectin-binding polysaccharide could be detected within 2 h with a 0.5-ml total sample. Lectin-binding polysaccharide was detected in all preparations during both exponential and stationary growth phases. The formation of lectin-binding polysaccharide was not, whereas that of total exopolysaccharide was, markedly affected by culture conditions.
Survival of human enteroviruses in the Hawaiian ocean environment: evidence for virus-inactivating microorganisms
Authors: Fujioka R S , Loh P C , Lau L S
Published: January 2020

The stability of certain human enteroviruses in the Hawaiian ocean environment was examined. The present data indicated that the time for 90% reduction of poliovirus type 1 at 24 +/- 1 degree C in seawater samples obtained from different sites in Hawaii ranged from 24 to 48 h, and complete inactivation occurred within 72 to 96 h. The accumulated evidence also strongly indicated that a virus-inactivating agent(s) of a microbiological nature was present in both clean and sewage-polluted seawaters, but not in fresh, mountain stream waters. The antiviral activity was lost when the seawater samples were subjected to boiling, autoclaving, or filtration through a 0.22- or 0.45-micrometer, but not a 1.0-micrometer, membrane filter. That the antiviral activity of the seawater was related to the growth activities of microorganisms was corroborated by the observed effects of added nutrients, a lower temperature of incubation, and the presence of certain antibiotics. Other enteric viruses, such as coxsackie virus B-4 and echo virus-7, were also shown to be similarly inactivated in seawater.
New Selective Growth Inhibitors of
Sphaerotilus natans
, Anslimins A and B
Authors: Takiguchi Yo , Yoshikawa Hiroji , Terao Michiya
Published: January 2020

Selective growth inhibitors of
Sphaerotilus natans
were detected in the culture broths of several strains of
Streptomyces
. Anslimins A and B were isolated from the culture broth of
Streptomyces oganonensis
by adsorption on resinous adsorbent followed by elution with 50% aqueous acetone. The A and B components were then separated by cellulose powder chromatography. Physicochemical parameters of anslimins A and B revealed that these compounds are new peptide-containing structures. Anslimins A and B inhibited growth of
S. natans
at 0.78 and 0.39 μg/ml, respectively, but showed no activity against any of the other test microorganisms at 100 to 200 mg/ml. The anslimins had no harmful effect on guppies at a concentration of 100 mg/liter.
Membrane filtration of dairy products for microbiological analysis
Authors: Peterkin P I , Sharpe A N
Published: January 2020

Incubation with protease or Tween 80 or both dramatically improved the membrane filterability of liquid milks, powdered skim milk, and frozen dairy products without reducing the viability of five common species of bacteria. The technique can permit isolation and enumeration of microorganisms from test samples of these foods as large as 5 g. Flow direction through the filter was an important factor in filterability of dairy products.
Effects of wastewater sludge and its detergents on the stability of rotavirus
Authors: Ward R L , Ashley C S
Published: January 2020

Wastewater sludge reduced the heat required to inactivate rotavirus SA-11, and ionic detergents were identified as the sludge components responsible for this effect. A similar result was found previously with reovirus (R. L. Ward and C. S. Ashley, Appl. Environ. Microbiol 36:889-897, 1978). The quantitative effects of individual ionic detergents on rotavirus and reovirus were very different, and rotavirus was found to be extremely sensitive to several of these detergents. However, neither virus was destabilized by nonionic detergents. On the contrary, rotavirus was stabilized by a nonionic detergent against the potent destabilizing effects of the ionic detergent sodium dodecyl sulfate. The destabilizing effects of both cationic and anionic detergents on rotavirus were greatly altered by changes in the pH of the medium.
Thiosulfate Oxidation and Tetrathionate Reduction by Intact Cells of Marine Pseudomonad Strain 16B
Authors: Tuttle Jon H.
Published: January 2020

Levels of thiosulfate-oxidizing enzyme (TSO) and tetrathionate reductase (TTR) were measured in washed cell suspensions of a heterotrophic marine thiosulfate-oxidizing bacterium, strain 16B. TSO activity remained virtually constant in aerobically and anaerobically grown cells and was unaffected by the presence or absence of thiosulfate and tetrathionate in the growth medium. TTR was also present in cells grown aerobically and anaerobically, but its activity was threefold greater in cells cultured in media containing tetrathionate or thiosulfate. Tetrathionate appears to be the inducer of increased TTR activity in both aerobically and anaerobically grown cells. TTR (constitutive or induced) and TSO have different pH and temperature optima. Both TTR activities were unaffected by 10 mM KCN, which reversed oxygen inhibition of tetrathionate reduction. TSO was partially inhibited by 5 μM KCN and completely inhibited by 90 μM KCN. These findings and results of experiments to determine the influence of several inorganic electron donors and acceptors on TSO and TTR activities suggest that constitutive TSO and TTR represent reverse activities of the same enzyme, whereas inducible TTR is a separate enzyme used by strain 16B only for anaerobic respiration of tetrathionate. The bacterium appears well adapted to growth in environments characterized by low oxygen tension, dilute organic carbon concentrations, and the presence of a variety of reduced, inorganic sulfur compounds.
Isolation and identification of pathogenic microorganisms at wastewater-irrigated fields: ratios in air and wastewater
Authors: Teltsch B , Kedmi S , Bonnet L , Borenzstajn-Rotem Y , Katzenelson E
Published: January 2020

