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Bacterial Activities And Crop Production, Percy Edgar Brown 2017 Iowa State College

Bacterial Activities And Crop Production, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Until the present time studies in soil bacteriology have dealt almost exclusively with the occurrence and activities of microorganisms in the soil and no attempt has been made to interpret experimental results from the standpoint of crop production. This is due, of course, to the fact that as a science soil bacteriology is scarcely out of its infancy and the preliminary investigations in any science must of necessity deal mainly with underlying principles and such studies are always apt to be rather fragmentary in character.


Slimy And Ropy Milk, R. E. Buchanan, B. W. Hammer 2017 Iowa State College

Slimy And Ropy Milk, R. E. Buchanan, B. W. Hammer

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

A study of slimy and ropy milk sent for examination to the dairy bacteriological laboratories of Iowa State College has shown the following:

1. Cultures of organisms secured from slimy starters, apparently typical Streptococcus lacticus forms, sometimes showed marked capacity to produce ropiness when inoculated into sterile milk. This slime producing power is evidently a variable characteristic, appearing and disappearing without apparent cause.

2. Associative action of organisms in some cases is responsible for ropiness. Two organisms, neither of which alone can cause ropiness, may, when grown together, cause the medium to become slimy.

3. Bacterium (lactis) viscosum is one ...


Bacteriological Studies On Two Yellow Milk Organisms, B. W. Hammer 2017 Iowa State College

Bacteriological Studies On Two Yellow Milk Organisms, B. W. Hammer

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The different milk constituents vary greatly in their susceptibility to the action of the bacteria that make up the flora commonly found in milk. At ordinary temperatures in raw milk, the lactose is soon attacked and acid formed, but if the acid producing organisms are destroyed by some such procedure as heating, pronounced changes soon take place in the casein. The fat is one of the milk constituents that is more resistant to bacterial action, yet even in it striking changes are observed under certain conditions. Some of the common milk organisms, even some of the acid producing types, are ...


Bacteriological Studies On The Coagulation Of Evaporated Milk, B. W. Hammer 2017 Iowa State College

Bacteriological Studies On The Coagulation Of Evaporated Milk, B. W. Hammer

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The value of milk as a food has led to many attempts at its preservation until at the present time various kinds of dried and canned milks are manufactured. The canned milks, because of the water contained in them, are open to bacteriological changes unless the action of microorganisms is overcome by either killing those present or by making the conditions unsuited to their growth.


A Bacteriological Study Of Blue Milk, B. W. Hammer 2017 Iowa State College

A Bacteriological Study Of Blue Milk, B. W. Hammer

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

In October, 1913, the receipt of a sample of blue milk by the dairy section of the Iowa Agricultural Experiment Station prompted an investigation of this uncommon phenomenon. Careful study of the organism involved proved it to be Bac. cyanogenes, the same organism that has been isolated in other instances of blue milk. As far as is known, this organism is entirely harmless and milk which is turned blue by it is objectionable only on account of its color.


Sulfofication In Soils, P. E. Brown, E. H. Kellogg 2017 Iowa State College

Sulfofication In Soils, P. E. Brown, E. H. Kellogg

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Sulfur has long been known to be one of the essential plant food constituents. It has always been believed, however, that there was sufficient present in all soils for the optimum growth of crops. This assumption has been very largely based on Wolff's analyses of the ashes of various crops which showed the presence of very small amounts of sulfur.

The recent work of many investigators has demonstrated, however, that the amount of sulfur in plant materials as determined in the ash is, in most cases, entirely too low; that there is a considerable loss of sulfur in the ...


Bacteriological Studies Of Field Soils, Iii. The Effects Of Barnyard Manure, Percy Edgar Brown 2017 Iowa State College

Bacteriological Studies Of Field Soils, Iii. The Effects Of Barnyard Manure, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The conclusions which may be drawn from the experiments upon the effects of barnyard manure on bacteriological activities of field S'oils presented in this bulletin are as follows:

1. Applications of manure up to sixteen tons per acre increased the numbers of organisms in the soil as shown by the growth on modified synthetic and albumen agar. The ammonifying power of the soil as shown by tests with the casein-fresh soil, albumen-fresh soil, dried blood-fresh soil, and dried blood-air-dried soil methods, and the nitrifying power tested by the ammonium sulfate-fresh soil, and the ammonium sulfate-air- dried soil methods were ...


