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211.
A phylogenetic analysis of selected oestroid taxa based on 66 morphological traits and sequences from three nuclear protein‐coding genes (CAD, MAC, MCS) resolved the composition and phylogenetic position of the former subfamily Polleniinae of the Calliphoridae – here resurrected at family rank as Polleniidae Brauer & Bergenstamm, 1889 stat. rev. Six species are transferred from the family Rhinophoridae to the Polleniidae: the Palaearctic genus Alvamaja Rognes, along with its single species Alvamaja chlorometallica Rognes, and five Afrotropical species comprising the carinata‐group formerly in the genus Phyto Robineau‐Desvoidy but here assigned to genus Morinia Robineau‐Desvoidy, i.e. M. carinata (Pape, 1987) comb.n. , M. lactineala (Pape, 1997) comb.n. , M. longirostris (Crosskey, 1977) comb.n. , M. royi (Pape, 1997) comb.n. and M. stuckenbergi (Crosskey, 1977) comb.n. The Polleniidae are monophyletic and, in agreement with most recent phylogenetic reconstructions, sister to the Tachinidae. The female of A. chlorometallica and a new species of Morinia of the carinata‐group (Morinia tsitsikamma sp.n. from South Africa) are described. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:25B0C220‐DEE4‐4B0C‐88EA‐35FDE298EBC5 .  相似文献   
212.
Hydrolytic enzymatic activity in deep-sea sediments   总被引:5,自引:0,他引:5  
Abstract Hydrolytic activities of five enzymes were measured in deep-sea sediment cores at three stations under in situ temperature and pressure in the NE-Atlantic in March/April and July/August 1992. Generally, activity profiles declined vertically in the upper 10 cm of the cores. Experiments under in situ pressure were not significantly different from measurements under surface conditions. The ranking of potential activity rates in the top sediment horizon was: aminopeptidase > esterase > chitobiase > β-glucosidase > α-glucosidase with ratios of 687/174/11/3/1. This is similar to ratios obtained in marine aggregates from the upper mixed layer, thus supporting the idea of pelagic-benthic coupling in the open ocean. The vertical activity profiles show that the biochemical composition, and thereby the nutritive quality of the degradable material, changed with depth in the sediment cores. About 518 mg carbon was potentially mobilized in the 0–1 cm sediment horizon per square meter per day. This contrasts with the input of particulate organic carbon to the sea floor in this area of only 2.74 mg C m2 d−1, determined by sediment traps, which indicates that the deep-sea benthic community can rapidly utilize sedimenting particulate organic material and highlights the importance of extracellular enzyme activity in the sediment biogeochemical loop.  相似文献   
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The fundamental differences between monogastric animals and ruminants as regards the handling of dietary carbohydrates and as regards the relative importance of gluconeogenesis, rise interesting questions as to the factors regulating the secretion of growth hormone and insulin in poly gastric animals.  相似文献   
215.
