bluuebunny/crossref_metadata_2025 huggingface dataset:
Microbial Oxidation of Gaseous Hydrocarbons: Production of Methyl Ketones from Their Corresponding Secondary Alcohols by Methane- and Methanol-Grown Microbes
Authors: Hou Ching T. , Patel Ramesh , Laskin Allen I. , Barnabe Nancy , Marczak Irene
Published: January 2020

Cultures of methane- or methanol-utilizing microbes, including obligate (both types I and II) and facultative methylotrophic bacteria, obligate methanol utilizers, and methanol-grown yeasts were isolated from lake water of Warinanco Park, Linden, N.J., and lake and soil samples of Bayway Refinery, Linden, N.J. Resting-cell suspensions of these, and of other known C1-utilizing microbes, oxidized secondary alcohols to their corresponding methyl ketones. The product methyl ketones accumulated extracellularly. Succinate-grown cells of facultative methylotrophs did not oxidize secondary alcohols. Among the secondary alcohols, 2-butanol was oxidized at the highest rate. The optimal conditions for in vivo methyl ketone formation were compared among five different types of C1-utilizing microbes. Some enzymatic degradation of 2-butanone was observed. The product, 2-butanone, did not inhibit the oxidation of 2-butanol. The rate of the 2-butanone production was linear for the first 4 h of incubation for all five cultures tested. A yeast culture had the highest production rate. The optimum temperature for the production of 2-butanone was 35°C for all the bacteria tested. The yeast culture had a higher temperature optimum (40°C), and there was a reasonably high 2-butanone production rate even at 45°C. Metal-chelating agents inhibit the production of 2-butanone, suggesting the involvement of metal(s) in the oxidation of secondary alcohols. Secondary alcohol dehydrogenase activity was found in the cell-free soluble extract of sonically disrupted cells. The cell-free system requires a cofactor, specifically nicotinamide adenine dinucleotide, for its activity. This is the first report of a nicotinamide adenine dinucleotide-dependent, secondary alcohol-specific enzyme.
Improved Enumeration of Lactic Acid Streptococci on Elliker Agar Containing Phosphate
Authors: Barach Jeffrey T.
Published: January 2020

Enumeration of lactic acid streptococci from dairy starter cultures on Elliker agar was improved by the addition of 0.4% (wt/vol) diammonium phosphate. Agar plate counts were up to 7.75 times greater due to improved buffering by the phosphate salt.
Development of Defined, Minimal, and Complete Media for the Growth of
Hyphomicrobium neptunium
Authors: Havenner Jeffrey A. , McCardell Barbara A. , Weiner Ronald M.
Published: January 2020

A complete synthetic medium containing 15 amino acids, a minimal synthetic medium (GAMS) containing 4 amino acids, and a supplemented minimal medium (GAMS + calcium pantothenate) have been developed for the cultivation of
Hyphomicrobium neptunium
ATCC 15444. Depending on the complexity of the synthetic media, generation times were approximately 2 to 3 times longer, and maximum cell densities were 0.3 to 0.9 log
10
lower than in ZoBell marine broth 2216. The fates of
14
C-labeled amino acids in GAMS were monitored. Results suggested that
H. neptunium
was auxotrophic for methionine, utilized glutamic acid as a primary energy source, and readily anabolized and catabolized serine and aspartic acid. Individual amino acid concentrations above 125 mM induced prolonged lag periods, whereas only methionine was not growth limiting at a concentration as low as 2 mM.
Distribution of Aerobic Bacteria Which Contain Bacteriochlorophyll
a
Authors: Shiba Tsuneo , Simidu Usio , Taga Nobuo
Published: January 2020

Sixteen strains of aerobic bacteria which contain bacteriochlorophyll
a
were isolated from the samples collected in aerobic marine environments: thalli of
Enteromorpha linza, Porphyra
sp.,
Sargussum horneri
; beach sand; and the surface seawater from Aburatsubo Inlet. When they occurred, their proportions among the aerobic heterotrophic populations ranged from 0.9 to 1.1% in the seaweed samples and from 1.2 to 6.3% in the beach sand samples and were 0.9% in the seawater sample. The results suggested that the aerobic photopigmented bacteria widely inhabit aerobic marine environments.
Anaerobic Biodegradation of Eleven Aromatic Compounds to Methane
Authors: Healy J. B. , Young L. Y.
Published: January 2020

A range of 11 simple aromatic lignin derivatives are biodegradable to methane and carbon dioxide under strict anaerobic conditions. A serum-bottle modification of the Hungate technique for growing anaerobes was used for methanogenic enrichments on vanillin, vanillic acid, ferulic acid, cinnamic acid, benzoic acid, catechol, protocatechuic acid, phenol,
p
-hydroxybenzoic acid, syringic acid, and syringaldehyde. Microbial populations acclimated to a particular aromatic substrate can be simultaneously acclimated to other selected aromatic substrates. Carbon balance measurements made on vanillic and ferulic acids indicate that the aromatic ring was cleaved and that the amount of methane produced from these substrates closely agrees with calculated stoichiometric values. These data suggest that more than half of the organic carbon of these aromatic compounds potentially can be converted to methane gas and that this type of methanogenic conversion of simple aromatics may not be uncommon.
Influence of pH, salinity, and organic matter on the adsorption of enteric viruses to estuarine sediment
Authors: LaBelle R L , Gerba C P
Published: January 2020