Methods For The Bacteriological Examination Of Soils, Percy Edgar Brown 2017 Iowa State College

Methods For The Bacteriological Examination Of Soils, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Because the idea of examining soils bacteriologically owed its inception to the development of the gelatine plate method for isolating pure cultures, very naturally the first investigations of soil bacteria were by the use of plate cultures. the studies, therefore, were purely quantitative in nature. The results secured by the pioneers in this work demonstrated some facts of considerable interest, but it soon became evident that mere quantitative determinations of the bacteria in soils were inadequate to give information regarding the relation of such organisms and their activities to the fertility of the soil.


Bacteria At Different Depths In Some Typical Iowa Soils, Percy Edgar Brown 2017 Iowa State College

Bacteria At Different Depths In Some Typical Iowa Soils, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. In the different soil types, as well as in the same soil under different rotations, the greatest number of organisms occurred at a depth of 4 inches.

2. Bacteria were found in considerable numbers at much lower depths in the loess soil than in the drift soil.

3. There was a more or less gradual decrease in numbers to a depth of 3, 5 and in one case of fifteen feet. No sudden increases were observed even where gains in moisture occurred.

4. The greatest decrease in numbers of organisms occurred within the first 12 inches and in some ...


Bacteriological Studies Of Field Soils, Ii. The Effects Of Continuous Cropping And Various Rotations, Percy Edgar Brown 2017 Iowa State College

Bacteriological Studies Of Field Soils, Ii. The Effects Of Continuous Cropping And Various Rotations, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

From a bacteriological study of soil plots under both continuous cropping and various crop rotations, these general conclusions were drawn:

1. The rotation of crops caused the development of greater numbers of organisms in the soil and of greater ammonifying, nitrifying, and nitrogen-fixing power by the soil, than continuous cropping either to corn or to clover.

2. Greater numbers of organisms, greater ammonifying, nitrifying, and nitrogen-fixing powers were found in a soil under a three year rotation of corn, oats, and clover, than in a soil under a two year rotation of corn and oats, or in a soil under ...


Bacteriological Studies Of Field Soils, I. The Effects Of Lime, Percy Edgar Brown 2017 Iowa State College

Bacteriological Studies Of Field Soils, I. The Effects Of Lime, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. Applications of limestone up to three tons per acre increased the total number of soil bacteria which develop on "modified synthetic" agar plates.

2. These increases probably occurred in species more resistant to drought.

3. The three ton application gave a proportionately greater increase in numbers than the two tons.

4. Application of limestone up to three tons per acre increased the ammonlfying, the nitrifying, anil the nitrogen fixing powers of the soil.

5. The ammonification of dried blood and cottonseed meal did not run parallel in tests of field soils subjected to continued drought.

6. The three ton ...


Bacterial Activities In Frozen Soils, Percy Edgar Brown, Roy Eugene Smith 2017 Iowa State College

Bacterial Activities In Frozen Soils, Percy Edgar Brown, Roy Eugene Smith

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. By means of the" modified synthetic" agar plate method bacteria are shown to be present in large numbers in a typical Wisconsin drift soil when it is completely frozen and the temperature is below zero degrees Centigrade; furthermore, increases and decreases in numbers of organisms occur during this period and large numbers are found after the soil has been frozen for a considerable period than before it begins to freeze.

2. During the fall season, the number of bacteria present in the soil diminishes gradually with the lowering of the temperature.

3. Frozen soils possess a much greater ammonifying ...


Molecular Biology Of A Surface-Exposed Protein Family Of Bartonella Bacilliformis, Hannah Fay 2017 University of Montana

Molecular Biology Of A Surface-Exposed Protein Family Of Bartonella Bacilliformis, Hannah Fay

Undergraduate Theses and Professional Papers

Bartonella bacilliformis is a gram negative alpha-proteobacterium native to the Andes of South America. Bartonella causes Carrion’s disease, a potentially life threatening disease transmitted by the sand fly. It has a mortality rate of 88% when untreated and 10% when treated. Diagnostics and control measures for the disease are underdeveloped and no vaccine is available. Recent outbreaks indicate that the range of the pathogen is increasing with nearly 1.7 million people in western South America at risk. Little is known about the epidemiology and pathogenesis of B. bacilliformis. Recent research done by UC San Diego found a paralogous ...


