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Detection Of Presumptive Pathogens In Ground Beef From Supermarket And Farmers' Market Sources, Paige L. Stanley, Taylor A. Winslow, Indiren Pillay 2017 Georgia College & State University

Detection Of Presumptive Pathogens In Ground Beef From Supermarket And Farmers' Market Sources, Paige L. Stanley, Taylor A. Winslow, Indiren Pillay

Georgia Journal of Science

This study investigates whether specific pathogens are more prevalent in retail meat sold by supermarkets compared to locally sourced markets. Ground beef samples were obtained from conventional ‘big box’ supermarkets and from local, farmers’ markets and examined for the presence of two pathogens, Escherichia coli O157,H7 and Salmonella. For the detection of E. coli O157,H7, homogenized meat samples were enriched overnight in modified EC medium with novobiocin. The enriched cultures were selected onto MacConkey agar with sorbitol, cefixime and tellurite. Presumptive positive colonies were subcultured onto tryptic soy agar with yeast extract and further tested for positive indole ...


Effect Of Seasonal Conditions And Soil Treatment On Bacteria And Molds In Soil, P. E. Brown, W. V. Halversen 2017 Iowa State College

Effect Of Seasonal Conditions And Soil Treatment On Bacteria And Molds In Soil, P. E. Brown, W. V. Halversen

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The study of the microorganic population of the soil has revealed many interesting facts but none more significant nor of more far-reaching importance than the discovery that molds occur in soils and perform various functions which directly or indirectly exert considerable influence on soil fertility.

The occurrence and activities of bacteria in the soil has been the subject of extensive inquiry and much knowledge along this line has been accumulated. These organisms have been found to occur in large numbers in practically all soils and to play a prominent part in the reactions which must necessarily take place in soils ...


Soil Inoculation With Azotobacter, Paul Emerson 2017 Iowa State College

Soil Inoculation With Azotobacter, Paul Emerson

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Following the discovery of the nitrogen fixing powers of the symbiotic bacteria in the soil, early investigators found that the power of utilizing the free atmospheric nitrogen was not confined to the symbiotic bacteria alone. They noted increases in soils which had borne no legumes and they found that fallow soils in particular increased appreciably in nitrogen content. These . facts stimulated researches which led to the discovery of many forms of bacteria which are able, when growing alone, to fix nitrogen from the air. The chief of these is now known as the azotobacter group.


Effects Of Certain Alkali Salts On Ammonification, P. E. Brown, D. R. Johnson 2017 Iowa State College

Effects Of Certain Alkali Salts On Ammonification, P. E. Brown, D. R. Johnson

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The occurrence of so-called" alkali spots" in certain Iowa soils has been nnted in recent publications, these spots are found only in the Wisconsin drift soil area, in association with peat deposits, and are the result of course of peculiarly poor drainage conditions. It is unnecessary here to consider further the causes of these formations or the methods which should be followed in reclaiming the areas affected as these points have been discussed in the publications referred to. It will be sufficient to call attention to the results of the chemical studies of the spots and to consider briefly some ...


Do You Really Want A Hunter-Gatherer Microbiota? Perils And Pitfalls For Your Gut, Michael Ruscio 2017 Dr. Michael Ruscio

Do You Really Want A Hunter-Gatherer Microbiota? Perils And Pitfalls For Your Gut, Michael Ruscio

Journal of Evolution and Health

Clinicians have long understood the immense impact the health of our gut has on things like weight, energy, depression, autoimmunity and more. With the recent advancements in microbiota research we have learned much more about this connection. Like never before we understand how we can alleviate chronic health conditions and enhance well-being through improving the health of the gut.

However, with this increased research has also come over speculation and ill-informed recommendations. This has high impact on today's healthcare professional or consumer who could unintentionally do harm. For example by replicating the microbiota of hunter-gatherers of Africa, we could ...


Pulmonary Surfactant Fortified With Cath-2 As A Novel Therapy For Bacterial Pneumonia, Brandon J. Baer 2017 University of Western Ontario

Pulmonary Surfactant Fortified With Cath-2 As A Novel Therapy For Bacterial Pneumonia, Brandon J. Baer

Western Research Forum

Background: Bacterial pneumonia is a leading cause of death worldwide, with high mortality rates persisting even after antibiotic treatment. Current treatments for pneumonia involve administration of antibiotics, however after the bacteria are killed they release toxic substances that induce inflammation and lung dysfunction. Host defense peptides represent a potential solution to this problem through their ability to down regulate inflammation. However, effective delivery to the lung is difficult because of the complex branching structure of the airways. My study addresses this delivery problem by using exogenous surfactant, a pulmonary delivery vehicle capable of improving spreading of these peptides throughout the ...