Samples of air and corresponding wastewater samples were taken at wastewater spray-irrigated fields. The concentrations of salmonellae and enteroviruses present in these samples were determined and compared with those of coliforms, and the ratios between them were calculated. The most common Salmonella serotype in the air was Salmonella ohio, whereas in the wastewater, Salmonella anatum was the most common. Enteroviruses isolated and identified were poliovirus, echovirus, and coxsackievirus type B. From the ratios of salmonellas to coliforms and enteroviruses to coliforms in the air, as compared to these ratios in the wastewater, it was concluded that the suitability of coliforms as an indication of airborne contamination caused by spray irrigation is questionable.
Microbial activity of trench leachates from shallow-land, low-level radioactive waste disposal sites
Authors: Francis A J , Dobbs S , Nine B J
Published: January 2020

Trench leachate samples collected anoxically from shallow-land, low-level radioactive waste disposal sites were analyzed for total aerobic and anaerobic populations, sulfate reducers, denitrifiers, and methanogens. Among the several aerobic and anaerobic bacteria isolated, only Bacillus sp., Pseudomonas sp., Citrobacter sp., and Clostridium sp. were identified. Mixed bacterial cultures isolated from the trench leachates were able to grow anaerobically in trench leachates, which indicates that the radionuclides and organic chemicals present were not toxic to these bacteria. Changes in concentrations of several of the organic constituents of the waste leachate samples were observed due to anaerobic microbial activity. Growth of a mixed culture of trench-water bacteria in media containing a mixture of radionuclides, 60Co, 85Sr, and 134,137Cs, was not affected at total activity concentrations of 2.6 X 10(2) and 2.7 X 10(3) pCi/ml.
Anaerobic Degradation of Uric Acid by Gut Bacteria of Termites
Authors: Potrikus C. J. , Breznak John A.
Published: January 2020

A study was done of anaerobic degradation of uric acid (UA) by representative strains of uricolytic bacteria isolated from guts of
Reticulitermes flavipes
termites.
Streptococcus
strain UAD-1 degraded UA incompletely, secreting a fluorescent compound into the medium, unless formate (or a formicogenic compound) was present as a cosubstrate. Formate functioned as a reductant, and its oxidation to CO
2
by formate dehydrogenase provided 2H
+
+ 2e
−
needed to drive uricolysis to completion. Uricolysis by
Streptococcus
UAD-1 thus corresponded to the following equation: 1UA + 1formate → 4CO
2
+ 1acetate + 4NH
3
. Urea did not appear to be an intermediate in CO
2
and NH
3
formation during uricolysis by strain UAD-1. Formate dehydrogenase and uricolytic activities of strain UAD-1 were inducible by growth of cells on UA.
Bacteroides termitidis
strain UAD-50 degraded UA as follows: 1UA → 3.5 CO
2
+ 0.75acetate + 4NH
3
. Exogenous formate was neither required for nor stimulatory to uricolysis by strain UAD-50. Studies of UA catabolism by
Citrobacter
strains were limited, because only small amounts of UA were metabolized by cells in liquid medium. Uricolytic activity of such bacteria in situ could be important to the carbon, nitrogen, and energy economy of
R. flavipes
.
Contamination of broiler carcass skin during commercial processing procedures: an electron microscopic study
Authors: Thomas C J , McMeekin T A
Published: January 2020

Scanning and transmission electron microscopy were used in conjunction with normal microbiological cultural techniques to examine some aspects of contamination of broiler carcass skin by bacteria during processing. The autochthonous skin microflora of poultry, before processing, was mainly Micrococcus spp. which were located in accumulations of sebum-like substances on the surface of the stratum corneum. During scalding and plucking, the skin epidermis was removed, and exposed dermal tissue was contaminated by microorganisms from the mechanical plucker and subsequent stages of processing. Major sources of psychrotrophic contamination were the immersion washer and chiller water. Microbial contaminants were found within a fluid film on the skin surface and inside deep skin channels. Skin microtopography and the presence of the liquid film were implicated as major factors controlling contamination during processing.
Incorporation of Specific Fatty Acid Precursors During Spore Germination and Outgrowth in
Bacillus thuringiensis
Authors: Nickerson Kenneth W. , Bulla Lee A.
Published: January 2020

The selective incorporation of precursors specific for individual fatty acids in germinating and outgrowing spores of
Bacillus thuringiensis
is described. The specific precursors utilized were [
14
C]butyrate, -isobutyrate, -valerate, and -isovalerate, which were incorporated into even-numbered normal-chain isomers, even-numbered iso-isomers, odd-numbered normal-chain acids, and odd-numbered isohomologs, respectively. This preferential incorporation by
B. thuringiensis
allows the terminal carbons of specific normal and branched-chain fatty acids, contained within the cytoplasmic membrane, to be labeled with
14
C and, potentially,
13
C.
Inhibition of Bacteria by Lactulose Preparations
Authors: Huhtanen C. N. , Parrish F. W. , Hicks K. B.
Published: January 2020

Lactulose syrups were similar to sucrose syrups in water activity-lowering effects but were more inhibitory toward test microorganisms. Heat-treated commercial lactulose syrups were most inhibitory, whereas non-heat-treated pure lactulose was only slightly more inhibitory than sucrose.
Production of
l
-Glutamine by a Penicillin-Resistant Mutant of
Flavobacterium rigense
Authors: Nabe Koichi , Ujimaru Toshihiko , Izuo Nobuhiko , Yamada Shigeki , Chibata Ichiro
Published: January 2020