This study was designed to determine the degree of adsorption of enteric viruses to marine sediment and factors controlling this association. Adsorption and elution characteristics of several enteroviruses and one rotavirus to estuarine sediments were studied under varying conditions of pH, salinity, and presence of soluble organics. Greater than 99% of the added poliovirus type 1 (LSc), coxsackievirus type B3 (Nancy), echovirus type 7 (Wallace), and rotavirus (SA-11) adsorbed to sediment. Echovirus 1 (Farouk) and a recent isolate typed as coxsackievirus B4 adsorbed significantly less than poliovirus 1 under similar conditions of varying salinity and pH. The presence of soluble organic matter, in the form of secondary sewage effluent or humic acid, did not affect these patterns of adsorption. Only echovirus 1 (Farouk) desorbed when the pH or salinity was altered and then only to a small extent. Three recent isolates of echovirus 1 and echovirus 29 (strain JV-10) also demonstrated varying amounts of adsorption to sediment. These data indicate that enteric viruses can become readily associated with sediment in the estuarine environment and that this association may play a major role in their hydrotransportation and survival.
Oxidation of secondary alcohols to methyl ketones by yeasts
Authors: Patel R N , Hou C T , Laskin A I , Derelanko P , Felix A
Published: January 2020

Cell suspensions of yeasts, Candida utilis ATCC 26387, Hansenula polymorpha ATCC 26012, Pichia sp. NRRL-Y-11328, Torulopsis sp. strain A1, and Kloeckera sp. strain A2, grown on various C-1 compounds (methanol, methylamine, methylformate), ethanol, and propylamine catalyzed the oxidation of secondary alcohols to the corresponding methyl ketones. Thus, isopropanol, 2-butanol, 2-pentanol, and 2-hexanol were converted to acetone, 2-butanone, 2-pentanone, and 2-hexanone, respectively. Cell-free extracts derived from methanol-grown yeasts catalyzed an oxidized nicotinamide adenine dinucleotide-dependent oxidation of secondary alcohols to the corresponding methyl ketones, Primary alcohols were not oxidized. The effect of various environmental factors on the production of methyl ketones from secondary alcohols by methanol-grown Pichia sp. was investigated.
Comparative adsorption of human enteroviruses, simian rotavirus, and selected bacteriophages to soils
Authors: Goyal S M , Gerba C P
Published: January 2020

Virus adsorption to soils is considered to be the most important factor in removing viruses after land treatment of wastewater. Most of the studies on virus adsorption to soils have utilized poliovirus as the model system. In the present study, comparative adsorption of a number of different types and strains of human enteroviruses and bacteriophages to nine different soil types was studied. Under the experimental conditions of this study, greater than 90% of all viruses adsorbed to a sandy loam soil except echovirus types 1, 12, and 29 and a simian rotavirus (SA-11), which adsorbed to a considerably lower degree. A great deal of variability was observed between adsorption of different strains of echovirus type 1, indicating that viral adsorption to soils is highly strain dependent. Of the five phages studied, f2 and phi X174 adsorbed the least. In addition to being dependent on type and strain of virus, adsorption was found to be influenced also by type of soil. Thus, soils having a saturated pH of less than 5 were generally good adsorbers. From these results, it appears that no one enterovirus or coliphage can be used as the sole model for determining the adsorptive behavior of viruses to soils and that no single soil can be used as the model for determining viral adsorptive capacity of all soil types.
Comparison of antibodies in marine fish from clean and polluted waters of the New York Bight: relative levels against 36 bacteria
Authors: Robohm R A , Brown C , Murchelano R A
Published: January 2020

Fish from polluted waters are subject to increased prevalence of disease. Because they respond to bacterial pathogens by producing serum antibodies, it was possible to construct a seasonal serological record in three fish species from clean and polluted waters of the New York Bight. Antibody levels were determined by testing sera for agglutinating activity against 36 strains of bacteria. Evaluation of 5,100 antibody titrations showed the following. During warm months, summer flounder (Paralichthys dentatus) from the polluted area had significantly higher antibody levels and antibody to a greater diversity of bacteria than fish from the unpolluted area. Weakfish (Cynoscion regalis) from the same polluted area shared with summer flounder raised titers to many bacteria. The greatest proportion of raised titers was against Vibrio species, although prominent titers were also seen against Aeromonas salmonicida and Haemophilus piscium, bacteria usually associated with diseases in freshwater but not marine fish. Differences between polluted and clean waters were not as evident in winter flounder (Pseudopleuronectes americanus) during cold months. This could be due, in part, to reduced antibody production at colder temperatures. The data illustrate the usefulness of the serum antibody record in identifying environmental exposure to bacteria in marine fish and indicate that the polluted New York Bight apex has increased levels and diversity of bacteria during warm months.
Effect of chlorine substitution on the bacterial metabolism of various polychlorinated biphenyls
Authors: Furukawa K , Tomizuka N , Kamibayashi A
Published: January 2020

Of 36 pure isomers (chlorine numbers 1 to 5) of polychlorinated biphenyls examined, 23 compounds were metabolized by Alcaligenes sp. strain Y42, and 33 compounds were metabolized by Acinetobacter sp. strain P6. The major pathway of many polychlorinated biphenyl isomers examined was considered to proceed through 2',3'-dihydro-2',3'-diol compounds, concomitant dehydrogenated 2',3'-dihydroxy compounds, subsequently the 1',2'-meta-cleavage compounds (chlorinated derivatives of 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acids), and then chlorobenzoic acids. The meta-cleavage products were usually converted to chlorobenzoic acids upon further incubation in many polychlorinated biphenyls, but they accumulated specifically in the metabolism of 2,4'-, 2,4,4'-, and 2,5,4'-chlorobiphenyls, which are all chlorinated at the 2,4'-position in the molecules in common. Dihydroxy compounds accumulated mainly in the metabolism of 2,6-, 2,3,6-, 2,4,2',5'-, 2,5,2',5'-, and 2,4,5,2',5'-chlorobiphenyls by Acinetobacter sp. P6. The 2,3,2',3'-, 2,3,2',5'-, and 2,4,5,2',3'-chlorobiphenyls, which are chlorinated at the 2,3-position of one of the rings, were metabolized in a different fashion. Two major metabolites of a chlorobenzoic acid and an unknown compound accumulated always in the metabolism of this group of polychlorinated biphenyls. 2,4,6-Trichlorobiphenyl was metabolized quite differently between the two organisms. Alcaligenes sp. Y42 metabolized this compound very slowly to trichlorobenzoic acid by the major oxidative route. In contrast, Acinetobacter sp. P6 metabolized it to a trihydroxy compound via a dihydroxy compound.
Production of
S
-Methylthioacetate by
Brevibacterium linens
Authors: Cuer A. , Dauphin G. , Kergomard A. , Dumont J. P. , Adda J.
Published: January 2020

