Miracle-dz/UniFAR-FTUs huggingface dataset:
Penicillic Acid Production by Blue-Eye Fungi on Various Agricultural Commodities

Of 10 Penicillium species reported to cause blue-eye disease of corn, four (P. martensii, P. palitans, P. cyclopium, P. puberulum) were found capable of producing the mycotoxin penicillic acid on various agricultural commodities. Commodities with high protein contents did not support toxin synthesis. The extent of toxin production varied with the strain of mold, the commodity, and the temperature; low temperatures (1 to 10 C) favored toxin accumulation.
Effect of Several Clay Minerals and Humic Acid on the Survival of Klebsiella aerogenes Exposed to Ultraviolet Irradiation

The effect of various clay minerals and humic acid on the survival of Klebsiella aerogenes exposed to ultraviolet (UV) irradiation was investigated. A protective effect was observed and found to depend on the specific light absorption and light scattering properties of the clay minerals and the humic acid used. The higher the specific absorption, the better was the survival of K. aerogenes after UV irradiation. Bacterial survival was lower in clays saturated with divalent cations (Ca, Zn) than in those homoionic to monovalent cations (K).
Bacterial Ribosome

Chemical Characterization of Ribosomal Proteins. 235 Separation and characterization of ribosomal proteins. 235 Stoichiometry of ribosomal proteins . 236 Primary Structure of Ribosomal RNA. 238 Size and possible subunits. 238 Heterogeneity of rRNA. 239 Base sequence analysis of rRNA. 240 Secondary Structure of rRNA in Isolated States and in Ribosomes. 240
Effect of Serum on the Yield of Lymphocytic Choriomeningitis Virus in Baby Hamster Kidney Cells

The yields of the Armstrong and WE strains of lymphocytic choriomeningitis virus in baby hamster kidney (BHK) cells cultivated in either bovine, calf, fetal bovine, or horse serum were investigated. Lines of BHK cells were established in these sera. When the infected cell lines were observed by immunofluorescence, the per cent fluorescing cells for a given virus strain did not vary. However, for both strains, the extracellular virus yields per cell were significantly greater in the fetal bovine-cell line than in the other serum-cell lines.
Zonal Centrifuge Applied to the Purification of Herpesvirus in the Lucké Frog Kidney Tumor

A series of “winter” and “summer” Lucké kidney tumors of the frog (Rana pipiens) were homogenized and fractionated by differential centrifugation into nuclear, mitochondrial, and mitochondrial supernatant fractions. Winter tumors often contained high concentrations of herpesvirus, whereas no virus was observed in any of the summer tumors. The crude tumor fractions were further purified by rate-zonal sucrose gradient centrifugation in a B-XV zonal rotor. Gradient fractions rich in an enveloped, nucleated form of the herpesvirus from certain winter tumors have induced renal tumors when injected into developing frog embryos. Zonal centrifugation was followed by isopycnic banding of the virus zones for further purification of the different morphological forms of the virus.
GROWTH REQUIREMENTS OF BACTERIAL VIRUSES

The problem of the growth requirements of bacteria is generally considered to consist of a description of those organic and inorganic components in the medium which must penetrate the organism to become available for various metabolic or structural roles essential to the production of a like organism2. It also includes a definition of these roles, metabolic, structural, or both. Implicit in an approach to the problem is the knowledge that the bacteria contain the enzymes capable of synthesizing and assembling their own macromolecular components. Since the growth of bacterial viruses has to date been shown to occur only in an ordered enzymatic environment, as in living cells3, the problem under discussion must be expanded to include the question, "How much of the enzymatic functions of virus synthesis are accomplished by the host cell? " or, conversely, "To what extent does the virus contribute to its own synthesis? " Therefore, it is clear that the problem of the growth requirements of viruses is a far more complex problem than for bacteria. The environment essential for multiplication of any virus consists of the numerous organized macromolecular components of a living cell. These components, in turn, may be affected by variations in the external environment of the cell. Since it is difficult to vary the interior of the cell directly and controllably, the external environment of the infected host has been varied most frequently
Microbial water stress

