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991.
Shaun J. Clare Nathan A. Wyatt Robert S. Brueggeman Timothy L. Friesen 《Molecular Plant Pathology》2020,21(2):272-288
Pyrenophora teres f. teres and P. teres f. maculata are significant pathogens that cause net blotch of barley. An increased number of loci involved in P. teres resistance or susceptibility responses of barley as well as interacting P. teres virulence effector loci have recently been identified through biparental and association mapping studies of both the pathogen and host. Characterization of the resistance/susceptibility loci in the host and the interacting effector loci in the pathogen will provide a path for targeted gene validation for better-informed release of resistant barley cultivars. This review assembles concise consensus maps for all loci published for both the host and pathogen, providing a useful resource for the community to be used in pathogen characterization and barley breeding for resistance to both forms of P. teres. 相似文献
992.
Two new antibacterial thiodiketopiperazine derivatives (TDKPs), 7‐dehydroxyepicoccin H and 7‐hydroxyeutypellazine F, along with seven known TDKP analogs, were isolated and identified from Epicoccum nigrum SD‐388, a deep‐sea‐sediment‐derived fungus. The structures of these compounds were elucidated on the basis of detailed spectroscopic analysis. The absolute configuration of 7‐dehydroxyepicoccin H was established by X‐ray crystallographic analysis, while 7‐hydroxyeutypellazine F was determined by ECD experiment and TDDFT‐ECD calculation. The antibacterial activities against human and aquatic pathogens were evaluated. 7‐Dehydroxyepicoccin H and 7‐hydroxyeutypellazine F displayed inhibitory activities against aquatic pathogens Vibrio vulnificus, V. alginolyticus, and Edwardsiella tarda, with MIC values ranging from 4.0 to 8.0 μg/mL. 相似文献
993.
The gut microorganisms in some animals are reported to include a core microbiota of consistently associated bacteria that is ecologically distinctive and may have coevolved with the host. The core microbiota is promoted by positive interactions among bacteria, favoring shared persistence; its retention over evolutionary timescales is evident as congruence between host phylogeny and bacterial community composition. This study applied multiple analyses to investigate variation in the composition of gut microbiota in drosophilid flies. First, the prevalence of five previously described gut bacteria (Acetobacter and Lactobacillus species) in individual flies of 21 strains (10 Drosophila species) were determined. Most bacteria were not present in all individuals of most strains, and bacterial species pairs co-occurred in individual flies less frequently than predicted by chance, contrary to expectations of a core microbiota. A complementary pyrosequencing analysis of 16S rRNA gene amplicons from the gut microbiota of 11 Drosophila species identified 209 bacterial operational taxonomic units (OTUs), with near-saturating sampling of sequences, but none of the OTUs was common to all host species. Furthermore, in both of two independent sets of Drosophila species, the gut bacterial community composition was not congruent with host phylogeny. The final analysis identified no common OTUs across three wild and four laboratory samples of D. melanogaster. Our results yielded no consistent evidence for a core microbiota in Drosophila. We conclude that the taxonomic composition of gut microbiota varies widely within and among Drosophila populations and species. This is reminiscent of the patterns of bacterial composition in guts of some other animals, including humans. 相似文献
994.
Leanne E. Lewis Judith M. Bain Blessing Okai Neil A.R. Gow Lars Peter Erwig 《Journal of visualized experiments : JoVE》2013,(71)
Phagocytic clearance of fungal pathogens, and microorganisms more generally, may be considered to consist of four distinct stages: (i) migration of phagocytes to the site where pathogens are located; (ii) recognition of pathogen-associated molecular patterns (PAMPs) through pattern recognition receptors (PRRs); (iii) engulfment of microorganisms bound to the phagocyte cell membrane, and (iv) processing of engulfed cells within maturing phagosomes and digestion of the ingested particle. Studies that assess phagocytosis in its entirety are informative1, 2, 3, 4, 5 but are limited in that they do not normally break the process down into migration, engulfment and phagosome maturation, which may be affected differentially. Furthermore, such studies assess uptake as a single event, rather than as a continuous dynamic process. We have recently developed advanced live-cell imaging technologies, and have combined these with genetic functional analysis of both pathogen and host cells to create a cross-disciplinary platform for the analysis of innate immune cell function and fungal pathogenesis. These studies have revealed novel aspects of phagocytosis that could only be observed using systematic temporal analysis of the molecular and cellular interactions between human phagocytes and fungal pathogens and infectious microorganisms more generally. For example, we have begun to define the following: (a) the components of the cell surface required for each stage of the process of recognition, engulfment and killing of fungal cells1, 6, 7, 8; (b) how surface geometry influences the efficiency of macrophage uptake and killing of yeast and hyphal cells7; and (c) how engulfment leads to alteration of the cell cycle and behavior of macrophages 9, 10.In contrast to single time point snapshots, live-cell video microscopy enables a wide variety of host cells and pathogens to be studied as continuous sequences over lengthy time periods, providing spatial and temporal information on a broad range of dynamic processes, including cell migration, replication and vesicular trafficking. Here we describe in detail how to prepare host and fungal cells, and to conduct the video microscopy experiments. These methods can provide a user-guide for future studies with other phagocytes and microorganisms. 相似文献
995.