Volatile sulfur compounds production by eight strains of
Brevibacterium linens
isolated from cheeses was demonstrated: methanethiol, dimethyldisulfide, and 2,3,4-trithiapentane. Four of these strains also produced
S
-methylthioacetate, an important aroma component of smear-coated cheeses. It is the first demonstrated microbiological production of a thioester.
Acceptance by swine and rats of corn amended with trichothecenes
Authors: Vesonder R F , Ciegler A , Burmeister H R , Jensen A H
Published: January 2020

Swine and rats demonstrated the same response factor (i.e., the average amount of corn amended with trichothecenes consumed by animals per the average amount of uncontaminated corn consumed by animals) for consumption of corn amended with 40 ppm of either T-2 toxin or diacetoxyscirpenol Rat response factor for corn containing 40 ppm of vomitoxin was 1.8 times more than corn containing either T-2 toxin or diacetoxyscirpenol at 40 ppm. For the corn containing 40 ppm of vomitoxin, swine response factor was 1.8 times greater than rat response factor.
Efficiency of several micro-fiber glass filters for recovery of poliovirus from tape water
Authors: Payment P , Trudel M
Published: January 2020

Micro-fiber glass filters from Gelman, Filterite, Johns-Manville, and Whatman were compared with Millipore membrane filters on the basis of their virus adsorbancy, flow rate, clogging resistance, and virus concentration efficiency by using tap water at 2 nephelometric turbidity units. As virus adsorbants the Johns-Manville D39, Filterite 0.25-micron, Filterite 0.45-micron, and Millipore 0.45-micron filters were the most efficient, retaining more than 99% of the added virus in water at pH 3.5 and 0.0005 M aluminum chloride. The Johns-Manville D79 and D49 filters retained 92 and 96% of the virus, respectively, whereas the Whatman GF-D, Whatman GF-F, Gelman A-E, and Millipore AP-20 filters retained only 28, 78, 56, and 34% of the virus, respectively. The best flow rate and clogging resistance were obtained with the Johns-Manville D79 filter or with this filter acting as a prefilter to the Johns-Manville D49, Johns-Manville D39, or Filterite 0.45-micron filter. Finally, poliovirus experimentally seeded in 20 liters of tape water was recovered from Johns-Manville D79-Johns-Manville D39 or Johns-Manville D79-Filterite 0.45 micron 142-mm filter combinations was a efficiencies of 86 and 85%, respectively.
Viral aggregation: buffer effects in the aggregation of poliovirus and reovirus at low and high pH
Authors: Floyd R , Sharp D G
Published: January 2020

The effects of the buffer employed in maintaining a given pH value were tested on the aggregation of two viruses, poliovirus and reovirus. Poliovirus was found to aggregate at pH values of 6 and below, but not at pH 7 or above, except in borate buffer. Reovirus aggregated at pH 4 and below, but was found to aggregate only in acetate or tris(hydroxymethyl)aminomethane-citrate buffers at pH 5. Other buffers tested for aggregation of reovirus at pH 5 (succinate, citrate, and phosphate-citrate) induced little aggregation. No significant aggregation was found for reovirus at pH 6 and above. For both viruses, the most effective aggregation was induced by buffers having a substantial monovalently charged anionic component, such as acetate at pH 5 and 6 or citrate at pH 3. Cationic buffers at low pH, such as glycine, were generally weaker in aggregating ability than anionic buffers at the same pH. These results, when correlated with the isoelectric point of the viruses (poliovirus at pH 8.2; reovirus at pH 3.9) indicated that both viruses aggregated strongly when their overall charge was positive, but only under certain circumstances when their overall charge was negative. Although reovirus aggregated massively at its isoelectric point, poliovirus remained dispersed at its isoelectric point. The conclusion can be drawn that those pH and buffer conditions which induced aggregation of one virus do not necessarily induce it in another.
Characteristic gamma-lactone odor production of the genus Pityrosporum
Authors: Labows J N , McGinley K J , Leyden J J , Webster G F
Published: January 2020

Mass spectrometric-gas chromatographic analysis of culture headspaces revealed that members of the genous Pityrosporum produce volatile gamma-lactones during growth on lipid-containing media. Representative members of other yeast genera found on humans failed to produce these compounds. Addition of lecithin, oleic acids, triolein, or human sebum to the culture media stimulated gamma-lactone production by Pityrosporum species. All yeasts tested produced isopentanol and phenylethanol. Production of gamma-lactones may serve as a valuable characteristic in the identification of organisms of the genus Pityrosporum.
Enumeration and Isolation of Lactate-Utilizing Bacteria from the Rumen of Sheep
Authors: Mackie R. I. , Heath Suzette
Published: January 2020