INTRODUCTION. 803 PHYSICOCHEMICAL PARAMETERS . 804 SOME ECOLOGICAL ASPECTS OF MICROBIAL WATER RELATIONS . 807 Microbial Water Relations and Food . 807 The Saline Environment . 807 The Nonionic Environment . 809 HYPOTHETICAL EXPLANATIONS OF THE TOLERANCE OF LOW WATER ACTIVITY . 809 HALOPHILIC BACTERIA. 811 Cell Envelope and Lipid Biochemistry . 811 Nutrition. 813 Miscellaneous Characteristics . 813 Gas vacuoles . 813 "Satellite" DNA . 813 Halophil bacteriophages . 813 Light Reactions of the Red Halophils . 814 Halophilic Characteristics . 815 Intracellular Physiology . 818 XEROTOLERANT YEASTS . 821 General Biology . 821 Physiology. 822 HALOPHILIC ALGAE . 825 Intracellular Composition . 826 Physiological Role of Glycerol. 827 Regulation of Glycerol Production . 828 Physiological Basis of Algal Halophilism. 828 Algae Other than D nalie . 829 COMPATIBLE SOLUTES . 829 Electrolytes. 829 Nonelectrolytes. 833 Physicochemical Mechanism of Nonelectrolyte Action . 835 Regulation of Compatible Solute Accumulation . 837 LOOSE ENDS 838 Survival. 840 SUMMARY . 841 LITERATURE CITED. 841
Microbial growth rates in nature

INTRODUCTION . Commitment to Nature. What is Nature? POPULATION PROBLEMS . ASSESSMENT OF MICROBIAL NUMBERS OR MASS. DEFINING BOUNDARIES OF THE HABITAT . ARTIFICIAL SUBSTRATES . USE OF THE MICROSCOPE IN NATURE . MEASUREMENT OF GROWTH RATE OF SINGLE ORGANISMS. GROWTH RATES OF DEVELOPING MICROCOLONIES. GROWTH RATES OF FILAMENTOUS ORGANISMS . METHODS BASED ON ANALYSIS OF THE CELL-DIVISION CYCLE. Labeled Thymidine Methods. GROWTH RATES OF PROCARYOTES AS MEASURED BY THYMIDINE AUTORADIOGRAPHY Ecological Approximations for Labeling Experiments. Rate of Appearance of Unlabeled Cells. GENETIC METHODS . METHODS ESPECIALLY SUITED TO STEADY-STATE POPULATIONS. INOCULUM SIZE: RATE OF EFFECT. CONCLUDING STATEMENT . LITERATURE CITED.
Occurrence of Vibrio parahaemolyticus and Related Hemolytic Vibrios in Marine Environments of Washington State

Samples of sediment, water, and fauna were tested for the presence of Vibrio parahaemolyticus and the related biotype V. alginolyticus. Altogether, 379 samples were analyzed quantitatively by using a starch-agar medium. Invertebrate and sediment samples were invariably positive for V. parahaemolyticus, whereas water samples were quite variable. Samples of the Pacific oyster (Crassostrea gigas), obtained on a regular basis for 26 months from a single environment, showed a close correlation between total numbers of mesophilic vibrios and the overlying water temperature; the seasonal counts of oysters ranged from less than 10 to greater than 100,000 per g. Ecological implications and possible pathogenicity of these vibrios are discussed.
RUMEN ORGANISMS II

In two previous publications (Gall and Huhtanen, 1951; Huhtanen and Gall, 1953) fourteen rumen organisms have been described. One group of five type cultures includes four rods and one coccus that are fast-growing, easy to culture organisms which produce lactic acid and are associated with the rumen of animals, especially calves, that are heavy grain consumers. The other group of rumen organisms consists of nine fastidious rods that attack fiber producing shortchain fatty acids and are associated -especially with the rumen of adult animals consuming mostly roughage. Eight other types of organisms, five rods and three cocci, have been isolated repeatedly in large numbers from the rumen, and because they meet the criteria for true rumen organisms, they have been studied and designated as type cultures of rumen bacteria. These eight organisms will be described.
II. POSSIBLE MECHANISMS WHEREBY ENDOTOXINS EVOKE INCREASED NONSPECIFIC RESISTANCE TO INFECTION

Experiments in which the administration of substances to the host was followed by a rapid change in host resistance to infection have been described many times. The early literature has been well assembled and reviewed by Philipson (19). However, no unifying concepts of either common mechanisms of action or common substances present in administered materials were formulated, so that the phenomena largely remained as isolated and individual examples which had been elicited in special circumstances. On examination of the reported findings, among them those of Pfeiffer and Issaeff (18), Teague and McWilliams, (26) and Philipson (19), it is clear that a number of such phenomena may well have been initiated by endotoxin. Contemporary work in this field had its beginnings in observations of a similar nature. In the first descriptions, administration of bacterial cellwall preparations (20) or whole bacteria (8) was found to result in a temporary and rapid increase in the resistance of mice to infection with antigenically unrelated gram-negative bacteria. Shortly thereafter the active component in these preparations was identified as endotoxin (12, 21). At that time it was thought that the alterations in resistance might be explained as a consequence of the interaction of substrate (endotoxin) with a serum component concerned with the bactericidal reaction, which resulted in an initial depletion followed by a temporary overproduction of the latter substance. The actual pattern of altered resistance fitted this view very well in that, for about 3 hr after receiving large doses of endo-
Bacterial Metabolism of Arylsulfonates