Flagellar Formation In C-Ring-Defective Mutants By Overproduction Of Flii, The Atpase Specific For Flagellar Type Iii Secretion, Manabu Konishi, Masaomi Kanbe, Jonathan L. McMurry, Shin-Ichi Aizawa 2017 Prefectural University of Hiroshima

Flagellar Formation In C-Ring-Defective Mutants By Overproduction Of Flii, The Atpase Specific For Flagellar Type Iii Secretion, Manabu Konishi, Masaomi Kanbe, Jonathan L. Mcmurry, Shin-Ichi Aizawa

Jonathan McMurry

The flagellar cytoplasmic ring (C ring), which consists of three proteins, FliG, FliM, and FliN, is located on the cytoplasmic side of the flagellum. The C ring is a multifunctional structure necessary for flagellar protein secretion, torque generation, and switching of the rotational direction of the motor. The deletion of any one of the fliG, fliM, and fliN genes results in a Fla - phenotype. Here, we show that the overproduction of the flagellum-specific ATPase FliI overcomes the inability of basal bodies with partial C-ring structures to produce complete flagella. Flagella made upon FliI overproduction were paralyzed, indicating that an intact ...


Effect Of Sulfur And Manure On Availability Of Rock Phosphate In Soil, P. E. Brown, A. R. Gwinn 2017 Iowa State College

Effect Of Sulfur And Manure On Availability Of Rock Phosphate In Soil, P. E. Brown, A. R. Gwinn

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The use of phosphorus fertilizers is now a recognized necessity in all systems of permanent agriculture. However well supplied naturally, all soils gradually become depleted in phosphorous thru the removal of crops and this element must be returned if crop production is to continue satisfactory. Many soils, especially those under long continued cultivation, have been found to respond very profitably to phosphorus fertilization while even the newer, more fertile soils are approaching a condition where phosphorus will soon become the controlling factor of growth. The interest in phosphorus fertilizers is therefore becoming more widespread and the use of these materials ...


Carbon Dioxide Production In Soils And Carbon And Nitrogen Changes In Soils Variously Treated, R. S. Potter, R. S. Snyder 2017 Iowa State College

Carbon Dioxide Production In Soils And Carbon And Nitrogen Changes In Soils Variously Treated, R. S. Potter, R. S. Snyder

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The carbon dioxide of the soil atmosphere, along with the water, has long been recognized as the most active agent in the decomposition of comparatively inert minerals to give available and soluble plant food material. It is probable that herein lies the great benefit which comes from the application to soil of organic material which not only increases the energy material easily available for the bacteria, but also improves the physical condition of the soil. This in turn increases bacterial activity, which gives rise to increased carbon dioxide production.

At the Iowa Agricultural Experiment Station, for some time past, both ...


Studies On The Numbers Of Bacteria In Milk Showing Various Changes, B. W. Hammer, R. H. Hix 2017 Iowa State College

Studies On The Numbers Of Bacteria In Milk Showing Various Changes, B. W. Hammer, R. H. Hix

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The relationship between bacteria and the changes that occur in milk has been recognized since the middle of the last century. Certain of the milk abnormalities are almost characteristic of micro-organisms while others, such as abnormal flavors and odors, quite commonly result from causes other than bacterial. Recently the dairy section of the Iowa Agricultural Experiment Station in working with samples of milk from various parts of the state found that milk sometimes received low flavor scores when the number of contained bacteria was exceedingly small, while samples with high flavor scores sometimes contained large numbers of bacteria. This suggested ...


Environmental Implications Of Francisella Tularensis Biofilms, Jeffrey J. Margolis '00 2017 Illinois Mathematics and Science Academy

Environmental Implications Of Francisella Tularensis Biofilms, Jeffrey J. Margolis '00

Jeffrey Margolis

Francisella tularensis survives in one of the widest environmental ranges of any pathogen. Numerous mammals and arthropod vectors are infected by this highly virulent organism. How this zoonotic pathogen persists outside of its many hosts remains unexplored. We aimed to examine how F. tularensis interacts with environmental surfaces, and hypothesized that biofilm formation may enable survival of this organism in nature. By understanding the role these surface-attached bacterial communities play in F. tularensis ecology, we hope to gain insight into the mechanisms of environmental persistence and transmission of this pathogen.