A highly specific medium was developed for the enumeration of lactate-utilizing bacteria in the rumen of sheep. This medium, which contained 2.0% lactate, 2.0% Trypticase, 0.2% yeast extract, and volatile fatty acids, hemin, and trace elements in place of rumen fluid, enabled high counts (42 � 10
7
to 190 � 10
7
/g of ingesta) of lactate-utilizing bacteria to be made with a high degree of specificity (96%). The medium also supported the growth of all species of predominant lactate-utilizing bacteria reported to occur in the rumen and thus is of importance for ecological studies where the incidence and influence of the different species on lactate metabolism under changing conditions in the rumen cannot be predicted. The survival rate of isolates was increased from 60 to 96% by addition to the modified maintenance medium of 40% rumen fluid in place of the volatile fatty acids, hemin, and trace elements used in the counting medium. These results, together with the slow growth of colonies in roll bottles, showed that, although highly selective, the counting medium was not optimal for the types selected.
Changes in Lactate-Producing and Lactate-Utilizing Bacteria in Relation to pH in the Rumen of Sheep During Stepwise Adaptation to a High-Concentrate Diet
Authors: Mackie R. I. , Gilchrist Frances M. C.
Published: January 2020

Changes in the numbers and types of lactate-producing and lactate-utilizing bacteria in the rumen of sheep were followed during stepwise adaptation from a low- to a high-concentrate diet. The mean numbers of bacteria increased after each change in diet when increasing amounts of maize grain were substituted for maize stover. A surge in number of amylolytic bacteria always preceded an increase in lactate-utilizing bacteria, and with the final diet containing 71% grain and molasses the two groups tended to balance each other, which resulted in low lactic acid accumulation. The lactate utilizers thus played a key role in controlling the fermentation. Orderly shifts occurred among the predominating amylolytic and lactate-utilizing bacteria in response to the gradual decrease in ruminal pH as the amount of maize meal in the diet increased. Among the lactate utilizers, the succession began with acid-sensitive
Veillonella
and
Selenomonas
, which were superseded by more acid-tolerant
Anaerovibrio
and
Propionibacterium
. Among the amylolytic bacteria,
Bacteroides
was superseded by more acid-tolerant
Lactobacillus
and
Eubacterium
. The ecological succession of predominating genera was shown to be correlated significantly with ruminal pH and, more specifically, with the length of time as well as the extent to which the pH remained below a certain critical undefined value in the rumen, arbitrarily set at pH 6.00.
Production of arsine and methylarsines in soil and in culture
Authors: Cheng C N , Focht D D
Published: January 2020

Arsenate, arsenite, monomethylarsonate, and dimethylarsinate were added to different soils, and evolution of gaseous arsenical products was determined over 3 weeks. Arsine was produced in all three soils from all substrates, whereas methylarsine and dimethylarsine were produced only from methylarsonate and dimethylarsinate, respectively. At least three times more arsine than dimethylarsine was produced in soil incubated with dimethylarsinate. Resting cell suspensions of Pseudomonas and Alcaligenes produced arsine as the sole product when incubated anaerobically in the presence of arsenate or arsenite. In all instances, no trimethylarsine was observed, nor could any evidence be shown for the methylation of any arsenical substrate in soil or in culture. It was concluded that reduction to arsine, not methylation to trimethylarsine, was the primary mechanism for gaseous loss of arsenicals from soil.
Lytic Organisms and Photooxidative Effects: Influence on Blue-Green Algae (Cyanobacteria) in Lake Mendota, Wisconsin
Authors: Fallon R. D. , Brock T. D.
Published: January 2020

The effects of exposure to high light intensities on blue-green algal (cyanobacterial) populations were examined in Lake Mendota, Wis. The algal populations were shown to be susceptible to inhibition of photosynthetic activity and pigment bleaching as a result of exposure. These effects generally influence only a small percentage of the lake population and thus are probably not important in causing major declines in chlorophyll
a
. Lytic organisms were shown to increase in numbers in the lake in response to the seasonal development of blue-green algae, reaching values of greater than 1,000 plaque-forming units per ml in midsummer. Both bacteria and protozoa were observed in plaque zones, but it could not be determined whether these lytic organisms had a major role in algal biomass declines.
Abiotic factors affecting the toxicity of lead to fungi
Authors: Babich H , Stotzky G
Published: January 2020

The toxicity of lead (Pb) to fungi in pure culture was influenced by several abiotic factors: pH, inorganic anions, clay minerals, and particulate (humic acid) and soluble organic matter. The toxicity of Pb was potentiated under acidic conditions (pH 5 and 6), and phosphate or carbonate anions reduced the toxicity, apparently as a result of the formation of sparingly soluble Pb salts. Clay minerals (montmorillonite greater than attapulgite greater than kaolinite) and particulate humic acid protected against the toxicity of Pb, presumably as the result of sorption, by cation exchange of the Pb to the exchange complexes, which reduced its availability for uptake by the fungi. Soluble organics, such as tryptone, yeast extract, cysteine, succinic acid, and increasing concentrations of neopeptone, also reduced the toxicity of Pb.
Effect of mercuric ion on the growth, photosynthesis, and nitrogenase activity of Anabaena inaequalis
Authors: Stratton G W , Huber A L , Corke C T
Published: January 2020

Anabaena inaequalis was sensitive to mercuric ion (Hg2+) in the ppb (nanogram per milliliter) range. Growth was inhibited significantly at concentrations of metal ion as low as 2 ppb, and 100 ppb was required to inhibit photosynthesis and acetylene reduction. Low levels of Hg2+ stimulated acetylene reduction and photosynthesis. The lysis of vegetative cells was the primary action of mercuric ions, resulting in the inhibition of growth, photosynthesis, and nitrogenase activity. There was a linear relationship between numbers of cells and the amount of Hg2+ required to induce culture lysis. Calculated on the basis of equivalent cell numbers, Hg2+ was toxic to A. inaequalis at 0.006, 0.009, and 0.100 micrograms of Hg2+ per 10(5) cells for photosynthesis, growth, and acetylene reduction, respectively.
Biodegradation of polystyrene, poly(metnyl methacrylate), and phenol formaldehyde
Authors: Kaplan D L , Hartenstein R , Sutter J
Published: January 2020

