Synthesis and biological activity of anticoccidial agents: 2,3-diarylindoles

Novel 2,3-diarylindoles bearing an amine substituent at the indole 5- and 6-positions have been synthesized and evaluated as anticoccidial agents in both in vitro and in vivo assays. Both subnanomolar in vitro activity and broad spectrum in vivo potency were detected for several compounds, particularly compound 27.     

Association study and expression analysis of porcine ESR1 as a candidate gene for boar fertility and sperm quality

Male fertility is impaired through the lack of ESR1 (Estrogen Receptor 1) but little is known about the ESR1 roles in boar spermatogenesis and fertility. Therefore, this research was aimed at investigating the association with sperm quality and boar fertility traits in a total of 300 boars both from purebred Pietrain and Pietrain × Hampshire crosses. A SNP in coding region of ESR1g.672C>T in exon 1 was associated with sperm motility (P<0.05) and plasma droplet rate (P<0.01) while the polymorphism in non-coding region of ESR1g.35756T>C in inton 1 was associated with non-return rate (P<0.05). Furthermore, to analyse the mRNA and protein expression of ESR1 in boar reproductive tissues, a total of six boars were divided into two groups [Group I (G-I) and Group II (G-II)], where G-I had relatively better sperm quality. ESR1 expression was higher in tissues collected from G-I boars than those of collected from G-II boars, and the difference in mRNA expression was significant (P<0.01) in head of epididymis. The ESR1 protein expression results from western blot coincided with the results of qRT-PCR. The ESR1 protein localization observed a strong staining in the cytoplasm of Sertoli cell in the testis, in the epithelial cells in head and tail of epididymis, in smooth muscle in tail of epididymis, and in the post acrosomal region and tail of the spermatozoa. These results will improve the understanding of the functions of the ESR1 in spermatogenesis within the reproductive tract and will shed light on ESR1 as a candidate in the selection of boar with good sperm quality and fertility.     

Malate plays a central role in plant nutrition

Malate occupies a central role in plant metabolism. Its importance in plant mineral nutrition is reflected by the role it plays in symbiotic nitrogen fixation, phosphorus acquisition, and aluminum tolerance. In nitrogen-fixing root nodules, malate is the primary substrate for bacteroid respiration, thus fueling nitrogenase. Malate also provides the carbon skeletons for assimilation of fixed nitrogen into amino acids. During phosphorus deficiency, malate is frequently secreted from roots to release unavailable forms of phosphorus. Malate is also involved with plant adaptation to aluminum toxicity. To define the genetic and biochemical regulation of malate formation in plant nutrition we have isolated and characterized genes involved in malate metabolism from nitrogen-fixing root nodules of alfalfa and those involved in organic acid excretion from phosphorus-deficient proteoid roots of white lupin. Moreover, we have overexpressed malate dehydrogenase in alfalfa in attempts to improve nutrient acquisition. This report is an overview of our efforts to understand and modify malate metabolism, particularly in the legumes alfalfa and white lupin.     

Horizon-Specific Bacterial Community Composition of German Grassland Soils,as Revealed by Pyrosequencing-Based Analysis of 16S rRNA Genes