Xpert Mtb/Rif Assay Shows Faster Clearance Of Mycobacterium Tuberculosis Dna With Higher Levels Of Rifapentine Exposure., A Jayakumar, R M Savic, C K Everett, Debra Benator, D Alland, C M Heilig, M Weiner, S O Friedrich, N A Martinson, A Kerrigan, C Zamudio, S V Goldberg, W C Whitworth, J L Davis, P Nahid 2016 George Washington University

Xpert Mtb/Rif Assay Shows Faster Clearance Of Mycobacterium Tuberculosis Dna With Higher Levels Of Rifapentine Exposure., A Jayakumar, R M Savic, C K Everett, Debra Benator, D Alland, C M Heilig, M Weiner, S O Friedrich, N A Martinson, A Kerrigan, C Zamudio, S V Goldberg, W C Whitworth, J L Davis, P Nahid

Medicine Faculty Publications

The Xpert MTB/RIF assay is both sensitive and specific as a diagnostic test. Xpert also reports quantitative output in cycle threshold (CT) values, which may provide a dynamic measure of sputum bacillary burden when used longitudinally. We evaluated the relationship between Xpert CT trajectory and drug exposure during tuberculosis (TB) treatment to assess the potential utility of Xpert CT for treatment monitoring. We obtained serial sputum samples from patients with smear-positive pulmonary TB who were consecutively enrolled at 10 international clinical trial sites participating in study 29X, a CDC-sponsored Tuberculosis Trials Consortium study evaluating the tolerability, safety, and antimicrobial ...


Genomes Of Gardnerella Strains Reveal An Abundance Of Prophages Within The Bladder Microbiome, Kema Malki, Jason W. Shapiro, Travis Kyle Price, Evann Elizabeth Hilt, Krystal Thomas-White, Trina Sircar, Amy B. Rosenfeld, Michael J. Zilliox, Alan J. Wolfe, Catherine Putonti 2016 Loyola University Chicago

Genomes Of Gardnerella Strains Reveal An Abundance Of Prophages Within The Bladder Microbiome, Kema Malki, Jason W. Shapiro, Travis Kyle Price, Evann Elizabeth Hilt, Krystal Thomas-White, Trina Sircar, Amy B. Rosenfeld, Michael J. Zilliox, Alan J. Wolfe, Catherine Putonti

Bioinformatics Faculty Publications

Bacterial surveys of the vaginal and bladder human microbiota have revealed an abundance of many similar bacterial taxa. As the bladder was once thought to be sterile, the complex interactions between microbes within the bladder have yet to be characterized. To initiate this process, we have begun sequencing isolates, including the clinically relevant genus Gardnerella. Herein, we present the genomic sequences of four Gardnerella strains isolated from the bladders of women with symptoms of urgency urinary incontinence; these are the first Gardnerella genomes produced from this niche. Congruent to genomic characterization of Gardnerella isolates from the reproductive tract, isolates from ...


Draft Genome Sequence For A Urinary Isolate Of Nosocomiicoccus Ampullae, Evann Elizabeth Hilt, Travis Kyle Price, Katherine Diebel, Catherine Putonti, Alan J. Wolfe 2016 Loyola University Chicago

Draft Genome Sequence For A Urinary Isolate Of Nosocomiicoccus Ampullae, Evann Elizabeth Hilt, Travis Kyle Price, Katherine Diebel, Catherine Putonti, Alan J. Wolfe

Bioinformatics Faculty Publications

A draft genome sequence for a urinary isolate of Nosocomiicoccus ampullae (UMB0853) was investigated. The size of the genome was 1,578,043 bp, with an observed G+C content of 36.1%. Annotation revealed 10 rRNA sequences, 40 tRNA genes, and 1,532 protein-coding sequences. Genome coverage was 727× and consisted of 32 contigs, with an N50 of 109,831 bp.