The biodegradation of three synthetic 14C-labeled polymers, poly(methyl methacrylate), phenol formaldehyde, and polystyrene, was studied with 17 species of fungi in axenic cultures, five groups of soil invertebrates, and a variety of mixed microbial communities including sludges, soils, manures, garbages, and decaying plastics. Extremely low decomposition rates were found. The addition of cellulose and mineral failed to increase decomposition rates significantly.
Distribution of membrane-bound monoamine oxidase in bacteria
Authors: Murooka Y , Doi N , Harada T
Published: January 2020

The distribution of membrane-bound monoamine oxidase in 30 strains of various bacteria was studied. Monoamine oxidase was determined by using an ammonia-selective electrode; analyses were sensitive and easy to perform. The enzyme was found in some strains of the family Enterobacteriaceae, such as Klebsiella, Enterobacter, Escherichia, Salmonella, Serratia, and Proteus. Among strains of other families of bacteria tested, only Pseudomonas aeruginosa IFO 3901, Micrococcus luteus IFO 12708, and Brevibacterium ammoniagenes IAM 1641 had monoamine oxidase activity. In all of these bacteria except B. ammoniagenes, monoamine oxidase was induced by tyramine and was highly specific for tyramine, octopamine, dopamine, and norepinephrine. The enzyme in two strains oxidized histamine or benzylamine. Correlations between the distributions of membrane-bound monoamine oxidase and arylsulfatase synthesized in the presence of tyramine were discussed.
Toxin production by Clostridium botulinum type A under various fermentation conditions
Authors: Siegel L S , Metzger J F
Published: January 2020

The time of appearance and the quantity of toxin produced by the Hall strain of Clostridium botulinum type A were examined under various conditions. A 70-liter fermentor and a complex medium consisting of 2% casein hydrolysate and 1% yeast extract plus an appropriate concentration of glucose were employed. Optimal conditions for toxin production were as follows: a nitrogen overlay at a rate of 5 liters/min, an agitation rate of 50 rpm, a temperature of 35 degrees C, and an initial glucose concentration of 1.0% with the pH uncontrolled. Under these conditions, the maximum toxin concentration (6.3 x 10(5) mouse median lethal doses/ml) was attained within 24 h. Cell lysis was apparently not required to obtain maximum toxin concentrations under the fermentation conditions described.
Purification and Some Properties of an Extracellular Amylase from a Moderate Halophile,
Micrococcus halobius
Authors: Onishi Hiroshi , Sonoda Koji
Published: January 2020

A moderate halophile,
Micrococcus halobius
ATCC 21727, produced an extracellular dextrinogenic amylase when cultivated in media containing 1 to 3 M NaCl. The amylase was purified from the culture filtrate to an electrophoretically homogenous state by glycogen-complex formation, diethylaminoethyl-cellulose chromatography, and Bio-Gel P-200 gel filtration. The enzyme had maximal activity at pH 6 to 7 in 0.25 M NaCl or 0.75 M KCl at 50 to 55°C. The activity was lost by dialysis against distilled water. Molecular weight was estimated to be 89,000 by sodium dodecyl sulfate-gel electrophoresis. The action pattern on amylose, soluble starch, and glycogen showed that the products were maltose, maltotriose, and maltotetraose, with lesser amount of glucose.
Effect of Inoculation with N
2
-Fixing Spirilla and
Azotobacter
on Nitrogenase Activity on Roots of Maize Grown Under Subtropical Conditions
Authors: Hegazi N. A. , Monib M. , Vlassak K.
Published: January 2020

Inoculated and non-inoculated seedlings of maize were grown in fertile clayloam soils of Egypt and Belgium under subtropical conditions provided in a greenhouse. Acetylene-reducing activity and microbial counts were determined during a period ranging from 6 to 12 weeks after sowing. Irrespective of soil origin, N
2
-fixing spirilla and
Azotobacter
were common under maize cultivation. Inoculation resulted in a transitional increase in their numbers at early stages of growth. Nitrogenase activity was not detected in the rhizosphere of young plants. The maximum activities measured (81 to 1,436 nmol of C
2
H
4
g
−1
h
−1
) occurred close to the 50 to 70% silking stage. Inoculation with N
2
-fixing spirilla, particularly in Nile Delta soil, doubled the amount of N
2
fixed in a late period of growth (12 weeks), whereas inoculation with
Azotobacter
had no noticeable effect.
Evidence for more than one division of bacteria within airborne particles
Authors: Dimmick R L , Wolochow H , Chatigny M A
Published: January 2020

When the protocol that we had used to demonstrate a single division of bacterial cells in airborne particles was changed to one that increased the glycerol content of the atomizer fluid from 1 to 5% (vol/vol), thus producing larger particles, more than two (and nearly three) divisions of bacteria occurred within 6 h of aerosol time.
14C-most-probable-number method for enumeration of active heterotrophic microorganisms in natural waters
Authors: Lehmicke L G , Williams R T , Crawford R L
Published: January 2020