We identify chitin as a potential non-host niche for F ...


Microflora In The Cheek Pouches Of Ord's Kangaroo Rat (Dipodomys Ordii) From The Nebraska Sandhills, Devin M. Christensen 2017 University of Nebraksa Omaha

Microflora In The Cheek Pouches Of Ord's Kangaroo Rat (Dipodomys Ordii) From The Nebraska Sandhills, Devin M. Christensen

Student Research and Creative Activity Fair

The microflora living within the Ord’s kangaroo rat (Dipodymis ordii) cheek pouches has never been extensively studied before. Kangaroo rats use their cheek pouches to transport seeds and grasses in their mouths that they later store. It is predicted that the cheek pouches harbor fungal and bacterial growth that could be either helpful or harmful to the kangaroo rat and its environment. 8 kangaroo rats were humanely captured using Sherman live traps in the Nebraska Sandhills; their cheek pouches were swabbed, and the microorganisms obtained were grown on agar plates and in liquid media until an adequate amount of ...


Draft Genome Sequences Of Three Closely Related Isolates Of The Purple Nonsulfur Bacterium Rhodovulum Sulfidophilum, Michael S. Guzman, Beau McGinley, Natalia Santiago-Merced, Dinesh Gupta, Arpita Bose 2017 Washington University in St. Louis

Draft Genome Sequences Of Three Closely Related Isolates Of The Purple Nonsulfur Bacterium Rhodovulum Sulfidophilum, Michael S. Guzman, Beau Mcginley, Natalia Santiago-Merced, Dinesh Gupta, Arpita Bose

Biology Faculty Publications & Presentations

We report here the draft genome sequences of three isolates of Rhodovulum sulfidophilum from a single population that will serve as a model system for understanding genomic traits that underlie metabolic variation within closely related marine purple nonsulfur bacteria in natural microbial communities.


Evolutionary Adaptations Of Biofilms Infecting Cystic Fibrosis Lungs Promote Mechanical Toughness By Adjusting Polysaccharide Production, Kristin Kovach, Megan Davis-Fields, Yasuhiko Irie, Kanishk Jain, Shashvat Doorwar, Katherine Vuong, Numa Dhamani, Kishore Mohanty, Ahmed Touhami, Vernita D. Gordon 2017 University of Texas at Austin

Evolutionary Adaptations Of Biofilms Infecting Cystic Fibrosis Lungs Promote Mechanical Toughness By Adjusting Polysaccharide Production, Kristin Kovach, Megan Davis-Fields, Yasuhiko Irie, Kanishk Jain, Shashvat Doorwar, Katherine Vuong, Numa Dhamani, Kishore Mohanty, Ahmed Touhami, Vernita D. Gordon

Yasuhiko Irie

Biofilms are communities of microbes embedded in a matrix of extracellular polymeric substances, largely polysaccharides. Multiple types of extracellular polymeric substances can be produced by a single bacterial strain. The distinct polymer components of biofilms are known to provide chemical protection, but little is known about how distinct extracellular polysaccharides may also protect biofilms against mechanical stresses such as shear or phagocytic engulfment. Decades-long infections of Pseudomonas. aeruginosa biofilms in the lungs of cystic fibrosis patients are natural models for studies of biofilm fitness under pressure from antibiotics and the immune system. In cystic fibrosis infections, production of the extracellular ...


Relating Watershed Characteristics To Elevated Stream Escherichia Coli Levels In Agriculturally Dominated Landscapes: An Iowa Case Study, Conrad Brendel, Michelle L. Soupir 2017 Iowa State University

Relating Watershed Characteristics To Elevated Stream Escherichia Coli Levels In Agriculturally Dominated Landscapes: An Iowa Case Study, Conrad Brendel, Michelle L. Soupir

Agricultural and Biosystems Engineering Publications

Fecal Indicator Bacteria (FIB) such as Escherichia coli (E. coli) are a leading cause of surface water impairments in the United States. However, the relative impacts of different watershed characteristics on microbial water quality in agriculturally dominated watersheds are unclear. Spatial and statistical analyses were utilized to examine relationships between watershed characteristics and FIB and a multiple regression model was created. Geometric mean E. coli concentration data were obtained for 395 ambient water quality monitoring locations in Iowa. Watersheds were delineated for thirty randomly selected monitoring locations and drainage areas ranged from 93 to 1.1 million hectares. Watershed characteristics ...


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.


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