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Full-Text Articles in Biology
Isolation Of Three Hexahydro-1,3,5-Trinitro-1,3,5-Triazine- Degrading Species Of The Family Enterobacteriaceae From Nitramine Explosive-Contaminated Soil, Christopher Kitts, Daryl P. Cunningham, Pat J. Unkefer
Isolation Of Three Hexahydro-1,3,5-Trinitro-1,3,5-Triazine- Degrading Species Of The Family Enterobacteriaceae From Nitramine Explosive-Contaminated Soil, Christopher Kitts, Daryl P. Cunningham, Pat J. Unkefer
Biological Sciences
Three species of the family Enterobacteriaceae that biochemically reduced hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) were isolated from nitramine explosive-contaminated soil. Two isolates, identified as Morganella morganii and Providencia rettgeri, completely transformed both RDX and the nitroso-RDX reduction intermediates. The third isolate, identified as Citrobacter freundii, partially transformed RDX and generated high concentrations of nitroso-RDX intermediates. All three isolates produced 14CO2 from labeled RDX under O2-depleted culture conditions. While all three isolates transformed HMX, only M. morganii transformed HMX in the presence of RDX.
Review Of Survival, Reproduction, And Behavior By J.R. Krebs And N.B. Davies, Marlene Zuk, Torgeir S. Johnsen, Gita R. Kolluru, Kurt A. Mckean, Bradd Schulke
Review Of Survival, Reproduction, And Behavior By J.R. Krebs And N.B. Davies, Marlene Zuk, Torgeir S. Johnsen, Gita R. Kolluru, Kurt A. Mckean, Bradd Schulke
Biological Sciences
No abstract provided.
The Role Of Enzyme Activation State In Limiting Carbon Assimilation Under Variable Light Conditions, Gretchen F. Sassenrath-Cole, Robert W. Pearcy, Scott J. Steinmaus
The Role Of Enzyme Activation State In Limiting Carbon Assimilation Under Variable Light Conditions, Gretchen F. Sassenrath-Cole, Robert W. Pearcy, Scott J. Steinmaus
Biological Sciences
The mechanisms regulating transient photosynthesis by soybean (Glycine max) leaves were examined by comparing photosynthetic rates and carbon reduction cycle enzyme activities under flashing (saturating 1 s lightflecks separated by low photon flux density (PFD) periods of different durations) and continuous PFD. At the same mean PFD, the mean photosynthetic rates were reduced under flashing as compared to continuous light. However, as the duration of the low PFD period lengthened, the CO2 assimilation attributable to a lightfleck increased. This enhanced lightfleck CO2 assimilation was accounted for by a greater postillumination CO2 fixation occurring after the …
Disparate Rates Of Molecular Evolution In Cospeciating Hosts And Parasites, M. S. Hafner, P. D. Sudman, F. X. Villablanca, T. A. Spradling, J. W. Demastes, S. A. Nadler
Disparate Rates Of Molecular Evolution In Cospeciating Hosts And Parasites, M. S. Hafner, P. D. Sudman, F. X. Villablanca, T. A. Spradling, J. W. Demastes, S. A. Nadler
Biological Sciences
DNA sequences for the gene encoding mitochondrial cytochrome oxidase I in a group of rodents (pocket gophers) and their ectoparasites (chewing lice) provide evidence for cospeciation and reveal different rates of molecular evolution in the hosts and their parasites. The overall rate of nucleotide substitution (both silent and replacement changes) is approximately three times higher in lice, and the rate of synonymous substitution (based on analysis of fourfold degenerate sites) is approximately an order of magnitude greater in lice. The difference in synonymous substitution rate between lice and gophers correlates with a difference of similar magnitude in generation times.