A most-probable-number method using 14C-labeled substrates is described for the enumeration of aquatic populations of heterotrophic microorganisms. Natural populations of microorganisms are inoculated into dilution replicates prepared from the natural water from which the organisms originated. The natural water is supplemented with a 14C-labeled compound added so as to approximate a true environmental concentration. 14CO2 evolved by individual replicates is trapped in NaOH and counted by liquid scintillation techniques for use in scoring replicates as positive or negative. Positives (14CO2 evolution) are easily distinguished from negatives (no 14CO2 evolution). The results from a variety of environments using the 14CO2 procedure agreed well with previously described methods, in most instances. The 14C-most-probable-number method described here reduces handling procedures over previously described most-probable-number procedures using 14C-labeled substrates. It also appears to have advantages over other enumeration methods in its attempt to approximate natural conditions more closely.
Bacterial flora of the schistosome vector snail Biomphalaria glabrata
Authors: Ducklow H W , Boyle P J , Maugel P W , Strong C , Mitchell R
Published: January 2020

The aerobic heterotrophic bacterial flora in over 200 individuals from 10 wild populations and 3 laboratory colonies of the schistosome vector snail Biomphalaria glabrata was examined. Internal bacterial densities were inversely proportional to snail size and were higher in stressed and laboratory-reared snails. The numerically predominant bacterial genera in individual snails included Pseudomonas, Acinetobacter, Aeromonas, Vibrio, and several members of the Enterobacteriaceae. Enterobacteriaceae seldom predominated in laboratory colonies. Our data suggest that Vibrio extorquens and a Pasteurella sp. tend to predominate in high-bacterial-density snails. These snails may be compromised and may harbor opportunistic snail pathogens.
Microbial growth on hydrocarbons: terminal branching inhibits biodegradation
Authors: Schaeffer T L , Cantwell S G , Brown J L , Watt D S , Fall R R
Published: January 2020

A variety of octane-utilizing bacteria and fungi were screened for growth on some terminally branched dimethyloctane derivatives to explore the effects of iso- and anteiso-termini on the biodegradability of such hydrocarbons. Of 27 microbial strains tested, only 9 were found to use any of the branched hydrocarbons tested as a sole carbon source, and then only those hydrocarbons containing at least one iso-terminus were susceptible to degradation. Anteiso-or isopropenyl termini prevented biodegradation. None of the hydrocarbonoclastic yeasts tested was able to utilize branched-hydrocarbon growth sustrates. In the case of pseudomonads containing the OCT plasmid, whole-cell oxidation of n-octane was poorly induced by terminally branched dimethyloctanes. In the presence of a gratuitous inducer of the octane-oxidizing enzymes, the iso-branched 2,7-dimethyloctane was slowly oxidized by whole cells, whereas the anteiso-branched 3,6-dimethyloctane was not oxidized at all. This microbial sampling dramatically illustrated the deleterious effect of alkyl branching, especially anteiso-terminal branching, on the biodegradation of hydrocarbons.
Incidence of zearalenol (Fusarium mycotoxin) in animal feed
Authors: Mirocha C J , Schauerhamer B , Christensen C M , Niku-Paavola M L , Nummi M
Published: January 2020

Zearalenol, the reduction product of zearalenone produced by Fusarium roseum growing in cereals, was found for the first time naturally occurring in oats and corn. This metabolite is three to four times more active estrogenically than zearalenone.
Phosphate uptake in Saccharomyces cerevisiae Hansen wild type and phenotypes exposed to space flight irradiation
Authors: Berry D , Volz P A
Published: January 2020

Rates of phosphate uptake were approximately twice as great for Saccharomyces cerevisiae single-cell phenotypic isolates exposed to space parameters as for the wild-type ground control. Quantitative determination of 32P was performed by liquid scintillation spectrometry utilizing Cerenkov radiation counting techniques.
Two Improved Methods for Obtaining Axenic Cultures of Cyanobacteria
Authors: Vaara Timo , Vaara Martti , Niemelä Seppo
Published: January 2020

Scoring the agar plate before incubation under unidirectional light led to a rapid separation of gliding filamentous cyanobacteria from their contaminating bacteria. Twenty strains were purified by the method. Additionally, 13 axenic cyanobacterial strains were isolated from pour plates made after treatment of cyanobacterial cultures in tryptone-yeast extract-glucose broth with cycloserine in darkness to select for obligate photoautotrophs.
Apparatus for Monitoring the Mineralization of Volatile
14
C-Labeled Compounds
Authors: Marinucci A. C. , Bartha R.
Published: January 2020

Quantitative mineralization studies on radiolabeled compounds having high vapor pressures need to cope with several technical difficulties. An incubation and trapping system is described that was successfully used in mineralization studies on highly volatile trichlorobenzenes and other xenobiotic pollutants.
Participation of lysine-sensitive aspartokinase in threonine production by S-2-aminoethyl cysteine-resistant mutants of Serratia marcescens
Authors: Komatsubara S , Kisumi M , Chibata I
Published: January 2020

S-2-Aminoethyl cysteine (AEC) reduced both growth rate and final growth level of Serratia marcescens Sr41. The growth inhibition was completely reversed by lysine. AEC inhibited the activity of lysine-sensitive aspartokinase to a lesser extent than lysine. The AEC addition to the medium lowered not only the level of lysine-sensite aspartokinase but also those of homoserine dehydrogenase and threonine deaminase, whereas lysine repressed the aspartokinase alone. To select mutations releasing lysine-sensitive aspartokinase from feedback controls, AEC-resistant colonies were isolated from strains HNr31 and HNr53, both of which were previously found to excrete threonine on the minimal plates but not on the plates containing excess lysine. Two of 280 resistant colonies excreted large amounts of threonine. Strains AECr174 and AECr301, derived from strains HNr31 and HNr53, respectively, lacked both feedback inhibition and repression of lysine-sensitive aspartokinase. These strains produced about 7 mg of threonine per ml in the medium containing glucose and urea.
Cationic composition of 22 species of bacteria grown in seawater medium
Authors: Jones G E , Royle L G , Murray L
Published: January 2020