To establish a practical method for the fermentative production of
l
-glutamine, cultural conditions for the accumulation of a large amounts of
l
-glutamine were investigated by using
Flavobacterium rigense
703, which was previously reported by us as a
l
-glutamine-producing mutant. As a result, a yield of 25 mg of
l
-glutamine per ml was obtained after a 48-h cultivation in a medium containing glucose, yeast extract, (NH
4
)
2
-fumarate, KH
2
PO
4
, K
2
HPO
4
, MgSO
4
.7H
2
O, and CaCO
3
(pH 6.4). Accumulation of
l
-glutamine was dependent upon the concentration of (NH
4
)
2
-fumarate, and a suboptimum growth at a relatively high concentration of (NH
4
)
2
-fumarate was essential for the maximum production of
l
-glutamine. At the optimum conditions, glutamic acid was formed as a by-product at a concentration of less than 1 mg/ml, but accumulation of the other amino acids was negligible. The product was isolated from the culture broth and readily purified by anion-exchange chromatography. The pure crystals of
l
-glutamine obtained in an 80% yield were optically and chromatographically pure.
Branched-chain amino acid transport in Streptococcus agalactiae
Authors: Moran J W
Published: January 2020

The transport of the branched-chain amino acids in Streptococcus agalactiae was characterized. Glucose-grown cells were able to utilize only glucose as an energy source for transport of L-leucine, whereas lactose-grown cells could utilize both glucose and lactose. It was determined from metabolic inhibitor studies that energy from glycolysis and substrate level phosphorylation was required for active transport. Energy was found to be coupled to transport by the action of adenosine triphosphatase and the generation of a proton motive force. The branched-chain amino acids were found to share a common transport system that may consist of multiple components.
Factor Analysis of the Impact of the Environment on Microbial Communities in the Tvärminne Area, Southern Coast of Finland
Authors: Väätänen Pentti
Published: January 2020

Data already examined by regression analysis were subjected to factor analysis to scrutinize the effects of environmental factors on microbial populations in the brackish waters of the Tvärminne archipelago on the southern coast of Finland. Water samples were collected from 1.0-m depth at one point in Tvärminne Storfjärd, 71 times over about 2 years. Twenty-six parameters were determined on each sample, 10 of environmental and 16 of microbiological type. The correlations between the parameters were factorized using the principal axis solution, and eight factors chosen for further consideration were rotated by the varimax method. The major part of the variance (about 90% of the total communality) of the microbiological parameters was covered by five factors, interpreted as phytoplankton blooms, the periods before and after the blooms, freshwater outflows, and water temperature. Wind variables were components in the factors interpreted as freshwater outflows. Rainfall played a minor part in the total variance of the microbial community, but it washed yeasts and proteolytic bacteria from the land into the study area. The eight factors selected covered about 60 to 98% of the variance of the microbiological parameters. The highest values (above 90%) were obtained for direct counts of bacteria, for plate counts of mesophilic and polymyxin-resistant bacteria, and for the two community respiration parameters; the lowest values (60 to 75%) were obtained for H
2
S-producing and proteolytic bacteria.
Mutation induced by drying of Escherichia coli on a hydrophobic filter membrane
Authors: Asada S , Takano M , Shibasaki I
Published: January 2020

Drying of Escherichia coli to a required cellular water level was conducted on a hydrophobic membrane at the corresponding relative humidity. Mutation from an arginine auxotroph to the prototroph was induced by drying to a water activity (aw) of 0.53 and below, but not to an aw of 0.75 and above. The critical aw below which mutation occurred in the course of drying was similar to that for induction of deoxyribonucleic acid (DNA) strand breakage in the bacteria. Some ultraviolet or gamma-irradiation-sensitive strains, e.g., strains of carrying recA, recB, and uvrA recA were more sensitive to drying than the wild-type strains or strains carrying uvrA and polA. The DNA strand breakage of every strain was observed to be to a similar extent after drying to an aw of less than 0.53. The drying-resistant strains repaired the damaged DNA partially during postdrying incubation in a growth medium but not in phosphate buffer solution, while the drying-sensitive strains could not at all. Significant mutation on drying occurred in the wild-type strains, strains carrying uvrA and polA, but not in strains carrying recA. It is, therefore, concluded that the mutation is caused by errors in rec-dependent repair of the drying-induced breakage in DNA.
Investigation of Salmonella infection in goats fed corn silage grown on land fertilized with sewage sludge
Authors: Ayanwale L F , Kaneene J M , Sherman D M , Robinson R A
Published: January 2020

A total of 36 goats were fed for 17 months with corn silage grown on land fertilized with human sewage sludge. These animals were investigated for salmonella infections. Salmonellae were not detected in cultures of fecal or silage samples. No significant agglutination titers were detected in goat sera examined. Salmonella newport C2 was isolated from the sludge used as fertilizer on the cornfields. The public health aspects of the findings are discussed as they relate to the increasing use of sewage sludge for agricultural fertilizers, as well as to the resultant effects on human food and livestock feed.
Inhibition of Aspergillus growth and aflatoxin release by derivatives of benzoic acid
Authors: Chipley J R , Uraih N
Published: January 2020