Azorhizobium Caulinodans Respires With At Least Four Terminal Oxidases, Christopher Kitts, Robert A. Ludwig
Azorhizobium Caulinodans Respires With At Least Four Terminal Oxidases, Christopher Kitts, Robert A. Ludwig
Biological Sciences
In culture, Azorhizobium caulinodans used at least four terminal oxidases, cytochrome aa3 (cytaa3), cytd, cyto, and a second a-type cytochrome, which together mediated general, respiratory electron (e-) transport to O2. To genetically dissect physiological roles for these various terminal oxidases, corresponding Azorhizobium apocytochrome genes were cloned, and three cytaa3 mutants, a cytd mutant, and a cytaa3, cytd double mutant were constructed by reverse genetics. These cytochrome oxidase mutants were tested for growth, oxidase activities, and N2 fixation properties both …
Impalement Of Marine Turtles (Reptilia, Chelonia: Cheloniidae And Dermochelyidae) By Billfishes (Osteichthyes, Perciformes: Istiophoridae And Xiphiidae), John G. Frazier, Harry L. Fierstine, Sallie C. Beavers, Federico Achaval, Hiroyuki Suganuma, Robert L. Pitman, Yuichiro Yamaguchi, Carlos Ma. Prigioni
Impalement Of Marine Turtles (Reptilia, Chelonia: Cheloniidae And Dermochelyidae) By Billfishes (Osteichthyes, Perciformes: Istiophoridae And Xiphiidae), John G. Frazier, Harry L. Fierstine, Sallie C. Beavers, Federico Achaval, Hiroyuki Suganuma, Robert L. Pitman, Yuichiro Yamaguchi, Carlos Ma. Prigioni
Biological Sciences
Billfishes have long been known to impale a great variety of objects, but there are only two brief, obscure records of marine turtles being speared. Details are presented on these two, as well as on two other confirmed records; data from two additional unconfirmed records are also presented. In total, three species of marine turtles are known to have been impaled by three species of billfishes; a fourth species of fish and a fourth species turtle are listed in an unconfirmed case. Records come from the eastern and western Pacific as well as the eastern Atlantic. Of the four confirmed …
Icecolors '93: Biological Weighting Function For The Ultraviolet Inhibition Of Carbon Fixation In A Natural Antarctic Phytoplankton Community, Nicholas Boucher, Barbara B. Prezelin, T. Evens, R. Jovine, B. Kroon, Mark A. Moline, Oscar Schofield
Icecolors '93: Biological Weighting Function For The Ultraviolet Inhibition Of Carbon Fixation In A Natural Antarctic Phytoplankton Community, Nicholas Boucher, Barbara B. Prezelin, T. Evens, R. Jovine, B. Kroon, Mark A. Moline, Oscar Schofield
Biological Sciences
No abstract provided.
Palmer Lter: Impact Of A Large Diatom Bloom On Macronutrient Distribution In Arthur Harbor During Austral Summer 1991-1992, Mark A. Moline, Barbara B. Prezelin
Palmer Lter: Impact Of A Large Diatom Bloom On Macronutrient Distribution In Arthur Harbor During Austral Summer 1991-1992, Mark A. Moline, Barbara B. Prezelin
Biological Sciences
No abstract provided.
Palmer Lter: Photoadaptation In A Coastal Phytoplankton Bloom And Impact On The Radiation Utilization Efficiency For Carbon Fixation, Oscar Schofield, Barbara B. Prezelin, Mark A. Moline
Palmer Lter: Photoadaptation In A Coastal Phytoplankton Bloom And Impact On The Radiation Utilization Efficiency For Carbon Fixation, Oscar Schofield, Barbara B. Prezelin, Mark A. Moline
Biological Sciences
No abstract provided.
Spatial And Temporal Aspects Of Populations Revealed By Mitochondrial Dna, Francis X. Villablanca
Spatial And Temporal Aspects Of Populations Revealed By Mitochondrial Dna, Francis X. Villablanca
Biological Sciences
The evolutionary analysis of DNA sequences bridges phylogenetics and population genetics. Ancient DNA (aDNA) alJows the study of extinct genotypes, populations, and species, as well as dichronic comparisons of extant populations and species. Thus a DNA forges an empirical link between history and two inherently historical fields of research. Fortunately, the conceptual frameworks of phylogenetics and population genetics can easily be extended to encompass advances being made in the study of aDNA.