Twenty-two species of bacteria of marine, estuarine, and terrestrial origin were analyzed for cationic content by atomic absorption spectrophotometry after growth in a basal seawater medium. Alcaligenes marinus was analyzed from eight separate but replicate determinations yielding the following cationic concentrations: Na, 5,600 +/- 2,260; Mg 1,580 +/- 740; K, 700 +/- 360; Ca, 790 +/- 390; Mn, 1.7 +/- 0.5; Fe, 256 +/- 57; Ni, 1.7 +/- 0.7; Cu, 14 +/- 4; Zn, 122 +/- 27; Cd, 2.8 +/- 0.7; and Pb, 10 +/- 3 ppm/(dry weight). Washing A. marinus cells before analyses was necessary due to interstitial medium within the cell pellets after centrifugation and loose cationic retention by the cells. The principal source of error in the procedure was ascribed to variability due to washing cells with 0.5 M ammonium formate. The mean cationic concentrations for trace elements in the 22 bacterial cultures grown in the basal seawater medium to constant optical density and washed three times with 0.5 M ammonium formate were: Mn, 2.4 +/- 3.8; Fe, 262 +/- 112; Ni, 2.3 +/- 1.8; Cu, 24 +/- 17; Zn, 146 +/- 72; Cd, 3.8 +/- 2.5; and Pb, 17 +/- 21 ppm (dry weight). Major ions were concentrated only occasionally by the cells after washing, whereas Mn, Fe, Ni, Cu, Zn, Cd, and Pb were concentrated from the medium by the following factors on the average: 180, 1,600, 140, 1,200, 750, 1,900, and 900, respectively.
Heat inactivation of Mycobacterium avium-Mycobacterium intracellulare complex organisms in aqueous suspension
Authors: Merkal R S , Crawford J A
Published: January 2020

Isolants from swine and from humans representing serotypes 1, 2, 4, 8, and 10 of the Mycobacterium avium-Mycobacterium intracellulare complex were compared for heat tolerance in aqueous suspension. The most heat-resistant isolant found was a serovar 10 isolated from a human. This isolant was examined further to determine the rate of kill at various temperatures and pH's, the effect of meat protein and fat, and the effect of nitrite. Kill rates were not significant at 60 degrees C or below. Decimal reduction values were 4 min or less at 65 degrees C and 1.5 min or less at 70 degrees C. Kill rates were slightly higher at pH values of 6.5 and 7.0 than at 5.5 or 6.0. the water-soluble fraction of wiener emulsion did not alter kill rates, but the saline-soluble fraction protected the organism somewhat. Fat did not affect the survival of the organisms except to eliminate the protective effect of saline extract when the suspension contained 50% fat. The addition of sodium nitrite to the suspension did not alter the heat sensitivity of the organisms.
N-demethylation of nicotine and reduction of nicotine-1'-N-oxide by Microsporum gypseum
Authors: Sindelar R D , Rosazza J P , Barfknecht C F
Published: January 2020

Several microorganisms were examined for their abilities to convert S-nicotine into nornicotine. Five microorganisms including Microsporum gypseum (ATCC 11395) produced nornicotine and three unknown metabolites. M. gypseum efficiently reduced nicotine-1'-N-oxide to nicotine, but no nornicotine was obtained when the N-oxide was used as substrate.
Measurement of Microbial Activity and Growth in the Ocean by Rates of Stable Ribonucleic Acid Synthesis
Authors: Karl David M.
Published: January 2020

A relatively simple and extremely sensitive technique for measuring rates of stable ribonucleic acid (RNA) synthesis was devised and applied to bacterial cultures and seawater samples. The procedure is based upon the uptake and incorporation of exogenous radiolabeled adenine into cellular RNA. To calculate absolute rates of synthesis, measurements of the specific radioactivity of the intracellular adenosine 5′-triphosphate pools (precursor to RNA) and of the total amount of radioactivity incorporated into stable cellular RNA per unit time are required. Since the rate of RNA synthesis is positively correlated with growth rate, measurements of RNA synthesis should be extremely useful for estimating and comparing the productivities of microbial assemblages in nature. Adenosine 5′-triphosphate, adenylate energy charge, and rates of stable RNA synthesis have been measured at a station located in the Columbian Basin of the Caribbean Sea. A subsurface peak in RNA synthesis (and therefore growth) was located within the dissolved oxygen minimum zone (450 m), suggesting in situ microbiological utilization of dissolved molecular oxygen. Calculations of the specific rates of RNA synthesis (i.e., RNA synthesis per unit of biomass) revealed that the middepth maximum corresponded to the highest specific rate of growth (420 pmol of adenine incorporated into RNA·day
−1
) of all depths sampled, including the euphotic zone. The existence of an intermediate depth zone of active microbial growth may be an important site for nutrient regeneration and may serve as a source of reduced carbon for mesopelagic and deep sea environments.
Steady-State Growth and Chemical Composition of the Marine Chlorophyte
Dunaliella tertiolecta
in Nitrogen-Limited Continuous Cultures
Authors: Goldman Joel C. , Peavey Dwight G.
Published: January 2020

The marine chlorophyte
Dunaliella tertiolecta
was grown in continuous cultures under NH
4
+
-N, NO
2
−
-N, NO
3
−
-N, and urea-N limitations. The effect of the nitrogen cell quota (

Q
n

) on the steady-state growth rate (μ) was the same regardless of the N source. The relationship between μ and

Q
n

was well described by the Droop equation, but only up to the true maximum growth rate ^μ (= cell washout rate). The ratio between the minimum cell quota (

k
Q

) and the maximum cell quota (

Q
m

) was 0.19. Hence, there is no substitute for determining ^μ experimentally. That there was no difference in growth response to different N sources suggests that no internal pooling of inorganic nitrogen occurred. Both the carbon (