Anne Fiebig Silke Pradella J?rn Petersen Victoria Michael Orsola P?uker Manfred Rohde Markus G?ker Hans-Peter Klenk Irene Wagner-D?bler 《Standards in genomic sciences》2013,7(3):440-448
Hoeflea phototrophica Biebl et al. 2006 is a member of the family Phyllobacteriaceae in the order Rhizobiales, which is thus far only partially characterized at the genome level. This marine bacterium contains the photosynthesis reaction-center genes pufL and pufM and is of interest because it lives in close association with toxic dinoflagellates such as Prorocentrum lima. The 4,467,792 bp genome (permanent draft sequence) with its 4,296 protein-coding and 69 RNA genes is a part of the Marine Microbial Initiative. 相似文献
996.
Anne Fiebig Silke Pradella J?rn Petersen Orsola P?uker Victoria Michael Heinrich Lünsdorf Markus G?ker Hans-Peter Klenk Irene Wagner-D?bler 《Standards in genomic sciences》2013,7(3):413-426
Labrenzia alexandrii Biebl et al. 2007 is a marine member of the family Rhodobacteraceae in the order Rhodobacterales, which has thus far only partially been characterized at the genome level. The bacterium is of interest because it lives in close association with the toxic dinoflagellate Alexandrium lusitanicum. Ultrastructural analysis reveals R-bodies within the bacterial cells, which are primarily known from obligate endosymbionts that trigger “killing traits” in ciliates (Paramecium spp.). Genomic traits of L. alexandrii DFL-11T are in accordance with these findings, as they include the reb genes putatively involved in R-body synthesis. Analysis of the two extrachromosomal elements suggests a role in heavy-metal resistance and exopolysaccharide formation, respectively. The 5,461,856 bp long genome with its 5,071 protein-coding and 73 RNA genes consists of one chromosome and two plasmids, and has been sequenced in the context of the Marine Microbial Initiative. 相似文献
997.
Chao Yuan Hai-Ying Wang Chang-Sheng Wu Yang Jiao Ming Li Yan-Yan Wang Shu-Qi Wang Zun-Tian Zhao Hong-Xiang Lou 《Phytochemistry letters》2013,6(4):662-666
A new austdiol analog myxodiol A (1), three novel fulvic acid derivatives myxotrichin A–C (2–4), and a new citromycetin analog myxotrichin D (5), were isolated from an endolichenic fungus Myxotrichum sp. inhabiting the lichen Cetraria islandica (L.) Ach. The structures of these compounds were elucidated unequivocally on the basis of comprehensive analysis of MS and NMR data. Compounds 2 and 5 displayed very weak cytotoxicity against human leukemia cell line K562, and compounds 1 showed very weak antifungal activity against Candida albicans (sc5314). 相似文献
998.
Two new cadinane-type sesquiterpenes, hypocreaterpenes A (1) and B (2), along with five known compounds (3–7) were isolated from a marine-derived fungus Hypocreales sp. strain HLS-104 isolated from a sponge Gelliodes carnosa. Their structures were determined by a combination of spectroscopic methods. All compounds were tested for the inhibitory effects on the nitric oxide (NO) production in lipopolysaccharide (LPS)-treated RAW264.7 cells. Among them, compounds 3 and 6 showed moderate anti-inflammatory activity with average maximum inhibition (Emax) values of 10.22% and 26.46% at 1 μM, respectively. 相似文献
999.