Pseudomonas testosteroni H-8 utilizes as sole carbon source benzene sulfonate (BS), p-toluene sulfonate (pTS), and ethylbenzene sulfonate (EBS) but not higher homologs. Growth on BS was rapid (generation time, 3 hr) and efficient (Y = 57), and resulted in accumulation of sulfate. As the culture is acid-sensitive, the medium must be heavily buffered to permit extensive growth. The BS oxidase system is inducible. Cells grown on BS, but not glutamate, oxidized BS, pTS, or EBS without lag (QO2 = 50 to 100). Oxygen uptake on BS is temperature-dependent and sensitive to cyanide. Complete oxidation of 1 μmole of BS consumed approximately 5.7 μmoles of oxygen.
Microbial Flora of Pond-Reared Brown Shrimp (Penaeus aztecus)

Agar plate counts and microbial types are reported for brown shrimp reared in 2-acre natural marshland and in 0.5-acre artificial ponds during June to October 1970. Bacterial counts of pond-reared shrimp ranged from 5 × 104 to 5.5 × 106 per g. At final harvest in October, bacterial counts ranged from 2 × 105 to 5.5 × 106 per g. In marsh ponds, bacterial counts of shrimp and pond water were lowest in August when both water temperature and salinity were high. Coryneform bacteria and to a lesser extent Vibrio were the predominant isolates from fresh pond shrimp. Shrimp stored at 3 to 5 C for 7 days were acceptable as judged by appearance and odor. Between 7 and 14 days of refrigerated storage, bacterial counts increased sharply and about 50% of the samples became unacceptable. Refrigerated storage of pond shrimp caused increases in coryneform bacteria and micrococci and decreases in Vibrio, Flavobacterium, Moraxella, and Bacillus species. Pseudomonas species were not significant in fresh or stored pond shrimp. The microbial flora of pond water usually was dominated by coryneform bacteria, Flavobacterium, Moraxella, and Bacillus species.
Effects on Growth and Toxin Production of Exposure of Spores of Clostridium botulinum Type F to Sublethal Doses of Gamma Irradiation

Spores of the Langeland strain of Clostridium botulinum type F were grown at 30 or 10 C after exposure to 0.0, 0.1, or 0.2 megarad of cesium-137 gamma irradiation. When incubated at 30 C, cultures irradiated at the 0.2-megarad level reached the stationary growth phase 15 hr earlier than the 0.0 or 0.1 megarad-irradiated cultures. This was not the result of earlier or more frequent germination of the irradiated spores, the formation of larger individual cells, filament formation, or cell clumping. It appeared to result from elimination of a lytic phenomenon noted in 0.0 and 0.1 megarad-irradiated cultures after 26 and 29 hr of incubation, respectively, which was followed by a second exponential-growth response 5 hr later in these cultures. The time of toxin appearance in culture supernatant fractions was independent of prior irradiation treatment and occurred after 36 hr of incubation. Toxin release was essentially logarithmic until maximal titers were reached and maximal toxin titers were higher in irradiated than in unirradiated cultures. The higher toxin level was sustained over a period of 23 days of 30 C. Toxin produced in the 30 C cultures could not be trypsin-activated. An incubation temperature of 10 C resulted in no outgrowth of spores subjected to 0.2 megarad of irradiation, although spore germination did occur. At 10 C, outgrowth of the 0.1-megarad culture was faster with slightly higher quantities of a more stable toxin than was seen in the unirradiated control. At 10 C, trypsinization was necessary to demonstrate the toxin present in the cultures.
Volatile Fatty Acids and the Inhibition of Escherichia coli Growth by Rumen Fluid

Concentrations of volatile fatty acids (VFA) normally found in bovine rumen fluid inhibited growth of Escherichia coli in Antibiotic Medium 3. Acetic, propionic, and butyric acids each produced growth inhibition which was markedly pH-dependent. Little inhibition was observed at pH 7.0, and inhibition increased with decreasing pH. A combination of 60 μmoles of acetate, 20 μmoles of propionate, and 15 μmoles of butyrate per ml gave 96, 69, and 2% inhibition at pH 6.0, 6.5, and 7.0, respectively. Rumen fluid (50%) gave 89 and 48% inhibition at pH 6.0 and 6.5, respectively, and growth stimulation (22%) at pH 7.0. Rumen fluid inhibitory activity was heat-stable, was not precipitated by 63% ethyl alcohol, and was lost by dialysis and by treatment with anion-exchange resins but not with cation-exchange resins. These results are consistent with the idea that VFA are the inhibitory substances in rumen fluid. Previous results which indicated that rumen fluid VFA did not inhibit E. coli growth were due to lack of careful control of the final pH of the growth medium. The E. coli strain used does not grow in rumen fluid alone at pH 7.0.
Roles of amino acid activating enzymes in cellular physiology

