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Full-Text Articles in Biology

Darwin At The Drugstore? Testing The Biological Fitness Of Antibiotic Resistant Bacteria, Alan L. Gillen, Sarah Anderson Jul 2019

Darwin At The Drugstore? Testing The Biological Fitness Of Antibiotic Resistant Bacteria, Alan L. Gillen, Sarah Anderson

Alan L. Gillen

The issue of antibiotic resistance in bacteria is growing. For example, methicillin-resistant Staphylococcus aureus (MRSA) is a leading human pathogen. New strains of MRSA are resistant to methicillin and numerous other antibiotics, placing the patient in significant danger. Indeed, the Centers for Disease Control revealed in 2007 that the number of deaths due to MRSA exceeded that of AIDS in the United States. It is no wonder that antibiotic resistance is one of the most significant and important health care issues. The ability of bacterial pathogens to evade traditional antibiotics is faster than the drug makers’ ability to make new …


The Signature Of God In Medicine And Microbiology An Apologetic Argument For Declarative Design In The Discoveries Of Alexander Fleming, Alan L. Gillen, Michael Cargill Jun 2019

The Signature Of God In Medicine And Microbiology An Apologetic Argument For Declarative Design In The Discoveries Of Alexander Fleming, Alan L. Gillen, Michael Cargill

Alan L. Gillen

In logic and reasoning, a signature indicates the presence of an author; likewise, the characteristics of staphylococci indicate the presence of a Creator. Staphylococci and its “kind” are common bacteria, particularly in colonized people.1 Staphylococcus aureus has a complex molecular mechanism of assembling its golden pigment, staphyloxanthin. The biosynthesis of staphyloxanthin is a stellar example of irreducible complexity. Similar to staphylococci, the life and works of Alexander Fleming show the fingerprints of Providence. The so-called “serendipitous” achievements of Fleming have contributed to modern medicine, convincing Fleming and others that God was at work in his life. Fleming recognized that …


Mechanisms Responsible For A Φx174 Mutant's Ability To Infect Escherichia Coli By Phosphorylation, Jennifer Cox, Catherine Putonti Sep 2017

Mechanisms Responsible For A Φx174 Mutant's Ability To Infect Escherichia Coli By Phosphorylation, Jennifer Cox, Catherine Putonti

Catherine Putonti

The ability for a virus to expand its host range is dependent upon a successful mode of viral entry. As such, the host range of the well-studied ΦX174 bacteriophage is dictated by the presence of a particular lipopolysaccharide (LPS) on the bacterial surface. The mutant ΦX174 strain JACS-K, unlike its ancestor, is capable of infecting both its native host Escherichia coli C and E. coli K-12, which does not have the necessary LPS. The conversion of an alanine to a very reactive threonine on its virion surface was found to be responsible for the strain's expanded host range.


Assessment Of A Metaviromic Dataset Generated From Nearshore Lake Michigan, Siobhan C. Watkins, Neil Kuehnle, C Anthony Ruggeri, Kema Malki, Katherine Bruder, Jinan Elayyan, Kristina Damisch, Naushin Vahora, Paul O'Malley, Brianne Ruggles-Sage, Zachary Romer, Catherine Putonti Sep 2017

Assessment Of A Metaviromic Dataset Generated From Nearshore Lake Michigan, Siobhan C. Watkins, Neil Kuehnle, C Anthony Ruggeri, Kema Malki, Katherine Bruder, Jinan Elayyan, Kristina Damisch, Naushin Vahora, Paul O'Malley, Brianne Ruggles-Sage, Zachary Romer, Catherine Putonti

Catherine Putonti

Bacteriophages are powerful ecosystem engineers. They drive bacterial mortality rates and genetic diversity, and affect microbially mediated biogeochemical processes on a global scale. This has been demonstrated in marine environments; however, phage communities have been less studied in freshwaters, despite representing a potentially more diverse environment. Lake Michigan is one of the largest bodies of freshwater on the planet, yet to date the diversity of its phages has yet to be examined. Here, we present a composite survey of viral ecology in the nearshore waters of Lake Michigan. Sequence analysis was performed using a web server previously used to analyse …


Communities Of Cloacal Bacteria In Tree Swallow Families, Michael Lombardo, Patrick Thorpe, R. Cichewicz, M. Henshaw, C. Millard, C. Steen, T. Zeller Jul 2010

Communities Of Cloacal Bacteria In Tree Swallow Families, Michael Lombardo, Patrick Thorpe, R. Cichewicz, M. Henshaw, C. Millard, C. Steen, T. Zeller

Michael P Lombardo

Our aim in this study was to survey the communities of bacteria found in the cloacae of adult and nestling Tree Swallows (Tachycineta bicolor), determine if there were familial patterns of prevalence, and determine if there were relationships between bacteria loads and nestling size when 12 days old and fledging success.


Bactericidal Efficacy Of Liposomal Aminoglycosides Against Burkholderia Cenocepacia, Ali Azghani Jul 2007

Bactericidal Efficacy Of Liposomal Aminoglycosides Against Burkholderia Cenocepacia, Ali Azghani

Ali Azghani

Objectives Burkholderia cenocepacia (formally a genotype of Burkholderia cepacia complex called genomovar III) has emerged as a serious opportunistic pathogen in individuals with cystic fibrosis. We developed a liposomal antibiotic formulation composed of 1,2-distearoyl-sn-glycero-3-phosphocholine and cholesterol (molar ratio 2:1) to overcome B. cenocepacia's resistance to commonly used aminoglycosidic antibiotics.
Methods The dehydration-rehydration vesicles technique was used to entrap antibiotics in liposomes. The size of liposome formulations was measured and encapsulation efficiencies were determined by microbiological assays. MICs of free and liposomal antibiotics against the clinical isolates of B. cenocepacia were determined by the standard broth …


Mechanisms For Soil Moisture Effects On Activity Of Nitrifying Bacteria, John M. Stark, M. K. Firestone Jan 1995

Mechanisms For Soil Moisture Effects On Activity Of Nitrifying Bacteria, John M. Stark, M. K. Firestone

John M. Stark

Moisture may limit microbial activity in a wide range of environments including salt water, food, wood, biofilms, and soils. Low water availability can inhibit microbial activity by lowering intracellular water potential and thus reducing hydration and activity of enzymes. In solid matrices, low water content may also reduce microbial activity by restricting substrate supply. As pores within solid matrices drain and water films coating surfaces become thinner, diffusion path lengths become more tortuous, and the rate of substrate diffusion to microbial cells declines. We used two independent techniques to evaluate the relative importance of cytoplasmic dehydration versus diffusional limitations in …