A study was conducted to determine the effects of o-nitrobenzoate, p-aminobenzoate, benzocaine (ethyl aminobenzoate), ethyl benzoate, methyl benzoate, salicylic acid (o-hydroxybenzoate), trans-cinnamic acid (beta-phenylacrylic acid), trans-cinnamaldehyde (3-phenylpropenal), ferulic acid (p-hydroxy-3-methoxycinnamic acid), aspirin (o-acetoxy benzoic acid), and anthranilic acid (o-aminobenzoic acid) upon growth and aflatoxin release in Aspergillus flavus NRRL 3145 and A. parasiticus NRRL 3240. A chemically defined medium was supplemented with various concentrations of these compounds and inoculated with spores, and the developing cultures were incubated for 4, 6, and 8 days at 27 degree C in a mechanical shaker. At the beginning of day 8 of incubation, aflatoxins were extracted from cell-free filtrates, separated by thin-layer chromatography, and quantitated by ultraviolet spectrophotometry. The structure of these aromatic compounds appeared to be critically related to their effects on mycelial growth and aflatoxin release. At concentrations of 2.5 and 5.0 mg per 25 ml of medium, methyl benzoate and ethyl benzoate were the most effective in reducing both mycelial growth and aflatoxin release by A. flavus and A. parasiticus. Inhibition of mycelial growth and aflatoxin release by various concentrations of the above-named aromatic compounds may indicate the possibility of their use as fungicides.
Heat damage to the chromosome of Escherichia coli K-12
Authors: Pellon J R , Ulmer K M , Gomez R F
Published: January 2020

The folded chromosome or nucleoid of Escherichia coli was analyzed by low-speed sedimentation in neutral sucrose gradients after in vivo heat treatment. Heat treatment of cultures at 50 degree C for 15, 30, and 60 min resulted in in vivo association of the nucleoids with cellular protein. Structural changes, determined by the increase in speed dependence of the nucleoids from heated cells, also occurred. These changes were most likely due to the unfolding of the typical compact nucleoid structure. The nucleoids from heated cells also had notably higher sedimentation coefficients (3,000 to 4,500S) than nucleoids from control cells (1,800S). These nucleoids did not contain greater than normal amounts of membrane phospholipids or ribonucleic acid. We propose that the protein associated with the nucleoids from heated cells causes the observed sedimentation coefficient increases.
Degradation of
14
C-Labeled Lignins and
14
C-Labeled Aromatic Acids by
Fusarium solani
Authors: Norris Dale M.
Published: January 2020

Abilities of isolate AF-W1 of
Fusarium solani
to degrade the side chain and the ring structure of synthetic dehydrogenative polymerizates, aromatic acids, or lignin in sound wood were investigated under several conditions of growth substrate or basal medium and pH. Significant transformations of lignins occurred in 50 days in both unextracted and extracted sound wood substrates with 3% malt as the growth substrate and the pH buffered initially at 4.0 with 2,2-dimethylsuccinate. Degradation of lignin in such woods also occurred under unbuffered pH conditions when a basal medium of either 3% malt or powdered cellulose in deionized water was present. Decomposition of the lignin in these woods did not occur in cultures where
d
-glucose was present as a growth substrate.
F. solani
significantly transformed, as measured as evolved
14
CO
2
, both synthetic side chain (β, γ)-
14
C- and
U
-ring-
14
C-labeled lignins in 30 days under liquid culture conditions of only distilled deionized water and no pH adjustment. Degradation of dehydrogenative polymerizates by
F. solani
was reduced drastically when D
2
was the liquid medium. AF-W1 also cleaved the α-
14
C from
p
-hydroxybenzoic acid and evolved
14
CO
2
from the substrate, [3-
14
C]cinnamic acid. Thus, the fungus cleaved side chain carbon from substrate that originally lacked hydroxyl substitution on the aromatic nucleus. Surprisingly, small amounts of
14
C cleaved from aromatic acids by
F. solani
were incorporated into cell mass. Initial buffering of the culture medium to pH 4.0 or 5.0 with 0.1 M 2,2-dimethylsuccinate significantly increased
F. solani
degradation of all lignins or aromatic acids. Results indicated that AF-W1 used lignin as a sole carbon source.
Characterization of Two New Facultative Methanotrophs
Authors: Lynch Martha J. , Wopat Ann E. , O'Connor Mary L.
Published: January 2020

Two new facultative methane-oxidizing bacteria have been isolated from lake water enrichments. The organisms have been characterized in terms of colony types, growth characteristics, the guanine plus cytosine content of their deoxyribonucleic acid, thin sections, oxidation rates, and carbon assimilation pathways. Methane-grown cells of both organisms contained intracytoplasmic membranes similar to those described as type II in other methanotrophic bacteria. Neither organism had such membranes when grown heterotrophically. Both organisms assimilated methane by way of the isocitrate lyase-negative serine pathway for formaldehyde incorporation. The enzymes of this pathway were high in specific activity in cells grown on methane and were at low levels in cells grown either on heterotrophic substrates or on heterotrophic substrates plus methane. It is proposed that both organisms be classified in the genus
Methylobacterium
as two new species,
Methylobacterium ethanolicum
and
Methylobacterium hypolimneticum.
Multichannel photometer-nephelometer
Authors: Keilmann F , Böhme D , Santo L
Published: January 2020

We describe an instrument for monitoring either transmitted or scattered light intensity, or both, simultaneously on up to eight channels. The use of a laser light source (at 632.8-nm wavelength) provides high accuracy and dynamic range: optical density can be measured from 0.0004 up to 6, and a scattered light fraction down to 10(-6) can be resolved. Built-in thermostat and magnetic stirrers allow precise monitoring of aqueous microbial growth over a practical range of 4 orders of magnitude of cell concentration.
Ethanol from Sugar Cane: Flask Experiments Using the EX-FERM Technique
Authors: Rolz Carlos , de Cabrera Sheryl
Published: January 2020