INTRODUCTION . Cellular Responses to Amino Acid Restriction. Key Position ofAminoacyl sRNA Synthetases. MUTANTS WITH MODIFiED AMiNOACYL sRNA SYNTHETASES. Conditionally Expressed Mutations. General background . Temperature-conditional mutations. Streptomycin-conditional mutations. Methods for isolating conditional mutants. Mutations Conferring Analogue Resistance. Naturally Occurring Variants. Epi-regulatory Mutations. GENETIC AND METABOLIC CHARACTERIZATION OF MUTANTS WITH MODIFIED SYNTHETASES. Valyl sRNA Synthetase . Glycyl sRNA Synthetase . Histidyl sRNA Synthetase. Alanyl sRNA Synthetase . Arginyl sRNA Synthetase . Phenylalanyl sRNA Synthetase . PHYSIOLOGICAL RESPONSES OF MUTANTS WITH MODIFED SYNTHETASES. Regulation ofRNA Synthesis . Regulation ofDNA Synthesis. Repression ofBiosynthetic Enzzymes. End-Product Inhibition ofBiosynthetic Pathways. Catabolite Repression . PHAGE-INDUCED MODIFICATION OF VALYL sRNA SYNTHETASE ACrIVITY. SUMMARY AND FUTURE GoALS. LITERATURE CITED . 701 701 703 704 704 704 704 704 705 705 705 705
Growth Rate of Sphaerotilus in a Thermally Polluted Environment

In situ growth of Sphaerotilus on microscope slides immersed in a thermally polluted stream was studied. Ultraviolet radiation was used to differentiate between passive attachment of organisms from the water and growth of the organisms on the slides. Colonization of the slides in this environment took place solely by means of swarmer cells. A generation time of 2.3 hr was obtained at a water temperature of 18-22 C.
Evaluation of Live Tularemia Vaccine Prepared in a Chemically Defined Medium

A chemically defined medium was prepared which adequately supported growth of a vaccine strain of Pasteurella tularensis. This medium differed from those previously described in: (i) concentration of components, (ii) a requirement for calcium pantothenate to obtain increased growth, and (iii) a low initial pH. Varying the concentration of individual components up to 10 times the standard amount did not increase the viable population or affect dissociation. The vaccine strain grown in this chemically defined medium, although lower in viable population, appears to retain its identity and to be equal in potency to that prepared by the conventional method. This preliminary study indicates the potential utility of this medium as a basis for controlled studies of a live bacterial vaccine in terms of growth characteristics, dissociation, virulence, and immunogenicity.
Incorporation of [3H]Leucine and [3H]Valine into Protein of Freshwater Bacteria: Field Applications

Incorporation of leucine and valine into proteins of freshwater bacteria as a measure of bacterial production was tested in two eutrophic Danish lakes and was related to bacterial production measured by thymidine incorporation. In a depth profile (0 to 8 m) in Frederiksborg Castle Lake, incorporation of 100 nM leucine and valine gave similar rates of protein production. In terms of carbon, this production was about 50% lower than incorporation of 10 nM thymidine. In another depth profile in the same lake, incorporations of 10 nM valine and 100 nM leucine were identical, but differed from incorporations of 10 nM leucine and 100 nM valine. Bacterial carbon production calculated from incorporations of 10 nM thymidine and 10 nM leucine was similar, whereas 10 nM valine and 100 nM leucine and valine indicated an up to 2.4-fold-higher rate of carbon production. In a diel study in Lake Bagsvaerd, incorporation of 100 nM leucine and valine indicated a similar protein production, but the calculated carbon production was about 1.9-fold higher than the production based on uptake of 10 nM thymidine. Different diel changes in incorporation of the two amino acids and in incorporation of thymidine were observed. In both lakes, concentrations of naturally occurring leucine and valine were <5 nM in most samples. This means that the specific activity of a 3H isotope added at a concentration of 100 nM usually was diluted a maximum of 5%. Net assimilation of natural free amino acids in the lakes sustained 8 to 69% of the net bacterial carbon requirement, estimated from incorporation of leucine, valine, or thymidine. The present results indicate that incorporation of leucine and valine permits realistic measurements of bacterial production in freshwater environments.
Potential Pathogens in the Environment: Cultural Reactions and Nucleic Acid Studies on Klebsiella pneumoniae from Clinical and Environmental Sources