The diversity of bacteria in soil is enormous, and soil bacterial communities can vary greatly in structure. Here, we employed a pyrosequencing-based analysis of the V2-V3 16S rRNA gene region to characterize the overall and horizon-specific (A and B horizons) bacterial community compositions in nine grassland soils, which covered three different land use types. The entire data set comprised 752,838 sequences, 600,544 of which could be classified below the domain level. The average number of sequences per horizon was 41,824. The dominant taxonomic groups present in all samples and horizons were the Acidobacteria, Betaproteobacteria, Actinobacteria, Gammaproteobacteria, Alphaproteobacteria, Deltaproteobacteria, Chloroflexi, Firmicutes, and Bacteroidetes. Despite these overarching dominant taxa, the abundance, diversity, and composition of bacterial communities were horizon specific. In almost all cases, the estimated bacterial diversity (H′) was higher in the A horizons than in the corresponding B horizons. In addition, the H′ was positively correlated with the organic carbon content, the total nitrogen content, and the C-to-N ratio, which decreased with soil depth. It appeared that lower land use intensity results in higher bacterial diversity. The majority of sequences affiliated with the Actinobacteria, Bacteroidetes, Cyanobacteria, Fibrobacteres, Firmicutes, Spirochaetes, Verrucomicrobia, Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria were derived from A horizons, whereas the majority of the sequences related to Acidobacteria, Chloroflexi, Gemmatimonadetes, Nitrospira, TM7, and WS3 originated from B horizons. The distribution of some bacterial phylogenetic groups and subgroups in the different horizons correlated with soil properties such as organic carbon content, total nitrogen content, or microbial biomass.Soil is probably the most complex microbial environment on Earth with respect to species richness and community size. The microbial richness in soils exceeds that of other environments (44) and is higher by orders of magnitude than the biodiversity of plants and animals. Cultivated soil or grassland soil contains an estimated 2 × 10⁹ prokaryotic cells per gram (12). Soil microbial communities are an important factor of agriculturally managed systems, as they are responsible for most nutrient transformations in soil and influence the above-ground plant diversity and productivity (53).To analyze the bacterial community in soils, most approaches target the 16S rRNA gene by PCR amplification and subsequent analysis employing sequencing of clone libraries (10, 24), denaturing gradient gel electrophoresis (DGGE) (38), or terminal restriction fragment length polymorphism (T-RFLP) (17, 52). Most of these approaches provided limited insights into the structure of soil bacterial communities, as the survey sizes and the number of compared sampling sites were small with respect to the enormous bacterial diversity present in different soil samples. For example, the reported clone libraries vary considerably in size, but small sample sizes (500 or fewer 16S rRNA gene sequences) are usually analyzed and employed for the theoretical estimation of species richness (39). This provides snapshots of the predominant bacterial community members, but phylogenetic groups that are present in a low abundance and which may possess important ecosystem functions are not assessed (47). In addition, it has been shown that rich sampling (several thousands of clones) of complex bacterial communities is required to perform robust measurements and estimations of community diversity parameters (37). Thus, the detection bias accompanying analyses of small sample sizes can lead to invalidated assumptions. Genetic profiling techniques such as DGGE and T-RFLP have high-throughput capability. These approaches allow researchers to unravel differences in community structure but are limited for assessing diversity (23, 40). To deeply survey the diversity and the composition of the bacterial communities within different soil samples, large-scale pyrosequencing of partial 16S rRNA genes has been employed recently. Previous pyrosequencing-based studies of soil (1, 30, 34, 43) have generated large data sets, which comprised 39,707 (30) to 152,359 (34) 16S rRNA partial gene sequences. Those studies provided comprehensive insights into the biogeography of bacterial soil communities and taxa that were present in a low abundance. However, all those studies focused on the analysis of microbial communities present in topsoil. The subsoil is also known to harbor an important part of the soil microbial biomass (18). It has been shown that the microbial population in the shallow subsurface is impacted by agricultural production to a similar extent as that in topsoil (5).In this study, we performed large-scale pyrosequencing-based analyses of 16S rRNA genes to assess the bacterial community composition in topsoil and the corresponding subsoil of nine different grassland sites in the Hainich region (Thuringia, Germany). To provide a high level of coverage at the species level (97% genetic distance) and minimize detection bias, we exceeded the above-described numbers of analyzed 16S rRNA gene sequences (752,838 in this study). To examine the impact of land use on bacterial diversity and community composition, the selected grassland sites covered a range of three different land use types, including samples from unfertilized pastures grazed by cattle, fertilized mown pastures grazed by cattle, and fertilized meadows. In many recent studies, surveys were focused on comprehensive analyses of a single soil or a few soil samples (1, 14, 37, 43). This allowed the determination of overall bacterial species richness and community composition, but the assessment of spatial patterns and environmental factors that drive these patterns is hampered by the limited number of examined soils. To assess spatial distribution and the impact of soil edaphic factors and land use on community structure, we used triplicate samples of each land use type from different locations. In addition, composite samples derived from five soil cores after the separation of soil horizons were employed.     

