Density gradient ultracentrifugation of low density lipoproteins (LDL) from 12 normal subjects showed multiple, distinct isopycnic bands.Densitometric scanning the tubes revealed that each band could be assigned to one four intervals and boundaries these were consistent among all subjects.Analytic ultracentrifuge flo- tation (Sp) rates intervals, there was a strong correlation between peak Sp rate ' Burke, D.

Soil ecologists have debated the relative importance of dispersal limitation and ecological factors in determining structure soil microbial communities. Recent evidence suggests that ‘everything is not everywhere’, communities are influenced by both factors. However, we still do understand explanatory power spatial factors, including plant species identity even relatedness, for different fractions community (i.e. bacterial fungal communities). To ask whether such as species, chemistry,...

In this study, we investigated the effect of positively and negatively charged Fe3O4 TiO2 nanoparticles (NPs) on growth soybean plants (Glycine max.) their root associated soil microbes. Soybean were grown in a greenhouse for six weeks after application different amounts NPs, plant nutrient content examined. Roots analyzed colonization by arbuscular mycorrhizal (AM) fungi nodule-forming nitrogen fixing bacteria using DNA-based techniques. We found that was significantly lower with as...

Summary Feedbacks between soil communities and plants may determine abundance diversity in plant by influencing fitness competitive outcomes. We tested the core hypotheses of community feedback theory: species culture distinct that alter performance outcome interspecific competition. applied this framework to inform repeated dominance S olidago canadensis old‐field communities. In glasshouse experiments, we examined effects on four species' monoculture outcomes used terminal restriction...

Many forests are affected by chronic acid deposition, which can lower soil pH and limit the availability of nutrients such as phosphorus (P), but response mycorrhizal fungi to changes in P how this affects tree acquisition is not well understood. Here, we describe an ecosystem-level manipulation 72 plots, increased and/or across six Ohio, USA. Two years after treatment initiation, on roots were examined with molecular techniques, including 454-pyrosequencing. Elevating significantly...

ABSTRACT The interactions among Spartina patens and sediment microbial populations the Phragmites australis were studied at monotypic sites in Piermont Marsh, a salt marsh of Hudson River north New York, N.Y., key times during growing season. Arbuscular mycorrhizal fungi (AMF) effectively colonized S. but not P. , there seasonal increases decreases that coincided with plant growth senescence (17 6% root length colonized, respectively). In samples from site, community specific bacterial least...

The transcription efficiencies of four Drosophila tRNAArg genes located in a tRNA gene cluster at region 42A on chromosome 2, and containing identical coding sequences, were studied Kc cell extracts. Transcription is modulated by the 5' flanking sequences; efficient dependent presence an optimal sequence. One genes, p17D Arg, not transcribed homologous extract but does compete with other for factors. Deletion specific sequence from flank Arg leads to increase efficiency. All are efficiently...

Many temperate forests of the Northeastern United States and Europe have received significant anthropogenic acid nitrogen (N) deposition over last century. Although hardwood are generally thought to be N-limited, increases possibility phosphorus (P) limiting productivity in these forest ecosystems. Moreover, inorganic P availability is largely controlled by soil pH biogeochemical theory suggests that with acidic soils (i.e., <pH 5) particularly vulnerable limitation. Results from previous...

Abstract Symptoms of beech leaf disease (BLD), first reported in Ohio 2012, include interveinal greening, thickening and often chlorosis leaves, canopy thinning mortality. Nematodes from diseased leaves American ( Fagus grandifolia ) sent by the Department Agriculture to USDA, Beltsville, MD autumn 2017 were identified as recorded North population Litylenchus crenatae Nematology , 21, 2019, 5), originally described Japan. This other populations Ohio, Pennsylvania neighbouring province...

The 23-kDa recombinant amino-terminal bactericidal/permeability increasing protein fragment (rBPI23) has all of the antibacterial and antiendotoxin properties holoprotein. In current studies, we have identified multiple active domains within rBPI23 with chemical proteolytic cleavage fragments synthetic overlapping peptides. We also demonstrate a novel, high affinity heparin binding property for rBPI23, in addition to its established bactericidal lipopolysaccharide properties. Cleavage...

Herbaceous plant species are important components of forest ecosystems, and their persistence in forests may be affected by invasive that reduce mycorrhizal colonization roots. I examined the effect Alliaria petiolata on arbuscular fungi (AMF) colonizing roots three species. AMF root community structure was from plants were growing either absence or presence under natural conditions. varied among but not significantly Alliaria. With molecular methods, ∼12 different taxa could distinguished...

ABSTRACT Although the level of diversity root-associated fungi can be quite high, effect plant distribution and soil environment on fungal communities at fine spatial scales has received little attention. Here, we examine how affect occurrence, diversity, community structure local patch within a mature forest. We used terminal restriction fragment length polymorphism sequence analysis to detect 63 species representing 28 different genera colonizing tree root tips. At least 32 matched...

We have examined the 5'-and 3'-flanking sequence requirements for wild type transcription properties of a Drosophila tRNA Arg gene through use assays in cell-free extracts. Thirty-three base pairs 5' flank immediately adjacent to encoding mature are necessary efficient Kc cell extract. Sequences affecting factor binding form stable complexes extend more than 60 into flank, and approximately 35 3' flank. HeLa extract exhibits dependence, albeit reduced, on same 5'-flanking sequence; it also...

Trypsin digestion of Hansenula wingei 21-cells releases a protein (21-factor-T) that inhibits the agglutination by purified 5-agglutinin obtained from 5-cells subtilisin [Crandall, M. A. &amp; Brock, T. D. (1968) Bacteriol. Rev. 32, 139-163]. We have this inhibitor 415-fold ion-exchange chromatography, affinity adsorption to 5-cells, and gel permeation chromatography. The material shows diffuse band, on polyacrylamide electrophoresis in presence sodium dodecyl sulfate, with an apparent M r...

We studied the effect of ectomycorrhizal fungi on bacterial communities colonizing roots Douglas fir (Pseudotsuga menziesii). Mycorrhizal tips were cleaned soil and separated based gross morphological characteristics. Sequencing internal transcribed spacers nuclear rRNA gene cluster indicated that majority colonized by in Russulaceae, with genera Russula Lactarius comprising 70% tips. Because coamplification organellar 16S genes can interfere community analysis root tips, we developed tested...

Abstract American beech ( Fagus grandifolia ) is the target of a newly emerging disease in North America called leaf (BLD) that affects and disfigures leaves which can lead to tree mortality. Beech may be caused by recognized subspecies anguinid nematode Litylenchus crenatae subsp. mccannii , but associations this with bacterial fungal taxa are unknown. We examined microbial communities associated affected BLD 16‐year‐old plantation using molecular methods. detected L. anywhere from 45% 90%...

Abstract Forest ecosystems with altered nutrient limitations are a common legacy of acidic deposition in North America. Continued has lowered soil pH and revealed phosphorus (P) many temperate forest ecosystems. Previous studies exploring P or co‐limitations often short term, thus may potentially show response to limitation that is not sustained over time. To better understand how forest's can change time, we added P, limestone raise pH, cross‐treatment where both were 3 different...