Alcohol production at the laboratory scale from sugar cane pieces by the EX-FERM technique was studied with 37 strains of
Saccharomyces
spp. The EX-FERM process is novel in that it employs the simultaneous extraction and fermentation of the sucrose in a cane-water suspension. Two types of cane treatments were used: chips and shredded pith, either fresh or dried. A mother culture of the yeast was prepared in enriched cane juice and then added to the cane-water mixture. After static fermentation for 40 h at 30°C, the cane was removed, and fresh cane was added to the yeast-alcohol broth. After an additional 24 h, the cane was again removed and the liquor was analyzed. After the first 40-h cycle, sugar consumption was above 99% with 10 of the 37 yeast strains tested, and ethanol reached levels of 1.29 to 4.00 g per 100 ml, depending on the yeast strain. The final ethanol concentration reached 4.27 to 5.37 g per 100 ml, and sugar consumption was above 98% in three cases during a second EX-FERM cycle employing previously air-dried chips and pith. Product yields were within accepted values. Cane treatment did not appear to affect the results at this level.
Incidence of R factors in coliform, fecal coliform, and Salmonella populations of the Red River in Canada
Authors: Bell J B , Macrae W R , Elliott G E
Published: January 2020

Coliforms, fecal coliforms, and Salmonella were isolated from the Red River, Manitoba, Canada, and identified. These organisms were then examined for resistance to 12 antibiotics. Some fecal coliforms were resistant to all 12 antibiotics, and 18% of the Salmonella isolates were resistant to one or more antibiotics. A total of 52.9% of the fecal coliforms resistant to three or more antibiotics were able to transfer single or multiple resistance (R) determinants to the Salmonella recipient, and 40.7% could transfer R determinants to the Escherichia coli recipient. Of the resistant Salmonella, 57% transferred one or two determinants to the Salmonella recipient, and 39% transferred one or two determinants to the E. coli recipient. It was calculated that populations of fecal coliforms containing R factors were as high as 1,400 per 100 ml and that an accidental intake of a few milliliters of water could lead to transient or permanent colonization of the digestive tract. Consideration of data on bacteria with R factors should be made in future water quality deliberations and in discharge regulations.
Evidence Suggesting Protozoan Predation on
Rhizobium
Associated with Germinating Seeds and in the Rhizosphere of Beans (
Phaseolus vulgaris
L.)
Authors: Ramirez Carlos , Alexander Martin
Published: January 2020

Changes in populations of microorganisms around germinating bean (
Phaseolus vulgaris
L.) seeds, in the rhizosphere of bean, and in a model rhizosphere were studied. Strains of
Rhizobium phaseoli
that were resistant to streptomycin and thiram were used, and as few as 300
R. phaseoli
cells per g of soil could be enumerated with a selective medium that was devised. A direct role was not evident for bacterial competitors, lytic bacteria, antibiotic-producing microorganisms, bacteriophages, and
Bdellovibrio
in the suppression of
R. phaseoli
around germinating seeds and in the rhizosphere. Protozoa increased in numbers in the soil upon planting of the seeds. The extent of colonization of soil by
R. phaseoli
was inversely related to the presence of large numbers of bacteria and protozoa. Colonization of
R. phaseoli
was improved upon suppression of protozoa with thiram and also when the soil was amended with other protozoan inhibitors and mannitol to simulate seed and root exudation. The data support the view that the decrease in numbers of
R. phaseoli
is caused by an increase in protozoan predation, the protozoa increasing in number because they prey on bacteria that proliferate by using seed and root exudates as nutrients.
Organic Carbon Utilization by Resting Cells of Thiosulfate-Oxidizing Marine Heterotrophs
Authors: Tuttle Jon H.
Published: January 2020

Two thiosulfate-oxidizing marine heterotrophs, strains 12W and 16B, were tested for utilization of [
14
C]glucose and [
14
C]acetate, respectively, in the presence or absence of thiosulfate. Thiosulfate oxidation caused an increase in organic carbon incorporation and a corresponding decrease in respiration at pH 6.5, near the optimum pH for thiosulfate oxidation and thiosulfate-stimulated growth in these bacteria. The amount of glucose or acetate metabolized remained virtually unaffected by thiosulfate oxidation. The metabolic shift in carbon utilization was diminished by increasing the initial pH to 8.0. The results indicate that marine heterotrophs 12W and 16B exhibit a type of mixotrophic metabolism which differs from that observed in the thiobacilli.
Fluorometric Determination of Adenosine Nucleotide Derivatives as Measures of the Microfouling, Detrital, and Sedimentary Microbial Biomass and Physiological Status
Authors: Davis William M. , White David C.
Published: January 2020