Characterization Of Antimicrobial Activity Of Culturable Bacteria Isolated From Krubera-Voronja Cave, Aiste Klusaite, Vida Vickackaite, Birute Vaitkeviciene, Rasa Karnickaite, Dominykas Bukelskis, Ieva Kieraite-Aleksandrova, Nomeda Kuisiene 2016 Vilnius University

Characterization Of Antimicrobial Activity Of Culturable Bacteria Isolated From Krubera-Voronja Cave, Aiste Klusaite, Vida Vickackaite, Birute Vaitkeviciene, Rasa Karnickaite, Dominykas Bukelskis, Ieva Kieraite-Aleksandrova, Nomeda Kuisiene

International Journal of Speleology

In the present study we aimed to perform the first analysis of antimicrobial activity of bacteria isolated from Krubera-Voronja Cave, with the main focus on their activity against Grampositive bacteria, including Gram-positive pathogens. Using five different media, in total 874 heterotrophic cultures were isolated from water and sediment samples collected in Krubera-Voronja Cave at a depth from 220 m to 1640 m. 14.0% of all isolates demonstrated antibacterial activity against Gram-positive and Gram-negative test microorganisms. Our results show that this percentage was not uniform; it increased with the sampling depth and was the highest in the lower part of ...


Genome Sequences And Annotation Of Two Urinary Isolates Of E. Coli, Travis Kyle Price, Arya Mehtash, Laurynas Kalesinskas, Kema Malki, Evann Elizabeth Hilt, Catherine Putonti, Alan J. Wolfe 2016 Loyola University Chicago

Genome Sequences And Annotation Of Two Urinary Isolates Of E. Coli, Travis Kyle Price, Arya Mehtash, Laurynas Kalesinskas, Kema Malki, Evann Elizabeth Hilt, Catherine Putonti, Alan J. Wolfe

Bioinformatics Faculty Publications

The genus Escherichia includes pathogens and commensals. Bladder infections (cystitis) result most often from colonization of the bladder by uropathogenic E. coli strains. In contrast, a poorly defined condition called asymptomatic bacteriuria results from colonization of the bladder with E. coli strains without symptoms. As part of an on-going attempt to identify and characterize the newly discovered female urinary microbiota, we report the genome sequences and annotation of two urinary isolates of E. coli: one (E78) was isolated from a female patient who self-reported cystitis; the other (E75) was isolated from a female patient who reported that she did not ...


Presence Of A Prophage Determines Temperature-Dependent Capsule Production In Streptococcus Pyogenes., Leslie Brown, Jeong-Ho Kim, Kyu Hong Cho 2016 George Washington University

Presence Of A Prophage Determines Temperature-Dependent Capsule Production In Streptococcus Pyogenes., Leslie Brown, Jeong-Ho Kim, Kyu Hong Cho

Biochemistry and Molecular Medicine Faculty Publications

A hyaluronic acid capsule is a major virulence factor in the pathogenesis of Streptococcus pyogenes. It acts as an anti-phagocytic agent and adhesin to keratinocytes. The expression of the capsule is primarily regulated at the transcriptional level by the two-component regulatory system CovRS, in which CovR acts as a transcriptional repressor. The covRS genes are frequently mutated in many invasive strains, and a subset of the invasive CovRS mutants does not produce a detectable level of the capsule at 37 °C, but produces a significant amount of the capsule at sub-body temperatures. Here, we report that a prophage has a ...


The Pesticidal Cry6aa Toxin From Bacillus Thuringiensis Is Structurally Similar To Hlye-Family Alpha Pore-Forming Toxins, Alexey Dementiev, Anand Sitaram, Yan Hu, Raffi V. Aroian, Colin Berry 2016 Shamrock Structures LLC

The Pesticidal Cry6aa Toxin From Bacillus Thuringiensis Is Structurally Similar To Hlye-Family Alpha Pore-Forming Toxins, Alexey Dementiev, Anand Sitaram, Yan Hu, Raffi V. Aroian, Colin Berry

Open Access Articles

BACKGROUND: The Cry6 family of proteins from Bacillus thuringiensis represents a group of powerful toxins with great potential for use in the control of coleopteran insects and of nematode parasites of importance to agriculture. These proteins are unrelated to other insecticidal toxins at the level of their primary sequences and the structure and function of these proteins has been poorly studied to date. This has inhibited our understanding of these toxins and their mode of action, along with our ability to manipulate the proteins to alter their activity to our advantage. To increase our understanding of their mode of action ...


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