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Full-Text Articles in Life Sciences
Community Metabolism And Nutrient Cycling In The Mississippi River Plume: Evidence For Intense Nitrification At Intermediate Salinities, Joseph D. Pakulski, Ronald Benner, Rainer Amon, Brian Eadie, Terry Whitledge
Community Metabolism And Nutrient Cycling In The Mississippi River Plume: Evidence For Intense Nitrification At Intermediate Salinities, Joseph D. Pakulski, Ronald Benner, Rainer Amon, Brian Eadie, Terry Whitledge
Faculty Publications
Community respiration, net nutrient fluxes and heterotrophic bacterial production were investigated in the Mississippi River (USA) plume during May 1992 using dark bottle incubations of unfiltered water. Highest rates of community O2 consumption and dissolved inorganic carbon regeneration were observed at intermediate (10 to 27%0) plume salinities. Plume surface 02 consumption rates were 2- to 4-fold greater than rates reported previously during the summer and winter. Heterotrophic bacterial production ([3H]-leucine incorporation) was also highest at intermediate salinities and 2- to 4-fold greater than rates reported from other seasons. Net regeneration of NH4+ …
Mechanisms For Soil Moisture Effects On Activity Of Nitrifying Bacteria, John M. Stark, M. K. Firestone
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 …
Mechanisms For Soil Moisture Effects On Activity Of Nitrifying Bacteria, John M. Stark, M. K. Firestone
Mechanisms For Soil Moisture Effects On Activity Of Nitrifying Bacteria, John M. Stark, M. K. Firestone
Biology Faculty Publications
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 …
In Vitro Activity Of Four Fluoroquinolones On Selected Bacteria, Sheryl L. Pullen
In Vitro Activity Of Four Fluoroquinolones On Selected Bacteria, Sheryl L. Pullen
University of the Pacific Theses and Dissertations
In 1990-1991, in a national surveillance study, and in 1991-1992, in a followup study, both by Thornsberry et al. (1993), ciprofloxacin data from various geographical and demographical institutions were collected. Several species of bacteria have shown resistance to ciprofloxacin and norfloxacin, but the degree of resistance to these drugs has not been reported for the Stockton area. To determine the extent of this resistance, Dameron Hospital antibiograms generated from 1990 to 1994 were reviewed and compared. Results of the comparison show that susceptibility among the Gram-negative isolates, with the exception of Providencia stuartii, Acinetobacter lwoffi, and to a lesser extent …