Adenosine, adenine, cyclic adenosine monophosphate (AMP), AMP, nicotinamide adenine dinucleotide, adenosine diphosphate, and adenosine triphosphate (ATP) were recovered quantitatively from aqueous portions of lipid extracts of microfouling, detrital, and sedimentary microbial communities. These could be detected quantitatively in the picomolar range by forming their 1-N
6
-etheno derivatives and analyzing by high-pressure liquid chromatography with fluorescence detection. Lipid extraction and subsequent analysis allowed the simultaneous measurement of the microbial community structure, total microbial biomass with the quantitative recovery of the adenine-containing cellular components, which were protected from enzymatic destruction. This extraction and fluorescent derivatization method showed equivalency with the luciferin-luciferase method for bacterial ATP measurements. Quick-freezing samples in the field with dry ice-acetone preserved the ATP and energy charge (a ratio of adenosine nucleotides) for analysis at remote laboratories. The metabolic lability of ATP in estuarine detrital and microfouling communities, as well as bacterial monocultures of constant biomass, showed ATP to be a precarious measure of biomass under some conditions. Combinations of adenosine and adenine nucleotides gave better correlations with microbial biomass measured as extractable lipid phosphate in the detrital and microfouling microbial communities than did ATP alone. Stresses such as anoxia or filtration are reflected in the rapid accumulation of intracellular adenosine and the excretion of adenosine and AMP into the surrounding milieu. Increases in AMP and adenosine may prove to be more sensitive indicators of metabolic status than the energy charge.
Incidence of salmonellae in fecal samples of production swine and swine at slaughter plants in the United States in 1978
Authors: McKinley G A , Fagerberg D J , Quarles C L , George B A , Wagner D E , Rollins L D
Published: January 2020

Nine swine slaughter plants and 19 swine production units were randomly selected for sampling from the six highest swine-producing states representing a total of 64% of the United States swine production. Three composites of 10 fresh swine fecal samples were obtained from each slaughter plant, representing three different farm sources of swine. Two composite fecal samples were collected from two different production pens from each production unit. Samples were analyzed for salmonellae. Isolated salmonellae were biochemically and serologically identified and tested for antibiotic susceptibility and resistance transfer ability. Salmonellae were recovered from swine at seven of the nine slaughter plants and 16 of the 27 composites of slaughter swine. Of the 19 production units, 3 had swine shedding salmonellae. Resistances found included streptomycin, tetracycline, and sulfadiazine. Of the 52 total isolates tested, 71% had some level of antibiotic resistance. Only 3 of 37 resistant isolated could transfer resistance under the conditions used.
Inactivation of coxsackieviruses B3 and B5 in water by chlorine
Authors: Jensen H , Thomas K , Sharp D G
Published: January 2020

The inactivation rates of coxsackievirus B3 (CB3) and B5 (CB5) by chlorine in dilute buffer at pH 6 were very nearly the same and about half that of poliovirus (Mahoney) under similar conditions. Purified CB3, like the poliovirus, aggregated in the acid range but not at pH 7 and above. Purified CB5 aggregated rapidly at all pH values; still, the graph of log surviving infectivity versus time was a straight line. No chlorine inactivation data were obtained with dispersed CB5, for it could be dispersed only by addition of diethylaminoethyl dextran, which would react with the chlorine. Addition of 0.1 M NaCl to the buffer at pH 6 did not influence the aggregation of CB5 or the rate of chlorine action on either of the coxsackie-viruses, but at pH 10 it increased the disinfection activity of OCl- for both viruses roughly 20-fold. Cesium chloride had a similar but smaller effect. KCl was the most active of the three in this respect, making the inactivating effect of OCl- at pH 10 about equal to that of HOCl at pH 6.
Intestinl fragility during ochratoxicosis and aflatoxicosis in broiler chickens
Authors: Warren M F , Hamilton P B
Published: January 2020

Graded concentrations of dietary ochratoxin (0, 0.5, 1.0, 2.0, 4.0, and 8.0 microgram/g) and aflatoxin (0, 0.625, 1.25, 2.5, 5.0, and 10.0 microgram/g) were fed to broiler chicks from hatching to 3 weeks of age. The breaking strength of the large intestines was decreased significantly (P < 0.05) by ochratoxin (2, 4, and 8 microgram/g), but not by aflatoxin. This fragility was accompanied by an increase in the weight of the large intestine relative to body weight of birds fed ochratoxin (4.0 and 8.0 microgram/g), whereas aflatoxin had no significant (P < 0.05) effect on this parameter. Lipid content of the large intestine was decreased significantly (P < 0.05) by aflatoxin (10.0 microgram/g) and increased by ochratoxin (8.0 microgram/g). Microscopic examination of cross sections of large intestines stained for collagen gave the impression of a great decrease in collagen content of birds fed ochratoxin, but not aflatoxin. The radial length of the collagenous longitudinal folds of the large intestine was decreased significantly (P < 0.05) by ochratoxin (2.0, 4.0, and 8.0 microgram/g). These observations, plus a field case characterized by intestinal ruptures causing carcass condemnations on the processing line and by the occurrence of aflatoxin and ochratoxin in the chicken feed, suggest a novel way in which mycotoxins cause economic loss to agriculture.
Physiological Changes Within a Metalimnetic Layer of
Oscillatoria rubescens
Authors: Konopka Allan
Published: January 2020

Different depths within a metalimnetic layer of
Oscillatoria rubescens
were sampled, and changes in biochemical composition and photosynthetic rate were analyzed. Although differences in pigment and protein content were found, the photosynthetic rates of the samples were not significantly different.
Influence of Cadmium, Zinc, and Lead on Growth, Trap Formation, and Collagenase Activity of Nematode-Trapping Fungi
Authors: Rosenzweig W. D. , Pramer D.
Published: January 2020