Sundt  Håkon  Alfredsen  Knut  Museth  Jon  Forseth  Torbjørn 《Hydrobiologia》2022,849(2):509-525
Hydrobiologia - While many studies provide microscale relationships between fish and habitat characteristics, studies covering longer river reaches are scarce. Modern remote sensing...  相似文献   
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MOTIVATION: Experimental techniques in proteomics have seen rapid development over the last few years. Volume and complexity of the data have both been growing at a similar rate. Accordingly, data management and analysis are one of the major challenges in proteomics. Flexible algorithms are required to handle changing experimental setups and to assist in developing and validating new methods. In order to facilitate these studies, it would be desirable to have a flexible 'toolbox' of versatile and user-friendly applications allowing for rapid construction of computational workflows in proteomics. RESULTS: We describe a set of tools for proteomics data analysis-TOPP, The OpenMS Proteomics Pipeline. TOPP provides a set of computational tools which can be easily combined into analysis pipelines even by non-experts and can be used in proteomics workflows. These applications range from useful utilities (file format conversion, peak picking) over wrapper applications for known applications (e.g. Mascot) to completely new algorithmic techniques for data reduction and data analysis. We anticipate that TOPP will greatly facilitate rapid prototyping of proteomics data evaluation pipelines. As such, we describe the basic concepts and the current abilities of TOPP and illustrate these concepts in the context of two example applications: the identification of peptides from a raw dataset through database search and the complex analysis of a standard addition experiment for the absolute quantitation of biomarkers. The latter example demonstrates TOPP's ability to construct flexible analysis pipelines in support of complex experimental setups. AVAILABILITY: The TOPP components are available as open-source software under the lesser GNU public license (LGPL). Source code is available from the project website at www.OpenMS.de  相似文献   
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All Staphylococcus aureus genomes contain a genomic island, which is termed νSaα and characterized by two clusters of tandem repeat sequences, i.e. the exotoxin (set) and ''lipoprotein-like'' genes (lpl). Based on their structural similarities the νSaα islands have been classified as type I to IV. The genomes of highly pathogenic and particularly epidemic S. aureus strains (USA300, N315, Mu50, NCTC8325, Newman, COL, JH1 or JH9) belonging to the clonal complexes CC5 and CC8 bear a type I νSaα island. Since the contribution of the lpl gene cluster encoded in the νSaα island to virulence is unclear to date, we deleted the entire lpl gene cluster in S. aureus USA300. The results showed that the mutant was deficient in the stimulation of pro-inflammatory cytokines in human monocytes, macrophages and keratinocytes. Purified lipoprotein Lpl1 was further shown to elicit a TLR2-dependent response. Furthermore, heterologous expression of the USA300 lpl cluster in other S. aureus strains enhanced their immune stimulatory activity. Most importantly, the lpl cluster contributed to invasion of S. aureus into human keratinocytes and mouse skin and the non-invasive S. carnosus expressing the lpl gene cluster became invasive. Additionally, in a murine kidney abscess model the bacterial burden in the kidneys was higher in wild type than in mutant mice. In this infection model the lpl cluster, thus, contributes to virulence. The present report is one of the first studies addressing the role of the νSaα encoded lpl gene cluster in staphylococcal virulence. The finding that the lpl gene cluster contributes to internalization into non-professional antigen presenting cells such as keratinocytes highlights the lpl as a new cell surface component that triggers host cell invasion by S. aureus. Increased invasion in murine skin and an increased bacterial burden in a murine kidney abscess model suggest that the lpl gene cluster serves as an important virulence factor.  相似文献   
220.
Autophagy is a lysosome-dependent degradation system conserved among eukaryotes. The mammalian Atg1 homologues, Unc-51 like kinase (ULK) 1 and 2, are multifunctional proteins with roles in autophagy, neurite outgrowth, and vesicle transport. The mammalian ULK complex involved in autophagy consists of ULK1, ULK2, ATG13, FIP200, and ATG101. We have used pulldown and peptide array overlay assays to study interactions between the ULK complex and six different ATG8 family proteins. Strikingly, in addition to ULK1 and ULK2, ATG13 and FIP200 interacted with human ATG8 proteins, all with strong preference for the GABARAP subfamily. Similarly, yeast and Drosophila Atg1 interacted with their respective Atg8 proteins, demonstrating the evolutionary conservation of the interaction. Use of peptide arrays allowed precise mapping of the functional LIR motifs, and two-dimensional scans of the ULK1 and ATG13 LIR motifs revealed which substitutions that were tolerated. This information, combined with an analysis of known LIR motifs, provides us with a clearer picture of sequence requirements for LIR motifs. In addition to the known requirements of the aromatic and hydrophobic residues of the core motif, we found the interactions to depend strongly on acidic residues surrounding the central core LIR motifs. A preference for either a hydrophobic residue or an acidic residue following the aromatic residue in the LIR motif is also evident. Importantly, the LIR motif is required for starvation-induced association of ULK1 with autophagosomes. Our data suggest that ATG8 proteins act as scaffolds for assembly of the ULK complex at the phagophore.  相似文献   
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