The phenotypic and nucleic acid properties of Klebsiella pneumoniae have been studied on cultures obtained from six different habitats (humans, vegetables, seeds, trees, rivers, and pulp mills). The 19 cultural reactions of 107 isolates varied significantly only in tryptophanase activity and dulcitol fermentation. The percentage of guanine plus cytosine base composition of 41 isolates varied from 53.9 to 59.2%. The range of percentage of guanine plus cytosine base composition for environmental klebsiellas was broader than that for the cultures of human origin. The range of deoxyribonucleic acid relative reassociation (homology) to the human K. pneumoniae reference strain extended from 5% to 100% and the chromosome molecular weights ranged from 2,200 × 106 to 3,000 × 106. The species of K. pneumoniae is thus molecularly more heterogeneous than previously thought and most isolates of human, pulp mill, and river origin are genetically indistinguishable. The presence of K. pneumoniae therefore represents a deterioration of the microbiological quality of the environment and should be considered of public health significance. At the present time the health significance of the molecularly more divergent strains, primarily of vegetable and seed origin, their relationship to klebsiellas of human origin, or to other genera of the Enterobacteriaceae is unclear.
Microbial Penetration of Muslin- and Paper-Wrapped Sterile Packs Stored on Open Shelves and in Closed Cabinets

Microbial penetration of sterile packs was studied using single-wrap (two layers) muslin, double-wrap (four layers) muslin, and two-way crepe paper (single layer) to wrap 20 gauze sponges (2 by 2 inch). These packs were stored in the central sterile supply departments of two hospitals and processed for sterility at predetermined intervals. Microorganisms penetrated single-wrap muslin as early as 3 days and double-wrap muslin and single-wrap two-way crepe paper in 21 to 28 days stored in open shelves. The time required for microbial penetration was at least twice as long when closed cabinets were used. Single-wrap muslin packs stored in sealed, impervious plastic bags remained sterile for at least 9 months. All sterile materials in pervious wrappers should be handled as little as possible and then only with extreme care and caution. Closed cabinets offer more protection than open shelves, and single wrappers are not recommended.
Blood transfusion alters the course and outcome of Plasmodium chabaudi AS infection in mice

The importance of severe anemia in the mortality of susceptible A/J mice during blood-stage Plasmodium chabaudi AS infection was assessed. Blood transfusion during and 2 to 3 days after peak parasitemia rescued 90% of susceptible mice from severe anemia and death and allowed these mice to clear the infection and acquire immunity to reinfection. However, blood transfusion prolonged the patency of the infection for up to 5 days after peak parasitemia. Blood transfusions in resistant C57BL/6 mice produced an identical effect, that is, prolongation of the patency of parasitemia. In addition, blood transfusion increased the numbers of gametocytes in both mouse strains. In both strains of mice, the rapid reduction in parasitemia, which occurs during crisis, was associated with the development of moderate levels of anemia. The possible mechanisms for the modulation of parasitemia by blood transfusion and the implications of the present observations for our understanding of the events which occur during crisis are discussed. It is proposed that parasitologic crisis is induced and/or maintained by physiological alterations associated with anemia.
EPISOME-MEDIATED TRANSFER OF DRUG RESISTANCE IN ENTEROBACTERIACEAE VIII

Watanabe, Tsutomu (Keio University School of Medicine, Tokyo, Japan), Chizuko Ogata, and Sachiko Sato. Episome-mediated transfer of drug resistance in Enterobacteriaceae. VIII. Six-drug-resistance R factor. J. Bacteriol. 88:922–928. 1964. —The multiple-drug-resistant Escherichia coli strain isolated by Lebek in 1963 was found to transfer resistance to sulfonamide, streptomycin, chloramphenicol, tetracycline, kanamycin, and neomycin together by conjugation, as well as by transduction with phage P1kc, suggesting that these drug-resistance markers are carried by a single R factor (R6). The results of transductional and spontaneous segregations of the drug-resistance markers of R6 have shown that R6 has independent genetic determinants for sulfonamide, streptomycin, chloramphenicol, tetracycline, and kanamycin-neomycin resistance. Resistance to kanamycin and neomycin is probably controlled by a single gene, because no segregation was observed between these two. The resistance transfer factor of R6 was found to be of the fi+ type.