Growth and morphogenesis of seven species of nematode-trapping fungi and the activity of a collagenase produced by
Arthrobotrys amerospora
were measured in the presence of various concentrations of divalent cadmium, zinc, or lead. In general, growth varied with species and was dependent on the metal present and the concentration at which it was tested. Cadmium was found to exhibit the greatest toxicity followed by zinc and lead, respectively. In most cases, inhibition of growth was directly correlated with a decreased capacity to form traps. However, in a few cases, trap formation was inhibited either more or less than was growth. The activity of the collagenase was less sensitive than was growth or trap formation to heavy-metal inhibition.
Classification of bacteria from commercial egg washers and washed and unwashed eggs
Authors: Moats W A
Published: January 2020

A total of 432 bacterial isolates from washed and unwashed eggs, egg-washer surfaces, and washwaters from five egg-grading plants in Maryland and southeastern Pennsylvania were classified. Counts on equipment surfaces showed considerable variation from plant to plant, reflecting care used in cleaning. Unwashed eggs had a higher percentage of gram-positive cocci (71%), and isolates included Streptococcus faecalis, Aerococcus, and Escherichia coli, which were not isolated from equipment surfaces and washwaters. Equipment surfaces had a higher proportion of actinomycetes than unwashed eggs, and predominant gram-negative rods were Alcaligenes and Moraxella, which were not found on unwashed eggs. Flavobacterium and Alcaligenes have been implicated in shell egg rots, Staphylococcus aureus has been implicated in food poisoning, and organisms resembling micrococci and actinomycetes have been found in broken-out egg products.
Heat resistance of Desulfotomaculum nigrificans spores in soy protein infant formula preparations
Authors: Donnelly L S , Busta F F
Published: January 2020

The heat resistance of Desulfotomaculum nigrificans spores was determined in soy protein infant formula preparations. Methods of sporulation were developed and evaluated. D. nigrificans spores of highest heat resistance were produced in a 40% infusion of spent mushroom compost. Fraction-negative D121 degrees C-values obtained in modified soy formula were 25.8 min for spores of ATCC 7946 produced at 55 degrees C and 54.4 min for an isolate designated RGI 1, which was sporulated at 66 degrees C. From the fraction-negative D-values, z-values were obtained of 6.7 degrees C for ATCC 7946 and 9.5 degrees C for RGI 1. Survivor-curve D121 degrees C-values were 5.6 min for ATCC 7946 and 2.7 min for RGI 1 sporulated at 55 degrees C and heated in modified soy formula. Corresponding D121 degrees C-values in Butterfield phosphate buffer (pH 7.2) were 3.3 min (ATCC 7946) and 1.1 min (RGI 1). The z-values generated from survivor-curve D-values were similar to those obtained by using fraction-negative procedures. In all instances the inactivation kinetics appeared to be linear. The isolate designated RGI 1, when sporulated at 66 degrees C and heated in a modified infant soy formula, exhibited an extraordinary heat resistance far in excess of previous reports.
Effects of Adaptation on Biodegradation Rates in Sediment/Water Cores from Estuarine and Freshwater Environments
Authors: Spain Jim C. , Pritchard P. H. , Bourquin A. W.
Published: January 2020

Experiments were devised to determine whether exposure to xenobiotics would cause microbial populations to degrade the compounds more rapidly during subsequent exposures. Studies were done with water/sediment systems (ecocores) taken from a salt marsh and a river. Systems were tested for adaptation to the model compounds methyl parathion and
p
-nitrophenol.
14
CO
2
released from radioactive parent compounds was used as a measure of mineralization. River populations preexposed to
p
-nitrophenol at concentrations as low as 60 μg/liter degraded the nitrophenol much faster than did control populations. River populations preexposed to methyl parathion also adapted to degrade the pesticide more rapidly, but higher concentrations were required. Salt marsh populations did not adapt to degrade methyl parathion.
p
-Nitrophenol-degrading bacteria were isolated from river samples but not from salt marsh samples. Numbers of nitrophenol-degrading bacteria increased 4 to 5 orders of magnitude during adaptation. Results indicate that the ability of populations to adapt depends on the presence of specific microorganisms. Biodegradation rates in laboratory systems can be affected by concentration and prior exposure; therefore, adaptation must be considered when such systems are used to predict the fate of xenobiotics in the environment.
Microbiological quality of frozen shrimp and lobster tail in the retail market
Authors: Swartzentruber A , Schwab A H , Duran A P , Wentz B A , Read R B
Published: January 2020

The microbiological quality of three frozen shrimp products and frozen lobster tail at the retail level was determined. The number of retail units of the four products examined and the geometric means for aerobic plate counts at 30 and 35 degrees C, respectively, were: 1,464 units of cooked, peeled shrimp--13,000 and 7,200 per g; 1,468 units of raw, peeled shrimp--860,000 and 300,000 per g; 1,300 units of raw, in-shell shrimp--800,000 and 300,000 per g; 1,315 units of lobster tail--140,000 and 42,000 per g. Geometric means for coliform, Escherichia coli, and Staphylococcus aureus counts for all products were < 10 per g.
Survival of two enterobacteria in feces buried in soil under field conditions
Authors: Temple K L , Camper A K , McFeters G A
Published: January 2020

Feces samples, inoculated with 10(6) Escherichia coli resistant to streptomycin and nalidixic acid and with 10(5) Salmonella typhimurium per g, were buried at five mountain field sites ranging from 2,005 to 2,730 m in elevation. Counts of each bacterium rose initially and then declined to 10(3) or 10(4) per g of feces in 8 weeks. The survival pattern was similar at all sites regardless of marked differences in elevation, soil, moisture, exposure, and vegetation. S. typhimurium numbers were consistently higher than E. coli numbers after week 3. The test encompassed most of the time that the area is snow-free and accessible for hiking. The results were judged to discredit the recommendation for shallow burial of feces and to indicate a potential health hazard under intensive use.
Characteristics of anaerobic oxalate-degrading enrichment cultures from the rumen
Authors: Dawson K A , Allison M J , Hartman P A
Published: January 2020