Q
c

) and phosphorus (

Q
p

) cell quotas under N limitation increased with increasing μ in a threshold fashion: virtually no change in either cell quota up to ∼0.8 ^μ, followed by a rapid and large increase up to ^μ. In addition, in the region of low μ, there was an increase in

Q
p

with a decreasing medium N/P ratio of between 15 and 5 (by atoms). The results generally indicate the physiological limits in cellular constituency under N limitation. The usefulness of this information, however, in describing the response of natural populations of marine phytoplankton to transient nutrient exposures on the temporal and spatial microscales that most likely exist is of limited value.
Alkaline Phosphatase Assay for Freshwater Sediments: Application to Perturbed Sediment Systems
Authors: Sayler Gary S. , Puziss Marla , Silver Martin
Published: January 2020

The
p
-nitrophenyl phosphate hydrolysis-phosphatase assay was modified for use in freshwater sediment. Laboratory studies indicated that the recovery of purified alkaline phosphatase activity was 100% efficient in sterile freshwater sediments when optimized incubation and sonication conditions were used. Field studies of diverse freshwater sediments demonstrated the potential use of this assay for determining stream perturbation. Significant correlations between phosphatase and total viable cell counts, as well as adenosine triphosphate biomass, suggested that alkaline phosphatase activity has utility as an indicator of microbial population density and biomass in freshwater sediments.
Cyclopiazonic acid production by Penicillium camemberti Thom and natural occurrence of this mycotoxin in cheese
Authors: Le Bars J
Published: January 2020

Every Penicillium camemberti strain freshly isolated from 20 commercial cheese brands produced cyclopiazonic acid in two culture media at 25, 13, and 4 degrees C; the toxin yield was greatly dependent on the strain and environmental parameters (medium, temperature, and incubation time). The toxigenic ability appeared as a log-normal distribution. This mycotoxin was found in the crust (0.05 to 0.1 microgram/g in three samples, 0.1 to 0.2 microgram/g in five samples, and 0.4, 1, and 1.5 microgram/g in three other samples) but not in the inner part. When its acute toxicity is considered, doses eventually ingested by consumers are very low (lower than 4 microgram). Means for prevention are discussed. A highly toxigenic strength and rate appear to be necessary features leading to natural contamination in cheeses. The distribution of toxigenic ability makes possible without delay a choice of weakly toxic strains.
Blue light inhibits mycotoxin production and increases total lipids and pigmentation in Alternaria alternata
Authors: Häggblom P , Unestam T
Published: January 2020

Light inhibits production of the mycotoxins alternariol and alternariol monomethyl ether, both polyketids produced by Alternaria alternata. This effect seems to be general because seven isolates of A. alternata with different alternariol- and alternariol monomethyl ether-producing abilities all respond to continuous light with reduced levels of alternariol and alternariol monomethyl ether when the mycotoxins were calculated on a microgram-per-milligram (dry weight) basis. Blue light inhibited alternariol and alternariol monomethyl ether production 69 and 77%, respectively. Red light gave no reduction of toxin levels. Total lipids were increased 25% when mycelium was grown in blue light as compared with red light or darkness. In white or blue light, but not in red light or darkness, a red-brown pigment accumulated by the mycelium.
Occurrence and Characterization of a Phosphoenolpyruvate: Glucose Phosphotransferase System in a Marine Bacterium,
Serratia marinorubra
Authors: Hodson Robert E. , Azam Farooq
Published: January 2020

The mechanism of
d
-glucose transport in the marine bacterium
Serratia marinorubra
was investigated. Uptake is mediated by a single, constitutive phosphoenolpyruvate:sugar phosphotransferase system (PTS), resulting in phosphorylation of
d
-glucose to
d
-glucose phosphate during transport. The system is saturable (
K

m

= 6.4 × 10
−6
M) and highly temperature dependent, with a
Q
10
of 3.5 between 5 and 15°C. The system is highly specific for
d
-glucose; structurally related sugars and sugar alcohols did not significantly compete with
d
-glucose for transport. The PTS requires Mg
2+
(
K

m

= 2.5 × 10
−4
M), but its activity is otherwise unaffected by salinity changes over the range tested (0 to 35 ‰).
S. marinorubra
differs from other gram-negative organisms (
Escherichia coli
and
Salmonella typhimurium
) in that its glycerol (non-PTS substrate) permease is not regulated by the presence of glucose (PTS substrate).
Differentiation of selected Enterobacteriaceae by pyrolysis-gas-liquid chromatography
Authors: Stern N J , Kotula A W , Pierson M D
Published: January 2020

Pyrolysis-gas-liquid chromatography was used to differentiate selected species of Enterobacteriaceae. Individual cultures of Salmonella typhi, Hafnia alvei, and Proteus vulgaris, and 12 strains of Yersinia enterocolitica were grown in nutrient broth. After harvest and lyophilization, the bacterial samples were pyrolyzed at 900 degrees C, and their volatile fractions were separated on a 50-m capillary column coated with Carbowax 20M. The resulting pyrolysis elution patterns (pyrograms) of the four species were monitored on an integrating console, which was coupled with the chromatographic detector. The pyrograms were divided into 312 30-s time interval areas, and each interval area was normalized in relation to the area of the entire curve. The normalized areas were evaluated by stepwise linear discriminant analysis, and the discriminating component coordinates were used to generate a plot of the canonical variables. Distinct clustering patterns allowed discrimination among the four genera of Enterobacteriaceae studied. The tight clustering of the 12 Y. enterocolitica strains suggests the advantage of pyrolysis-gas-liquid chromatography over traditional approaches for species identification.