Hydroxylated N-alkyl-4-piperidinyl-2,3-diarylpyrrole derivatives as potent broad-spectrum anticoccidial agents

Diaryl-(4-piperidinyl)-pyrrole derivatives bearing hydroxylated N-alkyl substituents have been synthesized and evaluated as anticoccidial agents. High potency in Et-PKG inhibition and broad-spectrum anticoccidial activities have been observed on compounds, such as 4b and 5h, which are fully efficacious in vivo at 50 ppm in feed.     

Effects of long‐term differential fertilization on eukaryotic microbial communities in an arable soil: a multiple barcoding approach

To understand the fine‐scale effects of changes in nutrient availability on eukaryotic soil microorganisms communities, a multiple barcoding approach was used to analyse soil samples from four different treatments in a long‐term fertilization experiment. We performed PCR amplification on soil DNA with primer pairs specifically targeting the 18S rRNA genes of all eukaryotes and three protist groups (Cercozoa, Chrysophyceae‐Synurophyceae and Kinetoplastida) as well as the ITS gene of fungi and the 23S plastid rRNA gene of photoautotrophic microorganisms. Amplicons were pyrosequenced, and a total of 88 706 quality filtered reads were clustered into 1232 operational taxonomic units (OTU) across the six data sets. Comparisons of the taxonomic coverage achieved based on overlapping assignment of OTUs revealed that half of the eukaryotic taxa identified were missed by the universal eukaryotic barcoding marker. There were only little differences in OTU richness observed between organic‐ (farmyard manure), mineral‐ and nonfertilized soils. However, the community compositions appeared to be strongly structured by organic fertilization in all data sets other than that generated using the universal eukaryotic 18S rRNA gene primers, whereas mineral fertilization had only a minor effect. In addition, a co‐occurrence based network analysis revealed complex potential interaction patterns between OTUs from different trophic levels, for example between fungivorous flagellates and fungi. Our results demonstrate that changes in pH, moisture and organic nutrients availability caused shifts in the composition of eukaryotic microbial communities at multiple trophic levels.     

Active hexose correlated compound enhances resistance to Klebsiella pneumoniae infection in mice in the hindlimb-unloading model of spaceflight conditions.

Previous studies have demonstrated that resistance to infection is decreased in Swiss Webster female mice maintained in the hindlimb-unloading model (Aviles H, Belay T, Fountain K, Vance M, and Sonnenfeld G. J Appl Physiol 95: 73-80, 2003; Belay T, Aviles H, Vance M, Fountain K, and Sonnenfeld G. J Allergy Clin Immunol 110: 262-268, 2002). This is a model of some of the aspects of spaceflight conditions, including lack of load bearing on hindlimbs and a fluid shift to the head. Active hexose correlated compound (AHCC), extracted from Basidiomycete mushrooms, has been shown to induce enhancement of immune responses, including enhanced natural killer activity. In the present study, AHCC was orally administered to mice to determine whether the treatment could decrease immunosuppression and mortality of mice maintained in the hindlimb-unloaded model and infected with Klebsiella pneumoniae. The results of the present study showed that administration of AHCC by gavage for 1 wk (1 g/kg body wt) before suspension and throughout the 10-day suspension period yielded significant beneficial effects for the hindlimb-unloaded group, including 1). decreased mortality, 2). increased time to death, and 3). increased ability to clear bacteria. The results suggest that AHCC can decrease the deleterious effects of the hindlimb-unloading model on immunity and resistance to infection.