Enrichment cultures of rumen bacteria degraded oxalate within 3 to 7 days in a medium containing 10% rumen fluid and an initial level of 45 mM sodium oxalate. This capability was maintained in serially transferred cultures. One mole of methane was produced per 3.8 mol of oxalate degraded. Molecular hydrogen and formate inhibited oxalate degradation but not methanogenesis; benzyl viologen and chloroform inhibited both oxalate degradation and methanogenesis. Attempts to isolate oxalate-degrading bacteria from these cultures were not successful. Oxalate degradation was uncoupled from methane production when enrichments were grown in continuous culture at dilution rates greater than or equal to 0.078 h-1. Growth of the uncoupled population (lacking methanogens) in batch culture was accompanied by degradation of 45 mM oxalate within 24 h and production of 0.93 mol of formate per mol of oxalate degraded. Oxalate degradation by the uncoupled population was not inhibited by molecular hydrogen or formate. Cell yields (grams [dry weight]) per mole of oxalate degraded by the primary enrichment and the uncoupled populations were 1.7 and 1.0, respectively.
Abnormal concentrations of B vitamins and amino acids in plasma, bile, and liver of chicks with aflatoxicosis
Authors: Voigt M N , Wyatt R D , Ayres J C , Koehler P E
Published: January 2020

Graded levels of aflatoxin fed to broiler chickens for 3 weeks decreased the levels of most B vitamins in plasma, bile, and liver and decreased all free and hydrolyzed amino acids from peptides in plasma. The levels of thiamine, riboflavin, vitamin B6, pantothenic acid, and choline decreased by more than 60% in bile; vitamin B6, pantothenic acid, and choline decreased by more than 49% in plasma; thiamine, vitamin B6, pantothenic acid, choline, folate, and niacin decreased by more than 19% in liver; and only bile and plasma levels of folate increased (78 and 12%, respectively) with a dietary level of 5 microgram of aflatoxin per g of feed. Plasma levels of cystine and cysteine, methionine, threonine, serine, and aspartic acid decreased by more than 37%, whereas valine, lysine, leucine, histidine, hydroxyproline, and alanine decreased by more than 9% with 2.5 microgram of aflatoxin per g of feed. The data suggest that aflatoxin interferes with the metabolism of B vitamins and amino acids in chicks. However, these changes may be measuring the effects of aflatoxin-induced hepatic necrosis.
Proficiency test sample media for single and mixed pure cultures of water pollution indicator bacteria
Authors: Toombs R W , Connor D A
Published: January 2020

Two transport media, NYSDH-1 and NYSDH-2, were developed for use in a split bacteriological water sample program. The media maintained 88% viability of inoculated organisms for at least 48 h, and the samples do not require special handling or reconstitution. Procedures for preparing and shipping the samples to participating laboratories were developed. A reference set of samples was analyzed in laboratories certified by either New York State or the Environmental Protection Agency. A statistical analysis was performed, and the results indicate that the media are suitable for integration into a laboratory quality control program.
Coliforms in aerosols generated by a municipal solid waste recovery system
Authors: Lembke L L , Kniseley R N
Published: January 2020

Airborne total and fecal coliform concentrations averaged 2.1 X 10(3) and 9.9 X 10(2)/m3, respectively, inside an operating solid waste recovery system. Installation of dust control equipment reduced these levels by 50%. Frequency of recovery of coliforms also dropped by 15%.
Bacterial Degradation of Dichloromethane
Authors: Brunner Walter , Staub Doris , Leisinger Thomas
Published: January 2020

Strain DM1, a facultative methylotrophic bacterium utilizing methanol, formate, mono-, di-, and trimethylamine, as well as dichloromethane as C1 substrates was isolated as an airborne contaminant. The organism is a strictly aerobic, gram-negative, oxidase-positive short rod, motile by a single lateral flagellum. Enzyme assays in crude extracts suggested that it assimilates C1 compounds by the serine/isocitrate lyase-negative pathway. Experiments with extended cultures demonstrated that dichloromethane is a growth-inhibitory substrate. The maximum specific growth rate of 0.11 h
−1
was reached between 2 and 5 mM dichloromethane. The release of Cl
−1
from dichloromethane paralleled growth in extended and continuous cultures. Molar growth yields on methanol and on dichloromethane were 18.6 and 15.7 g/mol, respectively. Since attempts to demonstrate dehalogenation of dichloromethane by crude extracts failed, a dehalogenation assay with resting cells was developed. Maximum dehalogenating activity of cell suspensions was at pH 9.0. The reaction was partially and reversibly inhibited by anaerobiosis. During a shift of a chemostat culture from methanol to dichloromethane as the carbon source, the dehalogenating activity of resting cells was increased at least 500-fold.
Growth of Enterobacter cloacae in the presence of 25% sodium dodecyl sulfate
Authors: Kramer V C , Calabrese D M , Nickerson K W
Published: January 2020

The growth of Enterobacter cloacae in 25% sodium dodecyl sulfate is described. The bacteria appeared to tolerate sodium dodecyl sulfate rather than metabolize it. The process was energy dependent, and cell lysis occurred during stationary phase. Extreme detergent resistance may be characteristic of the genus Enterobacter.